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1.
FEBS Lett ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664232

RESUMEN

PC4 is a chromatin-associated protein and transcriptional coactivator whose role in gene regulation by wild-type p53 is now well known. Little is known about the roles of PC4 in tumor cells bearing mutant p53 genes. We show that PC4 associates with one of the tumor-associated gain-of-function p53 mutants, R273H. This association drives its recruitment to two promoters, UBE2C and MDR1, known to be responsible for imparting aggressive growth and resistance to many drugs. Here, we introduced a peptide that disrupts the PC4-R273Hp53 interaction to tumor cells bearing the R273HTP53 gene, which led to a lowering of MDR1 expression and abrogation of drug resistance in a mutant-specific manner. The results suggest that the PC4-R273Hp53 interaction may be a promising target for reducing proliferation and drug resistance in tumors.

2.
J Eval Clin Pract ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38567698

RESUMEN

BACKGROUND: Unsafe patient events not only entail a clinical impact but also lead to economic burden in terms of prolonged hospitalization or unintended harm and delay in care delivery. Monitoring and time-bound investigation of patient safety events (PSEs) is of paramount importance in a healthcare set-up. OBJECTIVES: To explore the safety incident reporting behaviour and the barriers in a hospital set-up. METHODS: The study had two sections: (a) Retrospective assessment of all safety incidents in the past 1 year, and (b) Understanding the barriers of safety reporting by interviewing the major stakeholders in patient safety reporting framework. Further root cause analysis and failure mode effect analysis were performed for the situation observed. Results were statistically analyzed. RESULTS: Of the total of 106 PSEs reported voluntarily to the system, the highest reporting functional group was that of nurses (40.57%), followed by physicians (18.87%) and pharmacists (17.92%). Among the various factors identified as barriers in safety incident reporting, fear of litigation was the most observed component. The most commonly observed event was those pertaining to medication management, followed by diagnostic delay. Glitches in healthcare delivery accounted for 8.73% of the total reported PSEs, followed by 5.72% of events occurring due to inter-stakeholder communication errors. 4.22% of the PSEs were attributed to organizational managerial dysfunctionalities. Majority of medication-related PSE has moderate risk prioritization gradation. CONCLUSION: Effective training and sensitization regarding the need to report the patient unsafe incidents or near misses to the healthcare system can help avert many untoward experiences. The notion of 'No Blame No Shame' should be well inculcated within the minds of each hospital unit such that even if an error occurs, its prompt reporting does not get harmed.

3.
Cancer Metastasis Rev ; 43(1): 175-195, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38233727

RESUMEN

T cells, a key component of cancer immunotherapy, undergo a variety of histone modifications and DNA methylation changes since their bone marrow progenitor stages before developing into CD8+ and CD4+ T cells. These T cell types can be categorized into distinct subtypes based on their functionality and properties, such as cytotoxic T cells (Tc), helper T cells (Th), and regulatory T cells (Treg) as subtypes for CD8+ and CD4+ T cells. Among these, the CD4+ CD25+ Tregs potentially contribute to cancer development and progression by lowering T effector (Teff) cell activity under the influence of the tumor microenvironment (TME). This contributes to the development of therapeutic resistance in patients with cancer. Subsequently, these individuals become resistant to monoclonal antibody therapy as well as clinically established immunotherapies. In this review, we delineate the different epigenetic mechanisms in cancer immune response and its involvement in therapeutic resistance. Furthermore, the possibility of epi-immunotherapeutic methods based on histone deacetylase inhibitors and histone methyltransferase inhibitors are under investigation. In this review we highlight EZH2 as the principal driver of cancer cell immunoediting and an immune escape regulator. We have addressed in detail how understanding T cell epigenetic regulation might bring unique inventive strategies to overcome drug resistance and increase the efficacy of cancer immunotherapy.


