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1.
Biochim Biophys Acta Proteins Proteom ; 1872(5): 141029, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38917877

RESUMEN

The Golgi apparatus is a critical organelle in protein sorting and lipid metabolism. Characterized by its stacked, flattened cisternal structure, the Golgi exhibits distinct polarity with its cis- and trans-faces orchestrating various protein maturation and transport processes. At the heart of its structural integrity and organisation are the Golgi Matrix Proteins (GMPs), predominantly comprising Golgins and GRASPs. These proteins contribute to this organelle's unique stacked and polarized structure and ensure the precise localization of Golgi-resident enzymes, which is crucial for accurate protein processing. Despite over a century of research since its discovery, the Golgi architecture's intricate mechanisms still need to be fully understood. Here, we discuss that GMPs across different Eukaryotic lineages present a significant tendency to form biomolecular condensates. Moreover, we validated experimentally that members of the GRASP family also exhibit a strong tendency. Our findings offer a new perspective on the possible roles of protein disorder and condensation of GMPs in the Golgi organisation.

2.
Protein Sci ; 33(7): e5085, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38923199

RESUMEN

Eukaryotic cells have developed intricate mechanisms for biomolecule transport, particularly in stressful conditions. This interdisciplinary study delves into unconventional protein secretion (UPS) pathways activated during starvation, facilitating the export of proteins bypassing most of the components of the classical secretory machinery. Specifically, we focus on the underexplored mechanisms of the GRASP's role in UPS, particularly in biogenesis and cargo recruitment for the vesicular-like compartment for UPS. Our results show that liquid-liquid phase separation (LLPS) plays a key role in the coacervation of Grh1, the GRASP yeast homologue, under starvation-like conditions. This association seems a precursor to the Compartment for Unconventional Protein Secretion (CUPS) biogenesis. Grh1's self-association is regulated by electrostatic, hydrophobic, and hydrogen-bonding interactions. Importantly, our study demonstrates that phase-separated states of Grh1 can recruit UPS cargo under starvation-like situations. Additionally, we explore how the coacervate liquid-to-solid transition could impact cells' ability to return to normal post-stress states. Our findings offer insights into intracellular protein dynamics and cell adaptive responses to stress.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Transporte de Proteínas , Separación de Fases
4.
Int J Biol Macromol ; 270(Pt 1): 132294, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38735602

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are molecules with two or more fused aromatic rings that occur naturally in the environment due to incomplete combustion of organic substances. However, the increased demand for fossil fuels in recent years has increased anthropogenic activity, contributing to the environmental concentration of PAHs. The enzyme chlorocatechol 1,2-dioxygenase from Pseudomonas putida (Pp 1,2-CCD) is responsible for the breakdown of the aromatic ring of catechol, making it a potential player in bioremediation strategies. Pp 1,2-CCD can tolerate a broader range of substrates, including halogenated compounds, than other dioxygenases. Here, we report the construction of a chimera protein able to form biomolecular condensates with potential application in bioremediation. The chimera protein was built by conjugating Pp 1,2-CCD to low complex domains (LCDs) derived from the DEAD-box protein Dhh1. We showed that the chimera could undergo liquid-liquid phase separation (LLPS), forming a protein-rich liquid droplet under different conditions (variable protein and PEG8000 concentrations and pH values), in which the protein maintained its structure and main biophysical properties. The condensates were active against 4-chlorocatechol, showing that the chimera droplets preserved the enzymatic activity of the native protein. Therefore, it constitutes a prototype of a microreactor with potential use in bioremediation.


