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BACKGROUND: Depression and frailty are closely related, but the mechanisms by which depressed older adults are at an increased risk of becoming frail are still not well understood. AIM: To assess socioeconomic and depression-related risk factors for frailty in older adults with depression. METHODS: Observational and prospective cohort study, with 12-month follow-up, of nonfrail community-dwelling subjects aged ≥70 years old with depression. The main study factors were clinical characteristics of depression, including symptom severity (Hamilton Depression Rating Scale), accompanying anxiety and cognitive symptoms, pharmacological treatment, and social factors including educational level, income, housing conditions and living circumstances, and social network. Frailty status was established according to Fried criteria. RESULTS: We recruited and analysed 216 subjects (mean age 76.5 years; 74% women), 65 (30%) of whom were lost to follow-up. Annual incidence of frailty was 23.2 new cases/100 persons. Age, female gender, osteoarthritis, pain, number of medications, major depression, first-degree family history of depression, depressive symptom severity, low educational level, and low-income level were risk factors for frailty. The multivariate analysis showed that age (odds ratio [OR] = 1.16; 95% confidence interval [CI]: 1.04-1.29), visual analogue scale (VAS)-pain (OR = 1.25; 95% CI: 1.01-1.55), and severe or very severe depressive symptoms (OR = 37.36; 95% CI: 2.68-518.53) were significantly associated with incident frailty at 12 months of follow-up. CONCLUSIONS: Both clinical and social characteristics are risk factors for frailty, but severity of depressive symptoms had the highest independent effect on frailty in depressed aged subjects. Frailty requires a multidisciplinary approach that pays special attention to pain and depressed mood.
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Fragilidade , Idoso , Depressão/epidemiologia , Feminino , Idoso Fragilizado/psicologia , Fragilidade/epidemiologia , Avaliação Geriátrica , Humanos , Vida Independente , Masculino , Dor , Estudos Prospectivos , Fatores de RiscoRESUMO
OBJECTIVE: There is a two-way relationship between frailty and depression, but the mechanisms by which one may influence the other are not well understood. The objective of this study was to evaluate the relationship between psychosocial factors and frailty in community-dwelling aged populations with depression. DESIGN: Observational cross-sectional study. SITE: 5 primary care centres. PARTICIPANTS: Community-dwelling subjects with depression aged ≥70 years. MAIN MEASUREMENTS: Frailty status was established according to Fried criteria, depression and depression severity were evaluated by DSM-IV criteria and the Hamilton Depression Rating Scale, respectively, and psychosocial factors were assessed using the Gijón Social-Familial Evaluation Scale and ad hoc questionnaires. RESULTS: Recruited were 338 subjects (mean age 77.2 years), 82% women and 36.1% rated as frail. A dose-response relationship was observed between depression severity and frailty risk. Widowhood was a risk factor for frailty, while a higher educational level, home internet, stairs in the home, and an active social life had a protective effect. A multivariate analysis showed that age, number of drugs, and depression severity were independent risk factors for frailty, while an active social life was a protective factor. The severity of depressive symptoms showed higher association with frailty than other clinical and socio-demographic characteristics. CONCLUSIONS: In depressed elderly subjects, frailty is associated with psychologiocal factors such as the intensity of depressive symptoms and with social factors such as education level, widowhood, loneliness, and limited social life. More research is required to better understand the modifiable psychological risk factors for frailty.
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Fragilidade , Idoso , Estudos Transversais , Depressão/epidemiologia , Feminino , Idoso Fragilizado , Fragilidade/epidemiologia , Avaliação Geriátrica , Humanos , Vida Independente , MasculinoRESUMO
Since the coronavirus pandemic set in in Spain in March 2020, a noteworthy increase in the incidence of acute limb ischemia (ALI) has been observed. It has been recently discovered that SARS-CoV 2 may lead to ALI secondary to arterial thrombosis. Elevation of D-dimer (DD) in patients with coronavirus infection (COVID-19) indicates that a hypercoagulable state causes acute arterial thrombosis. A remarkably high DD elevation has been reported to be a poor prognosis factor in COVID-19. The ways in which SARS-CoV 2 results in arterial thrombosis may be multiple. On the other hand, surgical revascularization for ALI is associated with poor outcomes in COVID-19 patients, probably in relation to hypercoagulability. Here, we describe two ALI cases in patients who required urgent surgical treatment for limb salvage and were positive for the novel coronavirus infection (COVID 19).
