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1.
Nat Methods ; 21(3): 406-410, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38253843

RESUMEN

The discovery of the bioluminescence pathway in the fungus Neonothopanus nambi enabled engineering of eukaryotes with self-sustained luminescence. However, the brightness of luminescence in heterologous hosts was limited by performance of the native fungal enzymes. Here we report optimized versions of the pathway that enhance bioluminescence by one to two orders of magnitude in plant, fungal and mammalian hosts, and enable longitudinal video-rate imaging.


Asunto(s)
Eucariontes , Luminiscencia , Animales , Mamíferos
2.
World J Crit Care Med ; 12(3): 176-187, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37397590

RESUMEN

BACKGROUND: The proficiency of nursing professionals in the infection prevention and control (IPC) practices is a core component of the strategy to mitigate the challenge of healthcare associated infections. AIM: To test knowledge of nurses working in intensive care units (ICU) in South Asia and Middle East countries on IPC practices. METHODS: An online self-assessment questionnaire based on various aspects of IPC practices was conducted among nurses over three weeks. RESULTS: A total of 1333 nurses from 13 countries completed the survey. The average score was 72.8% and 36% of nurses were proficient (mean score > 80%). 43% and 68.3% of respondents were from government and teaching hospitals, respectively. 79.2% of respondents worked in < 25 bedded ICUs and 46.5% in closed ICUs. Statistically, a significant association was found between the knowledge and expertise of nurses, the country's per-capita income, type of hospitals, accreditation and teaching status of hospitals and type of ICUs. Working in high- and upper-middle-income countries (ß = 4.89, 95%CI: 3.55 to 6.22) was positively associated, and the teaching status of the hospital (ß = -4.58, 95%CI: -6.81 to -2.36) was negatively associated with the knowledge score among respondents. CONCLUSION: There is considerable variation in knowledge among nurses working in ICU. Factors like income status of countries, public vs private and teaching status of hospitals and experience are independently associated with nurses' knowledge of IPC practices.

3.
Chemosphere ; 314: 137713, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36596329

RESUMEN

Biofortification is a revolutionary technique for improving plant nutrition and alleviating human micronutrient deficiency. Fertilizers can help increase crop yield and growth, but applying too much fertilizer can be a problem because it leads to the release of greenhouse gases and eutrophication. One of the major global hazards that affects more than two million people globally is the decreased availability of micronutrients in food crops, which results in micronutrient deficiencies or "hidden hunger" in people. Micronutrients, like macronutrients, perform a variety of roles in plant and human nutrition. This review has highlighted the importance of micronutrients as well as their advantages. The uneven distribution of micronutrients in geological areas is not the only factor responsible for micronutrient deficiencies, other parameters including soil moisture, temperature, texture of the soil, and soil pH significantly affects the micronutrient concentration and their availability in the soil. To overcome this, different biofortification approaches are assessed in the review in which microbes mediated, Agronomic approaches, Plant breeding, and transgenic approaches are discussed. Hidden hunger can result in risky health conditions and diseases such as cancer, cardiovascular disease, osteoporosis, neurological disorders, and many more. Microbes-mediated biofortification is a novel and promising solution for the bioavailability of nutrients to plants in order to address these problems. Biofortification is cost effective, feasible, and environmentally sustainable. Bio-fortified crops boost our immunity, which helps us to combat these deadly viruses. The studies we discussed in this review have demonstrated that they can aid in the alleviation of hidden hunger.


Asunto(s)
Biofortificación , Salud Global , Humanos , Biofortificación/métodos , Fitomejoramiento , Micronutrientes , Suelo , Productos Agrícolas
4.
ACS Chem Biol ; 17(8): 2179-2187, 2022 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-35862857

RESUMEN

Sensitive and selective detection assays are essential for the accurate measurement of analytes in both clinical and research laboratories. Immunoassays that rely on nonoverlapping antibodies directed against the same target analyte (e.g., sandwich enzyme-linked immunosorbent assays (ELISAs)) are commonly used molecular detection technologies. Use of split enzyme reporters has simplified the workflow for these traditionally complex assays. However, identifying functional antibody pairs for a given target analyte can be cumbersome, as it generally involves generating and screening panels of antibodies conjugated to reporters. Accordingly, we sought a faster and easier reporter conjugation strategy to streamline antibody screening. We describe here the development of such a method that is based on an optimized ternary NanoLuc luciferase. This bioluminescence complementation system is comprised of a reagent-based thermally stable polypeptide (LgTrip) and two small peptide tags (ß9 and ß10) with lysine-reactive handles for direct conjugation onto antibodies. These reagents enable fast, single-step, wash-free antibody labeling and sensitive functional screening. Simplicity, speed, and utility of the one-pot labeling technology are demonstrated in screening antibody pairs for the analyte interleukin-4. The screen resulted in the rapid development of a sensitive homogeneous immunoassay for this clinically relevant cytokine.


