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1.
Nucleic Acids Res ; 51(11): 5396-5413, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-36971114

RESUMO

The deubiquitinating enzyme Ataxin-3 (ATXN3) contains a polyglutamine (PolyQ) region, the expansion of which causes spinocerebellar ataxia type-3 (SCA3). ATXN3 has multiple functions, such as regulating transcription or controlling genomic stability after DNA damage. Here we report the role of ATXN3 in chromatin organization during unperturbed conditions, in a catalytic-independent manner. The lack of ATXN3 leads to abnormalities in nuclear and nucleolar morphology, alters DNA replication timing and increases transcription. Additionally, indicators of more open chromatin, such as increased mobility of histone H1, changes in epigenetic marks and higher sensitivity to micrococcal nuclease digestion were detected in the absence of ATXN3. Interestingly, the effects observed in cells lacking ATXN3 are epistatic to the inhibition or lack of the histone deacetylase 3 (HDAC3), an interaction partner of ATXN3. The absence of ATXN3 decreases the recruitment of endogenous HDAC3 to the chromatin, as well as the HDAC3 nuclear/cytoplasm ratio after HDAC3 overexpression, suggesting that ATXN3 controls the subcellular localization of HDAC3. Importantly, the overexpression of a PolyQ-expanded version of ATXN3 behaves as a null mutant, altering DNA replication parameters, epigenetic marks and the subcellular distribution of HDAC3, giving new insights into the molecular basis of the disease.


Assuntos
Ataxina-3 , Cromatina , Replicação do DNA , Humanos , Ataxina-3/genética , Ataxina-3/metabolismo , Cromatina/genética , Dano ao DNA , Doença de Machado-Joseph/genética , Proteínas Repressoras/metabolismo
2.
Mol Cell ; 64(4): 704-719, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27871366

RESUMO

The cytotoxicity of DNA-protein crosslinks (DPCs) is largely ascribed to their ability to block the progression of DNA replication. DPCs frequently occur in cells, either as a consequence of metabolism or exogenous agents, but the mechanism of DPC repair is not completely understood. Here, we characterize SPRTN as a specialized DNA-dependent and DNA replication-coupled metalloprotease for DPC repair. SPRTN cleaves various DNA binding substrates during S-phase progression and thus protects proliferative cells from DPC toxicity. Ruijs-Aalfs syndrome (RJALS) patient cells with monogenic and biallelic mutations in SPRTN are hypersensitive to DPC-inducing agents due to a defect in DNA replication fork progression and the inability to eliminate DPCs. We propose that SPRTN protease represents a specialized DNA replication-coupled DPC repair pathway essential for DNA replication progression and genome stability. Defective SPRTN-dependent clearance of DPCs is the molecular mechanism underlying RJALS, and DPCs are contributing to accelerated aging and cancer.


Assuntos
Reparo do DNA , Replicação do DNA , Proteínas de Ligação a DNA/metabolismo , DNA/química , Instabilidade Genômica , Sequência de Aminoácidos , Sítios de Ligação , Reagentes de Ligações Cruzadas/química , DNA/genética , DNA/metabolismo , Dano ao DNA , Proteínas de Ligação a DNA/genética , Etoposídeo/química , Formaldeído/química , Expressão Gênica , Humanos , Cinética , Mutação , Ligação Proteica , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Síndrome , Raios Ultravioleta
3.
EMBO J ; 38(21): e102361, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31613024

RESUMO

The E3 ubiquitin ligase RNF8 (RING finger protein 8) is a pivotal enzyme for DNA repair. However, RNF8 hyper-accumulation is tumour-promoting and positively correlates with genome instability, cancer cell invasion, metastasis and poor patient prognosis. Very little is known about the mechanisms regulating RNF8 homeostasis to preserve genome stability. Here, we identify the cellular machinery, composed of the p97/VCP ubiquitin-dependent unfoldase/segregase and the Ataxin 3 (ATX3) deubiquitinase, which together form a physical and functional complex with RNF8 to regulate its proteasome-dependent homeostasis under physiological conditions. Under genotoxic stress, when RNF8 is rapidly recruited to sites of DNA lesions, the p97-ATX3 machinery stimulates the extraction of RNF8 from chromatin to balance DNA repair pathway choice and promote cell survival after ionising radiation (IR). Inactivation of the p97-ATX3 complex affects the non-homologous end joining DNA repair pathway and hypersensitises human cancer cells to IR. We propose that the p97-ATX3 complex is the essential machinery for regulation of RNF8 homeostasis under both physiological and genotoxic conditions and that targeting ATX3 may be a promising strategy to radio-sensitise BRCA-deficient cancers.