Asunto(s)
Epigénesis Genética , Neoplasias , Humanos , Inmunoterapia , Neoplasias/genética , Neoplasias/terapia , Linfocitos T Reguladores , Metilación de ADN , Microambiente Tumoral/genética
4.
ACS Omega ; 8(34): 31480-31492, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37663486

RESUMEN

Geological sequestration of CO2 in a coal seam is considered an attractive option to reduce the carbon footprint. It has an additional advantage of enhancing the recovery of coalbed methane, which has less sorption affinity toward coal in comparison to CO2. Desorption of gases from coal is controlled by various parameters, including reservoir depth and coal rank. A representative factor for desorption and diffusion in coal is the sorption time. It is an indicator which helps in estimation and evaluation of gas movement in the coal seam. Coals exhibiting high sorption time allow greater quantities of CO2 injection and hold potential for CO2 sequestration. Therefore, reliable and cost-effective estimation of sorption time is very important prior to investment in projects related to CO2 sequestration. Generally, proximate and gas content analyses are part of the preliminary analysis of coal for the assessment of its potential as a coal-bed methane reservoir. In this study, data generated using these analyses were found very useful for estimating the sorption time and CO2 sequestration potential of coal. The coal samples were collected from different depths of the Mand Raigarh coalfield for testing, and an empirical equation and artificial neural network (ANN)-based model have been developed to predict the sorption time of coal. The developed empirical equation predicts the sorption time with a coefficient of determination value of 0.88 and a root mean squared error value of ±1.07 days. Furthermore, the developed ANN model has been found to be very efficient in prediction with a correlation coefficient value of 0.97.

6.
Sci Rep ; 13(1): 5701, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-37029143

RESUMEN

There is increased concern about perverse incentives, quantitative performance metrics, and hyper-competition for funding and faculty positions in US academia. Recipients of the prestigious National Science Foundation Graduate Research Fellowships (n = 244) from Civil and Environmental Engineering (45.5%) and Computer Science and Engineering (54.5%) were anonymously surveyed to create a baseline snapshot of their perceptions, behaviors and experiences. NSF Fellows ranked scientific advancement as the top metric for evaluating academics followed by publishing in high-impact journals, social impact of research, and publication/citation counts. The self-reported rate of academic cheating was 16.7% and of research misconduct was 3.7%. Thirty-one percent of fellows reported direct knowledge of graduate peers cheating, and 11.9% had knowledge of research misconduct by colleagues. Only 30.7% said they would report suspected misconduct. A majority of fellows (55.3%) felt that mandatory ethics trainings left them unprepared for dealing with ethical issues. Fellows stated academic freedom, flexible schedules and opportunity to mentor students were the most positive aspects of academia, whereas pressures for funding, publication, and tenure were cited as the most negative aspects. These data may be useful in considering how to better prepare STEM graduate trainees for academic careers.


Asunto(s)
Mala Conducta Científica , Humanos , Motivación , Docentes , Ocupaciones , Estudiantes
7.
Chem Biol Drug Des ; 102(1): 126-136, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37105726

RESUMEN

HDM2, an E3 ubiquitin ligase, is a crucial regulator of many proliferation-related pathways. It is also one of the primary regulators of p53. USP7, a deubiquitinase, also plays a key role in the regulation of both p53 and HDM2, thus forming a small regulatory network with them. This network has emerged as an important drug target. Development of a synergistic combination targeting both proteins is desirable and important for regulating this module. We have developed a small helically constrained peptide that potently inhibited p53-HDM2 interaction and exerted anti-proliferative effects on p53+/+ cells. A combination of this peptide-when attached to cell entry and nuclear localization tags-and a USP7 inhibitor showed synergistic anti-proliferative effects against cells harboring wild-type alleles of p53. Synergistic inhibition of two important drug targets may lead to novel therapeutic strategies.