Asunto(s)
Anticuerpos , Péptidos , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoensayo/métodos , Indicadores y Reactivos , Luciferasas
5.
Int J Mol Sci ; 23(4)2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35216317

RESUMEN

Despite the effectiveness of doxorubicin (DOXO) as a chemotherapeutic agent, dose-dependent development of chronic cardiotoxicity limits its application. The angiotensin-II receptor blocker losartan is commonly used to treat cardiac remodeling of various etiologies. The beta-3 adrenergic receptor agonist mirabegron was reported to improve chronic heart failure. Here we investigated the effects of losartan, mirabegron and their combination on the development of DOXO-induced chronic cardiotoxicity. Male Wistar rats were divided into five groups: (i) control; (ii) DOXO-only; (iii) losartan-treated DOXO; (iv) mirabegron-treated DOXO; (v) losartan plus mirabegron-treated DOXO groups. The treatments started 5 weeks after DOXO administration. At week 8, echocardiography was performed. At week 9, left ventricles were prepared for histology, qRT-PCR, and Western blot measurements. Losartan improved diastolic but not systolic dysfunction and ameliorated SERCA2a repression in our DOXO-induced cardiotoxicity model. The DOXO-induced overexpression of Il1 and Il6 was markedly decreased by losartan and mirabegron. Mirabegron and the combination treatment improved systolic and diastolic dysfunction and significantly decreased overexpression of Smad2 and Smad3 in our DOXO-induced cardiotoxicity model. Only mirabegron reduced DOXO-induced cardiac fibrosis significantly. Mirabegron and its combination with losartan seem to be promising therapeutic tools against DOXO-induced chronic cardiotoxicity.


Asunto(s)
Cardiomiopatías , Cardiotoxicidad , Acetanilidas , Animales , Cardiomiopatías/inducido químicamente , Cardiotoxicidad/tratamiento farmacológico , Cardiotoxicidad/etiología , Doxorrubicina/efectos adversos , Losartán/efectos adversos , Masculino , Ratas , Ratas Wistar , Tiazoles
6.
Sci Rep ; 11(1): 17495, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34471171

RESUMEN

Uremic cardiomyopathy is characterized by diastolic dysfunction (DD), left ventricular hypertrophy (LVH), and fibrosis. Angiotensin-II plays a major role in the development of uremic cardiomyopathy via nitro-oxidative and inflammatory mechanisms. In heart failure, the beta-3 adrenergic receptor (ß3-AR) is up-regulated and coupled to endothelial nitric oxide synthase (eNOS)-mediated pathways, exerting antiremodeling effects. We aimed to compare the antiremodeling effects of the angiotensin-II receptor blocker losartan and the ß3-AR agonist mirabegron in uremic cardiomyopathy. Chronic kidney disease (CKD) was induced by 5/6th nephrectomy in male Wistar rats. Five weeks later, rats were randomized into four groups: (1) sham-operated, (2) CKD, (3) losartan-treated (10 mg/kg/day) CKD, and (4) mirabegron-treated (10 mg/kg/day) CKD groups. At week 13, echocardiographic, histologic, laboratory, qRT-PCR, and Western blot measurements proved the development of uremic cardiomyopathy with DD, LVH, fibrosis, inflammation, and reduced eNOS levels, which were significantly ameliorated by losartan. However, mirabegron showed a tendency to decrease DD and fibrosis; but eNOS expression remained reduced. In uremic cardiomyopathy, ß3-AR, sarcoplasmic reticulum ATPase (SERCA), and phospholamban levels did not change irrespective of treatments. Mirabegron reduced the angiotensin-II receptor 1 expression in uremic cardiomyopathy that might explain its mild antiremodeling effects despite the unchanged expression of the ß3-AR.


