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1.
Perfusion ; 37(3): 249-256, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33626985

RESUMO

OBJECTIVES: Out-of-hospital cardiac arrest (OHCA) is associated with excessively high mortality rates. Recent studies suggest benefits from extracorporeal cardiopulmonary resuscitation (ECPR) performed in selected patients. We sought to present the first results from our interdisciplinary ECPR program with a particular focus on early outcomes and potential risk factors associated with in-hospital mortality. METHODS: Between January 2016 and December 2019, 44 patients who underwent ECPR selected according to our institutional ECPR protocol were retrospectively analyzed regarding pre-hospital, in-hospital, and early outcome parameters. Patients were divided into survivors (S) and non-survivors (NS). Statistical analysis of risk factors regarding in-hospital mortality of the patient cohort analyzed was performed. RESULTS: The mean age of the population was 53 ± 12 years, with most patients being male (n = 40). The leading cause of cardiac arrest (CA) was myocardial infarction (n = 24, 55%). The median hospital stay was 1 (1;13) day. Twenty-three percent of patients (n = 10) were discharged from hospital including eight patients (18%) with CPC 1-2. Survivors showed a trend toward shorter pre-hospital CPR duration (60 (59;60) min (S) vs 60 (55;90) min (NS), p = 0.07). CONCLUSION: Establishing ECPR programs in large population areas offers the option to improve survival rates for OHCA patients. Stringent compliance of institutional criteria (mainly age, witnessed arrest, and time of pre-hospital resuscitation) and providing ECPR to strictly selected patients seems to be a vital factor for such programs' success. Pre-clinical settings and therapeutic measures must be adjusted in this regard to improve outcomes for this highly demanding patient cohort.


Assuntos
Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca Extra-Hospitalar , Adulto , Idoso , Reanimação Cardiopulmonar/métodos , Oxigenação por Membrana Extracorpórea/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos , Resultado do Tratamento
2.
Acta Biochim Biophys Sin (Shanghai) ; 51(3): 323-330, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30721967

RESUMO

Protein phosphatase 1 isoforms α, ß, and γ (PP1α, PP1ß, and PP1γ) are highly homologous in the catalytic domains but have distinct subcellular localizations. In this study, we utilized both primary cell culture and knockout mice to investigate the isoform-specific roles of PP1s in the heart. In both neonatal and adult cardiac myocytes, PP1ß was mainly localized in the nucleus, compared to the predominant presence of PP1α and PP1γ in the cytoplasm. Adenovirus-mediated overexpression of PP1α led to decreased phosphorylation of phospholamban, which was not influenced by overexpression of either PP1ß or PP1γ. Interestingly, only cardiac-specific knockout of PP1ß resulted in increased HDAC7 phosphorylation, consistent with the predominant nuclear localization of PP1ß. Functionally, deletion of either PP1 isoform resulted in reduced fractional shortening in aging mice, however only PP1ß deletion resulted in interstitial fibrosis in mice as early as 3 weeks of age. Deletion of neither PP1 isoform had any effect on pathological cardiac hypertrophy induced by 2 weeks of pressure overload stimulation. Together, our data suggest that PP1 isoforms have differential localizations to regulate the phosphorylation of their specific substrates for the physiological function in the heart.


Assuntos
Miócitos Cardíacos/enzimologia , Proteína Fosfatase 1/fisiologia , Animais , Células Cultivadas , Feminino , Coração/fisiologia , Isoenzimas/fisiologia , Masculino , Camundongos , Fosforilação , Proteína Fosfatase 1/análise
3.
Bioorg Med Chem Lett ; 27(4): 1050-1054, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28110869

RESUMO

The pore-forming protein perforin is a key component of mammalian cell-mediated immunity and essential to the pathway that allows elimination of virus-infected and transformed cells. Perforin activity has also been implicated in certain auto-immune conditions and therapy-induced conditions such as allograft rejection and graft versus host disease. An inhibitor of perforin activity could be used as a highly specific immunosuppressive treatment for these conditions, with reduced side-effects compared to currently accepted therapies. Previously identified first-in-class inhibitors based on a 2-thioxoimidazolidin-4-one core show suboptimal physicochemical properties and toxicity toward the natural killer (NK) cells that secrete perforin in vivo. The current benzenesulphonamide-based series delivers a non-toxic bioisosteric replacement possessing improved solubility.


