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1.
Cell ; 174(5): 1067-1081.e17, 2018 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-30078707

RESUMEN

Long mammalian introns make it challenging for the RNA processing machinery to identify exons accurately. We find that LINE-derived sequences (LINEs) contribute to this selection by recruiting dozens of RNA-binding proteins (RBPs) to introns. This includes MATR3, which promotes binding of PTBP1 to multivalent binding sites within LINEs. Both RBPs repress splicing and 3' end processing within and around LINEs. Notably, repressive RBPs preferentially bind to evolutionarily young LINEs, which are located far from exons. These RBPs insulate the LINEs and the surrounding intronic regions from RNA processing. Upon evolutionary divergence, changes in RNA motifs within LINEs lead to gradual loss of their insulation. Hence, older LINEs are located closer to exons, are a common source of tissue-specific exons, and increasingly bind to RBPs that enhance RNA processing. Thus, LINEs are hubs for the assembly of repressive RBPs and also contribute to the evolution of new, lineage-specific transcripts in mammals. VIDEO ABSTRACT.


Asunto(s)
Ribonucleoproteínas Nucleares Heterogéneas/química , Elementos de Nucleótido Esparcido Largo , Proteínas Asociadas a Matriz Nuclear/química , Poliadenilación , Proteína de Unión al Tracto de Polipirimidina/química , Proteínas de Unión al ARN/química , ARN/química , Empalme Alternativo , Animales , Sitios de Unión , Exones , Células HeLa , Humanos , Intrones , Ratones , Mutación , Motivos de Nucleótidos , Filogenia , Unión Proteica , Mapeo de Interacción de Proteínas , Empalme del ARN
2.
Cell Tissue Res ; 383(2): 617-644, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33201351

RESUMEN

Injuries to the peripheral nervous system remain a large-scale clinical problem. These injuries often lead to loss of motor and/or sensory function that significantly affects patients' quality of life. The current neurosurgical approach for peripheral nerve repair involves autologous nerve transplantation, which often leads to clinical complications. The most pressing need is to increase the regenerative capacity of existing tubular constructs in the repair of large nerve gaps through development of tissue-engineered approaches that can surpass the performance of autografts. To fully realize the clinical potential of nerve conduit technology, there is a need to reconsider design strategies, biomaterial selection, fabrication techniques and the various potential modifications to optimize a conduit microenvironment that can best mimic the natural process of regeneration. In recent years, a significant progress has been made in the designing and functionality of bioengineered nerve conduits to bridge long peripheral nerve gaps in various animal models. However, translation of this work from lab to commercial scale has not been achieve. The current review summarizes recent advances in the development of tissue engineered nerve guidance conduits (NGCs) with regard to choice of material, novel fabrication methods, surface modifications and regenerative cues such as stem cells and growth factors to improve regeneration performance. Also, the current clinical potential and future perspectives to achieve therapeutic benefits of NGCs will be discussed in context of peripheral nerve regeneration.


Asunto(s)
Regeneración Nerviosa/fisiología , Traumatismos de los Nervios Periféricos/fisiopatología , Ingeniería de Tejidos , Andamios del Tejido/química , Investigación Biomédica Traslacional , Animales , Materiales Biocompatibles/farmacología , Humanos
3.
Cell Immunol ; 357: 104198, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32877756

RESUMEN

Calcium plays an important role in regulating cell physiology and immune responses to various pathogens. Our recent work has highlighted the crucial role for calcium homeostasis in dendritic cells and macrophages during various infections. Here we investigated the effect of calcium homeostasis in regulating T cell activation and function during mycobacterial infection. Results show that calcium homeostasis had varied effects in regulating T cell activation and function during mycobacterial infection. This included regulation of the expression of co-stimulatory molecules, cytokine profiles and effector function. A net negative role for Voltage Gated Calcium Channel (VGCC) was observed. Inhibiting VGCC in mycobacteria primed T cells induced increased production of pro-inflammatory cytokines and an increased effector phenotype. Infected macrophages when incubated with VGCC inhibited T cells, induced increased expression of co-stimulatory molecule expression on macrophages, increased the production of pro-inflammatory cytokines and increased autophagy and apoptosis. This collectively led to reduced survival of mycobacteria inside macrophages. The data point towards a fine regulation of protective responses by routes of calcium influx and release that mediate pathogen survival or clearance.