Asunto(s)
Acetanilidas/farmacología , Cardiomiopatías/tratamiento farmacológico , Losartán/farmacología , Óxido Nítrico Sintasa de Tipo III/metabolismo , Insuficiencia Renal Crónica/complicaciones , Tiazoles/farmacología , Uremia/tratamiento farmacológico , Agonistas de Receptores Adrenérgicos beta 3/farmacología , Animales , Antihipertensivos/farmacología , Cardiomiopatías/etiología , Cardiomiopatías/metabolismo , Cardiomiopatías/patología , Masculino , Nefrectomía/efectos adversos , Óxido Nítrico Sintasa de Tipo III/genética , Ratas , Ratas Wistar , Uremia/etiología , Uremia/metabolismo , Uremia/patología
7.
Anal Chem ; 93(12): 5177-5184, 2021 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-33730483

RESUMEN

Enzyme-linked immunosorbent assays (ELISAs) are used extensively for the detection and quantification of biomolecules in clinical diagnostics as well as in basic research. Although broadly used, the inherent complexities of ELISAs preclude their utility for straightforward point-of-need testing, where speed and simplicity are essential. With this in mind, we developed a bioluminescence-based immunoassay format that provides a sensitive and simple method for detecting biomolecules in clinical samples. We utilized a ternary, split-NanoLuc luciferase complementation reporter consisting of two small peptides (11mer, 13mer) and a 17 kDa polypeptide combined with a luminogenic substrate to create a complete, shelf-stable add-and-read assay detection reagent. Directed evolution was used to optimize reporter constituent sequences to impart chemical and thermal stability, as well as solubility, while formulation optimization was applied to stabilize an all-in-one reagent that can be reconstituted in aqueous buffers or sample matrices. The result of these efforts is a robust, first-generation bioluminescence-based homogenous immunoassay reporter platform where all assay components can be configured into a stable lyophilized cake, supporting homogeneous, rapid, and sensitive one-step biomolecule quantification in complex human samples. This technology represents a promising alternative immunoassay format with significant potential to bring critical diagnostic molecular detection testing closer to the point-of-need.


Asunto(s)
Pruebas Inmunológicas , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoensayo , Indicadores y Reactivos , Luciferasas/genética
8.
Clin Res Cardiol ; 110(4): 507-531, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33591377

RESUMEN

Cancer management has undergone significant improvements, which led to increased long-term survival rates among cancer patients. Radiotherapy (RT) has an important role in the treatment of thoracic tumors, including breast, lung, and esophageal cancer, or Hodgkin's lymphoma. RT aims to kill tumor cells; however, it may have deleterious side effects on the surrounding normal tissues. The syndrome of unwanted cardiovascular adverse effects of thoracic RT is termed radiation-induced heart disease (RIHD), and the risk of developing RIHD is a critical concern in current oncology practice. Premature ischemic heart disease, cardiomyopathy, heart failure, valve abnormalities, and electrical conduct defects are common forms of RIHD. The underlying mechanisms of RIHD are still not entirely clear, and specific therapeutic interventions are missing. In this review, we focus on the molecular pathomechanisms of acute and chronic RIHD and propose preventive measures and possible pharmacological strategies to minimize the burden of RIHD.


Asunto(s)
Benchmarking/métodos , Manejo de la Enfermedad , Cardiopatías/diagnóstico , Corazón/efectos de la radiación , Oncología Médica , Sistemas de Atención de Punto/organización & administración , Traumatismos por Radiación/diagnóstico , Cardiopatías/terapia , Humanos , Traumatismos por Radiación/terapia
9.
iScience ; 24(1): 101986, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33490896

RESUMEN

For in vivo multicolor bioluminescence applications, red and near-infrared signals are desirable over shorter wavelength signals because they are not as susceptible to light attenuation by blood and tissue. Herein, we describe the development of a new click beetle luciferase mutant, CBG2, with a red-shifted color emission. When paired with NH2-NpLH2 luciferin, CBG2 (λ = 660 nm) and CBR2 (λ = 730 nm) luciferases can be used for simultaneous dual-color bioluminescence imaging in deep tissue. Using a spectral unmixing algorithm tool it is possible to distinguish each spectral contribution. Ultimately, this enzyme pair can expand the near-infrared bioluminescent toolbox to enable rapid visualization of multiple biological processes in deep tissue using a single substrate.