Desde que a pandemia pelo novo coronavírus se estabeleceu na Espanha, em março de 2020, um aumento notável da incidência de isquemia aguda de membros foi observado. Recentemente, descobriu-se que o coronavírus 2 causador da síndrome respiratória aguda grave (SARS-CoV-2) pode ocasionar isquemia aguda de membros secundária à trombose arterial. A elevação do D-dímero em pacientes acometidos pela doença do novo coronavírus (COVID-19) indica o estado de hipercoagulabilidade como causa da trombose arterial aguda. Vale destacar que a alta elevação do D-dímero foi relatada como um fator de prognóstico reservado na COVID-19. Há diversas maneiras pelas quais o SARS-CoV-2 pode resultar em trombose arterial. Em pacientes com COVID-19, a revascularização cirúrgica para isquemia aguda de membros está associada a desfechos desfavoráveis, provavelmente relacionados a hipercoagulabilidade. Descrevemos dois casos de isquemia aguda de membros de pacientes que necessitaram de tratamento cirúrgico de urgência para salvamento de membro e que haviam testado positivo para COVID-19.
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Preclinical Research & Development Several clinically useful anticancer drugs selectively kill cancer cells by inducing DNA damage; the genomic instability and DNA repair defects of cancer cells make them more vulnerable than normal cells to the cytotoxicity of DNA-damaging agents. Because epoxide-containing compounds can induce DNA damage, we have used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to evaluate the selective cytotoxicity of three epoxyalkyl galactopyranosides against A549 lung cancer cells and MRC-5 lung normal cells. Compound (2S,3S)-2,3-epoxydecyl 4,6-O-(S)-benzylidene-ß-d-galactopyranoside (EDBGP) showed the highest selective anticancer activity and was selected for mechanistic studies. After observing that EDBGP induced cellular DNA damage (comet assay), we found that cells deficient in nucleotide excision repair were hypersensitive to the cytotoxicity of this compound; this suggests that EDBGP may induce bulky DNA adducts. EDBGP did not inhibit glycolysis (glucose consumption and lactate production). Pretreatment of lung cancer cells with several antioxidants did not reduce the cytotoxicity of EDBGP, thereby indicating that reactive oxygen species do not participate in the anticancer activity of this compound. Finally, EDBGP was screened against a panel of cancer cells and normal cells from several tissues, including three genetically modified skin fibroblasts with increasing degree of malignancy. Our results suggest that epoxyalkyl galactopyranosides are promising lead compounds for the development of new anticancer agents.
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Citotoxinas/química , Dano ao DNA/efeitos dos fármacos , Galactose/química , Galactose/toxicidade , Células A549 , Animais , Células CHO , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Cricetulus , Dano ao DNA/fisiologia , Relação Dose-Resposta a Droga , Feminino , Células HCT116 , Células HL-60 , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , MasculinoRESUMO
Decitabine (5-aza-2'-deoxycytidine, 5-azadC) is used in the treatment of Myelodysplatic syndrome (MDS) and Acute Myeloid Leukemia (AML). Its mechanism of action is thought to involve reactivation of genes implicated in differentiation and transformation, as well as induction of DNA damage by trapping DNA methyltranferases (DNMT) to DNA. We demonstrate for the first time that base excision repair (BER) recognizes 5-azadC-induced lesions in DNA and mediates repair. We find that BER (XRCC1) deficient cells are sensitive to 5-azadC and display an increased amount of DNA single- and double-strand breaks. The XRCC1 protein co-localizes with DNMT1 foci after 5-azadC treatment, suggesting a novel and specific role of XRCC1 in the repair of trapped DNMT1. 5-azadC-induced DNMT foci persist in XRCC1 defective cells, demonstrating a role for XRCC1 in repair of 5-azadC-induced DNA lesions. Poly (ADP-ribose) polymerase (PARP) inhibition prevents XRCC1 relocation to DNA damage sites, disrupts XRCC1-DNMT1 co-localization and thereby efficient BER. In a panel of AML cell lines, combining 5-azadC and Olaparib cause synthetic lethality. These data suggest that PARP inhibitors can be used in combination with 5-azadC to improve treatment of MDS and AML.