Asunto(s)
Calcio/metabolismo , Infecciones por Mycobacterium/inmunología , Linfocitos T/metabolismo , Animales , Apoptosis/inmunología , Autofagia/inmunología , Calcio/inmunología , Canales de Calcio/metabolismo , Citocinas/inmunología , Femenino , Homeostasis , Interleucina-2/metabolismo , Activación de Linfocitos/inmunología , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C , Mycobacterium/patogenicidad , Mycobacterium tuberculosis/inmunología , Linfocitos T/fisiología , Tuberculosis/inmunología
4.
Mol Biol Rep ; 47(10): 8007-8021, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32888123

RESUMEN

Osteoarthritis (OA) involves gradual destruction of articular cartilagemanifested by pain, stiffness of joints, and impaired movement especially in knees and hips. Non-vascularity of this tissue hinders its self-regenerative capacity and thus, the application of reparative or restorative modalities becomes imperative in OA treatment. In recent years, stem cell-based therapies have been explored as potential modalities for addressing OA complications. While mesenchymal stem cells (MSCs) hold immense promise, the recapitulation of native articular cartilage usingMSCs remains elusive. In this review, we have highlighted the chondrogenic potential of MSCs, factors guiding in vitro chondrogenic differentiation, biomaterials available for cartilage repair, their current market status, and the outcomes of major clinical trials. Our search on ClinicalTrials.gov using terms "stem cell" and "osteoarthritis" yielded 83 results. An analysis of the 29 trials that have been completed revealed differences in source of MSCs (bone marrow, adipose tissue, umbilical cord etc.), cell type (autologous or allogenic), and dose administered. Moreover, only 02 out of 29 studies have reported the use of matrix for cartilage repair. From future perspective, aconsensus on choice of cells, differentiation inducers, biomaterials, and clinical settings might pave a way for concocting robust strategies to improve the clinical applicability of biomimetic neocartilage constructs.


Asunto(s)
Cartílago Articular/metabolismo , Diferenciación Celular , Condrogénesis , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Osteoartritis , Animales , Cartílago Articular/patología , Humanos , Células Madre Mesenquimatosas/patología , Osteoartritis/metabolismo , Osteoartritis/patología , Osteoartritis/terapia
5.
PLoS Comput Biol ; 12(11): e1005203, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27846212

RESUMEN

Quantifying differences or similarities in connectomes has been a challenge due to the immense complexity of global brain networks. Here we introduce a noninvasive method that uses diffusion MRI to characterize whole-brain white matter architecture as a single local connectome fingerprint that allows for a direct comparison between structural connectomes. In four independently acquired data sets with repeated scans (total N = 213), we show that the local connectome fingerprint is highly specific to an individual, allowing for an accurate self-versus-others classification that achieved 100% accuracy across 17,398 identification tests. The estimated classification error was approximately one thousand times smaller than fingerprints derived from diffusivity-based measures or region-to-region connectivity patterns for repeat scans acquired within 3 months. The local connectome fingerprint also revealed neuroplasticity within an individual reflected as a decreasing trend in self-similarity across time, whereas this change was not observed in the diffusivity measures. Moreover, the local connectome fingerprint can be used as a phenotypic marker, revealing 12.51% similarity between monozygotic twins, 5.14% between dizygotic twins, and 4.51% between none-twin siblings, relative to differences between unrelated subjects. This novel approach opens a new door for probing the influence of pathological, genetic, social, or environmental factors on the unique configuration of the human connectome.


Asunto(s)
Encéfalo/anatomía & histología , Conectoma/métodos , Imagen de Difusión Tensora/métodos , Interpretación de Imagen Asistida por Computador/métodos , Técnica de Sustracción , Sustancia Blanca/anatomía & histología , Adulto , Algoritmos , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Reconocimiento de Normas Patrones Automatizadas/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
6.
Bioorg Med Chem Lett ; 24(14): 3137-41, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24856068

RESUMEN

Prompted by the role of PDE5 and its closely associated cAMP and cGMP in hypertension, we have attempted to discover novel PDE5 inhibitors through ligand based virtual screening. Rigorously validated model comprising of one HBA, one HY and one RA was used as a query to search the NCI database leading to retrieval of many compounds which were screened on the basis of estimated activity, fit value and Lipinski's violation. Selected compounds were subjected to docking studies which resulted into visualization of potential interaction capabilities of NCI compounds in line to pharmacophoric features. Finally three compounds were subjected to in vitro evaluation using the isolated rat aortic model. The results showed that all three compounds are potent and novel PDE5 inhibitors with vasodilatory activity range from 10(-2) to 10(-5) M.