10.
Urol Oncol ; 39(10): 729.e7-729.e16, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33353867

RESUMEN

INTRODUCTION: Targeted alpha-radiation therapy (TAT) with 225Ac-labeled prostate-specific membrane antigen (PSMA) ligands is a promising novel treatment option for metastatic castration-resistant prostate cancer (mCRPC) patients. However, limited data are available on efficacy, quality of life (QoL), and pretherapeutic biomarkers. The aim of this study was to evaluate the efficacy of 225Ac-PSMA TAT and impact on QoL in advanced mCRPC, and to explore predictive biomarkers on pretherapeutic metastatic tissue biopsies. METHODS: Observational cohort study including consecutive patients treated with 225Ac-PSMA TAT between February 2016 and July 2018. Primary endpoint was overall survival (OS). Furthermore, prostate-specific antigen (PSA) changes, radiological response, safety, QoL, and xerostomia were evaluated. Biopsies were analyzed with immunohistochemistry and next-generation sequencing. RESULTS: Thirteen patients were included. Median OS was 8.5 months for the total cohort and 12.6 months for PSMA radioligand therapy-naïve patients. PSA declines of ≥90% and ≥50% were observed in 46% and 69% of patients, respectively. Six patients were radiologically evaluable; 50% showed partial response. All patients showed >90% total tumor volume reduction on PET imaging. Patients experienced clinically relevant decrease of pain and QoL improvement in physical and role functioning domains. Xerostomia persisted during follow-up. Patients with high baseline immunohistochemical PSMA expression or DNA damage repair alterations tended to have longer OS. CONCLUSIONS: TAT with 225Ac-PSMA resulted in remarkable survival and biochemical responses in advanced mCRPC patients. Patients experienced clinically relevant QoL improvement, although xerostomia was found to be nontransient. Baseline immunohistochemical PSMA expression and DNA damage repair status are potential predictive biomarkers of response to 225Ac-PSMA TAT.


Asunto(s)
Actinio/uso terapéutico , Antígeno Prostático Específico/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Actinio/farmacología , Humanos , Masculino , Metástasis de la Neoplasia , Antígeno Prostático Específico/farmacología , Resultado del Tratamiento
11.
PLoS One ; 15(12): e0243747, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33315907

RESUMEN

Firefly luciferase-based ATP detection assays are frequently used as a sensitive, cost-efficient method for monitoring hygiene in many industrial settings. Solutions of detection reagent, containing a mixture of a substrate and luciferase enzyme that produces photons in the presence of ATP, are relatively unstable and maintain only a limited shelf life even under refrigerated conditions. It is therefore common for the individual performing a hygiene test to manually prepare fresh reagent at the time of monitoring. To simplify sample processing, a liquid detection reagent with improved thermal stability is needed. The engineered firefly luciferase, Ultra-Glo™, fulfills one aspect of this need and has been valuable for hygiene monitoring because of its high resistance to chemical and thermal inactivation. However, solutions containing both Ultra-Glo™ luciferase and its substrate luciferin gradually lose the ability to effectively detect ATP over time. We demonstrate here that dehydroluciferin, a prevalent oxidative breakdown product of luciferin, is a potent inhibitor of Ultra-Glo™ luciferase and that its formation in the detection reagent is responsible for the decreased ability to detect ATP. We subsequently found that dialkylation at the 5-position of luciferin (e.g., 5,5-dimethylluciferin) prevents degradation to dehydroluciferin and improves substrate thermostability in solution. However, since 5,5-dialkylluciferins are poorly utilized by Ultra-Glo™ luciferase as substrates, we used structural optimization of the luciferin dialkyl modification and protein engineering of Ultra-Glo™ to develop a luciferase/luciferin pair that shows improved total reagent stability in solution at ambient temperature. The results of our studies outline a novel luciferase/luciferin system that could serve as foundations for the next generation of bioluminescence ATP detection assays with desirable reagent stability.


