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1.
Mol Psychiatry ; 29(2): 387-401, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38177352

RESUMEN

Applications of machine learning in the biomedical sciences are growing rapidly. This growth has been spurred by diverse cross-institutional and interdisciplinary collaborations, public availability of large datasets, an increase in the accessibility of analytic routines, and the availability of powerful computing resources. With this increased access and exposure to machine learning comes a responsibility for education and a deeper understanding of its bases and bounds, borne equally by data scientists seeking to ply their analytic wares in medical research and by biomedical scientists seeking to harness such methods to glean knowledge from data. This article provides an accessible and critical review of machine learning for a biomedically informed audience, as well as its applications in psychiatry. The review covers definitions and expositions of commonly used machine learning methods, and historical trends of their use in psychiatry. We also provide a set of standards, namely Guidelines for REporting Machine Learning Investigations in Neuropsychiatry (GREMLIN), for designing and reporting studies that use machine learning as a primary data-analysis approach. Lastly, we propose the establishment of the Machine Learning in Psychiatry (MLPsych) Consortium, enumerate its objectives, and identify areas of opportunity for future applications of machine learning in biological psychiatry. This review serves as a cautiously optimistic primer on machine learning for those on the precipice as they prepare to dive into the field, either as methodological practitioners or well-informed consumers.


Asunto(s)
Psiquiatría Biológica , Aprendizaje Automático , Humanos , Psiquiatría Biológica/métodos , Psiquiatría/métodos , Investigación Biomédica/métodos
2.
Br J Cancer ; 130(11): 1855-1865, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38519707

RESUMEN

BACKGROUND: More than half of mesothelioma tumours show alterations in the tumour suppressor gene BAP1. BAP1-deficient mesothelioma is shown to be sensitive to EZH2 inhibition in preclinical settings but only showed modest efficacy in clinical trial. Adding a second inhibitor could potentially elevate EZH2i treatment efficacy while preventing acquired resistance at the same time. METHODS: A focused drug synergy screen consisting of 20 drugs was performed by combining EZH2 inhibition with a panel of anti-cancer compounds in mesothelioma cell lines. The compounds used are under preclinical investigation or already used in the clinic. The synergistic potential of the combinations was assessed by using the Bliss model. To validate our findings, in vivo xenograft experiments were performed. RESULTS: Combining EZH2i with ATMi was found to have synergistic potential against BAP1-deficient mesothelioma in our drug screen, which was validated in clonogenicity assays. Tumour growth inhibition potential was significantly increased in BAP1-deficient xenografts. In addition, we observe lower ATM levels upon depletion of BAP1 and hypothesise that this might be mediated by E2F1. CONCLUSIONS: We demonstrated the efficacy of the combination of ATM and EZH2 inhibition against BAP1-deficient mesothelioma in preclinical models, indicating the potential of this combination as a novel treatment modality using BAP1 as a biomarker.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada , Proteína Potenciadora del Homólogo Zeste 2 , Mesotelioma , Proteínas Supresoras de Tumor , Ubiquitina Tiolesterasa , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/deficiencia , Humanos , Proteína Potenciadora del Homólogo Zeste 2/antagonistas & inhibidores , Proteína Potenciadora del Homólogo Zeste 2/genética , Ubiquitina Tiolesterasa/antagonistas & inhibidores , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/deficiencia , Animales , Ratones , Mesotelioma/tratamiento farmacológico , Mesotelioma/patología , Mesotelioma/genética , Línea Celular Tumoral , Proteínas de la Ataxia Telangiectasia Mutada/antagonistas & inhibidores , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/deficiencia , Sinergismo Farmacológico , Femenino
3.
Small ; : e2307610, 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38342695