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Antimetabólitos Antineoplásicos/toxicidade , Azacitidina/análogos & derivados , Reparo do DNA/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Ftalazinas/farmacologia , Piperazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Azacitidina/toxicidade , Linhagem Celular Tumoral , Cricetinae , DNA (Citosina-5-)-Metiltransferases/análise , Adutos de DNA/metabolismo , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/análise , Decitabina , Humanos , Reparo de DNA por Recombinação , Proteína 1 Complementadora Cruzada de Reparo de Raio-XRESUMO
5-Aza-2'-deoxycytidine (5-azadC) is a DNA methyltransferase (DNMT) inhibitor increasingly used in treatments of hematological diseases and works by being incorporated into DNA and trapping DNMT. It is unclear what DNA lesions are caused by 5-azadC and if such are substrates for DNA repair. Here, we identify that 5-azadC induces DNA damage as measured by γ-H2AX and 53BP1 foci. Furthermore, 5-azadC induces radial chromosomes and chromatid breaks that depend on active replication, which altogether suggest that trapped DNMT collapses oncoming replication forks into double-strand breaks. We demonstrate that RAD51-mediated homologous recombination (HR) is activated to repair 5-azadC collapsed replication forks. Fanconi anemia (FA) is a rare autosomal recessive disorder, and deaths are often associated with leukemia. Here, we show that FANCG-deficient cells fail to trigger HR-mediated repair of 5-azadC-induced lesions, leading to accumulation of chromatid breaks and inter-chromosomal radial fusions as well as hypersensitivity to the cytotoxic effects of 5-azadC. These data demonstrate that the FA pathway is important to protect from 5-azadC-induced toxicity. Altogether, our data demonstrate that cytotoxicity of the epigenetic drug 5-azadC can, at least in part, be explained by collapsed replication forks requiring FA-mediated HR for repair.
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Azacitidina/análogos & derivados , Replicação do DNA/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Proteína do Grupo de Complementação G da Anemia de Fanconi/fisiologia , Reparo de DNA por Recombinação , Animais , Azacitidina/toxicidade , Linhagem Celular , Cromátides/efeitos dos fármacos , Cricetinae , Cricetulus , Quebras de DNA , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Decitabina , Leupeptinas/farmacologia , Inibidores de Proteassoma/farmacologiaRESUMO
Aneurysms of peripheral arteries are infrequent, with an incidence <1%. Dorsalis pedis artery (DPA) aneurysms are extremely rare, and most of them are pseudoaneurysms secondary to trauma or iatrogenic injuries. We report the first case of simultaneous (synchronous) bilateral DPA true aneurysms and how we repaired them. We review the literature on DPA true aneurysms and focus on the surgical management.
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Aneurisma/cirurgia , Pé/irrigação sanguínea , Procedimentos Cirúrgicos Vasculares , Idoso , Anastomose Cirúrgica , Aneurisma/diagnóstico por imagem , Aneurisma/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veia Safena/transplante , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Enxerto VascularRESUMO
Metatorbernite (Cu(UO(2))(2)(PO(4))(2)·8H(2)O) has been identified in contaminated sediments as a phase controlling the fate of U. Here, we applied atomic force microscopy (AFM) to observe in situ the interaction between metatorbernite cleavage surfaces and flowing aqueous solutions (residence time = 1 min) with different pHs. In contact with deionized water the features of (001) surfaces barely modify. However, changes are remarkable both under acidic and basic conditions. In acidic solutions (pH = 2.5) metatorbernite surface develops a rough altered layer and large pits nucleate on it. The altered layer shows a low adhesion and is removed by the AFM tip during the scanning. The large pits spread rapidly, at few tens of nm/s, indicating a collapse of the structure. The combination of dissolution and the presence of defects in the metatorbernite structure can explain both the collapse process and the alteration of the surfaces under acidic conditions. Other mechanisms such as ion exchange reactions remain speculative. In NaOH solutions (pH = 11.5) metatorbernite dissolves by formation of etch pits bounded by steps parallel to [100], the direction of the most straight periodic bond chains (PBCs) in metatorbernite structure. These steps retreat at â¼0.15 nm/s. Under these conditions dissolution is promoted by the formation of stable uranyl carbonate complexes in solution.