Asunto(s)
Proteínas Proto-Oncogénicas c-mdm2 , Proteína p53 Supresora de Tumor , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Peptidasa Específica de Ubiquitina 7/metabolismo , Péptidos/farmacología , Péptidos/metabolismo
8.
Clin Psychol Eur ; 5(1): e9577, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37065004

RESUMEN

Background: Exposure to waterborne lead during the Flint Water Crisis during April 2014-October 2015 is believed to have caused increased special education enrollment in Flint children. Method: This retrospective population-based cohort study utilized de-identified data for children under six years of age who had their blood lead tested during 2011 to 2019, and special education outcomes data for children enrolled in public schools for corresponding academic years (2011-12 to 2019-20) in Flint, Detroit (control city) and the State of Michigan. Trends in the following crisis-related covariates were also evaluated: waterborne contaminants, poverty, nutrition, city governance, school district policies, negative community expectations, media coverage and social media interactions. Results: Between 2011 and 2019, including the 2014-15 crisis period, the incidence of elevated blood lead in Flint children (≥ 5µg/dL) was always at least 47% lower than in the control city of Detroit (p < .0001) and was also never significantly higher than that for all children tested in Michigan (p = 0.33). Nonetheless, special education enrollment in Flint spiked relative to Detroit and Michigan (p < .0001). There is actually an inverse relationship between childhood blood lead and special education enrollment in Flint. Conclusion: This study failed to confirm any positive association between actual childhood blood lead levels and special education enrollment in Flint. Negative psychological effects associated with media predictions of brain damage could have created a self-fulfilling prophecy via a nocebo effect. The findings demonstrate a need for improved media coverage of complex events like the Flint Water Crisis.

9.
Cancer Epidemiol Biomarkers Prev ; 32(6): 768-775, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36958853

RESUMEN

BACKGROUND: Prostate cancer affects African American men disproportionately compared with men of other racial/ethnic groups. To identify biological bases for this health disparity, we sought to create a state-wide biobank of African American prostate cancer survivors in Florida. METHODS: African American men diagnosed with prostate cancer between 2013 and 2017 and living in Florida at diagnosis were identified through the State of Florida's cancer registry. Individuals were approached via mail and telephone, assessed for eligibility, and asked for informed consent. χ2 and t tests were conducted to identify differences between eligible and reachable individuals (i.e., had valid contact information) versus consented participants. RESULTS: Of the 5,960 eligible and reachable individuals, 3,904 were eligible and contacted at least once, and 578 consented [overall consent rate = 10% (578/5,960); adjusted consent rate = 15% (578/3,904)]. Statistically significant (Ps < 0.05) but small differences in demographic and clinical variables were observed. Consented participants were less likely to be older than 64 (35% vs. 41%) and less likely to have received radiotherapy (36% vs. 41%) and hormone therapy (16% vs. 21%), but more likely to have regional prostate cancer (13% vs. 11%) and have undergone surgery (44% vs. 39%). Consented participants did not differ from reachable individuals on other demographic and clinical factors (Ps > 0.05). CONCLUSIONS: Recruiting African American prostate cancer survivors to biobanking research through a cancer registry is feasible. However, the consent rate was low, and existing challenges limit consent and participation. IMPACT: Strategies for overcoming barriers to informed consent and increasing participation in biospecimen research are needed to address cancer disparities.


Asunto(s)
Supervivientes de Cáncer , Neoplasias de la Próstata , Masculino , Humanos , Negro o Afroamericano , Próstata , Bancos de Muestras Biológicas , Neoplasias de la Próstata/diagnóstico
10.
Diabetes Spectr ; 36(1): 52-58, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36818411

RESUMEN

Nutrition is an integral part of diabetes management. Caregiver nutritional knowledge has been implicated in glycemic management of youth with type 1 diabetes. This study assessed the nutritional knowledge of parents/caregivers of children newly diagnosed with type 1 diabetes. Findings suggest there is a need for more targeted support and training during the initial diagnosis and a desire for more technology-related resources such as virtual nutritionist-guided grocery shopping visits. Integrating these interventions into routine care for children with type 1 diabetes will help address the current gaps in caregiver nutritional literacy and their ability to provide appropriate care.