RESUMEN

Borophene, a 2D material exhibiting unique crystallographic phases like the anisotropic atomic lattices of ß12 and X3 phases, has attracted considerable attention due to its intriguing Dirac nature and metallic attributes. Despite surpassing graphene in electronic mobility, borophene's potential in energy storage and catalysis remains untapped due to its inherent electrochemical and catalytic limitations. Elemental doping emerges as a promising strategy to introduce charge carriers, enabling localized electrochemical and catalytic functionalities. However, effective doping of borophene has been a complex and underexplored challenge. Here, an innovative, one-pot microwave-assisted doping method, tailored for the ß12 phase of borophene is introduced. By subjecting dispersed ß12 borophene in dimethylformamide to controlled microwave exposure with sulfur powder and FeCl3 as doping precursors, S- and Fe doping in borophene can be controlled. Employing advanced techniques including high-resolution transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy, confirm successful sulfur and iron dopant incorporation onto ß12 borophene is confirmed, achieving doping levels of up to 11 % and 13 %, respectively. Remarkably, S- and Fe-doped borophene exhibit exceptional supercapacitive behavior, with specific capacitances of 202 and 120 F g-1 , respectively, at a moderate current density of 0.25 A g-1 .

4.
Nat Immunol ; 13(9): 888-99, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22797772

RESUMEN

Although much progress has been made in the understanding of the ontogeny and function of dendritic cells (DCs), the transcriptional regulation of the lineage commitment and functional specialization of DCs in vivo remains poorly understood. We made a comprehensive comparative analysis of CD8(+), CD103(+), CD11b(+) and plasmacytoid DC subsets, as well as macrophage DC precursors and common DC precursors, across the entire immune system. Here we characterized candidate transcriptional activators involved in the commitment of myeloid progenitor cells to the DC lineage and predicted regulators of DC functional diversity in tissues. We identified a molecular signature that distinguished tissue DCs from macrophages. We also identified a transcriptional program expressed specifically during the steady-state migration of tissue DCs to the draining lymph nodes that may control tolerance to self tissue antigens.


Asunto(s)
Diferenciación Celular/inmunología , Linaje de la Célula/inmunología , Células Dendríticas/inmunología , Transcripción Genética , Diferenciación Celular/genética , Células Dendríticas/citología , Perfilación de la Expresión Génica , Humanos
5.
Opt Lett ; 49(6): 1528-1531, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489442

RESUMEN

A numerical evaluation is conducted to assess the impact of distributing radio frequency (RF) signals through optical fiber links on the performance of a coherent multi-band multiple-input multiple-output (MIMO) radar system. The analysis focuses on scenarios where the antennas are widely separated in comparison to the employed signal wavelengths. The development of a model to quantify the phase noise (PN) induced on each RF band due to the signal transmission through optical fiber links between the centralized base station and each radar peripheral is described. Monte Carlo simulation results are collected to estimate the key performance indicators (KPIs) for varying standard single-mode fiber (SSMF) length and different PN contributions. The main contributors to the PN are revealed to be chromatic dispersion (CD), double Rayleigh scattering (DRS), and mechanical vibrations. In a shipborne scenario, a significant performance degradation occurs only when the length of the fiber links reaches approximately 20 km. Further, the PN impact has also been studied in a shipborne scenario to analyze the robustness of the system for worse phase noise level assumptions. The results reveal excellent robustness of the proposed centralized acquisition and processing approach in the presence of both very long fiber links and economically employed RF oscillators.

6.
Allergy ; 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38796780

RESUMEN

BACKGROUND: Allergic rhinitis is a common inflammatory condition of the nasal mucosa that imposes a considerable health burden. Air pollution has been observed to increase the risk of developing allergic rhinitis. We addressed the hypotheses that early life exposure to air toxics is associated with developing allergic rhinitis, and that these effects are mediated by DNA methylation and gene expression in the nasal mucosa. METHODS: In a case-control cohort of 505 participants, we geocoded participants' early life exposure to air toxics using data from the US Environmental Protection Agency, assessed physician diagnosis of allergic rhinitis by questionnaire, and collected nasal brushings for whole-genome DNA methylation and transcriptome profiling. We then performed a series of analyses including differential expression, Mendelian randomization, and causal mediation analyses to characterize relationships between early life air toxics, nasal DNA methylation, nasal gene expression, and allergic rhinitis. RESULTS: Among the 505 participants, 275 had allergic rhinitis. The mean age of the participants was 16.4 years (standard deviation = 9.5 years). Early life exposure to air toxics such as acrylic acid, phosphine, antimony compounds, and benzyl chloride was associated with developing allergic rhinitis. These air toxics exerted their effects by altering the nasal DNA methylation and nasal gene expression levels of genes involved in respiratory ciliary function, mast cell activation, pro-inflammatory TGF-ß1 signaling, and the regulation of myeloid immune cell function. CONCLUSIONS: Our results expand the range of air pollutants implicated in allergic rhinitis and shed light on their underlying biological mechanisms in nasal mucosa.