Assuntos
Imunossupressores/farmacologia , Perforina/antagonistas & inibidores , Sulfonamidas/farmacologia , Linhagem Celular Tumoral , Humanos , Imunossupressores/química , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Solubilidade , Relação Estrutura-Atividade , Sulfonamidas/química , Benzenossulfonamidas
4.
Bioorg Med Chem Lett ; 26(2): 355-360, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26711151

RESUMO

Evolution from a furan-containing high-throughput screen (HTS) hit (1) resulted in isobenzofuran-1(3H)-one (2) as a potent inhibitor of the function of both isolated perforin protein and perforin delivered in situ by intact KHYG-1 NK cells. In the current study, structure-activity relationship (SAR) development towards a novel series of diarylthiophene analogues has continued through the use of substituted-benzene and -pyridyl moieties as bioisosteres for 2-thioxoimidazolidin-4-one (A) on a thiophene (B) -isobenzofuranone (C) scaffold. The resulting compounds were tested for their ability to inhibit perforin lytic activity in vitro. Carboxamide (23) shows a 4-fold increase over (2) in lytic activity against isolated perforin and provides good rationale for continued development within this class.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , Perforina/antagonistas & inibidores , Tiofenos/química , Tiofenos/farmacologia , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Perforina/metabolismo , Relação Estrutura-Atividade
5.
Bioorg Med Chem ; 24(22): 6075-6081, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27745990

RESUMO

A Pd-catalysed amination method is used to convert seco-CBI, a synthetic analogue of the alkylating subunit of the duocarmycin natural products, from the phenol to amino form. This allows efficient enantioselective access to the more potent S enantiomer of aminoCBI and its incorporation into analogues of DNA minor groove cross-linking agents. Evaluation in a panel of nine human tumour cell lines shows that the bifunctional agents containing aminoCBI are generally less cytotoxic than their phenolCBI analogues and more susceptible to P-glycoprotein-mediated resistance. However, all bifunctional agents are potent cytotoxins, some in the sub-pM IC50 range, with in vitro properties that compare favourably with established microtubule-targeted ADC payloads.


Assuntos
Anticorpos/farmacologia , Antineoplásicos/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , Indóis/farmacologia , Anticorpos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Reagentes de Ligações Cruzadas/síntese química , Reagentes de Ligações Cruzadas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Duocarmicinas , Humanos , Indóis/química , Estrutura Molecular , Pirrolidinonas/química , Pirrolidinonas/farmacologia , Relação Estrutura-Atividade
6.
PLoS One ; 19(5): e0304326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38809919

RESUMO

In the complex work environments of firefighting teams, it is often human error or difficulties in teamwork that lead to dangerous situations. To prevent these, it is essential to know the teamwork-related stressors and resources in firefighting operations. A measurement tool is needed to evaluate these stressors and resources. A successive instrument development process was conducted to identify the relevant teamwork-related stressors and resources in firefighting operations. First, interviews with experienced firefighters, and second, a document analysis were conducted and evaluated to provide an overview of the teamwork-related stressors and resources. Thereupon, a questionnaire, the REST-Q Fire, was developed asking about the experienced frequency and intensity of the identified teamwork-related stressors and resources in firefighting operations. Afterwards, an online study with firefighters was conducted (N = 491). CFAs confirmed the assumed structure of the REST-Q Fire and a positive correlation of the intensity of stressors with stress was shown (r = .19 - .27). Further, the resources were overall more frequently and intensively perceived than the stressors. The most important stressors were 'behavior of leaders' (M (SD)frequency = 2.80 (0.83), M (SD)intensity = 3.59 (1.12)), and 'behavior of team members' (M (SD)frequency = 2.77 (0.75), M (SD)intensity = 3.59 (1.05)). The most important resources, on the other hand, were 'knowledge about skills and behavior of team members' (M (SD)frequency = 3.96 (0.63), M (SD)intensity = 4.24 (0.78)), 'watch out for/ check on each other' (M (SD)frequency = 3.96 (0.70), M (SD)intensity = 4.20 (0.80)), and 'reliability of team members' (M (SD)frequency = 3.96 (0.51), M (SD)intensity = 4.16 (0.73)). As a result, training needs for trainees in the fire service and experienced firefighters were derived.