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Fosfatos/química , Compostos de Urânio/química , Água/química , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Soluções , Propriedades de SuperfícieRESUMO
BACKGROUND: Due to the complexities of advanced illnesses and their treatments, it can be difficult for patients in palliative care to maintain their quality of life. Telemedicine interventions in chronic disease management engage patients in their care, provide continuous follow-up by their health care providers, identify symptoms earlier, and allow a quick response to illness-related decline. OBJECTIVE: We aimed to detail and reflect on the design of an app and evaluate its feasibility to monitor the clinical situation of patients with advanced illnesses. METHODS: This study used a mixed methods design using qualitative methods to inform app development and design and quantitative methods for data collection and analysis of patient evaluations. Palliative care units in 2 Spanish university hospitals (Nuestra Señora de la Candelaria in Santa Cruz de Tenerife and University Hospital Complex of Ferrol in A Coruña) carried out a literature review, designed the study protocol, and obtained approval from the Ethics Committee from June to December 2020. In addition, focus group meetings were held, and the design and technical development of the app were elaborated on and subsequently presented in the participating palliative care units. From January to March 2021, the app was made public on the App Store and Play Store, and a pilot study with patients was carried out in April to September 2021. RESULTS: Six focus group meetings were held that included doctors, nurses, app developers, technology consultants, and sponsors. In addition, the technology consultants presented their results 3 times in the participating palliative care units to obtain feedback. After the app's final design, it was possible to publish it on the usual servers and begin its evaluation in patients (n=60, median age 72 years). Sixty percent (n=36) of the participants were women and 40% (n=24) were men. The most prevalent advanced pathology was cancer (n=46, 76%), followed by other diseases (n=7, 12%) and amyotrophic lateral sclerosis (n=5, 8%). Seventy percent (n=42) of the patients were already in follow-up prior to the start of the study, while 30% (n=18) were included at the start of their follow-up. The information in the app was collected and entered by relatives or caregivers in 60% (n=36) of the cases. The median follow-up was 52 (IQR 14-104) days. In all, 69% (n=41) had a follow-up >30 days (10 were deceased and 9 were missing data). The use of the different sections of the app ranged from 37% (n=22) for the glycemic record to 90% (n=54) for the constipation scale). Patients and caregivers were delighted with its ease of use and usefulness. CONCLUSIONS: Incorporating an intelligent remote patient monitoring system in clinical practice for patients in palliative care can improve access to health services and provide more information to professionals.