Asunto(s)
Biodegradación Ambiental , Dioxigenasas , Hidrocarburos Policíclicos Aromáticos , Dioxigenasas/metabolismo , Dioxigenasas/química , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/metabolismo , Pseudomonas putida/enzimología , Catecoles/metabolismo , Catecoles/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo
5.
Transl Vis Sci Technol ; 13(5): 22, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38780953

RESUMEN

Purpose: To identify progression of nonproliferative diabetic retinopathy (NPDR) in patients with type 2 diabetes by combining optical coherence tomography angiography (OCTA) metrics and color fundus photography (CFP) images. Methods: This study was a post hoc analysis of a prospective longitudinal cohort study (CORDIS, NCT03696810) with 2-year duration. This study enrolled 122 eyes. Ophthalmological examinations included OCTA and CFP. OCTA metrics included skeletonized vessel density (SVD) and perfusion density (PD) at the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Microaneurysm turnover analysis and Early Treatment Diabetic Retinopathy Study (ETDRS) grading for diabetic retinopathy (DR) severity assessment were performed on 7-field CFP. Results: Eyes graded as ETDRS level 20 showed significant capillary nonperfusion predominantly in the inner ring area in the SCP (P < 0.001), whereas eyes graded as ETDRS level 35 and ETDRS levels 43 and 47 showed significant capillary nonperfusion in both the SCP and DCP in both inner and outer rings (P < 0.001). When evaluating rates of progression in capillary nonperfusion for the 2-year period of follow-up, changes were found predominantly in the DCP for SVD and PD and were better identified in the outer ring area. Microaneurysm turnover contributes to the characterization of NPDR progression by discriminating ETDRS level 35 from ETDRS levels 43 and 47 (P < 0.001), which could not be achieved using only OCTA metrics. Conclusions: Patterns of progression of NPDR can be identified combining OCTA examinations of the superficial and deep retinal capillary plexi of central retina and determination of microaneurysm turnover from fundus photographs. Translational Relevance: Our study reports results from a registered clinical trial that advances understanding of disease progression in NPDR.


Asunto(s)
Retinopatía Diabética , Progresión de la Enfermedad , Angiografía con Fluoresceína , Vasos Retinianos , Tomografía de Coherencia Óptica , Humanos , Retinopatía Diabética/diagnóstico por imagen , Retinopatía Diabética/patología , Masculino , Femenino , Persona de Mediana Edad , Tomografía de Coherencia Óptica/métodos , Estudios Prospectivos , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/patología , Anciano , Angiografía con Fluoresceína/métodos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/patología , Fotograbar
6.
Environ Sci Pollut Res Int ; 31(11): 16725-16734, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38326678

RESUMEN

Eisenia andrei is considered in OECD and ISO guidelines to be a suitable replacement for Eisenia fetida in ecotoxicological assays. This suggests that other alternative materials and methods could also be used in standard procedures for toxicity testing. The guidelines also favor using less time-consuming procedures and reducing costs and other limitations to ecotoxicological assessments. In recent years, spent coffee grounds (SCG) have been used to produce vermicompost and biochar and as an additive to organic fertilizers. In addition, the physicochemical characteristics of SCG indicate that the material is a suitable substrate for earthworms, with the organisms performing as well as in natural soil. In the present study, a battery of ecotoxicological tests was established with unwashed and washed SCG and a natural reference soil (LUFA 2.2). The test substrates were spiked with different concentrations of silver nitrate. Survival and reproduction of the earthworm E. andrei were assessed under different conditions, along with substrate basal respiration (SBR) as a proxy for microbial activity. Seedling emergence and the germination index of Lepidium sativum were also determined, following standard guidelines. Exposure to silver nitrate had similar effects on earthworm survival and reproduction, as the estimated effective concentrations (EC10 and EC50) in unwashed SCG and LUFA 2.2 overlapped. A hormetic effect was observed for SBR in LUFA 2.2 spiked with 12.8 mg/kg but not in unwashed SCG. Both SBR and root development were inhibited by similar concentrations of silver nitrate in washed SCG. The findings indicate that unwashed SCG could potentially be used as a substrate in E. andrei toxicity tests and support the eventual inclusion of this material in the standard guidelines.