Assuntos
Bombeiros , Humanos , Bombeiros/psicologia , Inquéritos e Questionários , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Estresse Psicológico
7.
PCN Rep ; 3(3): e223, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38962000

RESUMO

The aim of this scoping review was to synthesize published studies and ongoing clinical trials of psychological interventions for mental health problems associated with COVID-19 infection. The study protocol was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews. We conducted systematic searches for studies published or registered between January 2020 and October 2022 using eight scientific databases and clinical trial registries, which identified 40 complete published studies and 53 ongoing clinical trials. We found that most studies were randomized controlled trials (74%) while the remaining used study designs of lower methodological quality. Most studies investigated interventions for acute COVID-19 patients (74%) and others explored post-COVID conditions (PCC) or recovered patients. Cognitive and behavioral therapies were the main intervention approaches (31%), followed by multidisciplinary programs (21%) and mindfulness (17%). The most frequently evaluated outcomes were anxiety (33%), depression (26%), quality of life (13%), and insomnia (10%). No studies on youths, older people, or marginalized communities were found. These findings summarize the burgeoning research on a range of psychological interventions for individuals infected with COVID-19. However, the field is in its infancy and further research to develop an evidence base for targeted care is necessary. The gaps identified in the current study also highlight the need for more research on youths, older people, and members of marginalized communities, and PCC patients. It is important to ascertain interventions and delivery strategies that are not only effective and affordable but also allow high scalability and accessibility.

8.
J Biol Chem ; 287(53): 44017-26, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23135281

RESUMO

The multiprotein complex Mediator is a coactivator of RNA polymerase (Pol) II transcription that is required for the regulated expression of protein-coding genes. Mediator serves as an end point of signaling pathways and regulates Pol II transcription, but the mechanisms it uses are not well understood. Here, we used mass spectrometry and dynamic transcriptome analysis to investigate a functional role of Mediator phosphorylation in gene expression. Affinity purification and mass spectrometry revealed that Mediator from the yeast Saccharomyces cerevisiae is phosphorylated at multiple sites of 17 of its 25 subunits. Mediator phosphorylation levels change upon an external stimulus set by exposure of cells to high salt concentrations. Phosphorylated sites in the Mediator tail subunit Med15 are required for suppression of stress-induced changes in gene expression under non-stress conditions. Thus dynamic and differential Mediator phosphorylation contributes to gene regulation in eukaryotic cells.


Assuntos
Regulação Fúngica da Expressão Gênica , Complexo Mediador/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica , Motivos de Aminoácidos , Complexo Mediador/química , Complexo Mediador/genética , Fosforilação , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
9.
J Sports Sci ; 31(3): 256-63, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23062070

RESUMO

Few studies have focused on the effect of posture during sprint start. The aim of this study was to measure the effect of the modification of horizontal distance between the blocks during sprint start on three dimensional (3D) joint angular velocity. Nine trained sprinters started using three different starting positions (bunched, medium and elongated). They were equipped with 63 passive reflective markers, and an opto-electronic Motion Analysis system was used to collect the 3D marker trajectories. During the pushing phase on the blocks, norm of the joint angular velocity (NJAV), 3D Euler angular velocity (EAV) and pushing time on the blocks were calculated. The results demonstrated that the decrease of the block spacing induces an opposite effect on the angular velocity of joints of the lower and the upper limbs. The NJAV of the upper limbs is greater in the bunched start, whereas the NJAV of the lower limbs is smaller. The modifications of NJAV were due to a combination of the movement of the joints in the different degrees of freedom. The medium start seems to be the best compromise because it leads, in a short pushing time, to a combination of optimal joint velocities for upper and lower segments.