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BACKGROUND: Center-based cardiac rehabilitation programs (CRPs) reduce morbidity and mortality after an ischemic cardiac event; however, they are widely underused. Home-based CRP has emerged as an alternative to improve patient adherence; however, its safety and efficacy remain unclear, especially for older patients and female patients. OBJECTIVE: This study aimed to develop a holistic home-based CRP for patients with ischemic heart disease and evaluate its safety and impact on functional capacity, adherence to a healthy lifestyle, and quality of life. METHODS: The 8-week home-based CRP included patients of both sexes, with no age limit, who had overcome an acute myocardial infarction in the previous 3 months, had a left ventricular ejection fraction of ≥40%, and had access to a tablet or mobile device. The CRP was developed using a dedicated platform designed explicitly for this purpose and included 3 weekly exercise sessions combining tailored aerobic and strength training and 2 weekly educational session focused on lifestyle habits, therapeutic adherence, and patient empowerment. RESULTS: We initially included 62 patients, of whom 1 was excluded for presenting with ventricular arrhythmias during the initial stress test, 5 were excluded because of incompatibility, and 6 dropped out because of a technological barrier. Ultimately, 50 patients completed the program: 85% (42/50) were male, with a mean age of 58.9 (SD 10.3) years, a mean left ventricular ejection fraction of 52.1% (SD 6.72%), and 25 (50%) New York Heart Association functional class I and 25 (50%) New York Heart Association II-III. The CRP significantly improved functional capacity (+1.6 metabolic equivalent tasks), muscle strength (arm curl test +15.5% and sit-to-stand test +19.7%), weekly training volume (+803 metabolic equivalent tasks), adherence to the Mediterranean diet, emotional state (anxiety), and quality of life. No major complications occurred, and adherence was excellent (>80%) in both the exercise and educational sessions. In the subgroup analysis, CRP showed equivalent beneficial effects irrespective of sex and age. In addition, patient preferences for CRP approaches were equally distributed, with one-third (14/50, 29%) of the patients preferring a face-to-face CRP, one-third (17/50, 34%) preferring a telematic CRP, and one-third (18/50, 37%) preferring a hybrid approach. Regarding CRP duration, 63% (31/50) of the patients considered it adequate, whereas the remaining 37% (19/50) preferred a longer program. CONCLUSIONS: A holistic telematic CRP dedicated to patients after an ischemic cardiac event, irrespective of sex and age, is safe and, in our population, has achieved positive results in improving maximal aerobic capacity, weekly training volume, muscle strength, quality of life, compliance with diet, and anxiety symptoms. The preference for a center- or home-based CRP approach is diverse among the study population, emphasizing the need for a tailored CRP to improve adherence and completion rates.
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INTRODUCTION: Glucocorticoids are associated with serious side effects related to dosing and time of use. Unfortunately, there is no standard method for determining glucocorticoid exposure, especially in patients undergoing long-term treatment. OBJECTIVE: The aim of this work was to create a free and easy-to-use web application to calculate, in a systematic way, the total cumulative dose of corticosteroids. METHODS: The total cumulative dose is calculated as the sum of all periods of treatment with different doses of corticosteroids, and is expressed as the equivalent dose of prednisone in mg. Glucocorticoid doses during periods in which the available information is missing or incomplete are estimated by systematic assumptions. RESULTS: A simulation exercise using standard patterns of steroid use in polymyalgia rheumatica, and giant cell arteritis showed that even when the period of no information reached 50% of the time, the accuracy of the calculator had a mean absolute percentage error (MAPE)<7%. CONCLUSION: This tool simplifies and standardizes the glucocorticoids cumulative dose calculation, thereby minimizing bias in the assessment of glucocorticoid cumulative dose.
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Arterite de Células Gigantes , Polimialgia Reumática , Humanos , Glucocorticoides/uso terapêutico , Prednisona/efeitos adversos , Arterite de Células Gigantes/tratamento farmacológico , Polimialgia Reumática/tratamento farmacológicoRESUMO
In the last years a number of reports have shown that the so-called topoisomerase II (topo II) catalytic inhibitors are able to induce DNA and chromosome damage, an unexpected result taking into account that they do not stabilize topo II-DNA cleavable complexes, a feature of topo II poisons such as etoposide and amsacrine. Merbarone inhibits the catalytic activity of topo II by blocking DNA cleavage by the enzyme. While it was first reported that merbarone does not induce genotoxic effects in mammalian cells, this has been challenged by reports showing that the topo II inhibitor induces efficiently chromosome and DNA damage, and the question as to a possible behavior as a topo II poison has been put forward. Given these contradictory results, and the as yet incomplete knowledge of the molecular mechanism of action of merbarone, in the present study we have tried to further characterize the mechanism of action of merbarone on cell proliferation, cell cycle, as well as chromosome and DNA damage in cultured CHO cells. Merbarone was cytotoxic as well as genotoxic, inhibited topo II catalytic activity, and induced endoreduplication. We have also shown that merbarone-induced DNA damage depends upon ongoing DNA synthesis. Supporting this, inhibition of DNA synthesis causes reduction of DNA damage and increased cell survival.