Asunto(s)
Oligoquetos , Contaminantes del Suelo , Animales , Suelo/química , Café , Nitrato de Plata/farmacología , Contaminantes del Suelo/análisis , Ecotoxicología
7.
FEBS Lett ; 598(3): 363-376, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38253842

RESUMEN

Xylanases are of significant interest for biomass conversion technologies. Here, we investigated the allosteric regulation of xylan hydrolysis by the Bacillus subtilis GH11 endoxylanase. Molecular dynamics simulations (MDS) in the presence of xylobiose identified binding to the active site and two potential secondary binding sites (SBS) around surface residues Asn54 and Asn151. Arabinoxylan titration experiments with single cysteine mutants N54C and N151C labeled with the thiol-reactive fluorophore acrylodan or the ESR spin-label MTSSL validated the MDS results. Ligand binding at the SBS around Asn54 confirms previous reports, and analysis of the second SBS around N151C discovered in the present study includes residues Val98/Ala192/Ser155/His156. Understanding the regulation of xylanases contributes to efforts for industrial decarbonization and to establishing a sustainable energy matrix.


Asunto(s)
Bacillus subtilis , Simulación de Dinámica Molecular , Bacillus subtilis/genética , Sitios de Unión , Dominio Catalítico , Xilanos/metabolismo , Endo-1,4-beta Xilanasas/genética , Endo-1,4-beta Xilanasas/química , Endo-1,4-beta Xilanasas/metabolismo , Especificidad por Sustrato
8.
J Exp Bot ; 75(9): 2754-2771, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38224521

RESUMEN

l-Ascorbic acid (AsA, vitamin C) is a pivotal dietary nutrient with multifaceted importance in living organisms. In plants, the Smirnoff-Wheeler pathway is the primary route for AsA biosynthesis, and understanding the mechanistic details behind its component enzymes has implications for plant biology, nutritional science, and biotechnology. As part of an initiative to determine the structures of all six core enzymes of the pathway, the present study focuses on three of them in the model species Myrciaria dubia (camu-camu): GDP-d-mannose 3',5'-epimerase (GME), l-galactose dehydrogenase (l-GalDH), and l-galactono-1,4-lactone dehydrogenase (l-GalLDH). We provide insights into substrate and cofactor binding and the conformational changes they induce. The MdGME structure reveals a distorted substrate in the active site, pertinent to the catalytic mechanism. Mdl-GalDH shows that the way in which NAD+ association affects loop structure over the active site is not conserved when compared with its homologue in spinach. Finally, the structure of Mdl-GalLDH is described for the first time. This allows for the rationalization of previously identified residues which play important roles in the active site or in the formation of the covalent bond with FAD. In conclusion, this study enhances our understanding of AsA biosynthesis in plants, and the information provided should prove useful for biotechnological applications.


Asunto(s)
Ácido Ascórbico , Frutas , Myrtaceae , Proteínas de Plantas , Ácido Ascórbico/metabolismo , Ácido Ascórbico/biosíntesis , Frutas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/química , Myrtaceae/metabolismo , Myrtaceae/genética , Galactosa Deshidrogenasas/metabolismo , Galactosa Deshidrogenasas/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética
9.
Retina ; 44(4): 700-706, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38109709

RESUMEN

PURPOSE: To determine the degree of central microvascular closure using optical coherence tomography angiography in eyes of patients with type 2 diabetes with visible lesions only in the central retina or only in the periphery. METHODS: Cross-sectional study. All 127 eyes underwent ultra-widefield fundus photography 200° examinations with OPTOS California (Optos, Dunfermline, United Kingdom) and Cirrus Angioplex optical coherence tomography angiography 3 × 3 mm acquisitions (ZEISS, Dublin, CA). RESULTS: Twenty-five eyes showed visible lesions only in the central retina, 57 only in the peripheral retina, and 45 presented visible lesions in entire retina. The group with visible lesions only in the periphery showed definite closure in the superficial capillary plexus in 49% of the eyes, whereas the group with visible lesions only in the central seven-early treatment diabetic retinopathy study fields area showed a definite closure in 64%. CONCLUSION: Central capillary closure is already present in the initial stages of diabetic retinopathy even when lesions are only visible in the peripheral retina. Capillary closure in the superficial capillary plexus is three times more frequent than in the deep capillary plexus, demonstrating earlier closure of the superficial capillary plexus. Eyes with visible lesions only in the periphery show a milder form of retinopathy.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Humanos , Estudios Transversales , Vasos Retinianos/patología , Angiografía con Fluoresceína/métodos , Retina/patología , Tomografía de Coherencia Óptica/métodos
10.
Acta Ophthalmol ; 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798863