7.
Environ Res ; 252(Pt 2): 118969, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38642641

RESUMEN

Research laboratories generate a broad range of hazardous pharmacophoric chemical contaminants, from drugs to dyes used during various experimental procedures. In the recent past, biological methods have demonstrated great potential in the remediation of such contaminants. However, the presence of pharmacophoric chemicals containing antibiotics, xenobiotics, and heavy metals suppresses the growth and survivability of used microbial agents, thus decreasing the overall efficiency of biological remediation processes. Bacterial biofilm is a natural arrangement to counter some of these inhibitions but its use in a systemic manner, portable devices, and pollutant remediation plants post serious challenges. This could be countered by synthesizing a biodegradable carbon nanoparticle from bacterial biofilm. In this study, extracellular polymeric substance-based carbon nanoparticles (Bio-EPS-CNPs) were synthesized from bacterial biofilm derived from Bacillus subtilis NCIB 3610, as a model bacterial system. The produced Bio-EPS-CNPs were investigated for physiochemical properties by dynamic light scattering, optical, Fourier-transformed infrared, and Raman spectroscopy techniques, whereas X-ray diffraction study, scanning electron microscopy, and transmission electron microscopy were used to investigate structural and morphological features. The Bio-EPS-CNPs exhibited negative surface charge with spherical morphology having a uniform size of sub-100 nm. The maximum remediation of some laboratory-produced pharmacophoric chemicals was achieved through a five-round scavenging process and confirmed by UV/Vis spectroscopic analysis with respect to the used pharmacophore. This bioinspired remediation of used pharmacophoric chemicals was achieved through the mechanism of surface adsorption via hydrogen bonding and electrostatic interactions, as revealed by different characterizations. Further experiments were performed to investigate the effects of pH, temperature, stirring, and the protocol of scavenging to establish Bio-EPS-CNP as a possible alternative to be used in research laboratories for efficient removal of pharmacophoric chemicals by incorporating it in a portable, filter-based device.


Asunto(s)
Bacillus subtilis , Biopelículas , Carbono , Nanopartículas , Biopelículas/efectos de los fármacos , Carbono/química , Bacillus subtilis/efectos de los fármacos , Nanopartículas/química , Biodegradación Ambiental , Restauración y Remediación Ambiental/métodos
8.
Pancreatology ; 23(1): 9-17, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36509643

RESUMEN

BACKGROUND AND AIMS: The role of intestinal-barrier in acute pancreatitis(AP) is poorly understood. We aimed to assess structural and functional changes in the intestinal-barrier in patients with early AP (time from onset<2 weeks) and the effect of enteral nutrition on them. METHODS: In this prospective observational study, patients with early AP not on enteral nutrition were compared with controls for baseline intestinal-permeability(lactulose: mannitol ratio(L:M)), endotoxinemia(serum IgM/IgG anti-endotoxin antibodies), bacterial-translocation(serum bacterial 16S rRNA) and duodenal epithelial tight-junction structure by immunohistochemistry(IHC) for tight-junction proteins(claudin-2,-3,-4, zonula occludens-1(ZO1), junctional adhesion molecule(JAM) and occludin) and electron microscopy. These parameters were reassessed after 2 weeks enteral feeding in a AP patients subset. RESULTS: 96 patients with AP(age: 38.0 ± 14.5 years; etiology: biliary[46.8%]/alcohol[39.6%]; severe:53.2%, mortality:11.4%) and 40 matched controls were recruited. Patients with AP had higher baseline intestinal permeability(median L:M 0.176(IQR 0.073-0.376) vs 0.049(0.024-0.075) in controls; p < 0.001) and more frequent bacteraemia(positive bacterial 16S rRNA in 24/48 AP vs 0/21 controls; p < 0.001) with trend towards higher serum endotoxinemia(median IgG anti-endotoxin 78(51.2-171.6) GMU/ml vs 51.2(26.16-79.2) in controls; p = 0.061). Claudin-2, claudin-3, ZO1 were downregulated in both duodenal crypts and villi while claudin-4 and JAM were downregulated in duodenal villi and crypts respectively. 22 AP patients reassessed after initiation of enteral nutrition showed trend towards improving intestinal permeability, serum endotoxinemia and bacteraemia, with significant improvement in claudin-2,-3 in duodenal villi. CONCLUSION: Patients with AP have significant disturbances in intestinal barrier structure and function in first 2 weeks from onset that persist despite institution of enteral nutrition.