Asunto(s)
Luciferina de Luciérnaga/química , Sustancias Luminiscentes/química , Mediciones Luminiscentes/métodos , Adenosina Trifosfato/química , Alquilación , Indicadores y Reactivos , Luciferasas de Luciérnaga/química , Especificidad por Sustrato , Temperatura
12.
J Food Sci Technol ; 57(6): 2251-2258, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32431351

RESUMEN

Blueberry fruits are known for their high vitamin C, essential dietary fibre, antioxidant activity and anthocyanin pigments. Different blueberry varieties have been introduced in India but no attempt has been made for their nutritional profiling. Nutritional profiling of varieties helps us to know the unique varietal characters, which serves as a guideline for recommendation of a valuable variety for fresh consumption and/or processing. Therefore, the present study was conducted in eight different blueberry varieties such as 'Misty', 'Sharp Blue', 'Biloxi', 'Jewel', 'Gulf Coast', 'Blue Crop', 'Star', 'Legacy'. The results of the study revealed that all tested varieties differed significantly in physical attributes (10-berry weight, fruit firmness, roundness index, moisture content) and biochemical and functional attributes (ascorbic acid, total anthocyanin, total phenolic content, antioxidant activity, total sugars, organic acids) and mineral content. Regression analysis and Principal Component Analysis showed that antioxidant potential of blueberries was mainly contributed by phenolics followed by anthocyanins and ascorbic acid content. However for taste perception, fructose among sugars and succinic acid among sugars were the most influencing factors (p ≤ 0.05). Total phenolics and anthocyanins content were responsible for overall difference in functional attributes among the varieties. The attributes such as high fruit firmness, sensorial score, and appropriate shape and weight make 'Misty', the best variety for marketability and fresh consumption among all tested varieties.

13.
Thorac Cancer ; 10(12): 2289-2299, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31668020

RESUMEN

BACKGROUND: Both hypoxia and oncogenic mutations rewire tumor metabolism. In this study, glucose and glutamine metabolism-related markers were examined in stage I - resectable stage IIIA non-small cell lung cancer (NSCLC). Furthermore, expression of metabolism-related markers was correlated with mutational status to examine mutations associated with rewired tumor metabolism. METHODS: Mutation analysis was performed for 97 tumors. Glucose and glutamine metabolism-related marker expression was measured by immunofluorescent staining (protein) and qPCR (mRNA) (n = 81). RESULTS: Glutamine metabolism-related markers were significantly higher in adeno- than squamous cell NSCLCs. Glucose transporter 1 (GLUT1) protein expression was higher in solid compared to lepidic adenocarcinomas (P < 0.01). In adenocarcinomas, mRNA expression of glutamine transporter SLC1A5 correlated with tumor size (r(p) = 0.41, P = 0.005). Furthermore, SLC1A5 protein expression was significantly higher in adenocarcinomas with worse pTNM stage (r(s) = 0.39, P = 0.009). EGFR-mutated tumors showed lower GLUT1 protein (P = 0.017), higher glutaminase 2 (GLS2) protein (P = 0.025) and higher GLS2 mRNA expression (P = 0.004), compared to EGFR wild-type tumors. GLS mRNA expression was higher in KRAS-mutated tumors (P = 0.019). TP53-mutated tumors showed higher GLUT1 expression (P = 0.009). CONCLUSIONS: NSCLC is a heterogeneous disease, with differences in mutational status and metabolism-related marker expression between adeno- and squamous cell NSCLCs, and also within adenocarcinoma subtypes. GLUT1 and SLC1A5 expression correlate with aggressive tumor behavior in adenocarcinomas but not in squamous cell NSCLCs. Therefore, these markers could steer treatment modification for subgroups of adenocarcinoma patients. TP53, EGFR and KRAS mutations are associated with expression of glucose and glutamine metabolism-related markers in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Glucosa/metabolismo , Glutamina/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Mutación , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/patología , Técnica del Anticuerpo Fluorescente , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Neoplasias Pulmonares/patología , Estadificación de Neoplasias
14.
Front Oncol ; 9: 598, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31380269