Assuntos
Articulações , Extremidade Inferior , Movimento , Postura , Corrida , Análise e Desempenho de Tarefas , Extremidade Superior , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Modelos Biológicos , Adulto Jovem
10.
BMJ Open ; 13(3): e069386, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36863745

RESUMO

INTRODUCTION: Mental health symptoms such as depression, anxiety and sleep problems are commonly observed in individuals suffering from acute COVID-19 infection to post-COVID-19 syndrome. Studies have provided preliminary evidence for the efficacies of cognitive behavioural therapy, mindfulness-based interventions, acceptance and commitment therapy, and many other treatments for this population. Although there have been attempts to synthesise the literature on these psychological interventions, previous reviews have been limited in terms of the sources, symptoms and interventions that they included. Furthermore, most studies reviewed were conducted in early 2020, when COVID-19 had only recently been classified as a global pandemic. Since then, substantial research has been conducted. As such, we sought to provide an updated synthesis of the available evidence of treatments for the range of mental health symptoms associated with COVID-19. METHODS AND ANALYSIS: This scoping review protocol was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. Systematic searches were carried out on scientific databases (PubMed, Web of Science, PsycINFO and Scopus) and clinical trial registries (ClinicalTrials.gov, WHO ICTRP, EU Clinical Trials Register and Cochrane Central Register of Controlled Trials) to identify studies that have or will assess the efficacy or any aspects of psychological treatment for acute to post-COVID-19 syndrome. The search was conducted on 14 October 2022 and identified 17 855 potentially eligible sources/studies published since 1 January 2020 (duplicates removed). Six investigators will independently carry out titles and abstract screening, full-text screening and data charting and the results will be summarised using descriptive statistics and narrative synthesis. ETHICS AND DISSEMINATION: Ethical approval is not required for this review. The results will be disseminated through a peer-reviewed journal, conference presentations and/or academic newspapers. This scoping review has been registered with Open Science Framework (https://osf.io/wvr5t).


Assuntos
Terapia de Aceitação e Compromisso , COVID-19 , Humanos , Saúde Mental , Síndrome de COVID-19 Pós-Aguda , COVID-19/terapia , Ansiedade/terapia , Revisões Sistemáticas como Assunto , Literatura de Revisão como Assunto
11.
Mol Syst Biol ; 7: 458, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21206491

RESUMO

To obtain rates of mRNA synthesis and decay in yeast, we established dynamic transcriptome analysis (DTA). DTA combines non-perturbing metabolic RNA labeling with dynamic kinetic modeling. DTA reveals that most mRNA synthesis rates are around several transcripts per cell and cell cycle, and most mRNA half-lives range around a median of 11 min. DTA can monitor the cellular response to osmotic stress with higher sensitivity and temporal resolution than standard transcriptomics. In contrast to monotonically increasing total mRNA levels, DTA reveals three phases of the stress response. During the initial shock phase, mRNA synthesis and decay rates decrease globally, resulting in mRNA storage. During the subsequent induction phase, both rates increase for a subset of genes, resulting in production and rapid removal of stress-responsive mRNAs. During the recovery phase, decay rates are largely restored, whereas synthesis rates remain altered, apparently enabling growth at high salt concentration. Stress-induced changes in mRNA synthesis rates are predicted from gene occupancy with RNA polymerase II. DTA-derived mRNA synthesis rates identified 16 stress-specific pairs/triples of cooperative transcription factors, of which seven were known. Thus, DTA realistically monitors the dynamics in mRNA metabolism that underlie gene regulatory systems.