Asunto(s)
Bacteriemia , Pancreatitis , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , ARN Ribosómico 16S/genética , Claudina-2 , Enfermedad Aguda , Mucosa Intestinal , Inmunoglobulina G , Permeabilidad
9.
J Phys Chem A ; 127(44): 9206-9219, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37890168

RESUMEN

We have performed a coupled electron-nuclear dynamics study of H2+ molecular ions under the influence of an intense few-cycle 4.5 fs laser pulse with an intensity of 4 × 1014 W/cm2 and a central wavelength of 750 nm. Both quantum and classical dynamical methods are employed in the exact similar initial conditions with the aim of head-to-head comparison of two methodologies. A competition between ionization and dissociation channel is explained under the framework of quantum and classical dynamics. The origin of the electron localization phenomena is elucidated by observing the molecular and electronic wave packet evolution pattern. By probing with different carrier envelope phase (CEP) values of the ultrashort pulse, the possibility of electron localization on either of the two nuclei is investigated. The effects of initial vibrational states on final dissociation and ionization probabilities for several CEP values are studied in detail. Finally, asymmetries in the dissociation probabilities are calculated and mutually compared for both quantum and classical dynamical methodologies, whereas Franck-Condon averaging over the initial vibrational states is carried out in order to mimic the existing experimental conditions.

10.
J Basic Microbiol ; 63(7): 690-708, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36998101

RESUMEN

Medicinal plants are an important source of bioactive compounds and have been used to isolate various bioactive compounds having industrial applications. The demand for plants derived bioactive molecules is increasing gradually. However, the extensive use of these plants to extract bioactive molecules has threatened many plant species. Moreover, extracting bioactive molecules from these plants is laborious, costly, and time-consuming. So, some alternative sources and strategies are urgently needed to produce these bioactive molecules similar to that of plant origin. However, the interest in new bioactive molecules has recently shifted from plants to endophytic fungi because many fungi produce bioactive molecules similar to their host plant. Endophytic fungi live in mutualistic association within the healthy plant tissue without causing disease symptoms to the host plant. These fungi are a treasure house of novel bioactive molecules having broad pharmaceutical, industrial, and agricultural applications. The rapid increase in publications in this domain over the last three decades proves that natural product biologists and chemists are paying great attention to the natural bioactive products from endophytic fungi. Though endophytes are source of novel bioactive molecules but there is need of advanced technologies like clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9 (CRISPR-Cas9) and epigenetic modifiers to enhance the production of compounds having industrial applications. This review provides an overview of the various industrial applications of bioactive molecules produced by endophytic fungi and the rationale behind selecting specific plants for fungal endophyte isolation. Overall, this study presents the current state of knowledge and highlights the potential of endophytic fungi for developing alternative therapies for drug-resistant infections.


Asunto(s)
Antiinfecciosos , Productos Biológicos , Endófitos/metabolismo , Hongos/metabolismo , Plantas/microbiología , Simbiosis , Antiinfecciosos/metabolismo , Industria Farmacéutica , Productos Biológicos/metabolismo
11.
Monaldi Arch Chest Dis ; 94(1)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37522860

RESUMEN

Any type of contact with electricity of low or high voltage can cause injury to the human body, with a variable effect on the body. Low-voltage injury is quite common worldwide, but there is very little information present in the available literature. The degree of organ damage depends on many factors, which include the duration of electric current exposure, current type, and nature of the affected tissue. The most common presentations are muscle injury, hyperkalemia, pulmonary edema, and rarely isolated diffuse pulmonary hemorrhage. We present a case of bilateral pulmonary hemorrhage due to electric shock with no visible signs of damage to the chest wall when exposed to a 220 V shock. The diagnosis was confirmed by fresh hemoptysis, chest imaging that showed bilateral perihilar ground glass opacities, and bronchoscopy findings. Given a life-threatening condition, a timely diagnosis is required, as massive hemoptysis can occlude the airways, leading to hypoxia and mortality.