RESUMEN

INTRODUCTION: Diabetic retinopathy (DR) is both a microangiopathy and a neurodegenerative disease. However, the connections between both changes are not well known. PURPOSE: To characterise the longitudinal retinal ganglion cell layer + inner plexiform layer (GCL + IPL) changes and their association with microvascular changes in type-2 diabetes (T2D) patients with nonproliferative diabetic retinopathy (NPDR). METHODS: This two-year prospective study (CORDIS, NCT03696810) included 122 T2D individuals with NPDR identified as risk phenotypes B and C, which present a more rapid progression. Phenotype C was identified by decreased VD ≥ 2SD in healthy controls, and phenotype B, identified by subclinical macular oedema with only minimal vascular closure. The GCL + IPL thickness, vessel density, perfusion density and area of intercapillary spaces (AIS) were assessed by optical coherence tomography (OCT) and OCT angiography (OCTA). Linear mixed effects models were employed to evaluate the retinal GCL + IPL progression and its associations. RESULTS: Regarding GCL + IPL thickness, T2D individuals presented on average 80.1 ± 7.49 µm, statistically significantly lower than the healthy control group, 82.5 ± 5.71 (p = 0.022), with only phenotype C differing significantly from controls (p = 0.006). GCL + IPL thickness steadily decreased during the two-year period in both risk phenotypes, with an annual decline rate of -0.372 µm/year (p < 0.001). Indeed, phenotype C showed a higher rate of progression (-0.459 µm/year, p < 0.001) when compared to phenotype B (-0.296 µm/year, p = 0.036). Eyes with ETDRS grade 20 showed GCL + IPL thickness values comparable to those of healthy control group (83.3 ± 5.80 and 82.7 ± 5.50 µm, respectively, p = 0.880), whereas there was a progressive decrease in GCL + IPL thickness in ETDRS grades 35 and 43-47 associated with the increase in severity of the retinopathy (-0.276 µm/year, p = 0.004; -0.585 µm/year, p = 0.013, respectively). Furthermore, the study showed statistically significant associations between the progressive thinning of GCL + IPL and the progressive increase in retinal capillary non-perfusion, with particular relevance for AIS (p < 0.001). CONCLUSIONS: Our findings showed that, in eyes with NPDR and at risk for progression, retinal neurodegeneration occurs at different rates in different risk phenotypes, and it is associated with retinal microvascular non-perfusion.