Assuntos
Perfilação da Expressão Gênica/métodos , Estabilidade de RNA , RNA Mensageiro/biossíntese , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulação Fúngica da Expressão Gênica , Genoma Fúngico , Meia-Vida , Modelos Logísticos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Fúngico/biossíntese , RNA Fúngico/genética , RNA Mensageiro/genética , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Transcrição Gênica
12.
Bioorg Med Chem ; 20(3): 1319-36, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22244072

RESUMO

An aryl-substituted isobenzofuran-1(3H)-one lead compound was identified from a high throughput screen designed to find inhibitors of the lymphocyte pore-forming protein perforin. A series of analogs were then designed and prepared, exploring structure-activity relationships through variation of 2-thioxoimidazolidin-4-one and furan subunits on an isobenzofuranone core. The ability of the resulting compounds to inhibit the lytic activity of both isolated perforin protein and perforin delivered in situ by intact KHYG-1 natural killer effector cells was determined. Several compounds showed excellent activity at concentrations that were non-toxic to the killer cells. This series represents a significant improvement on previous classes of compounds, being substantially more potent and largely retaining activity in the presence of serum.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , Imunossupressores/química , Imunossupressores/farmacologia , Perforina/antagonistas & inibidores , Linhagem Celular , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Perforina/metabolismo
13.
Nat Hazards (Dordr) ; 112(2): 1273-1294, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35194318

RESUMO

Resilience has become important in disaster preparedness and response. Unfortunately, little is known about resilience at the household level. This study presents the results of a survey into individual and household level preparedness to disaster events in Yangon, Myanmar, which is prone to natural disasters such as tropical cyclones, flooding, and earthquakes. The study aimed to understand societal resilience and to provide information that could be used to develop a holistic framework. In four different Yangon townships, 440 households were interviewed. The results of the survey indicate how risk preparedness could be improved by specific measures related to the following five factors: (1) increasing the general public's knowledge of first aid and its role in preparedness; (2) improving mobile phone infrastructure and capacity building in its usage so that it can be used for communication during disasters, along with building up a redundant communication structure; (3) better use and organisation of volunteer potential; (4) more specific involvement of religious and public buildings for disaster response; and (5) developing specific measures for improving preparedness in urban areas, where the population often has reduced capacities for coping with food supply insufficiencies due to the high and immediate availability of food, shops and goods in regular times. The findings of this survey have led to specific recommendations for Yangon. The identified measures represent a first step in developing a more general framework. Future research could investigate the transferability of these measures to other areas and thus their suitability as a basis for a framework.

14.
ACS Pharmacol Transl Sci ; 5(6): 429-439, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35711815

RESUMO

Perforin is a key effector of lymphocyte-mediated cell death pathways and contributes to transplant rejection of immunologically mismatched grafts. We have developed a novel series of benzenesulfonamide (BZS) inhibitors of perforin that can mitigate graft rejection during allogeneic bone marrow/stem cell transplantation. Eight such perforin inhibitors were tested for their murine pharmacokinetics, plasma protein binding, and their ability to block perforin-mediated lysis in vitro and to block the rejection of major histocompatibility complex (MHC)-mismatched mouse bone marrow cells. All compounds showed >99% binding to plasma proteins and demonstrated perforin inhibitory activity in vitro and in vivo. A lead compound, compound 1, that showed significant increases in allogeneic bone marrow preservation was evaluated for its plasma pharmacokinetics and in vivo efficacy at multiple dosing regimens to establish a pharmacokinetic/pharmacodynamic (PK/PD) relationship. The strongest PK/PD correlation was observed between perforin inhibition in vivo and time that total plasma concentrations remained above 900 µM, which correlates to unbound concentrations similar to 3× the unbound in vitro IC90 of compound 1. This PK/PD relationship will inform future dosing strategies of BZS perforin inhibitors to maintain concentrations above 3× the unbound IC90 for as long as possible to maximize efficacy and enhance progression toward clinical evaluation.

15.
Animals (Basel) ; 11(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34944138

RESUMO

Older horses and those prone to obesity may be at a higher risk for inflammation than younger and leaner counterparts. Previous research indicated a postprandial elevation in plasma concentrations of interleukin-1ß (IL-1ß), a pro-inflammatory cytokine, after consuming 1.2 g of non-structural carbohydrates/kilogram of body weight. However, these studies utilized horses of mixed age and body condition. The current study evaluated post-prandial IL-1ß concentrations in horses specifically comparing lean to over-conditioned and middle aged to older. Our results suggest that at least two weeks of daily consumption of a high non-structural carbohydrate diet is required to induce a post-prandial increase in IL-1ß concentrations in younger and leaner horses. In opposition to this, older and over-conditioned horses experience plasma increased on the first day of feeding and thereafter. Feeding management practices of older and over-conditioned individuals should emphasize lower non-structural carbohydrate intakes and further research should elucidate mechanisms of IL-1ß activation.