Asunto(s)
Enfermedades Pulmonares , Edema Pulmonar , Humanos , Hemoptisis/etiología , Hemoptisis/complicaciones , Hemorragia/diagnóstico por imagen , Hemorragia/etiología , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/etiología , Pulmón , Edema Pulmonar/diagnóstico por imagen , Edema Pulmonar/etiología
12.
Breast Cancer Res ; 24(1): 41, 2022 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-35715861

RESUMEN

BACKGROUND: The majority of BRCA1-mutant breast cancers are characterized by a triple-negative phenotype and a basal-like molecular subtype, associated with aggressive clinical behavior. Current treatment options are limited, highlighting the need for the development of novel targeted therapies for this tumor subtype. METHODS: Our group previously showed that EZH2 is functionally relevant in BRCA1-deficient breast tumors and blocking EZH2 enzymatic activity could be a potent treatment strategy. To validate the role of EZH2 as a therapeutic target and to identify new synergistic drug combinations, we performed a high-throughput drug combination screen in various cell lines derived from BRCA1-deficient and -proficient mouse mammary tumors. RESULTS: We identified the combined inhibition of EZH2 and the proximal DNA damage response kinase ATM as a novel synthetic lethality-based therapy for the treatment of BRCA1-deficient breast tumors. We show that the combined treatment with the EZH2 inhibitor GSK126 and the ATM inhibitor AZD1390 led to reduced colony formation, increased genotoxic stress, and apoptosis-mediated cell death in BRCA1-deficient mammary tumor cells in vitro. These findings were corroborated by in vivo experiments showing that simultaneous inhibition of EZH2 and ATM significantly increased anti-tumor activity in mice bearing BRCA1-deficient mammary tumors. CONCLUSION: Taken together, we identified a synthetic lethal interaction between EZH2 and ATM and propose this synergistic interaction as a novel molecular combination for the treatment of BRCA1-mutant breast cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Proteínas de la Ataxia Telangiectasia Mutada , Proteína BRCA1 , Neoplasias de la Mama , Proteína Potenciadora del Homólogo Zeste 2 , Indoles , Inhibidores de Proteínas Quinasas , Piridonas , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Proteínas de la Ataxia Telangiectasia Mutada/antagonistas & inhibidores , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteína BRCA1/deficiencia , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proteína Potenciadora del Homólogo Zeste 2/antagonistas & inhibidores , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Femenino , Humanos , Indoles/farmacología , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/patología , Ratones , Inhibidores de Proteínas Quinasas/farmacología , Piridonas/farmacología , Mutaciones Letales Sintéticas
13.
Phys Chem Chem Phys ; 24(39): 24582-24592, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36194188

RESUMEN

A coupled electron-nuclear dynamical study is performed to investigate the sub-cycle dissociation and ionization of the H2 molecule in a strong 750 nm 4.5 fs elliptically polarized laser pulse. A quasi-classical method is employed in which additional momentum-dependent potentials are added to the molecular Hamiltonian to account for the non-classical effects. The effect of molecular orientation with respect to the laser polarization plane on the probabilities of different dynamical channels and proton energy spectra has been examined. We demonstrate the 2D-control of proton anisotropy by manipulating the carrier-envelope phase of the pulse. We demonstrate that the quasi-classical method can capture the carrier-envelope phase effects in the dissociative ionization of the H2 molecule. Our results indicate that the classical models provide an efficient approach to study the mechanistic insights of strong-field molecular dynamics.