11.
Ophthalmic Res ; 66(1): 1327-1334, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37820590

RESUMEN

INTRODUCTION: The aim of the study was to identify retinal microvascular changes using optical coherence tomography angiography (OCTA) in type 2 diabetes (T2D) patients with preclinical retinopathy identified by ultra-widefield fundus photography (UWF-FP). METHODS: This is a cross-sectional observational study. All patients underwent UWF-FP 200° examinations with OPTOS California (Optos, Dunfermline, UK) and Cirrus AngioPlex® spectral-domain (SD)-OCTA 3 × 3 mm acquisitions (ZEISS, Dublin, CA, USA). The absence of visible lesions was identified using UWF-FP. RESULTS: One hundred and ninety three eyes of individuals with T2D with no visible lesions in the fundus and identified in a screening setting were included in the study. Skeletonized vessel density (SVD), perfusion density (PD), and areas of capillary nonperfusion (CNP) values on SD-OCTA were significantly decreased when compared with healthy population (p < 0.001). SVD and CNP values of the superficial capillary plexus (SCP) were more frequently decreased (35% and 45%, respectively) than SVD values of the deep capillary plexus (DCP) (9% and 15%, respectively), demonstrating that diabetic microvascular changes occur earlier in the SCP than in the DCP. The ischemic phenotype, identified by a definite decrease in SVD or CNP in the SCP may, therefore, be identified in the preclinical stage of diabetic retinal disease. CONCLUSIONS: Retinal capillary nonperfusion detected by OCTA metrics of SVD and CNP can be identified in the central retina in eyes with T2D before development of visible lesions in the retina. Our findings confirm the relevance of OCTA to identify macular microvascular changes in the initial stages of diabetic retinopathy, allowing the identification of its ischemic phenotype very early in the disease process.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Humanos , Retinopatía Diabética/patología , Diabetes Mellitus Tipo 2/complicaciones , Vasos Retinianos/patología , Estudios Transversales , Angiografía con Fluoresceína/métodos , Retina , Isquemia/diagnóstico , Tomografía de Coherencia Óptica/métodos
12.
Ophthalmol Ther ; 12(1): 485-500, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36495395

RESUMEN

INTRODUCTION: Characterization of 2-year progression of different risk phenotypes in eyes with mild and moderate nonproliferative diabetic retinopathy (NPDR) in type 2 diabetes (T2D). METHODS: A 2-year prospective longitudinal cohort study (CORDIS, NCT03696810) was conducted. Ophthalmological examinations were performed including best corrected visual acuity, color fundus photography and optical coherence tomography (OCT and OCTA). OCT metrics, central retinal thickness and ganglion cell layer + inner plexiform layer (GCL + IPL) thickness were analyzed. OCTA metrics, vessel density (VD), perfusion density (PD) and area of intercapillary spaces (AIS) were obtained from superficial and deep capillary plexus (SCP, DCP). Only phenotype C identified by decreased VD ≥ 2 SD of healthy controls and phenotype B identified by subclinical macular edema with decreased VD < 2 SD of healthy controls were included. RESULTS: One hundred twenty-two eyes from T2D individuals were included in study; 65 eyes (53%) were classified as phenotype B and 57 eyes (47%) as phenotype C. For phenotype B, progression was associated with thinning of the GCL + IPL (ETDRS 35, 1 year p = 0.013, 2 year p < 0.001; ETDRS 43-47, 2 year p = 0.003) and vessel closure involving mainly the DCP for both ETDRS grades (ETDRS 35, 1 year p = 0.025, 2 year p = 0.034; ETDRS 43-47, 1 year p = 0.011). For phenotype C there was also progressive thinning of the GCL + IPL (ETDRS 35, in both years p ≤ 0.001; ETDRS 43-47, 1 year p = 0.002, 2 year p = 0.001), with vessel closure involving mainly SCP (ETDRS 35, 1 year p = 0.012, 2 year p = 0.023 in full-retina), which appeared to stabilize at maximal values in ETDRS grade 43-47 at the end of 2 years. ETDRS severity changes at the end of the 2-year period showed that worsening was associated with phenotype C with changes involving predominantly the SCP (VD, p = 0.005; PD, p = 0.008; AIS, p = 0.005). CONCLUSIONS: Association between ETDRS classification of NPDR severity and identification of different risk phenotypes offers new perspective to predict disease progression in T2D individuals with NPDR.