Asunto(s)
Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/metabolismo , Evaluación Preclínica de Medicamentos , Simulación del Acoplamiento Molecular , Inhibidores de Fosfodiesterasa 5/farmacología , Vasodilatadores/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Inhibidores de Fosfodiesterasa 5/síntesis química , Inhibidores de Fosfodiesterasa 5/química , Relación Estructura-Actividad , Vasodilatación/efectos de los fármacos , Vasodilatadores/síntesis química , Vasodilatadores/química
7.
ScientificWorldJournal ; 2014: 639682, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24707212

RESUMEN

Synonymous codon usage bias is an inevitable phenomenon in organismic taxa across the three domains of life. Though the frequency of codon usage is not equal across species and within genome in the same species, the phenomenon is non random and is tissue-specific. Several factors such as GC content, nucleotide distribution, protein hydropathy, protein secondary structure, and translational selection are reported to contribute to codon usage preference. The synonymous codon usage patterns can be helpful in revealing the expression pattern of genes as well as the evolutionary relationship between the sequences. In this study, synonymous codon usage bias patterns were determined for the evolutionarily close proteins of albumin superfamily, namely, albumin, α-fetoprotein, afamin, and vitamin D-binding protein. Our study demonstrated that the genes of the four albumin superfamily members have low GC content and high values of effective number of codons (ENC) suggesting high expressivity of these genes and less bias in codon usage preferences. This study also provided evidence that the albumin superfamily members are not subjected to mutational selection pressure.


Asunto(s)
Albúminas/genética , Codón , Humanos , ARN Mensajero/genética
8.
Microbes Infect ; 26(3): 105271, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38036036

RESUMEN

Microorganisms present in the gut modulate host defence responses against infections in order to maintain immune homeostasis. This host-microbe crosstalk is regulated by gut metabolites. Butyrate is one such small chain fatty acid produced by gut microbes upon fermentation that has the potential to influence immune responses. Here we investigated the role of butyrate in macrophages during mycobacterial infection. Results demonstrate that butyrate significantly suppresses the growth kinetics of mycobacteria in culture medium as well as inhibits mycobacterial survival inside macrophages. Interestingly, butyrate alters the pentose phosphate pathway by inducing higher expression of Glucose-6-Phosphate Dehydrogenase (G6PDH) resulting in a higher oxidative burst via decreased Sod-2 and increased Nox-2 (NADPH oxidase-2) expression. Butyrate-induced G6PDH also mediated a decrease in mitochondrial membrane potential. This in turn lead to an induction of apoptosis as measured by lower expression of the anti-apoptotic protein Bcl-2 and a higher release of Cytochrome C as a result of induction of apoptosis. These results indicate that butyrate alters the metabolic status of macrophages and induces protective immune responses against mycobacterial infection.


Asunto(s)
Butiratos , Infecciones por Mycobacterium , Humanos , Butiratos/farmacología , Glucosafosfato Deshidrogenasa/metabolismo , Estallido Respiratorio , Macrófagos/microbiología , Infecciones por Mycobacterium/metabolismo , Apoptosis
9.
Front Public Health ; 12: 1359082, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39045160