14.
Metabolomics ; 16(11): 117, 2020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-33085002

RESUMEN

INTRODUCTION: Despite the availability of several pre-processing software, poor peak integration remains a prevalent problem in untargeted metabolomics data generated using liquid chromatography high-resolution mass spectrometry (LC-MS). As a result, the output of these pre-processing software may retain incorrectly calculated metabolite abundances that can perpetuate in downstream analyses. OBJECTIVES: To address this problem, we propose a computational methodology that combines machine learning and peak quality metrics to filter out low quality peaks. METHODS: Specifically, we comprehensively and systematically compared the performance of 24 different classifiers generated by combining eight classification algorithms and three sets of peak quality metrics on the task of distinguishing reliably integrated peaks from poorly integrated ones. These classifiers were compared to using a residual standard deviation (RSD) cut-off in pooled quality-control (QC) samples, which aims to remove peaks with analytical error. RESULTS: The best performing classifier was found to be a combination of the AdaBoost algorithm and a set of 11 peak quality metrics previously explored in untargeted metabolomics and proteomics studies. As a complementary approach, applying our framework to peaks retained after filtering by 30% RSD across pooled QC samples was able to further distinguish poorly integrated peaks that were not removed from filtering alone. An R implementation of these classifiers and the overall computational approach is available as the MetaClean package at https://CRAN.R-project.org/package=MetaClean . CONCLUSION: Our work represents an important step forward in developing an automated tool for filtering out unreliable peak integrations in untargeted LC-MS metabolomics data.


Asunto(s)
Aprendizaje Automático , Metabolómica/métodos , Cromatografía Liquida , Espectrometría de Masas , Programas Informáticos
15.
J Phys Chem A ; 124(47): 9710-9720, 2020 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-33191740

RESUMEN

A theoretical study on the coupled electron-nuclear dynamics of HD+ molecular ions under ultrashort, intense laser pulses is performed by employing a well-established quasi-classical model. The influence of the laser carrier-envelope phase on various channel (H + D+, D + H+, and H+ + D+) probabilities is investigated at different laser field intensities. The carrier-envelope phase is found to govern the dissociation (H + D+ and D + H+) and Coulomb explosion (H+ + D+) channel probabilities. The kinetic energy release distributions of the fragments are also found to be sensitive to the carrier-envelope phase of the laser pulse. Our results are in agreement with the previously reported quantum dynamics studies and experiments.

16.
Hum Mutat ; 40(9): 1530-1545, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31301157

RESUMEN

Accurate prediction of the impact of genomic variation on phenotype is a major goal of computational biology and an important contributor to personalized medicine. Computational predictions can lead to a better understanding of the mechanisms underlying genetic diseases, including cancer, but their adoption requires thorough and unbiased assessment. Cystathionine-beta-synthase (CBS) is an enzyme that catalyzes the first step of the transsulfuration pathway, from homocysteine to cystathionine, and in which variations are associated with human hyperhomocysteinemia and homocystinuria. We have created a computational challenge under the CAGI framework to evaluate how well different methods can predict the phenotypic effect(s) of CBS single amino acid substitutions using a blinded experimental data set. CAGI participants were asked to predict yeast growth based on the identity of the mutations. The performance of the methods was evaluated using several metrics. The CBS challenge highlighted the difficulty of predicting the phenotype of an ex vivo system in a model organism when classification models were trained on human disease data. We also discuss the variations in difficulty of prediction for known benign and deleterious variants, as well as identify methodological and experimental constraints with lessons to be learned for future challenges.


Asunto(s)
Sustitución de Aminoácidos , Biología Computacional/métodos , Cistationina betasintasa/genética , Cistationina/metabolismo , Cistationina betasintasa/metabolismo , Homocisteína/metabolismo , Humanos , Fenotipo , Medicina de Precisión
17.
J Cell Biochem ; 120(6): 10688-10696, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30644120