13.
São Paulo med. j ; 140(6): 837-845, Nov.-Dec. 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1410230

RESUMEN

ABSTRACT BACKGROUND: Artificial intelligence (AI) deals with development of algorithms that seek to perceive one's environment and perform actions that maximize one's chance of successfully reaching one's predetermined goals. OBJECTIVE: To provide an overview of the basic principles of AI and its main studies in the fields of glaucoma, retinopathy of prematurity, age-related macular degeneration and diabetic retinopathy. From this perspective, the limitations and potential challenges that have accompanied the implementation and development of this new technology within ophthalmology are presented. DESIGN AND SETTING: Narrative review developed by a research group at the Universidade Federal de São Paulo (UNIFESP), São Paulo (SP), Brazil. METHODS: We searched the literature on the main applications of AI within ophthalmology, using the keywords "artificial intelligence", "diabetic retinopathy", "macular degeneration age-related", "glaucoma" and "retinopathy of prematurity," covering the period from January 1, 2007, to May 3, 2021. We used the MEDLINE database (via PubMed) and the LILACS database (via Virtual Health Library) to identify relevant articles. RESULTS: We retrieved 457 references, of which 47 were considered eligible for intensive review and critical analysis. CONCLUSION: Use of technology, as embodied in AI algorithms, is a way of providing an increasingly accurate service and enhancing scientific research. This forms a source of complement and innovation in relation to the daily skills of ophthalmologists. Thus, AI adds technology to human expertise.

14.
Ophthalmic Res ; 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36170808

RESUMEN

INTRODUCTION: To characterize the two-year progression of risk phenotypes of nonproliferative diabetic retinopathy (NPDR) in type 2 diabetes (T2D) Phenotype C, or ischemic phenotype, identified by decreased skeletonized retinal vessel density (VD), ≥ 2 SD over normal values, and Phenotype B, or edema phenotype, identified by increased retinal thickness, i.e. subclinical macular edema, and no significant decrease in VD. METHODS: A prospective longitudinal cohort study (CORDIS, NCT03696810) was conducted with 4 visits (baseline, 6-months, one-year and two-year). Ophthalmological examinations included best corrected visual acuity, color fundus photography (CFP) and optical coherence tomography (OCT) and OCT Angiography. Early Treatment Diabetic Retinopathy Study grading was performed at the baseline and last visits based on 7-fields CFP. RESULTS: One hundred and twenty-two eyes from T2D individuals with NPDR fitted in the categories of phenotype B and C and completed the two-years follow-up. Sixty-five (53%) of the eyes were classified as phenotype B and 57 (47%) eyes as phenotype C. Neurodegeneration represented by thinning of the ganglion cell layer and inner plexiform layer was present in both phenotypes and showed significant progression over the two-year period (p<0.001). In phenotype C, significant progression in the two-year period was identified in decreased skeletonized VD (p=0.01), whereas in phenotype B microvascular changes involved preferentially decreases in perfusion density (PD, p=0.012). Phenotype B with changes in VD and PD (flow) and preferential involvement of the deep capillary plexus (p<0.001) is associated with development of center-involved macular edema. DISCUSSION: In the two-year period of follow-up both phenotypes B and C showed progression in retinal neurodegeneration, with changes at the microvascular level characterized by decreases in PD in phenotype B and decreases in VD in phenotype C.

15.
Sao Paulo Med J ; 140(6): 837-845, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36043665

RESUMEN

BACKGROUND: Artificial intelligence (AI) deals with development of algorithms that seek to perceive one's environment and perform actions that maximize one's chance of successfully reaching one's predetermined goals. OBJECTIVE: To provide an overview of the basic principles of AI and its main studies in the fields of glaucoma, retinopathy of prematurity, age-related macular degeneration and diabetic retinopathy. From this perspective, the limitations and potential challenges that have accompanied the implementation and development of this new technology within ophthalmology are presented. DESIGN AND SETTING: Narrative review developed by a research group at the Universidade Federal de São Paulo (UNIFESP), São Paulo (SP), Brazil. METHODS: We searched the literature on the main applications of AI within ophthalmology, using the keywords "artificial intelligence", "diabetic retinopathy", "macular degeneration age-related", "glaucoma" and "retinopathy of prematurity," covering the period from January 1, 2007, to May 3, 2021. We used the MEDLINE database (via PubMed) and the LILACS database (via Virtual Health Library) to identify relevant articles. RESULTS: We retrieved 457 references, of which 47 were considered eligible for intensive review and critical analysis. CONCLUSION: Use of technology, as embodied in AI algorithms, is a way of providing an increasingly accurate service and enhancing scientific research. This forms a source of complement and innovation in relation to the daily skills of ophthalmologists. Thus, AI adds technology to human expertise.