RESUMEN

Background: Despite established vaccination programs, vaccine-preventable diseases persist among about 900,000 Forcibly Displaced Myanmar Nationals (FDMN)/Rohingya refugees in the world's largest refugee settlement in Bangladesh. Health service providers (HSPs) play a key role in the delivery of childhood vaccination programs. This study explored their views on individual and context barriers and drivers to childhood vaccination in this setting. Methods: Informed by the theoretical framework of the Capability-Opportunity-Motivation-Behavior (COM-B) model for behavior change, this qualitative study collected data through eight focus group discussions (FGDs) with community health workers (CHWs) and vaccinators in selected camps with high or low vaccination coverage rates, and through 11 in-depth interviews (IDIs) with key informants working in strategic, management, and administrative roles. Findings: Barriers and drivers were evident across all COM factors for HSPs and caregivers. Among HSPs, knowledge around vaccination acted both as a barrier and driver, while communication skills and confidence in vaccination served as drivers. Caregivers' lack of awareness of vaccination, concerns and mistrust were described as main barriers. Context barriers included information system deficiencies, family dynamics, HSPs' working conditions, and vaccination site accessibility. Context drivers included effective communication, mobilization, and incentives. Differences between high and low coverage camps in Cox's Bazar included variations in HSPs' knowledge, communication strategies, incentive use, and stakeholder collaboration. Discussion: For better vaccination coverage in the camps, context-related changes regarding collaboration, health workforce and the use of incentives seem necessary. Caregivers' mistrust toward vaccination needs to be considered under the social and historical background of the Rohingya community, and further addressed with targeted communication and campaigning.


Asunto(s)
Grupos Focales , Investigación Cualitativa , Refugiados , Vacunación , Humanos , Bangladesh , Refugiados/psicología , Refugiados/estadística & datos numéricos , Mianmar , Femenino , Masculino , Adulto , Vacunación/psicología , Vacunación/estadística & datos numéricos , Personal de Salud/psicología , Personal de Salud/estadística & datos numéricos , Persona de Mediana Edad , Conocimientos, Actitudes y Práctica en Salud , Motivación
10.
J Leukoc Biol ; 116(3): 644-656, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-38489665

RESUMEN

Tuberculosis caused by the pathogen Mycobacterium tuberculosis leads to increased mortality and morbidity worldwide. The prevalence of highly drug-resistant strains has reinforced the need for greater understanding of host-pathogen interactions at the cellular and molecular levels. Our previous work demonstrated critical roles of calcium ion channels in regulating protective responses to mycobacteria. In this report, we deciphered the roles of inwardly rectifying K+ ion channel Kir2.1 in epithelial cells. Data showed that infection of epithelial cells (and macrophages) increases the surface expression of Kir2.1. This increased expression of Kir2.1 results in higher intracellular mycobacterial survival, as either inhibiting or knocking down Kir2.1 results in mounting of a higher oxidative burst leading to a significant attenuation of mycobacterial survival. Further, inhibiting Kir2.1 also led to increased expression of T cell costimulatory molecules accompanied with increased activation of MAP kinases and transcription factors nuclear factor κB and phosphorylated CREB. Furthermore, inhibiting Kir2.1 induced increased autophagy and apoptosis that could also contribute to decreased bacterial survival. Interestingly, an increased association of heat shock protein 70 kDa with Kir2.1 was observed. These results showed that mycobacteria modulate the expression and function of Kir2.1 in epithelial cells to its advantage.


Asunto(s)
Mycobacterium bovis , Canales de Potasio de Rectificación Interna , Canales de Potasio de Rectificación Interna/metabolismo , Canales de Potasio de Rectificación Interna/genética , Humanos , Mycobacterium bovis/inmunología , Apoptosis , Animales , Macrófagos/metabolismo , Macrófagos/microbiología , Macrófagos/inmunología , Células Epiteliales/metabolismo , Células Epiteliales/microbiología , Autofagia , FN-kappa B/metabolismo , Ratones , Viabilidad Microbiana
11.
Microbes Infect ; : 105428, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39368609

RESUMEN

Mycobacteria have several mechanisms for evasion of protective responses mounted by the host. In this study, we unravel yet another mechanism that is mediated by Toll-Like Receptors TLR2, TLR4, and TLR7 in epithelial cells. We show that mycobacterial infection of epithelial cells increases the expression of TLR2, TLR4, and TLR7. Stimulation of either TLR along with mycobacterial infection results in an inhibition of oxidative burst resulting in increased survival of mycobacteria inside epithelial cells. TLR stimulation along with mycobacterial infection also inhibits activation of epithelial cells for T cell responses by differentially regulating the activation of ERK-MAPK and p38-MAPK along with inhibition of co-stimulatory molecule CD86 expression. Furthermore, stimulation of either TLR inhibits the induction of apoptosis and autophagy. Knockdown of either TLR by specific siRNAs reverses the inhibition by ROS and apoptosis by mycobacteria and results in reduced intracellular survival of mycobacteria in a MyD88-dependent manner. These results point towards a negative role for TLR2, TLR4, and TLR7 in regulating protective responses to M. bovis BCG infection in epithelial cells.