RESUMEN

Background: A deleterious, late-onset side effect of thoracic radiotherapy is the development of radiation-induced heart disease (RIHD). It covers a spectrum of cardiac pathology including also heart failure with preserved ejection fraction (HFpEF) characterized by left ventricular hypertrophy (LVH) and diastolic dysfunction. MicroRNA-212 (miR-212) is a crucial regulator of pathologic LVH via FOXO3-mediated pathways in pressure-overload-induced heart failure. We aimed to investigate whether miR-212 and its selected hypertrophy-associated targets play a role in the development of RIHD. Methods: RIHD was induced by selective heart irradiation (50 Gy) in a clinically relevant rat model. One, three, and nineteen weeks after selective heart irradiation, transthoracic echocardiography was performed to monitor cardiac morphology and function. Cardiomyocyte hypertrophy and fibrosis were assessed by histology at week 19. qRT-PCR was performed to measure the gene expression changes of miR-212 and forkhead box O3 (FOXO3) in all follow-up time points. The cardiac transcript level of other selected hypertrophy-associated targets of miR-212 including extracellular signal-regulated kinase 2 (ERK2), myocyte enhancer factor 2a (MEF2a), AMP-activated protein kinase, (AMPK), heat shock protein 40 (HSP40), sirtuin 1, (SIRT1), calcineurin A-alpha and phosphatase and tensin homolog (PTEN) were also measured at week 19. Cardiac expression of FOXO3 and phospho-FOXO3 were investigated at the protein level by Western blot at week 19. Results: In RIHD, diastolic dysfunction was present at every time point. Septal hypertrophy developed at week 3 and a marked LVH with interstitial fibrosis developed at week 19 in the irradiated hearts. In RIHD, cardiac miR-212 was overexpressed at week 3 and 19, and FOXO3 was repressed at the mRNA level only at week 19. In contrast, the total FOXO3 protein level failed to decrease in response to heart irradiation at week 19. Other selected hypertrophy-associated target genes failed to change at the mRNA level in RIHD at week 19. Conclusions: LVH in RIHD was associated with cardiac overexpression of miR-212. However, miR-212 seems to play a role in the development of LVH via FOXO3-independent mechanisms in RIHD. As a central regulator of pathologic remodeling, miR-212 might become a novel target for RIHD-induced LVH and heart failure.

15.
Anal Sci ; 35(11): 1255-1261, 2019 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-31378775

RESUMEN

This paper discusses about the improvement of electrochemical characteristics of graphite paste electrode chemically modified with chitosan through physical crosslinking of the biopolymer with sodium tripolyphosphate. Biopolymer characterizations were performed by scanning electron microscopy, Fourier transform infrared spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The electrochemical characterization of Pb with graphite paste electrode modified with chitosan crosslinked with sodium tripolyphosphate (GPE-CTS-TPP) showed that the process is quasireversible, controlled by adsorption and involves the transfer of two electrons. Additionally, the physical crosslinking process decreased the electrode resistance as well as improved the electron transfer rate. Once the GPE-CTS-TPP showed enhanced morphological and electrochemical characteristics, it was applied for Pb determination by square wave anodic stripping voltammetry. The method presented appropriate accuracy (recoveries from 95 to 108% and concordance with comparative method between 90 and 107%), high sensitivity (limit of detection and quantification of Pb were 0.73 and 2.44 µg L-1, respectively) and could be applied to analytical determinations.


Asunto(s)
Quitosano/análogos & derivados , Electroquímica/instrumentación , Plomo/análisis , Adsorción , Quitosano/química , Electrodos , Grafito/química , Plomo/química , Límite de Detección
16.
Sci Rep ; 9(1): 1302, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30718600

RESUMEN

Chronic kidney disease (CKD) is a public health problem that increases the risk of cardiovascular morbidity and mortality. Heart failure with preserved ejection fraction (HFpEF) characterized by left ventricular hypertrophy (LVH) and diastolic dysfunction is a common cardiovascular complication of CKD. MicroRNA-212 (miR-212) has been demonstrated previously to be a crucial regulator of pathologic LVH in pressure-overload-induced heart failure via regulating the forkhead box O3 (FOXO3)/calcineurin/nuclear factor of activated T-cells (NFAT) pathway. Here we aimed to investigate whether miR-212 and its hypertrophy-associated targets including FOXO3, extracellular signal-regulated kinase 2 (ERK2), and AMP-activated protein kinase (AMPK) play a role in the development of HFpEF in CKD. CKD was induced by 5/6 nephrectomy in male Wistar rats. Echocardiography and histology revealed LVH, fibrosis, preserved systolic function, and diastolic dysfunction in the CKD group as compared to sham-operated animals eight and/or nine weeks later. Left ventricular miR-212 was significantly overexpressed in CKD. However, expressions of FOXO3, AMPK, and ERK2 failed to change significantly at the mRNA or protein level. The protein kinase B (AKT)/FOXO3 and AKT/mammalian target of rapamycin (mTOR) pathways are also proposed regulators of LVH induced by pressure-overload. Interestingly, phospho-AKT/total-AKT ratio was increased in CKD without significantly affecting phosphorylation of FOXO3 or mTOR. In summary, cardiac overexpression of miR-212 in CKD failed to affect its previously implicated hypertrophy-associated downstream targets. Thus, the molecular mechanism of the development of LVH in CKD seems to be independent of the FOXO3, ERK1/2, AMPK, and AKT/mTOR-mediated pathways indicating unique features in this form of LVH.