Asunto(s)
Retinopatía Diabética , Oftalmología , Retinopatía de la Prematuridad , Recién Nacido , Humanos , Brasil , Inteligencia Artificial , Inteligencia
16.
Metabolites ; 12(7)2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35888705

RESUMEN

Articaine (ATC) and lidocaine (LDC) are the local anesthetics (LAs) currently most employed in dentistry. Cases of paresthesia, reported more frequently for ATC, have raised concerns about their potential neurotoxicity, calling for further investigation of their biological effects in neuronal cells. In this work, the impact of ATC and LDC on the metabolism of SH-SY5Y cells was investigated through 1H NMR metabolomics. For each LA, in vitro cultured cells were exposed to concentrations causing 10 and 50% reductions in cell viability, and their metabolic intracellular and extracellular profiles were characterized. Most effects were common to ATC and LDC, although with varying magnitudes. The metabolic variations elicited by the two LAs suggested (i) downregulation of glycolysis and of glucose-dependent pathways (e.g., one-carbon metabolism and hexosamine biosynthetic pathway), (ii) disturbance of branched chain amino acids (BCAA) catabolism, (iii) downregulation of TCA cycle anaplerotic fueling and activation of alternative energy producing pathways, (iv) interference with choline metabolism and (v) lipid droplet build-up. Interestingly, LDC had a greater impact on membrane phospholipid turnover, as suggested by higher phosphatidylcholine to phosphocholine conversion. Moreover, LDC elicited an increase in triglycerides, whereas cholesteryl esters accumulated in ATC-exposed cells, suggesting a different composition and handling of lipid droplets.

17.
Toxics ; 10(7)2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35878307

RESUMEN

Emerging contaminants such as nanoplastics (NPs), as well as manufacturing by-products such as plasticizers, have gained global attention and concern due to their limited biodegradability and their potential impact on human health, in particular the effects on respiratory tissue. In parallel, in vitro cell culture techniques are key to the assessment and characterization of toxic effects and cellular mechanisms in different types of tissues and should provide relevant information to understand the hazardous potential of these emergent contaminants. This systematic review presents the main results on the current knowledge of the effects of NPs and plasticizers on lung cells, as assessed with the use of in vitro cell culture techniques. From the selected studies (n = 10), following the PRISMA approach, it was observed that cell viability was the most frequently assessed endpoint and that most studies focused on epithelial cells and exposures to polystyrene (PS). It was observed that exposure to NPs or plasticizers induces cytotoxicity in a dose-dependent manner, regardless of the size of the NPs. Furthermore, there is evidence that the characteristics of NPs can affect the toxic response by promoting the association with other organic compounds. As such, further in vitro studies focusing on the combination of NPs with plasticizers will be essential for the understanding of mechanisms of NPs toxicity.

18.
Sci Rep ; 12(1): 10601, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35732685

RESUMEN

Chikungunya virus (CHIKV) is the causative agent of Chikungunya fever, an acute febrile and arthritogenic illness with no effective treatments available. The development of effective therapeutic strategies could be significantly accelerated with detailed knowledge of the molecular components behind CHIKV replication. However, drug discovery is hindered by our incomplete understanding of their main components. The RNA-dependent RNA-polymerase (nsP4-CHIKV) is considered the key enzyme of the CHIKV replication complex and a suitable target for antiviral therapy. Herein, the nsP4-CHIKV was extensively characterized through experimental and computational biophysical methods. In the search for new molecules against CHIKV, a compound designated LabMol-309 was identified as a strong ligand of the nsp4-CHIKV and mapped to bind to its active site. The antiviral activity of LabMol-309 was evaluated in cellular-based assays using a CHIKV replicon system and a reporter virus. In conclusion, this study highlights the biophysical features of nsP4-CHIKV and identifies a new compound as a promising antiviral agent against CHIKV infection.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Antivirales/uso terapéutico , Virus Chikungunya/genética , Humanos , Ligandos , ARN/metabolismo , ARN Polimerasa Dependiente del ARN , Replicación Viral
19.
Einstein (Sao Paulo) ; 20: eAO6613, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35544891