12.
PLoS One ; 18(7): e0287443, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37437010

RESUMEN

Peer review is the backbone of academia and humans constitute a cornerstone of this process, being responsible for reviewing submissions and making the final acceptance/rejection decisions. Given that human decision-making is known to be susceptible to various cognitive biases, it is important to understand which (if any) biases are present in the peer-review process, and design the pipeline such that the impact of these biases is minimized. In this work, we focus on the dynamics of discussions between reviewers and investigate the presence of herding behaviour therein. Specifically, we aim to understand whether reviewers and discussion chairs get disproportionately influenced by the first argument presented in the discussion when (in case of reviewers) they form an independent opinion about the paper before discussing it with others. In conjunction with the review process of a large, top tier machine learning conference, we design and execute a randomized controlled trial that involves 1,544 papers and 2,797 reviewers with the goal of testing for the conditional causal effect of the discussion initiator's opinion on the outcome of a paper. Our experiment reveals no evidence of herding in peer-review discussions. This observation is in contrast with past work that has documented an undue influence of the first piece of information on the final decision (e.g., anchoring effect) and analyzed herding behaviour in other applications (e.g., financial markets). Regarding policy implications, the absence of the herding effect suggests that the current status quo of the absence of a unified policy towards discussion initiation does not result in an increased arbitrariness of the resulting decisions.


Asunto(s)
Revisión por Pares , Conformidad Social , Humanos
13.
Microbes Infect ; 25(6): 105126, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36931492

RESUMEN

Mycobacterium tuberculosis attenuates many defence responses from alveolar macrophages to create a niche at sites of infection in the human lung. Levels of Heat Shock Proteins have been reported to increase many folds in the serum of active TB patients than in latently infected individuals. Here we investigated the regulation of key defence responses by HSPs during mycobacterial infection. We show that infection of macrophages with M. bovis BCG induces higher expression of HSP-27 and HSP-70. Inhibiting HSP-27 and HSP-70 prior to mycobacterial infection leads to a significant decrease in mycobacterial growth inside macrophages. Further, inhibiting HSPs resulted in a significant increase in intracellular oxidative burst levels. This was accompanied by an increase in the levels of T cell activation molecules CD40 and IL-12 receptor and a concomitant decrease in the levels of T cell inhibitory molecules PD-L1 and IL-10 receptor. Furthermore, inhibiting HSPs significantly increased the expression of key proteins in the autophagy pathway along with increased activation of pro-inflammatory promoting transcription factors NF-κB and p-CREB. Interestingly, we also show that both HSP-27 and HSP-70 are associated with anti-apoptotic proteins Bcl-2 and Beclin-1. These results point towards a suppressive role for host HSP-27 and HSP-70 during mycobacterial infection.


Asunto(s)
Proteínas de Choque Térmico HSP27 , Proteínas HSP70 de Choque Térmico , Macrófagos , Infecciones por Mycobacterium , Mycobacterium tuberculosis , Humanos , Proteínas de Choque Térmico/metabolismo , Macrófagos/microbiología , Infecciones por Mycobacterium/metabolismo , Mycobacterium tuberculosis/patogenicidad , Linfocitos T , Proteínas HSP70 de Choque Térmico/inmunología , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas de Choque Térmico HSP27/inmunología , Proteínas de Choque Térmico HSP27/metabolismo
14.
Biomedicines ; 11(5)2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37239093