Asunto(s)
Expresión Génica , Hipertrofia Ventricular Izquierda/etiología , MicroARNs/genética , Insuficiencia Renal Crónica/complicaciones , Animales , Biopsia , Modelos Animales de Enfermedad , Ecocardiografía , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Perfilación de la Expresión Génica , Hipertrofia Ventricular Izquierda/diagnóstico , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Miocitos Cardíacos , Fosforilación , Ratas , Transducción de Señal
17.
Front Physiol ; 9: 1648, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30534079

RESUMEN

Chronic kidney disease (CKD) is a public health problem and a recognized risk factor for cardiovascular diseases (CVD). CKD could amplify the progression of chronic heart failure leading to the development of type 4 cardio-renal syndrome (T4CRS). The severity and persistence of heart failure are strongly associated with mortality risk in T4CRS. CKD is also a catabolic state leading to renal sarcopenia which is characterized by the loss of skeletal muscle strength and physical function. Renal sarcopenia also promotes the development of CVD and increases the mortality in CKD patients. In turn, heart failure developed in T4CRS could result in chronic muscle hypoperfusion and metabolic disturbances leading to or aggravating the renal sarcopenia. The interplay of multiple factors (e.g., comorbidities, over-activated renin-angiotensin-aldosterone system [RAAS], sympathetic nervous system [SNS], oxidative/nitrative stress, inflammation, etc.) may result in the progression of T4CRS and renal sarcopenia. Among these factors, oxidative/nitrative stress plays a crucial role in the complex pathomechanism and interrelationship between T4CRS and renal sarcopenia. In the heart and skeletal muscle, mitochondria, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, uncoupled nitric oxide synthase (NOS) and xanthine oxidase are major ROS sources producing superoxide anion (O2·-) and/or hydrogen peroxide (H2O2). O2·- reacts with nitric oxide (NO) forming peroxynitrite (ONOO-) which is a highly reactive nitrogen species (RNS). High levels of ROS/RNS cause lipid peroxidation, DNA damage, interacts with both DNA repair enzymes and transcription factors, leads to the oxidation/nitration of key proteins involved in contractility, calcium handling, metabolism, antioxidant defense mechanisms, etc. It also activates the inflammatory response, stress signals inducing cardiac hypertrophy, fibrosis, or cell death via different mechanisms (e.g., apoptosis, necrosis) and dysregulates autophagy. Therefore, the thorough understanding of the mechanisms which lead to perturbations in oxidative/nitrative metabolism and its relationship with pro-inflammatory, hypertrophic, fibrotic, cell death and other pathways would help to develop strategies to counteract systemic and tissue oxidative/nitrative stress in T4CRS and renal sarcopenia. In this review, we also focus on the effects of some well-known and novel pharmaceuticals, nutraceuticals, and physical exercise on cardiac and skeletal muscle oxidative/nitrative stress in T4CRS and renal sarcopenia.

18.
Nat Commun ; 9(1): 132, 2018 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-29317625

RESUMEN

The sensitivity of bioluminescence imaging in animals is primarily dependent on the amount of photons emitted by the luciferase enzyme at wavelengths greater than 620 nm where tissue penetration is high. This area of work has been dominated by firefly luciferase and its substrate, D-luciferin, due to the system's peak emission (~ 600 nm), high signal to noise ratio, and generally favorable biodistribution of D-luciferin in mice. Here we report on the development of a codon optimized mutant of click beetle red luciferase that produces substantially more light output than firefly luciferase when the two enzymes are compared in transplanted cells within the skin of black fur mice or in deep brain. The mutant enzyme utilizes two new naphthyl-luciferin substrates to produce near infrared emission (730 nm and 743 nm). The stable luminescence signal and near infrared emission enable unprecedented sensitivity and accuracy for performing deep tissue multispectral tomography in mice.