Assuntos
Adenosina Trifosfatases/metabolismo , Ataxina-3/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Homeostase , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Adenosina Trifosfatases/genética , Ataxina-3/genética , Sobrevivência Celular , Cromatina/genética , Proteínas de Ligação a DNA/genética , Instabilidade Genômica , Células HEK293 , Células HeLa , Humanos , Proteínas Nucleares/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Transdução de Sinais , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
4.
Oncologist ; 28(10): 901-910, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37120291

RESUMO

BACKGROUND: Older patients with myelodysplastic syndromes (MDS), particularly those with no or one cytopenia and no transfusion dependence, typically have an indolent course. Approximately, half of these receive the recommended diagnostic evaluation (DE) for MDS. We explored factors determining DE in these patients and its impact on subsequent treatment and outcomes. PATIENTS AND METHODS: We used 2011-2014 Medicare data to identify patients ≥66 years of age diagnosed with MDS. We used Classification and Regression Tree (CART) analysis to identify combinations of factors associated with DE and its impact on subsequent treatment. Variables examined included demographics, comorbidities, nursing home status, and investigative procedures performed. We conducted a logistic regression analysis to identify correlates associated with receipt of DE and treatment. RESULTS: Of 16 851 patients with MDS, 51% underwent DE. patients with MDS with no cytopenia (n = 3908) had the lowest uptake of DE (34.7%). Compared to patients with no cytopenia, those with any cytopenia had nearly 3 times higher odds of receiving DE [adjusted odds ratio (AOR), 2.81: 95% CI, 2.60-3.04] and the odds were higher for men than for women [AOR, 1.39: 95%CI, 1.30-1.48] and for Non-Hispanic Whites [vs. everyone else (AOR, 1.17: 95% CI, 1.06-1.29)]. The CART showed DE as the principal discriminating node, followed by the presence of any cytopenia for receiving MDS treatment. The lowest percentage of treatment was observed in patients without DE, at 14.6%. CONCLUSION: In this select older patients with MDS, we identified disparities in accurate diagnosis by demographic and clinical factors. Receipt of DE influenced subsequent treatment but not survival.


Assuntos
Anemia , Síndromes Mielodisplásicas , Masculino , Humanos , Feminino , Idoso , Estados Unidos/epidemiologia , Medicare , Síndromes Mielodisplásicas/terapia , Síndromes Mielodisplásicas/tratamento farmacológico , Comorbidade
5.
Curr Oncol Rep ; 25(6): 539-547, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36928826

RESUMO

PURPOSE OF REVIEW: This article summarizes the current knowledge about clonal hematopoiesis of indeterminate potential (CHIP), its association with cardiovascular disease (CVD), and other outcomes, pathogenesis, postulated mechanisms of various pathologies, current knowledge gaps, possible targets of intervention, and therapeutic implications. RECENT FINDINGS: Recently, a common age-related hematological entity known as CHIP has been identified as the independent risk factor for CVD. CHIP is defined as the presence of clonally expanded blood cells involving leukemogenic mutations without the evidence of malignancy. CHIP is known to increase the inflammatory state which in turn is thought to be responsible for increased risk of CVD. Apart from CVD and malignancy, CHIP is also associated with pulmonary embolism, COPD, CKD, stroke, altered metabolism, obesity, liver disease, and increased all-cause mortality. At the same time surprisingly, CHIP is found to have positive outcomes in bone marrow transplant patients and similar reciprocal association with Alzheimer's disease. The risk of CVD and cancer increases with the advancing age, and these two are the leading causes of death in the USA. CHIP is an independent risk factor for CVD development. Most patients with CHIP have somatic clonal mutations in epigenetic regulators, DNA repair genes, or regulatory tyrosine kinases without evidence of overt hematological malignancy. CHIP portends increased risk for leukemia development and carries twofold increased risk of CVD including CAD, MI, and poor prognosis in heart failure. CHIP is associated with various other pathologies making CHIP an area of active research interest in recent years. Current research efforts aim to bridge many knowledge gaps in understanding of CHIP that still exist.