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Dano ao DNA/efeitos dos fármacos , Endorreduplicação/efeitos dos fármacos , Tiobarbitúricos/toxicidade , Inibidores da Topoisomerase II/toxicidade , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cricetinae , CricetulusRESUMO
The high incidence of colorectal cancer (CRC) in developed countries indicates a predominant role of the environment as a causative factor. Natural gut microbiota provides multiple benefits to humans. Dysbiosis is characterized by an unbalanced microbiota and causes intestinal damage and inflammation. The latter is a common denominator in many cancers including CRC. Indeed, in an inflammation scenario, cellular growth is promoted and immune cells release Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS), which cause DNA damage. Apart from that, many metabolites from the diet are converted into DNA damaging agents by microbiota and some bacteria deliver DNA damaging toxins in dysbiosis conditions as well. The interactions between diet, microbiota, inflammation, and CRC are not the result of a straightforward relationship, but rather a network of multifactorial interactions that deserve deep consideration, as their consequences are not yet fully elucidated. In this paper, we will review the influence of dysbiosis in the induction of DNA damage and CRC.
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Neoplasias Colorretais/genética , Dano ao DNA , Reparo do DNA , Disbiose/complicações , Microbioma Gastrointestinal , Inflamação/complicações , Neoplasias Colorretais/etiologia , DNA de Neoplasias/metabolismo , Dieta , HumanosRESUMO
The design and preparation of novel nanocarriers to transport cancer drugs for chemotherapy purposes is an important line of research in the medical field. A new 5-fluorouracil (5-Fu) transporter was designed based on the use of two new biocompatible gold nanosystems: (i) a gold nanoparticle precursor, Au@16-Ph-16, stabilized with the positively charged gemini surfactant 16-Ph-16, and (ii) the compacted nanocomplexes formed by the precursor and DNA/5-Fu complexes, Au@16-Ph-16/DNA-5-Fu. The physicochemical properties of the obtained nanosystems were studied by using UV-visible spectroscopy, TEM, dynamic light scattering, and zeta potential techniques. Method tuning also requires the use of circular dichroism, atomic force microscopy, and fluorescence spectroscopy techniques for the prior selection of the optimal relative Au@16-Ph-16 and DNA concentrations (R = CAu@16-Ph-16/CDNA), biopolymer compaction/decompaction, and 5-Fu release from the DNA/5-Fu complex. TEM experiments revealed the effective internalization of the both precursor and Au@16-Ph-16/DNA-5-Fu-compacted nanosystems into the cells. Moreover, cytotoxicity assays and internalization experiments using TEM and confocal microscopy showed that the new strategy for 5-Fu administration enhanced efficacy, biocompatibility and selectivity against lung cancer cells. The differential uptake among different formulations is discussed in terms of the physicochemical properties of the nanosystems.
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We recently screened a series of new aziridines ß-D-galactopyranoside derivatives for selective anticancer activity and identified 2-methyl-2,3-[N-(4-methylbenzenesulfonyl)imino]propyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-ß-D-galactopyranoside (AzGalp) as the most promising compound. In this article, we explore the possible mechanisms involved in the cytotoxicity of this aziridine and evaluate its selective anticancer activity using cancer cells and normal cells from a variety of tissues. Our data show that AzGalp induces DNA damage (comet assay). Cells deficient in the nucleotide excision repair (NER) pathway were hypersensitive to the cytotoxicity of this compound. These results suggest that AzGalp induces bulky DNA adducts, and that cancer cells lacking a functional NER pathway may be particularly vulnerable to the anticancer effects of this aziridine. Several experiments revealed that neither the generation of oxidative stress nor the inhibition of glycolysis played a significant role in the cytotoxicity of AzGalp. Combinations of AzGalp with oxaliplatin or 5-fluorouracil slightly improved the ability of both anticancer drugs to selectively kill cancer cells. AzGalp also showed selective cytotoxicity against a panel of malignant cells versus normal cells; the highest selectivity was observed for two acute promyelocytic leukemia cell lines. Additional preclinical studies are necessary to evaluate the anticancer potential of AzGalp.