Asunto(s)
Benzotiazoles/metabolismo , Escarabajos/enzimología , Proteínas de Insectos/metabolismo , Luciferasas/metabolismo , Animales , Benzotiazoles/química , Células HEK293 , Humanos , Proteínas de Insectos/genética , Luciferasas/genética , Luminiscencia , Mediciones Luminiscentes/métodos , Células MCF-7 , Ratones Endogámicos C57BL , Ratones Desnudos , Microscopía Fluorescente , Mutación , Espectroscopía Infrarroja Corta
19.
Radiology ; 283(2): 547-559, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27846378

RESUMEN

Purpose To assess whether dynamic fluorine 18 (18F) fluorodeoxyglucose (FDG) positron emission tomography (PET) has added value over static 18F-FDG PET for tumor delineation in non-small cell lung cancer (NSCLC) radiation therapy planning by using pathology volumes as the reference standard and to compare pharmacokinetic rate constants of 18F-FDG metabolism, including regional variation, between NSCLC histologic subtypes. Materials and Methods The study was approved by the institutional review board. Patients gave written informed consent. In this prospective observational study, 1-hour dynamic 18F-FDG PET/computed tomographic examinations were performed in 35 patients (36 resectable NSCLCs) between 2009 and 2014. Static and parametric images of glucose metabolic rate were obtained to determine lesion volumes by using three delineation strategies. Pathology volume was calculated from three orthogonal dimensions (n = 32). Whole tumor and regional rate constants and blood volume fraction (VB) were computed by using compartment modeling. Results Pathology volumes were larger than PET volumes (median difference, 8.7-25.2 cm3; Wilcoxon signed rank test, P < .001). Static fuzzy locally adaptive Bayesian (FLAB) volumes corresponded best with pathology volumes (intraclass correlation coefficient, 0.72; P < .001). Bland-Altman analyses showed the highest precision and accuracy for static FLAB volumes. Glucose metabolic rate and 18F-FDG phosphorylation rate were higher in squamous cell carcinoma (SCC) than in adenocarcinoma (AC), whereas VB was lower (Mann-Whitney U test or t test, P = .003, P = .036, and P = .019, respectively). Glucose metabolic rate, 18F-FDG phosphorylation rate, and VB were less heterogeneous in AC than in SCC (Friedman analysis of variance). Conclusion Parametric images are not superior to static images for NSCLC delineation. FLAB-based segmentation on static 18F-FDG PET images is in best agreement with pathology volume and could be useful for NSCLC autocontouring. Differences in glycolytic rate and VB between SCC and AC are relevant for research in targeting agents and radiation therapy dose escalation. © RSNA, 2016 Online supplemental material is available for this article.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Fluorodesoxiglucosa F18/farmacocinética , Glucosa/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Imagen Molecular/métodos , Estadificación de Neoplasias , Tomografía de Emisión de Positrones/métodos , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
ACS Chem Biol ; 11(9): 2608-17, 2016 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-27414062

RESUMEN

The benefits provided by phenotypic screening of compound libraries are often countered by difficulties in identifying the underlying cellular targets. We recently described a new approach utilizing a chloroalkane capture tag, which can be chemically attached to bioactive compounds to facilitate the isolation of their respective targets for subsequent identification by mass spectrometry. The tag minimally affects compound potency and membrane permeability, enabling target engagement inside cells. Effective enrichment of these targets is achieved through selectivity in both their rapid capture onto immobilized HaloTag and their subsequent release by competitive elution. Here, we describe a significant improvement to this method where selective elution was achieved through palladium-catalyzed cleavage of an allyl-carbamate linkage incorporated into the chloroalkane capture tag. Selective tag cleavage provided robust release of captured targets exhibiting different modes of binding to the bioactive compound, including prolonged residence time and covalent interactions. Using the kinase inhibitors ibrutinib and BIRB796 as model compounds, we demonstrated the capability of this new method to identify both expected targets and "off-targets" exhibiting a range of binding affinities, cellular abundances, and binding characteristics.


Asunto(s)
Alcanos/química , Paladio/química , Proteínas/química , Catálisis
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