RESUMEN

The contribution of proximal tubules (PT) to albumin uptake is now well recognized, however, its regulation is understudied area. There are reports suggesting that insulin resistance is associated with the development of albuminuria in nondiabetic individuals. We have previously reported reduced insulin receptor (IR) expression in renal-tubular-epithelial cells, including PT in various models of insulin resistance. However, the effect of a physiological fall in insulin levels and the role for IR in PT in tubular albumin uptake is not clear. To address these gaps in our understanding, we estimated urine excretion and renal uptake of albumin in fasted and fed C57Bl/6 mice injected with fluorescein isothiocyanate (FITC)-albumin (5 µg/mL/kg body weight, intraperitoneal, n = 6 per group). In addition, we compared spot urine analysis from 33 clinically healthy humans after overnight fasting (when insulin levels are lower than in the fed state) and then at 2 hours after 75 g oral glucose challenge (postprandial). Fasted mice had attenuated renal uptake of FITC-albumin and higher excretion in urine, relative to fed mice ( P = 0.04). Moreover, a significant drop in urine albumin-to-creatinine ratio (ACR) and urine albumin concentration (UAC) was observed in the postprandial state in these subjects ( P = 0.001 and P = 0.017, for ACR and UAC, respectively). The drop was negatively associated with postprandial blood glucose levels (ρ = -0.36, P = 0.03 for ΔUAC and ρ = -0.34, P = 0.05 for ΔACR). To test the role of IR in PT, we analyzed 24-hour urine albumin excretion in male mice with targeted deletion of IR from PT (insulin receptor knockout [IRKO]) and their wild-type (WT) littermates ( n = 7 per group). IRKO mice had significantly higher 24-hour urine albumin excretion relative to WT. Moreover, kidneys from KO mice revealed reduced expression of megalin and cubulin proteins in the PT relative to the WT. We also demonstrated insulin (100 nM) induced albumin internalization in human proximal tubule cells (hPT) and this effect of insulin was attenuated in hydroxy-2-naphthalenylmethylphosphonic acid (100 µM), a tyrosine kinase inhibitor, pretreated hPT. Our findings revealed albumin excretion was attenuated by glucose administration to fasting individuals implying a regulatory role for insulin in PT albumin reabsorption. Thus albuminuria associated with insulin resistance/diabetes may relate not only to glomerular dysfunction but also to impairment in insulin-mediated reabsorption.


Asunto(s)
Albuminuria/genética , Células Epiteliales/metabolismo , Insulina/metabolismo , Túbulos Renales Proximales/metabolismo , Receptor de Insulina/genética , Albuminuria/metabolismo , Albuminuria/fisiopatología , Animales , Creatinina/orina , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Ayuno/metabolismo , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Regulación de la Expresión Génica , Glucosa/metabolismo , Glucosa/farmacología , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/farmacología , Resistencia a la Insulina , Túbulos Renales Proximales/fisiopatología , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/genética , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Naftalenos/farmacología , Organofosfonatos/farmacología , Cultivo Primario de Células , Receptor de Insulina/deficiencia , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Albúmina Sérica/metabolismo
18.
J Environ Manage ; 206: 749-762, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29161677

RESUMEN

Pesticides are meant to control and destroy the pests and weeds. They are classified into different categories on the basis their origin and type of pest they target. Chemical pesticides such as insecticides, herbicides and fungicides are commonly used in agricultural fields. However, the excessive use of these agrochemicals have adverse effects on environment such as reduced population of insect pollinators, threat to endangered species and habitat of birds. Upon consumption; chemical pesticides also cause various health issues such as skin, eye and nervous system related problems and cancer upon prolonged exposure. Various techniques in the past have been developed on the basis of surface adsorption, membrane filtration and biological degradation to reduce the content of pesticides. However, slow response, less specificity and sensitivity are some of the drawbacks of such techniques. In recent times, Nanotechnology has emerged as a helping tool for the sensing and remediation of pesticides. This review focuses on the use of this technology for the detection, degradation and removal of pesticides. Nanomaterials have been classified into nanoparticles, nanotubes and nanocomposites that are commonly used for detection, degradation and removal of pesticides. The review also focuses on the chemistry behind the sensing and remediation of pesticides using nanomaterials. Different types of nanoparticles, viz. metal nanoparticles, bimetallic nanoparticles and metal oxide nanoparticles; nanotubes such as carbon nanotubes and halloysite nanotubes have been used for the detection, degradation and removal of pesticides. Further, various enzyme-based biosensors for detection of pesticides have also been summarized.


Asunto(s)
Nanotecnología , Plaguicidas/aislamiento & purificación , Animales , Herbicidas , Insecticidas , Nanotubos de Carbono , Plaguicidas/química
19.
J Cell Biochem ; 118(2): 276-285, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27322100