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Catenations between sister chromatids result from DNA replication and must be resolved to ensure proper chromatid segregation in mitosis. Functionally active Topoisomerase II (Topo II), through its mechanism of concerted breaking and rejoining of double stranded DNA, is required to carry out this fundamental process. In previous studies we have shown that modifications in DNA sequence by halogenated pyrimidines and by the demethylating agent 5-azacytidine leads to malfunction of Topo II that results in an increased yield of endorreduplicated cells as a result of segregation failure. In the present work we have evaluated the possible influence of the methylating agent Budesonide to modify the frequency of endoreduplicated cells in AA8 Chinese hamster cell population. Our results seem to indicate that when Budesonide was administered for two consecutive cell cycles did induce an increase in the yield of endoreduplicated cells, as previously observed for the hypomethylating agent 5-azaC. We have also examined the possible relationship between extensive hypermethylation induced by Budesonide in DNA and stabilization of cleavable complexes by m-AMSA. Taken as a whole, our results show that the degree of methylation in DNA correlates with the effectiveness of m-AMSA to stabilize the Topo II-DNA complexes and to induce DNA cleavage. These findings evidence for the first time the functional importance of DNA hyper- and hypomethylation changes as epigenetic factors able to modulate Topo II activity for proper chromosome segregation.
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Budesonida/farmacologia , Metilação de DNA , DNA Topoisomerases Tipo II/genética , Animais , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Ciclo Celular , Núcleo Celular/metabolismo , Cromossomos/ultraestrutura , Cricetinae , Replicação do DNA , Citometria de Fluxo/métodos , Glucocorticoides/farmacologia , Humanos , Microscopia de Fluorescência/métodos , MitoseRESUMO
BACKGROUND: Monitoring mental health outcomes has traditionally been based on heuristic decisions, often based on scarce, subjective evidence, making the clinical decisions made by professionals, as well as the monitoring of these diseases, subject to flaws. However, the digital phenotype, which refers to the analysis of data collected by measuring human behavior with mobile sensors and smart bracelets, is a promising tool for filling this gap in current clinical practice. OBJECTIVE: The objectives of this study are to develop the digital phenotyping of patients with alcohol use disorder and anxiety symptoms using data collected from a mobile device (ie, smartphone) and a wearable sensor (ie, Fitbit) and to analyze usability and patient satisfaction with the data collection service provided by the app. METHODS: We propose to conduct a study among a group of 60 participants split into two subgroups-experimental and control-of 30 participants each. The experimental group will be recruited by physicians from the Hospital Clínic de Barcelona, and the control group will be recruited on a volunteer basis through fliers and social media. All participants will go through pretraining to ensure technological capability and understanding of tasks, then each participant will download the HumanITcare app and will be given a wearable sensor (ie, Fitbit). Throughout the 4-month period, participants will be monitored on a range of factors, including sleep cycle, heart rate, movement patterns, and sociability. All data from the wearable sensors and the mobile devices will be saved and sent to the HumanITcare server. Participants will be asked to complete weekly questionnaires about anxiety, depression, and alcohol use disorder symptoms. Research assistants will ensure timely responses. The data from both sensors will then be compared to the questionnaire responses to determine how accurately the devices can predict the same symptoms. RESULTS: The recruitment phase was completed in November 2019 and all the data were collected by the end of December 2019. Data are being processed; this process is expected to be completed by October 2020. CONCLUSIONS: This study was created and conducted as a pilot study with the Hospital Clínic de Barcelona, with the purpose of exploring the feasibility of our approach. The study is focused on patients diagnosed with anxiety and alcohol use disorder, but participants were also monitored for depressive symptoms throughout the trial, although these were not part of the initial inclusion criteria. A limitation to our study was the exclusive use of Android smartphones over iOS devices; this could result in a potential selection bias, due to the accessibility and affordability of Android phones as opposed to iOS-based phones. Another limitation might be that reviews of usability and satisfaction could be confounded by factors such as age and familiarity. An additional function that we might add in future studies is the ability for patients to manage their own data. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/16964.