11.
Cancer Res ; 83(5): 657-666, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36661847

RESUMEN

Therapy resistance is imposing a daunting challenge on effective clinical management of breast cancer. Although the development of resistance to drugs is multifaceted, reprogramming of energy metabolism pathways is emerging as a central but heterogenous regulator of this therapeutic challenge. Metabolic heterogeneity in cancer cells is intricately associated with alterations of different signaling networks and activation of DNA damage response pathways. Here we consider how the dynamic metabolic milieu of cancer cells regulates their DNA damage repair ability to ultimately contribute to development of therapy resistance. Diverse epigenetic regulators are crucial in remodeling the metabolic landscape of cancer. This epigenetic-metabolic interplay profoundly affects genomic stability of the cancer cells as well as their resistance to genotoxic therapies. These observations identify defining mechanisms of cancer epigenetics-metabolism-DNA repair axis that can be critical for devising novel, targeted therapeutic approaches that could sensitize cancer cells to conventional treatment strategies.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/genética , Resistencia a Antineoplásicos/genética , Reparación del ADN , Daño del ADN , Epigénesis Genética
12.
Subcell Biochem ; 100: 115-141, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36301493

RESUMEN

The accurate repair of genomic damage mediated by ionizing radiation (IR), chemo- or radiomimetic drugs, or other exogenous agents, is necessary for maintenance of genome integrity, preservation of cellular viability and prevention of oncogenic transformation. Eukaryotes have conserved mechanisms designed to perceive and repair the damaged DNA quite efficiently. Among the different types of DNA damage, double strand breaks (DSB) are the most detrimental. The cellular DNA DSB response is a hierarchical signaling network that integrates damage sensing and repair with chromatin structural changes that involve a range of pre-existing and induced covalent modifications. Recent studies have revealed that pre-existing histone modifications are important contributors within this signaling/repair network. This chapter discusses the role of a critical histone acetyl transferase (HAT) known as MOF (males absent on the first) and the histone deacetylases (HDACs) Sirtuins on histone H4K16 acetylation (H4K16ac) and DNA damage repair. We also discuss the role of this important histone modification in light of metabolic rewiring and its role in regulating human pathophysiologic states.


Asunto(s)
Envejecimiento , Histona Acetiltransferasas , Neoplasias , Sirtuinas , Humanos , Acetilación , Cromatina , ADN/metabolismo , Daño del ADN , Reparación del ADN , Histona Acetiltransferasas/genética , Histona Acetiltransferasas/metabolismo , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Histonas/metabolismo , Neoplasias/genética , Sirtuinas/genética , Sirtuinas/metabolismo
13.
Subcell Biochem ; 100: 269-336, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36301498

RESUMEN

Glucose metabolism plays a vital role in regulating cellular homeostasis as it acts as the central axis for energy metabolism, alteration in which may lead to serious consequences like metabolic disorders to life-threatening diseases like cancer. Malignant cells, on the other hand, help in tumor progression through abrupt cell proliferation by adapting to the changed metabolic milieu. Metabolic intermediates also vary from normal cells to cancerous ones to help the tumor manifestation. However, metabolic reprogramming is an important phenomenon of cells through which they try to maintain the balance between normal and carcinogenic outcomes. In this process, transcription factors and chromatin modifiers play an essential role to modify the chromatin landscape of important genes related directly or indirectly to metabolism. Our chapter surmises the importance of glucose metabolism and the role of metabolic intermediates in the cell. Also, we summarize the influence of histone effectors in reprogramming the cancer cell metabolism. An interesting aspect of this chapter includes the detailed methods to detect the aberrant metabolic flux, which can be instrumental for the therapeutic regimen of cancer.


Asunto(s)
Glucosa , Neoplasias , Humanos , Glucosa/metabolismo , Glucólisis/genética , Cromatina/genética , Neoplasias/metabolismo , Redes y Vías Metabólicas , Epigénesis Genética
14.
Cell Death Dis ; 13(9): 766, 2022 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-36064715