Assuntos
Doenças Cardiovasculares , Leucemia , Neoplasias , Humanos , Hematopoiese Clonal , Hematopoese/genética , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Neoplasias/genética , Mutação
6.
Sensors (Basel) ; 23(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37896481

RESUMO

Glaciers and snow are critical components of the hydrological cycle in the Himalayan region, and they play a vital role in river runoff. Therefore, it is crucial to monitor the glaciers and snow cover on a spatiotemporal basis to better understand the changes in their dynamics and their impact on river runoff. A significant amount of data is necessary to comprehend the dynamics of snow. Yet, the absence of weather stations in inaccessible locations and high elevation present multiple challenges for researchers through field surveys. However, the advancements made in remote sensing have become an effective tool for studying snow. In this article, the snow cover area (SCA) was analysed over the Beas River basin, Western Himalayas for the period 2003 to 2018. Moreover, its sensitivity towards temperature and precipitation was also analysed. To perform the analysis, two datasets, i.e., MODIS-based MOYDGL06 products for SCA estimation and the European Centre for Medium-Range Weather Forecasts (ECMWF) Atmospheric Reanalysis of the Global Climate (ERA5) for climate data were utilized. Results showed an average SCA of ~56% of its total area, with the highest annual SCA recorded in 2014 at ~61.84%. Conversely, the lowest annual SCA occurred in 2016, reaching ~49.2%. Notably, fluctuations in SCA are highly influenced by temperature, as evidenced by the strong connection between annual and seasonal SCA and temperature. The present study findings can have significant applications in fields such as water resource management, climate studies, and disaster management.

7.
Alzheimers Dement ; 19(4): 1117-1134, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36574591

RESUMO

INTRODUCTION: Plasma amyloid beta (Aß)1-42/Aß1-40 ratio, phosphorylated-tau181 (p-tau181), glial fibrillary acidic protein (GFAP), and neurofilament light (NfL) are putative blood biomarkers for Alzheimer's disease (AD). However, head-to-head cross-sectional and longitudinal comparisons of the aforementioned biomarkers across the AD continuum are lacking. METHODS: Plasma Aß1-42, Aß1-40, p-tau181, GFAP, and NfL were measured utilizing the Single Molecule Array (Simoa) platform and compared cross-sectionally across the AD continuum, wherein Aß-PET (positron emission tomography)-negative cognitively unimpaired (CU Aß-, n = 81) and mild cognitive impairment (MCI Aß-, n = 26) participants were compared with Aß-PET-positive participants across the AD continuum (CU Aß+, n = 39; MCI Aß+, n = 33; AD Aß+, n = 46) from the Australian Imaging, Biomarker & Lifestyle Flagship Study of Ageing (AIBL) cohort. Longitudinal plasma biomarker changes were also assessed in MCI (n = 27) and AD (n = 29) participants compared with CU (n = 120) participants. In addition, associations between baseline plasma biomarker levels and prospective cognitive decline and Aß-PET load were assessed over a 7 to 10-year duration. RESULTS: Lower plasma Aß1-42/Aß1-40 ratio and elevated p-tau181 and GFAP were observed in CU Aß+, MCI Aß+, and AD Aß+, whereas elevated plasma NfL was observed in MCI Aß+ and AD Aß+, compared with CU Aß- and MCI Aß-. Among the aforementioned plasma biomarkers, for models with and without AD risk factors (age, sex, and apolipoprotein E (APOE) ε4 carrier status), p-tau181 performed equivalent to or better than other biomarkers in predicting a brain Aß-/+ status across the AD continuum. However, for models with and without the AD risk factors, a biomarker panel of Aß1-42/Aß1-40, p-tau181, and GFAP performed equivalent to or better than any of the biomarkers alone in predicting brain Aß-/+ status across the AD continuum. Longitudinally, plasma Aß1-42/Aß1-40, p-tau181, and GFAP were altered in MCI compared with CU, and plasma GFAP and NfL were altered in AD compared with CU. In addition, lower plasma Aß1-42/Aß1-40 and higher p-tau181, GFAP, and NfL were associated with prospective cognitive decline and lower plasma Aß1-42/Aß1-40, and higher p-tau181 and GFAP were associated with increased Aß-PET load prospectively. DISCUSSION: These findings suggest that plasma biomarkers are altered cross-sectionally and longitudinally, along the AD continuum, and are prospectively associated with cognitive decline and brain Aß-PET load. In addition, although p-tau181 performed equivalent to or better than other biomarkers in predicting an Aß-/+ status across the AD continuum, a panel of biomarkers may have superior Aß-/+ status predictive capability across the AD continuum. HIGHLIGHTS: Area under the curve (AUC) of p-tau181 ≥ AUC of Aß42/40, GFAP, NfL in predicting PET Aß-/+ status (Aß-/+).  AUC of Aß42/40+p-tau181+GFAP panel ≥ AUC of Aß42/40/p-tau181/GFAP/NfL for Aß-/+.  Longitudinally, Aß42/40, p-tau181, and GFAP were altered in MCI versus CU.  Longitudinally, GFAP and NfL were altered in AD versus CU.  Aß42/40, p-tau181, GFAP, and NfL are associated with prospective cognitive decline.  Aß42/40, p-tau181, and GFAP are associated with increased PET Aß load prospectively.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides , Proteína Glial Fibrilar Ácida , Estudos Transversais , Filamentos Intermediários , Estudos Longitudinais , Estudos Prospectivos , Austrália , Apolipoproteína E4 , Disfunção Cognitiva/diagnóstico por imagem , Biomarcadores , Proteínas tau
8.
Alzheimers Dement ; 19(7): 2790-2804, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36576155