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Rutile, a common accessory mineral in a wide variety of rocks, is the most stable naturally occurring TiO2 polymorph. The relationship between its trace element composition and formation conditions has provided geoscientists with discriminant tools for fingerprinting geological processes, such as magmatic evolution and subduction zone metamorphism, alongside applications to the study of sediment provenance. In the present work, volcaniclastic rock samples belonging to Fara and Saiq Formations, outcropping in Jebel Akhdar mountains, Oman, are studied with Raman spectroscopy and Electron Microprobe (EMP) aiming: of (i) the identification of different naturally-occurring TiO2 polymorphs, (ii) the evaluation of their trace element contents in relation with hydrothermal alteration features, and (iii) the analysis of the mineral reactive pathways behind the observed textural relationships. Raman investigations demonstrated that interstitial, fine-grained TiO2 corresponds to anatase, whereas rutile occurs as isolated single grains. EMP determinations further revealed that an identified Nb-enrichment in anatase is coupled with a corresponding Nb-depletion in rutile. The combination of the obtained results with petrographic observations enabled unravelling the TiO2 reactive pathways affecting the studied samples. Thus, a coupled polymorphic dissolution-precipitation reaction assisting rutile-to-anatase conversion has been defined, together with the role of Nb in further stabilizing the structure of the lower temperature polymorph. Semi-quantitative thermometric considerations suggest that rutile substrates are likely of magmatic origin, whereas anatase formation is clearly associated with a lower temperature aqueous environment. The gathered results raise fundamental questions concerning the application of commonly used rutile-based geochemical and thermometric tools.
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Aneugenic compounds are able to cause chromosome missegregation during mitosis which results in aneuploidy in cells that are able to survive. Aneuploidy is considered a key early condition in the progression from a normal cell into a cancerous cell. The possible toxicity of therapeutic lithium has raised concern because lithium salts are currently widely prescribed as an efficient treatment of manic-depressive disorders and numerous undesirable side effects of long-term treatment have been reported to date. We have observed a dose-dependent cytotoxic effect of both Li2CO3 and LiCl in AA8 CHO cells, while no genotoxic damage was detected. Mitotic abnormalities such as multipolar anaphases and lagging chromosomes leading to the presence of micronuclei in the next interphase were frequently observed after treatment with lithium salts. Thus, the effectiveness of both lithium salts to induce alterations in the normal segregation of chromosomes could be ascribed to interference with proteins involved in the organization and/or function of the mitotic apparatus.
Assuntos
Aneugênicos/toxicidade , Aneuploidia , Antimaníacos/toxicidade , Carbonato de Lítio/toxicidade , Cloreto de Lítio/toxicidade , Mitose/efeitos dos fármacos , Animais , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Dano ao DNA , Relação Dose-Resposta a Droga , Micronúcleos com Defeito Cromossômico/induzido quimicamenteRESUMO
Tea polyphenols are promising chemopreventive anticancer agents, the properties of which have been studied both in vitro and in vivo, providing evidence that - within this group of compounds - the tea flavanols are able to inhibit carcinogenesis, an effect that in some cases could be correlated with increased cell apoptosis and decreased cell proliferation. Of four main tea flavanols, namely (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), (+)-catechin (CA) and (-)-epicatechin (EC), it was found that EGCG was the most potent to inhibit dose dependently the topoisomerase II (TOPO II) catalytic activity isolated from hamster ovary AA8 cells. In the range of concentrations that caused TOPO II inhibition, a high level of endoreduplication, a rare phenomenon that consists in two successive rounds of DNA replication without intervening mitosis, was observed, while neither micronuclei nor DNA strand breaks (Comet assay) were detected at the same doses. We propose that the anticarcinogenic effect of tea flavanols can be partly explained by their potency and effectiveness to induce endoreduplication. Concerning such an induction, maximum effect seems to require a pyrogallol structure at the B-ring. Additional substitution with a galloylic residue at the C3 hydroxyl group leads to further augmentation of the effect. Thus, we suggest that the chemopreventive properties of tea flavanols can be at least partly due to their ability to interfere with the cell cycle and block cell proliferation at early stages of mitosis.