RESUMEN

Zinc Finger transcription factors are crucial in modulating various cellular processes, including differentiation. Chromatin reader Zinc Finger MYND (Myeloid, Nervy, and DEAF-1) type containing 8 (ZMYND8), an All-Trans Retinoic Acid (ATRA)-responsive gene, was previously shown to play a crucial role in promoting the expression of neuronal-lineage committed genes. Here, we report that ZMYND8 promotes neuronal differentiation by positively regulating canonical MAPT protein-coding gene isoform, a key player in the axonal development of neurons. Additionally, ZMYND8 modulates gene-isoform switching by epigenetically silencing key regulatory regions within the MAPT gene, thereby suppressing the expression of non-protein-coding isoforms such as MAPT213. Genetic deletion of ZMYND8 led to an increase in the MAPT213 that potentially suppressed the parental MAPT protein-coding transcript expression related to neuronal differentiation programs. In addition, ectopic expression of MAPT213 led to repression of MAPT protein-coding transcript. Similarly, ZMYND8-driven transcription regulation was also observed in other neuronal differentiation-promoting genes. Collectively our results elucidate a novel mechanism of ZMYND8-dependent transcription regulation of different neuronal lineage committing genes, including MAPT, to promote neural differentiation.


Asunto(s)
ARN Largo no Codificante , Diferenciación Celular/genética , Cromatina , Regulación de la Expresión Génica , ARN Largo no Codificante/genética , Tretinoina/farmacología , Proteínas Supresoras de Tumor/metabolismo
15.
Cancer Causes Control ; 33(8): 1095-1105, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35773504

RESUMEN

PURPOSE: Prior cancer research is limited by inconsistencies in defining rurality. The purpose of this study was to describe the prevalence of cancer risk factors and cancer screening behaviors across various county-based rural classification codes, including measures reflecting a continuum, to inform our understanding of cancer disparities according to the extent of rurality. METHODS: Using an ecological cross-sectional design, we examined differences in cancer risk factors and cancer screening behaviors from the Behavioral Risk Factor Surveillance System and National Health Interview Survey (2008-2013) across rural counties and between rural and urban counties using four rural-urban classification codes for counties and county-equivalents in 2013: U.S. Office of Management and Budget, National Center for Health Statistics, USDA Economic Research Service's rural-urban continuum codes, and Urban Influence Codes. RESULTS: Although a rural-to-urban gradient was not consistently evident across all classification codes, the prevalence of smoking, obesity, physical inactivity, and binge alcohol use increased (all ptrend < 0.03), while colorectal, cervical and breast cancer screening decreased (all ptrend < 0.001) with increasing rurality. Differences in the prevalence of risk factors and screening behaviors across rural areas were greater than differences between rural and urban counties for obesity (2.4% vs. 1.5%), physical activity (2.9% vs. 2.5%), binge alcohol use (3.4% vs. 0.4%), cervical cancer screening (6.8% vs. 4.0%), and colorectal cancer screening (4.4% vs. 3.8%). CONCLUSIONS: Rural cancer disparities persist across multiple rural-urban classification codes, with marked variation in cancer risk factors and screening evident within rural regions. Focusing only on a rural-urban dichotomy may not sufficiently capture subpopulations of rural residents at greater risk for cancer and cancer-related mortality.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias del Cuello Uterino , Estudios Transversales , Femenino , Humanos , Obesidad , Factores de Riesgo , Población Rural , Estados Unidos/epidemiología , Población Urbana
16.
J Biol Chem ; 298(8): 102200, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35772497

RESUMEN

DNA and core histones are hierarchically packaged into a complex organization called chromatin. The nucleosome assembly protein (NAP) family of histone chaperones is involved in the deposition of histone complexes H2A/H2B and H3/H4 onto DNA and prevents nonspecific aggregation of histones. Testis-specific Y-encoded protein (TSPY)-like protein 5 (TSPYL5) is a member of the TSPY-like protein family, which has been previously reported to interact with ubiquitin-specific protease USP7 and regulate cell proliferation and is thus implicated in various cancers, but its interaction with chromatin has not been investigated. In this study, we characterized the chromatin association of TSPYL5 and found that it preferentially binds histone H3/H4 via its C-terminal NAP-like domain both in vitro and ex vivo. We identified the critical residues involved in the TSPYL5-H3/H4 interaction and further quantified the binding affinity of TSPYL5 toward H3/H4 using biolayer interferometry. We then determined the binding stoichiometry of the TSPYL5-H3/H4 complex in vitro using a chemical cross-linking assay and size-exclusion chromatography coupled with multiangle laser light scattering. Our results indicate that a TSPYL5 dimer binds to either two histone H3/H4 dimers or a single tetramer. We further demonstrated that TSPYL5 has a specific affinity toward longer DNA fragments and that the same histone-binding residues are also critically involved in its DNA binding. Finally, employing histone deposition and supercoiling assays, we confirmed that TSPYL5 is a histone chaperone responsible for histone H3/H4 deposition and nucleosome assembly. We conclude that TSPYL5 is likely a new member of the NAP histone chaperone family.