RESUMEN

The most frequent neurodegenerative illness among senior people and the main cause of dementia is Alzheimer's disease. The present dementia medications available only help with the symptoms of cognitive deficits and have several negative effects. The current study's goal is to assess the effects of curcumin and coenzyme Q10, two herbal medicines, both separately and in combination, on learning and memory before comparing them to the industry standard drug. A total of 42 adult healthy Wistar rats were used in our study. In this experiment, rats were given daily doses of 2.5 mg/kg of body weight of scopolamine hydrobromide for 7 days to induce Alzheimer's disease. On the eighth day, behavioural testing was conducted. Following testing, scopolamine and the test medications were given daily for the following 21 days. On days 29 and 30, behavioural testing was conducted once more, and then animals were slaughtered. Brain homogenate was produced for the estimation of molecular and biochemical markers. Curcumin has demonstrated a dose-response relationship, with a higher dose (200 mg/kg b.w. p.o.) being more effective than a lower dose (100 mg/kg b.w. p.o.). Similar to the greater dose of curcumin, coenzyme Q10 (200 mg/kg b.w. p.o.) has also been found to improve memory and learning. Higher doses of curcumin and coenzyme Q10 had more pronounced and meaningful effects. Acetylcholinesterase and TNF levels increased in scopolamine-induced memory impairment, but these effects were restored by the test medications, and improved by the combined therapy. These outcomes are comparable to those of the common medication memantine. As a result, we may infer from our results that curcumin at higher doses and its combination with coenzyme Q10 (200 mg/kg b.w. p.o.) have a significant impact on cognitive impairment in animal models of Alzheimer's disease and can be utilised alone or as an add-on therapy for the condition.

15.
Br J Pharmacol ; 179(10): 2081-2085, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34632567

RESUMEN

Pyroptosis is a specialized form of inflammatory cell death which aids the defensive response against invading pathogens. Its normally tight regulation is lost during infection by the severe acute respiratory coronavirus 2 (SARS-CoV-2), and thus, uncontrolled pyroptosis disrupts the immune system and the integrity of organs defining the critical conditions in patients with high viral load. Molecular pathways engaged downstream of the formation and stabilization of the inflammasome, which are necessary to execute the process, have been uncovered and drugs are available for their regulation. However, the pharmacology of the upstream events, which are critical to sense and interpret the initial damage by the pathogen, is far from being elucidated. This limits our capacity to identify early markers and targets to ameliorate SARS-CoV-2 linked pyroptosis. Here, we focus attention on the mitochondria and pathways leading to their dysfunction, in order to elucidate the early steps of inflammasome formation and devise tools to predict and counter pathological states induced by SARS-CoV-2. LINKED ARTICLES: This article is part of a themed issue on The second wave: are we any closer to efficacious pharmacotherapy for COVID 19? (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.10/issuetoc.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Humanos , Inflamasomas , Mitocondrias , Piroptosis , SARS-CoV-2
16.
Biomed Mater ; 17(6)2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36044885

RESUMEN

Nanoconfinement within flexible interfaces is a key step towards exploiting confinement effects in several biological and technological systems wherein flexible 2D materials are frequently utilized but are arduous to prepare. Hitherto unreported, the synthesis of 2D hydrogel nanosheets (HNSs) using a template- and catalyst-free process is developed representing a fertile ground for fundamental structure-property investigations. In due course of time, nucleating folds propagating along the edges trigger co-operative deformations of HNS generating regions of nanoconfinement within trapped water islands. These severely constricting surfaces force water molecules to pack within the nanoscale regime of HNS almost parallel to the surface bringing about phase transition into puckered rhombic ice with AA and AB Bernal stacking pattern, which was mostly restricted to molecular dynamics studies so far. Interestingly, under high lateral pressure and spatial inhomogeneity within nanoscale confinement, bilayer rhombic ice structures were formed with an in-plane lattice spacing of 0.31 nm. In this work, a systematic exploration of rhombic ice formation within HNS has been delineated using high-resolution transmission electron microscopy, and its ultrathin morphology was examined using atomic force microscopy. Scanning electron microscopy images revealed high porosity while mechanical testing presented young's modulus of 155 kPa with ∼84% deformation, whereas contact angle suggested high hydrophilicity. The combinations of nanosheets, porosity, nanoconfinement, hydrophilicity, and mechanical strength, motivated us to explore their application as a scaffold for cartilage regeneration, by inducing chondrogenesis of human Wharton Jelly derived mesenchymal stem cells. HNS promoted the formation of cell aggregates giving higher number of spheroid formation and a marked expression of chondrogenic markers (ColI, ColII, ColX, ACAN and S-100), thereby providing some cues for guiding chondrogenic differentiation.