RESUMO

BACKGROUND: Glial fibrillary acidic protein (GFAP) is a promising candidate blood-based biomarker for Alzheimer's disease (AD) diagnosis and prognostication. The timing of its disease-associated changes, its clinical correlates, and biofluid-type dependency will influence its clinical utility. METHODS: We evaluated plasma, serum, and cerebrospinal fluid (CSF) GFAP in families with autosomal dominant AD (ADAD), leveraging the predictable age at symptom onset to determine changes by stage of disease. RESULTS: Plasma GFAP elevations appear a decade before expected symptom onset, after amyloid beta (Aß) accumulation and prior to neurodegeneration and cognitive decline. Plasma GFAP distinguished Aß-positive from Aß-negative ADAD participants and showed a stronger relationship with Aß load in asymptomatic than symptomatic ADAD. Higher plasma GFAP was associated with the degree and rate of neurodegeneration and cognitive impairment. Serum GFAP showed similar relationships, but these were less pronounced for CSF GFAP. CONCLUSION: Our findings support a role for plasma GFAP as a clinical biomarker of Aß-related astrocyte reactivity that is associated with cognitive decline and neurodegeneration. HIGHLIGHTS: Plasma glial fibrillary acidic protein (GFAP) elevations appear a decade before expected symptom onset in autosomal dominant Alzheimer's disease (ADAD). Plasma GFAP was associated to amyloid positivity in asymptomatic ADAD. Plasma GFAP increased with clinical severity and predicted disease progression. Plasma and serum GFAP carried similar information in ADAD, while cerebrospinal fluid GFAP did not.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Biomarcadores/líquido cefalorraquidiano , Cognição , Proteína Glial Fibrilar Ácida , Tomografia por Emissão de Pósitrons , Proteínas tau/líquido cefalorraquidiano
9.
Int J Mol Sci ; 24(10)2023 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-37240085

RESUMO

Molecules involved in drug resistance can be targeted for better therapeutic efficacies. Research on midkine (MDK) has escalated in the last few decades, which affirms a positive correlation between disease progression and MDK expression in most cancers and indicates its association with multi-drug resistance in cancer. MDK, a secretory cytokine found in blood, can be exploited as a potent biomarker for the non-invasive detection of drug resistance expressed in various cancers and, thereby, can be targeted. We summarize the current information on the involvement of MDK in drug resistance, and transcriptional regulators of its expression and highlight its potential as a cancer therapeutic target.