16.
Bioelectromagnetics ; 31(5): 391-405, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20213671

RESUMO

To improve the assessment of magnetic field exposures for occupational health studies, the Multiwave System III (MW3) was developed to capture personal exposures to the three-dimensional magnetic field vector B(t) in the 0-3000 Hz band. To process hundreds of full-shift MW3 measurements from epidemiologic studies, new computer programs were developed to calculate the magnetic field's physical properties and its interaction with biological systems through various mechanisms (magnetic induction, radical pair interactions, ion resonance, etc.). For automated calculations in the frequency domain, the software uses new algorithms that remove artifacts in the magnetic field's Fourier transform due to electronic noise and the person's motion through perturbations in the geomagnetic field from steel objects. These algorithms correctly removed the Fourier transform artifacts in 92% of samples and have improved the accuracy of frequency-dependent metrics by as much as 3300%. The output of the MwBatch software is a matrix of 41 exposure metrics calculated for each 2/15 s sample combined with 8 summary metrics for the person's full-period exposure, giving 294 summary-exposure metrics for each person monitored. In addition, the MwVisualizer software graphically explores the magnetic field's vector trace, its component waveforms, and the metrics over time. The output was validated against spreadsheet calculations with pilot data. This software successfully analyzed full-shift MW3 monitoring with 507 electric utility workers, comprising over 1 million vector waveforms. The software's output can be used to test hypotheses about magnetic field biology and disease with biophysical models and also assess compliance with exposure limits.


Assuntos
Artefatos , Saúde , Magnetismo , Exposição Ocupacional/efeitos adversos , Humanos , Movimento , Reprodutibilidade dos Testes , Software
17.
Front Bioeng Biotechnol ; 8: 1021, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042959

RESUMO

Variant allele frequencies (VAF) are an important measure of genetic variation that can be estimated at single-nucleotide variant (SNV) sites. RNA and DNA VAFs are used as indicators of a wide-range of biological traits, including tumor purity and ploidy changes, allele-specific expression and gene-dosage transcriptional response. Here we present a novel methodology to assess gene and chromosomal allele asymmetries and to aid in identifying genomic alterations in RNA and DNA datasets. Our approach is based on analysis of the VAF distributions in chromosomal segments (continuous multi-SNV genomic regions). In each segment we estimate variant probability, a parameter of a random process that can generate synthetic VAF samples that closely resemble the observed data. We show that variant probability is a biologically interpretable quantitative descriptor of the VAF distribution in chromosomal segments which is consistent with other approaches. To this end, we apply the proposed methodology on data from 72 samples obtained from patients with breast invasive carcinoma (BRCA) from The Cancer Genome Atlas (TCGA). We compare DNA and RNA VAF distributions from matched RNA and whole exome sequencing (WES) datasets and find that both genomic signals give very similar segmentation and estimated variant probability profiles. We also find a correlation between variant probability with copy number alterations (CNA). Finally, to demonstrate a practical application of variant probabilities, we use them to estimate tumor purity. Tumor purity estimates based on variant probabilities demonstrate good concordance with other approaches (Pearson's correlation between 0.44 and 0.76). Our evaluation suggests that variant probabilities can serve as a dependable descriptor of VAF distribution, further enabling the statistical comparison of matched DNA and RNA datasets. Finally, they provide conceptual and mechanistic insights into relations between structure of VAF distributions and genetic events. The methodology is implemented in a Matlab toolbox that provides a suite of functions for analysis, statistical assessment and visualization of Genome and Transcriptome allele frequencies distributions. GeTallele is available at: https://github.com/SlowinskiPiotr/GeTallele.