Asunto(s)
Chaperonas de Histonas , Histonas , Proteínas Nucleares/metabolismo , ADN/metabolismo , Chaperonas de Histonas/genética , Histonas/metabolismo , Humanos , Masculino , Chaperonas Moleculares/metabolismo , Nucleosomas , Testículo/metabolismo , Peptidasa Específica de Ubiquitina 7/metabolismo
17.
FEBS J ; 289(21): 6694-6713, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35653238

RESUMEN

Hepatitis B virus (HBV) is the leading cause of liver disease ranging from acute and chronic hepatitis to liver cirrhosis and hepatocellular carcinoma (HCC). Studies have revealed that HBV infection broadly reprogrammes the host cellular metabolic processes for viral pathogenesis. Previous reports have shown that glycolysis and gluconeogenesis are among the most deregulated pathways during HBV infection. We noted that despite being one of the rate-limiting enzymes of gluconeogenesis, the role and regulation of Fructose-1,6-bisphosphatase 1 (FBP1) during HBV infection is not much explored. In this study, we report FBP1 upregulation upon HBV infection and unravel a novel mechanism of epigenetic reprogramming of FBP1 by HBV via utilizing host factor Speckled 110 kDa (Sp110). Here, we identified acetylated lysine 18 of histone H3 (H3K18Ac) as a selective interactor of Sp110 Bromodomain. Furthermore, we found that Sp110 gets recruited on H3K18Ac-enriched FBP1 promoter, and facilitates recruitment of deacetylase Sirtuin 2 (SIRT2) on that site in the presence of HBV. SIRT2 in turn brings its interactor and transcriptional activator Hepatocyte nuclear factor 4-alpha to the promoter, which ultimately leads to a loss of DNA methylation near the cognate site. Interestingly, this Sp110 driven FBP1 regulation during infection was found to promote viral-borne HCC progression. Moreover, Sp110 can be used as a prognostic marker for the hepatitis-mediated HCC patients, where high Sp110 expression significantly lowered their survival. Thus, the epigenetic reader protein Sp110 has potential to be a therapeutic target to challenge HBV-induced HCCs.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Epigénesis Genética , Fructosa , Fructosa-Bifosfatasa/genética , Fructosa-Bifosfatasa/metabolismo , Hepatitis B/complicaciones , Hepatitis B/genética , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/metabolismo , Factor Nuclear 4 del Hepatocito/genética , Neoplasias Hepáticas/patología , Sirtuina 2/metabolismo
18.
Biopolymers ; 113(7): e23492, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35615897

RESUMEN

Specific recognition of DNA base sequences by proteins is vital for life-cycles of all organisms. In a large number of crystal structures of protein-DNA complexes, DNA conformation significantly deviates from the canonical B-DNA structure. A key question is whether such alternate conformations exist prior to protein binding and one is selected for complexation or the structure observed is induced by protein binding. Non-canonical base pairs, such as Hoogsteen base pairs, are often observed in crystal structures of protein-DNA complexes. We decided to explore whether the occurrence of such non-canonical base pairs in protein-DNA complexes is induced by the protein or is selected from pre-existing conformations. Detailed quantum chemical calculations with dispersion-corrected density functional theory (DFT-D) indicated that most of the non-canonical base pairs with DNA bases are stable even in the absence of the interacting amino acids. However, the G:G Hoogsteen base pair, which also appears in the telomere structure, appears to be unstable in the absence of other stabilizing agents, such as positively charged amino acids. Thus, the stability of many of the non-canonical base pair containing duplexes may be close to the canonical B-DNA structure and hence energetically accessible in the ground state; suggesting that the selection from pre-existing conformations may be an important mechanism for observed non-canonical base pairs in protein-DNA complexes.