Assuntos
Terapia de Alvo Molecular , Neoplasias , Humanos , Midkina , Citocinas/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Resistencia a Medicamentos Antineoplásicos/genética
10.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203655

RESUMO

There has been a widespread adoption of hypomethylating agents (HMA: 5-Azacytidine (5-Aza)/decitabine) and venetoclax (Ven) for the treatment of acute myeloid leukemia (AML); however, the mechanisms behind the combination's synergy are poorly understood. Monotherapy often encounters resistance, leading to suboptimal outcomes; however, the combination of HMA and Ven has demonstrated substantial improvements in treatment responses. This study elucidates multiple synergistic pathways contributing to this enhanced therapeutic effect. Key mechanisms include HMA-mediated downregulation of anti-apoptotic proteins, notably MCL-1, and the priming of cells for Ven through the induction of genes encoding pro-apoptotic proteins such as Noxa. Moreover, Ven induces sensitization to HMA, induces overcoming resistance by inhibiting the DHODH enzyme, and disrupts antioxidant pathways (Nrf2) induced by HMA. The combination further disrupts oxidative phosphorylation in leukemia stem cells, amplifying the therapeutic impact. Remarkably, clinical studies have revealed a favorable response, particularly in patients harboring specific mutations, such as IDH1/2, NPM1, CEBPA, or ASXL1. This prompts future studies to explore the nuanced underpinnings of these synergistic mechanisms in AML patients with these molecular signatures.


Assuntos
Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Humanos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Regulação para Baixo , Azacitidina , Leucemia Mieloide Aguda/tratamento farmacológico
11.
Environ Geochem Health ; 45(5): 2291-2308, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35939248

RESUMO

A detailed study of heavy metals in the road dust of a mineral rich zone of Jharkhand state, India is reported herein. Metal concentrations in the road dust exceeded the corresponding values in the average shale as well as world average of soil. Metal pollution due to the road dust and the possible health impact arising there from was appraised through a number of indices such as Geo-accumulation Index (Igeo), Pollution Load Index, Enrichment Factor (EF), Contamination Factor and US EPA Hazard Index and Cancer Risk. Cu contamination was highest as per EF and Igeo, followed by Pb and Zn. Aggravated heavy metal loading in the road dust was conspicuous in the proximity of copper mines and processing units. Both geogenic and anthropogenic sources were responsible for heavy metals in road dust according to principal component analysis. Hazard Quotient, Hazard Index and Cancer Risk were calculated to ascertain non-carcinogenic and carcinogenic health risks in adults and children. Local inhabitants, particularly children, were under appreciable cancer and non-cancer risk. Oral ingestion was the major pathway for risk to the local commuters followed by dermal pathway. Present study underscored the importance of regular heavy metal monitoring of road dust in this zone and administer proactive road dust management practices to reduce metal pollution.


Assuntos
Poeira , Metais Pesados , Adulto , Criança , Humanos , Poeira/análise , Monitoramento Ambiental , Medição de Risco , Metais Pesados/toxicidade , Metais Pesados/análise , Minerais/análise , Índia/epidemiologia , Cidades , China
12.
J Anaesthesiol Clin Pharmacol ; 39(2): 195-200, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37564834

RESUMO

Background and Aims: Increased pain and associated stiffness hinders the advantages of exercise and process of recovery in primary adhesive capsulitis. We hypothesized that suprascapular nerve block may positively affect the outcome due to its role in pain relief of acute or chronic shoulder pain. We compared the effect of suprascapular nerve block and exercise with only exercise on the recovery of primary adhesive capsulitis. Material and Methods: A total of 96 patients of both sexes presenting with primary adhesive capsulitis were divided by computer randomization in two equal groups (n = 48). Group A received exercise only and Group B received suprascapular nerve block followed by exercise. Oral paracetamol was given for analgesia as desired. Patients were followed up at 4, 8, 16, and 24 weeks. Pain was assessed by visual analog scale; functional outcome by Shoulder Pain and Disability Index and range of movement by goniometer. Results: The pain scores and Shoulder Pain and Disability Index scores were significantly lower at all observation points of 4, 8,16, and 24 weeks in Group B than Group A (P < 0.05). The range of movement in all the ranges of forward flexion, extension, internal and external rotation, and abduction at all observation points was significantly higher in Group-B (P < 0.05) compared to Group A. The consumption of analgesics was significantly more in Group A than Group B at 4 and 8 weeks (P = 0.020 and P = 0.044) but comparable at 12 and 24 weeks (P = 0.145 and P = 0.237 respectively). Conclusion: Combining SSNB with exercise is more effective in treatment of primary adhesive capsulitis than exercise alone and reduces the use of analgesics. SSNB it is effective and safe to use in primary adhesive capsulitis.