18.
J Med Chem ; 63(5): 2229-2239, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-31525966

RESUMO

Perforin is a key effector protein in the vertebrate immune system and is secreted by cytotoxic T lymphocytes and natural killer cells to help eliminate virus-infected and transformed target cells. The ability to modulate perforin activity in vivo could be extremely useful, especially in the context of bone marrow stem cell transplantation where early rejection of immunologically mismatched grafts is driven by the recipient's natural killer cells, which overwhelmingly use perforin to kill their targets. Bone marrow stem cell transplantation is a potentially curative treatment for both malignant and nonmalignant disorders, but when the body recognizes the graft as foreign, it is rejected by this process, often with fatal consequences. Here we report optimization of a previously identified series of benzenesulfonamide-based perforin inhibitors for their physicochemical and pharmacokinetic properties, resulting in the identification of 16, the first reported small molecule able to prevent rejection of transplanted bone marrow stem cells in vivo by blocking perforin function.


Assuntos
Transplante de Medula Óssea , Rejeição de Enxerto/prevenção & controle , Perforina/antagonistas & inibidores , Transplante de Células-Tronco , Sulfonamidas/uso terapêutico , Animais , Linhagem Celular , Rejeição de Enxerto/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Perforina/imunologia , Sulfonamidas/química , Sulfonamidas/farmacocinética , Benzenossulfonamidas
19.
Int J Stem Cells ; 11(1): 48-60, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29699382

RESUMO

BACKGROUND AND OBJECTIVES: Bone marrow mesenchymal stem cells (BM-MSCs) are an attractive cell based therapy in the treatment of CNS demyelinating diseases such as multiple sclerosis (MS). Preclinical studies demonstrate that BM-MSCs can effectively reduce clinical burden and enhance recovery in experimental autoimmune encephalomyelitis (EAE), a commonly used animal model of MS. However, a number of recent clinical trials have not shown significant functional benefit following BM-MSC infusion into MS patients. One possibility for the discrepancy between animal and human studies is the source of the cells, as recent studies suggest BM-MSCs from MS patients or animals with EAE lack reparative efficacy compared to naïve cells. We sought to define important transcriptional and functional differences between diseased and naïve MSCs. METHODS AND RESULTS: We utilized RNA Sequencing (RNA-Seq) to assess changes in gene expression between BM-MSCs derived from EAE animals and those derived from healthy controls. We show that EAE alters the expression of a large number of genes in BM-MSCs and changes in gene expression are more pronounced in chronic versus acute disease. Bioinformatic analysis revealed extensive perturbations in BM-MSCs in pathways related to inflammation and the regulation of neural cell development. These changes suggest that signals from EAE derived BM-MSCs inhibit rather than enhance remyelination, and in-vitro studies showed that conditioned medium from EAE MSCs fails to support the development of mature oligodendrocytes, the myelinating cells of the CNS. CONCLUSIONS: These data provide insight into the failure of autologous BM-MSCs to promote recovery in MS and support the concept of utilizing non-autologous MSCs in future clinical trials.

20.
Sci Rep ; 7(1): 8287, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28811643

RESUMO

Asymmetric allele content in the transcriptome can be indicative of functional and selective features of the underlying genetic variants. Yet, imbalanced alleles, especially from diploid genome regions, are poorly explored in cancer. Here we systematically quantify and integrate the variant allele fraction from corresponding RNA and DNA sequence data from patients with breast cancer acquired through The Cancer Genome Atlas (TCGA). We test for correlation between allele prevalence and functionality in known cancer-implicated genes from the Cancer Gene Census (CGC). We document significant allele-preferential expression of functional variants in CGC genes and across the entire dataset. Notably, we find frequent allele-specific overexpression of variants in tumor-suppressor genes. We also report a list of over-expressed variants from non-CGC genes. Overall, our analysis presents an integrated set of features of somatic allele expression and points to the vast information content of the asymmetric alleles in the cancer transcriptome.


Assuntos
Alelos , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Elementos de Resposta , Feminino , Perfilação da Expressão Gênica , Variação Genética , Genótipo , Humanos , Mutação , Transcriptoma
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