RESUMEN

Reduced insulin receptor protein levels have been reported in the kidney cortex from diabetic humans and animals. We recently reported that, targeted deletion of insulin receptor (IR) from proximal tubules (PT) resulted in hyperglycemia in non-obese mice. To elucidate the mechanism, we examined human proximal tubule cells (hPTC) and C57BL/6 mice fed with high-fat diet (HFD, 60% fat for 20 weeks). Immunoblotting revealed a significantly lower protein level of IR in HFD compare to normal chow diet (NCD). Furthermore, a blunted rise in p-AKT308 levels in the kidney cortex of HFD mice was observed in response to acute insulin (0.75 IU/kg body weight, i.p) relative to NCD n = 8/group, P < 0.05). Moreover, we found significantly higher transcript levels of phosphoenolpyruvate carboxykinase (PEPCK, a key gluconeogenic enzyme) in the kidney cortex from HFD, relative to mice on NCD. The higher level of PEPCK in HFD was confirmed by immunoblotting. However, no significant differences were observed in cortical glucose-6-phosphatase (G6Pase) or fructose-1,6, bisphosphosphatase (FBPase) enzyme transcript levels. Furthermore, we demonstrated insulin inhibited glucose production in hPTC treated with cyclic AMP and dexamethasone (cAMP/DEXA) to stimulate gluconeogenesis. Transcript levels of the gluconeogenic enzyme PEPCK were significantly increased in cAMP/DEXA-stimulated hPTC cells (n = 3, P < 0.05), and insulin attenuated this upregulation Furthermore, the effect of insulin on cAMP/DEXA-induced gluconeogenesis and PEPCK induction was significantly attenuated in IR (siRNA) silenced hPTC (n = 3, P < 0.05). Overall the above data indicate a direct role for IR expression as a determinant of PT-gluconeogenesis. Thus reduced insulin signaling of the proximal tubule may contribute to hyperglycemia in the metabolic syndrome via elevated gluconeogenesis. J. Cell. Biochem. 118: 276-285, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
AMP Cíclico/farmacología , Dexametasona/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Gluconeogénesis/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Receptor de Insulina/biosíntesis , Animales , Femenino , Humanos , Masculino , Síndrome Metabólico/metabolismo , Ratones
20.
Protein Expr Purif ; 136: 52-57, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26578115

RESUMEN

Plasmodium vivax is dependent on interaction with the Duffy antigen receptor for chemokines (DARC) for invasion of human erythrocytes. The P. vivax Duffy binding protein (PvDBP) mediates interaction of P. vivax merozoites with DARC. The DARC receptor-binding domain lies in a conserved N-terminal cysteine-rich region of PvDBP referred to as region II (PvDBPII). PvDBPII is an attractive vaccine candidate since antibodies raised against PvDBPII block erythrocyte invasion by P. vivax. Here, we describe methods to produce recombinant PvDBPII in its correctly folded conformation. A synthetic gene optimized for expression of PvDBPII in Escherichia coli and fed batch fermentation process based on exponential feeding strategy was used to achieve high levels of expression of recombinant PvDBPII. Recombinant PvDBPII was isolated from inclusion bodies, refolded by rapid dilution and purified by ion exchange chromatography. Purified recombinant PvDBPII was characterized for identity, purity and functional activity using standardized release assays. Recombinant PvDBPII formulated with various human compatible adjuvants including glycosylpyranosyl lipid A-stable emulsion (GLA-SE) and alhydrogel was used for immunogenicity studies in small animals to downselect a suitable formulation for clinical development. Sera collected from immunized animals were tested for recognition of PvDBPII and inhibition of PvDBPII-DARC binding. GLA-SE formulations of PvDBPII yielded higher ELISA and binding inhibition titres compared to PvDBPII formulated with alhydrogel. These data support further development of a recombinant vaccine for P. vivax based on PvDBPII formulated with GLA-SE.


Asunto(s)
Antígenos de Protozoos , Inmunogenicidad Vacunal , Vacunas contra la Malaria , Plasmodium vivax/genética , Proteínas Protozoarias , Receptores de Superficie Celular , Animales , Antígenos de Protozoos/biosíntesis , Antígenos de Protozoos/genética , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/aislamiento & purificación , Humanos , Vacunas contra la Malaria/biosíntesis , Vacunas contra la Malaria/genética , Vacunas contra la Malaria/inmunología , Vacunas contra la Malaria/aislamiento & purificación , Ratones , Ratones Endogámicos BALB C , Plasmodium vivax/inmunología , Dominios Proteicos , Proteínas Protozoarias/biosíntesis , Proteínas Protozoarias/genética , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/aislamiento & purificación , Receptores de Superficie Celular/biosíntesis , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/inmunología , Receptores de Superficie Celular/aislamiento & purificación , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación
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