13.
Phys Chem Chem Phys ; 24(18): 11066-11078, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35471404

RESUMO

Pseudocapacitors offer both high energy and high power, making them suitable for grid-scale electrochemical energy storage to harness renewable energy produced from sun, wind, and tides. To overcome performance degradation in terms of cycling fading and lower specific capacitance values at high charge/discharge rates of electrochemical pseudocapacitors based on transition-metal oxides, perovskite-structured SrFeO3-δ was envisaged as a negative electrode that harnesses the Fe4+/3+ and Fe3+/2+ redox couple to deliver superior performance. SrFeO3-δ offers high specific capacitances of ca. 733 F g-1 at a scan rate of 1 mV s-1 and ca. 743 F g-1 at a current density of 1 A g-1 and demonstrates excellent cyclic stability over 2500 repeated cycles with capacitance retention of >92%, achieving 94% coulombic efficiency. The good cycling stability is attributed to the inherent metallic electrical conductivity of SrFeO3-δ and the fortuitous tendency of the robust cation framework structure to accommodate flexible oxygen content. The surface capacitive and diffusion-controlled contributions for capacitance are about ∼30% and ∼70%, respectively, at peak current and a scan rate equivalent to 1 mV s-1. The higher capacitance and stable performance make SrFeO3-δ an economical and abundant pseudocapacitive electrode.

14.
Phys Chem Chem Phys ; 25(1): 326-340, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36477306

RESUMO

Grid-scale bulk energy storage solutions are needed to utilize the full potential of renewable energy technologies. Pseudocapacitive electrochemical energy storage can play a vital role in developing efficient energy storage solutions. The use of perovskites as anion intercalation-type pseudocapacitor electrodes has received significant attention in recent years. In this study, Sr-doped YMnO3i.e. Y1-xSrxMnO3-δ perovskite was prepared by the solid-state ceramic route and studied for electrochemical pseudocapacitance in aqueous KOH electrolyte. Microstructures, morphologies, and electrochemical properties of these materials were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance method. The formation of the mostly cubic phase, with 50% strontium doped YMnO3 (YSMO-50) provides an equivalent three-dimensional network and superior conductivity due to Mn3+-O2--Mn4+ hopping conduction. YSMO-50 exhibited low intrinsic resistance, 1.45 Ω cm-2, and the highest specific capacity, 259.83 F g-1 at a current density of 1 A g-1 in 2 M KOH aqueous electrolyte. Redox-mediated interconversion of oxide to hydroxide (M2+O2- + H2O + e- ↔ M+OH- + OH-) in aqueous media is shown to be the reason behind the high capacitance of YSMO-50. The excellent electrochemical performance of YSMOs was attributed to the reversible interconversion of oxide-ion into hydroxide ion coupled with surface redox reaction of Mn2+/Mn3+ and Mn3+/Mn4+ occurring during the charge-discharge process. The maximum energy density of 65.13 W h kg-1 was achieved at a power density of 0.45 kW kg-1 for an asymmetric mode, in which YSMO serves as a negative electrode and Activated carbon (AC) as a positive electrode in the PVA-KOH gel electrolyte. Our study reveals that the doping of low valence atom (Sr) at the A-site in perovskite manganites (YMnO3) may be an effective tool to enhance the pseudocapacitive performance of perovskite-based electrodes.

15.
Alzheimers Dement ; 18(6): 1141-1154, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34494715

RESUMO

INTRODUCTION: This study involved a parallel comparison of the diagnostic and longitudinal monitoring potential of plasma glial fibrillary acidic protein (GFAP), total tau (t-tau), phosphorylated tau (p-tau181 and p-tau231), and neurofilament light (NFL) in preclinical Alzheimer's disease (AD). METHODS: Plasma proteins were measured using Simoa assays in cognitively unimpaired older adults (CU), with either absence (Aß-) or presence (Aß+) of brain amyloidosis. RESULTS: Plasma GFAP, t-tau, p-tau181, and p-tau231 concentrations were higher in Aß+ CU compared with Aß- CU cross-sectionally. GFAP had the highest effect size and area under the curve (AUC) in differentiating between Aß+ and Aß- CU; however, no statistically significant differences were observed between the AUCs of GFAP, p-tau181, and p-tau231, but all were significantly higher than the AUC of NFL, and the AUC of GFAP was higher than the AUC of t-tau. The combination of a base model (BM), comprising the AD risk factors, age, sex, and apolipoprotein E gene (APOE) ε4 status with GFAP was observed to have a higher AUC (>90%) compared with the combination of BM with any of the other proteins investigated in the current study. Longitudinal analyses showed increased GFAP and p-tau181 in Aß+ CU and increased NFL in Aß- CU, over a 12-month duration. GFAP, p-tau181, p-tau231, and NFL showed significant correlations with cognition, whereas no significant correlations were observed with hippocampal volume. DISCUSSION: These findings highlight the diagnostic and longitudinal monitoring potential of GFAP and p-tau for preclinical AD.