RESUMEN

OBJECTIVE: To analyze the most common ophthalmologic disorders in pregnant women seen in a hospital in Munich in Germany using a big data analysis system, as well as to compare the results obtained with those from other epidemiological studies that used different data acquisition methods. METHODS: We retrospectively analyzed electronic health records of pregnant women who were seen at the ophthalmology department from 2003 to 2019 at the Ludwig-Maximilians-Universität München hospital. The main complaints that led to ophthalmic consultations during this period were evaluated, and also the variation in intraocular pressure of patients throughout gestational trimesters by analyzing data from the data warehouse system. RESULTS: A total of 27,326 electronic health records were analyzed. Of participants, 149 (0.54%) required eye care during pregnancy. Their mean intraocular pressure was 17mmHg in the first trimester, 12mmHg in the second trimester, and 14mmHg in the third trimester. The most prevalent findings were dry eye (29.3%) and conjunctivitis (16%), and ametropia (16%). The most common posterior segment problem was diabetic retinopathy (4.6%). The lower mean intraocular pressure in the second and third trimester found in our study is in accordance with other studies that used other method for data acquisition. CONCLUSION: The most common ophthalmic conditions found in this study population were dry eye, conjunctivitis, and ametropia. The use of data warehouse proved to be useful for acquiring and analyzing data from many patients. This study results are comparable with other studies in published literature that adopted different methodology.


Asunto(s)
Conjuntivitis , Síndromes de Ojo Seco , Errores de Refracción , Data Warehousing , Femenino , Alemania/epidemiología , Humanos , Embarazo , Estudios Retrospectivos
20.
J Biol Inorg Chem ; 27(4-5): 431-441, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35524804

RESUMEN

New compounds to fight cancer are needed due to cancer high incidence and lack of curative treatments for several classes of this disease. Metal-based coordination compounds offer a variety of molecules that can turn into drugs. Among them, coordination copper complexes are emerging as an attractive class of compounds for cancer treatment. A series of [Cu(L-dipeptide)(tmp)] (tmp = 3,4,7,8-tetramethyl-1,10-phenanthroline) complexes were synthesized and characterized in the solid state, including the determination of the crystalline structure of [Cu(Gly-Gly)(tmp)]·3.5 H2O and [Cu2Cl4(tmp)2]. The complexes were studied in solution, where the major species are also ternary ones. The lipophilicity of the complexes was determined and the binding to the DNA was evaluated, suggesting that it occurs in the DNA's major groove. The cytotoxicity of the complexes was evaluated on different cancer cell lines: human metastatic breast adenocarcinoma MDA-MB-231 (triple negative, ATCC: HTB-26), MCF-7 (ATCC: HTB-22), SK-BR-3 (ATCC: HTB-30), human lung epithelial carcinoma A549 (ATCC: CCL-185), cisplatin resistant-human ovarian carcinoma A2780cis (SIGMA) and nontumoral cell lines: MRC-5 (lung; ATCC: CCL-171) and MCF-10A (breast, ATCC: CRL-10317). [Cu(L-dipeptide)(tmp)] complexes are highly cytotoxic as compared to [Cu(L-dipeptide)(phenanthroline)] and cisplatin. Therefore, [Cu(L-dipeptide)(tmp)] complexes are promising candidates to have their in vivo activity further studied toward new treatments for triple negative breast cancer and other aggressive tumors for which there is no curative pharmacological treatment to the date.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Neoplasias de la Mama Triple Negativas , Antineoplásicos/farmacología , Cisplatino/farmacología , Complejos de Coordinación/química , Cobre/química , Cobre/farmacología , ADN/química , Dipéptidos/química , Humanos , Células MCF-7 , Fenantrolinas/química
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