Asunto(s)
ADN Forma B , Aminoácidos , Emparejamiento Base , ADN/química , Enlace de Hidrógeno , Conformación de Ácido Nucleico
19.
J Integr Complement Med ; 28(6): 497-506, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35363576

RESUMEN

Objectives: To assess the feasibility, acceptability, and effects of Mindfulness Based Stress Reduction (MBSR) live online during the COVID-19 shutdown. Design: Mixed-methods study using a sequential explanatory design. Settings/location: Cohorts 1-4 took place in-person and Cohorts 5-6 took place over Zoom following the onset of the COVID-19 pandemic. Subjects: Participants were paying members of the general public enrolled in one of six live MBSR courses. Interventions: All MBSR courses followed the standard 8-week MBSR curriculum, led by experienced instructors. Outcome measures: Feasibility measured via class attendance, acceptability measured via the adapted Treatment Satisfaction Survey, and MBSR course effects measured by a focus group with Cohort 5, and the following assessments completed by all cohorts: Perceived Stress Scale-10, Generalized Anxiety Disorder-7, Patient Health Questionnaire-9 and the 36-item Short Form Survey. Results: 73 adults participated in six live MBSR courses (48 in the four in-person courses; 25 in the two online courses). Most of the participants identified as white, non-Hispanic, middle-aged females, with annual household income >$100,000. Course completion, defined as at least 6/8 classes attended, did not differ between in-person and online cohorts (84.1% versus 67.6%, respectively, p = 0.327). Participants in Cohort 5 who completed the course (n = 10) rated it as very important and useful for stress coping, and reported high likelihood of continuing their mindfulness practice (all ratings: between 8 and 10 on a 1-10 Likert scale), with open-ended responses corroborating their numerical ratings. Focus group (n = 6) responses indicated that online MBSR was positively received, reduced perceived loss of control, and improved quality of life and morale during the pandemic. Conclusions: Delivering MBSR live online can be feasible and acceptable for the general public, and is potentially beneficial, including during the social upheaval of the COVID-19 pandemic. Online delivery could help expand access to MBSR and address health inequities.


Asunto(s)
COVID-19 , Atención Plena , Adulto , COVID-19/epidemiología , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Atención Plena/métodos , Pandemias , Calidad de Vida , Estrés Psicológico/terapia
20.
Biosci Rep ; 42(4)2022 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-35438143

RESUMEN

Innate and acquired resistance towards the conventional therapeutic regimen imposes a significant challenge for the successful management of cancer for decades. In patients with advanced carcinomas, acquisition of drug resistance often leads to tumor recurrence and poor prognosis after the first therapeutic cycle. In this context, cancer stem cells (CSCs) are considered as the prime drivers of therapy resistance in cancer due to their 'non-targetable' nature. Drug resistance in cancer is immensely influenced by different properties of CSCs such as epithelial-to-mesenchymal transition (EMT), a profound expression of drug efflux pump genes, detoxification genes, quiescence, and evasion of apoptosis, has been highlighted in this review article. The crucial epigenetic alterations that are intricately associated with regulating different mechanisms of drug resistance, have been discussed thoroughly. Additionally, special attention is drawn towards the epigenetic mechanisms behind the interaction between the cancer cells and their microenvironment which assists in tumor progression and therapy resistance. Finally, we have provided a cumulative overview of the alternative treatment strategies and epigenome-modifying therapies that show the potential of sensitizing the resistant cells towards the conventional treatment strategies. Thus, this review summarizes the epigenetic and molecular background behind therapy resistance, the prime hindrance of present day anti-cancer therapies, and provides an account of the novel complementary epi-drug-based therapeutic strategies to combat drug resistance.


Asunto(s)
Resistencia a Antineoplásicos , Transducción de Señal , Resistencia a Antineoplásicos/genética , Epigénesis Genética/genética , Transición Epitelial-Mesenquimal/genética , Humanos , Recurrencia Local de Neoplasia/patología , Células Madre Neoplásicas/patología , Transducción de Señal/genética , Microambiente Tumoral/genética
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