Assuntos
Doença de Alzheimer , Amiloidose , Idoso , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides , Biomarcadores , Humanos , Prognóstico , Proteínas tau
16.
Int J Mol Sci ; 23(6)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35328459

RESUMO

Therapeutic antibodies used to treat cancer are effective in patients with advanced-stage disease. For example, antibodies that activate T-lymphocytes improve survival in many cancer subtypes. In addition, antibody-drug conjugates effectively target cytotoxic agents that are specific to cancer. This review discusses radiation-inducible antigens, which are stress-regulated proteins that are over-expressed in cancer. These inducible cell surface proteins become accessible to antibody binding during the cellular response to genotoxic stress. The lead antigens are induced in all histologic subtypes and nearly all advanced-stage cancers, but show little to no expression in normal tissues. Inducible antigens are exploited by using therapeutic antibodies that bind specifically to these stress-regulated proteins. Antibodies that bind to the inducible antigens GRP78 and TIP1 enhance the efficacy of radiotherapy in preclinical cancer models. The conjugation of cytotoxic drugs to the antibodies further improves cancer response. This review focuses on the use of radiotherapy to control the cancer-specific binding of therapeutic antibodies and antibody-drug conjugates.


Assuntos
Antineoplásicos , Imunoconjugados , Neoplasias , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/radioterapia
17.
Can J Urol ; 28(5): 10874-10877, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34657662

RESUMO

3D printing has been growing in many surgical fields including Urology. The primary use has been to print kidneys with tumors to better understand anatomy and to assist with surgical planning and education. Previous studies that utilized 3D printing of kidneys for partial nephrectomies have been limited by the cost and complexity of model creation, rendering them highly impractical to be used on a routine basis. Using a simpler and more cost-effective design and materials allow the 3D kidney models to be used in a wider range and number of patients. We describe our streamlined process to create 3D kidney models costing $30 on average and we believe this process can be repeated by others.


Assuntos
Neoplasias Renais , Modelos Anatômicos , Análise Custo-Benefício , Humanos , Neoplasias Renais/cirurgia , Nefrectomia , Impressão Tridimensional
18.
Drug Dev Res ; 82(8): 1144-1153, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33792939

RESUMO

In this study, the modulation of amounts sulfathiazolium cations in different 2,6-pyridinedicarboxylates is demonstrated. An uncommon monoionic sulfathiazolium zinc 2,6-pyridinedicarboxylate (1:1 electrolyte) complex was characterized. Conventional sulfathiazolium zinc-bis-2,6-pyridinedicarboxylate dianionic complexes (2:1 electrolyte) were formed when hydroxyaromatic compounds such as 1,3-dihydroxybenzene or 3-nitrophenol were used as guest components. Thus, with the aid of the hydroxyaromatic molecules the zinc-bis-2,6-pyridinedicarboxylate complexes were stabilized with the relatively large sized sulfathiazolium cations. It was a consequence of domain expansion by the phenolic compounds. Sandwiched aromatic guests between the 2,6-pyridinedicarboxylates provided appropriate packing to accommodate the two large cations in the self-assemblies, which helped to modulate the amounts of sulfathiazole in different formulations. Antibacterial activities with E. coli DH5α have shown that the salt and the complexes have lower g/ml antibacterial activity than the parent drug.


Assuntos
Antibacterianos/síntese química , Sulfatiazol/química , Antibacterianos/farmacologia , Cristalização , Ácidos Dicarboxílicos/química , Piridinas/química
19.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805778

RESUMO

Plasma amyloid-beta (Aß) has long been investigated as a blood biomarker candidate for Cerebral Amyloid Angiopathy (CAA), however previous findings have been inconsistent which could be attributed to the use of less sensitive assays. This study investigates plasma Aß alterations between pre-symptomatic Dutch-type hereditary CAA (D-CAA) mutation-carriers (MC) and non-carriers (NC) using two Aß measurement platforms. Seventeen pre-symptomatic members of a D-CAA pedigree were assembled and followed up 3-4 years later (NC = 8; MC = 9). Plasma Aß1-40 and Aß1-42 were cross-sectionally and longitudinally analysed at baseline (T1) and follow-up (T2) and were found to be lower in MCs compared to NCs, cross-sectionally after adjusting for covariates, at both T1(Aß1-40: p = 0.001; Aß1-42: p = 0.0004) and T2 (Aß1-40: p = 0.001; Aß1-42: p = 0.016) employing the Single Molecule Array (Simoa) platform, however no significant differences were observed using the xMAP platform. Further, pairwise longitudinal analyses of plasma Aß1-40 revealed decreased levels in MCs using data from the Simoa platform (p = 0.041) and pairwise longitudinal analyses of plasma Aß1-42 revealed decreased levels in MCs using data from the xMAP platform (p = 0.041). Findings from the Simoa platform suggest that plasma Aß may add value to a panel of biomarkers for the diagnosis of pre-symptomatic CAA, however, further validation studies in larger sample sets are required.


Assuntos
Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Angiopatia Amiloide Cerebral Familiar/genética , Fragmentos de Peptídeos/genética , Adulto , Peptídeos beta-Amiloides/sangue , Precursor de Proteína beta-Amiloide/sangue , Doenças Assintomáticas , Biomarcadores/sangue , Angiopatia Amiloide Cerebral Familiar/sangue , Angiopatia Amiloide Cerebral Familiar/diagnóstico , Angiopatia Amiloide Cerebral Familiar/patologia , Progressão da Doença , Feminino , Expressão Gênica , Genes Dominantes , Heterozigoto , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Mutação , Testes Neuropsicológicos , Linhagem , Fragmentos de Peptídeos/sangue
20.
J Med Ultrasound ; 29(1): 39-45, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34084715

RESUMO

BACKGROUND: The objective was to compare ultrasonographic findings with clinical and radiographic findings in osteoarthritis (OA)-affected knee joints. METHODS: This prospective study was conducted in Subharti Medical College, Meerut, after getting clearance from the ethical committee. Eighty-five symptomatic knees fulfilling American College of Rheumatology criteria for OA were included in the study. Patients with trauma, inflammatory, and infective conditions of the knee and with a history of intra-articular interventions and surgery were excluded. Demographic data, body mass index (BMI), visual analog scale (VAS), and Western Ontario and McMaster Universities Arthritis (WOMAC) questionnaire score were obtained. Kellgren-Lawrence (K-L) score was obtained on radiography. Ultrasonographic findings which were recorded include effusion, meniscal extrusion, femorotrochlear cartilage grading, maximum length of osteophytes at medial and lateral compartments, and presence or absence of Baker cyst. RESULTS: A total of 85 consecutive symptomatic knees were examined. The male: female ratio was 22:63, with a mean age of 54.52 ± 9.44 years, mean duration of disease of 24.24 ± 19.14 months, mean BMI of 28.91 ± 3.69 kg/m2, and mean score of VAS and WOMAC pain scale of 6.27 ± 1.45 and 62.45 ± 10.96, respectively. K-L grading of 1, 2, 3, and 4 was reported in 12.9%, 21.2%, 25.9%, and 40% of the knees, respectively. The mean VAS score and WOMAC score showed statistically significant correlation with KL grading (P < 0.05). Knees with the presence of osteophytes, medial meniscal extrusion, effusion, and medial femoral trochlear cartilage grading showed statistically significant correlation with VAS and WOMAC scores (P < 0.05). However, the correlation was not significant for lateral meniscus extrusion and lateral femoral trochlear cartilage grading. CONCLUSION: Our study found that K-L grading and few ultrasonographic criteria showed a significant positive correlation with pain scores, while few other ultrasonographic criteria did not. Both imaging modalities are complementary to each other, rather than one being superior to the other.

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