Asunto(s)
Células Madre Mesenquimatosas , Gelatina de Wharton , Diferenciación Celular , Células Cultivadas , Condrogénesis , Humanos , Hidrogeles/química , Hielo
17.
EBioMedicine ; 65: 103244, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33647769

RESUMEN

Mitochondria play a vital role in cellular metabolism and are central mediator of intracellular signalling, cell differentiation, morphogenesis and demise. An increasingly higher number of pathologies is linked with mitochondrial dysfunction, which can arise from either genetic defects affecting core mitochondrial components or malfunctioning pathways impairing mitochondrial homeostasis. As such, mitochondria are considered an important target in several pathologies spanning from neoplastic to neurodegenerative diseases as well as metabolic syndromes. In this review we provide an overview of the state-of-the-art in mitochondrial pharmacology, focusing on the novel compounds that have been generated in the bid to correct mitochondrial aberrations. Our work aims to serve the scientific community working on translational medical science by highlighting the most promising pharmacological approaches to target mitochondrial dysfunction in disease.


Asunto(s)
Antioxidantes/uso terapéutico , Mitocondrias/metabolismo , Enfermedades Mitocondriales/tratamiento farmacológico , Antioxidantes/farmacología , Humanos , Mitocondrias/efectos de los fármacos , Enfermedades Mitocondriales/patología , Dinámicas Mitocondriales/efectos de los fármacos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/patología , Fosforilación Oxidativa/efectos de los fármacos , Pirazinas/farmacología , Pirazinas/uso terapéutico , Ubiquinona/análogos & derivados , Ubiquinona/farmacología , Ubiquinona/uso terapéutico
18.
ACS Appl Bio Mater ; 4(8): 6304-6315, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35006875

RESUMEN

Concerning the climate crisis, energy disaster, and greenhouse effects, microalgae have paved the way for consideration as a biofuel feed material. The advent of polymeric materials with unique architecture at nanoscale, in combination with microalgae, has given direction for the bioeconomic yield of highly valued compounds, essentially lipid. Herein, we discuss the paramount significance of exotic hydrogel matrix (HM) with efficient violet light absorption, far-red emission, CO2-adsorbing capability and catalyst-free condition that could increase the photosynthesis activity, alleviating the microalgal growth for the effective augmentation of lipid, protein, and chlorophyll. The intrinsic morphological and structural features of HM were revealed by a suite of characterizations that confirm its hollow tubular architecture. Fluorescence intensity measurement confirmed the electron transfer from HM to Chlorella sorokiniana, accelerating the photosynthetic rate for the improved production of lipids (98%), proteins (60%), and chlorophyll a (121%), compared to untreated C. sorokiniana control cells. Moreover, by visualizing the Nile red (NR) fluorescence response from C. sorokiniana/HM cells, a high lipid content was observed with a larger cell size (14.6 µm) compared to control cells (8.7 µm). Fatty acid methyl esters (FAMEs), obtained from C. sorokiniana/HM, were noted with a large-scale volume of C16:C18 fatty acids (>80%). We, therefore, envisage that HM plays a significant role in enhancing the generation of lipids and proteins from C. sorokiniana. These outcomes assure a qualitative transit in the bioenergy domain.


Asunto(s)
Chlorella , Microalgas , Biomasa , Clorofila A/metabolismo , Ácidos Grasos/metabolismo , Hidrogeles/metabolismo
19.
J Dent Anesth Pain Med ; 21(6): 565-574, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34909474

RESUMEN

BACKGROUND: Trigeminal neuralgia (TN) is a severe form of pain that affects the daily activities of a patient. Transcutaneous electrical nerve stimulation (TENS) therapy is an emerging option for the treatment of acute and chronic pain. The aim of this study was to evaluate the effect of TENS therapy as an adjunct to drug therapy for the treatment of TN. METHODS: A total of 52 patients diagnosed with TN according to the International Classification of Headache Disorders (version 3) were included. Each patient was randomized to either the TENS or placebo TENS groups. Intervention was given in continuous mode and 100-Hz frequency for 20 mins biweekly for 6 weeks. Parameters were measured at baseline, TENS completion and 3 months, 6 months, and 1 year of follow up. The parameters observed were mean carbamazepine dose, mean visual analog scale (VAS) score, mean present pain intensity (PPI) score, and functional outcome. Non-parametric analyses, one-way ANOVA and the Kruskal-Wallis test were applied for intragroup comparisons, while the Mann-Whitney U test and independent t-test were used for intergroup comparisons of variables. The chi-square test was applied to analyze categorical data. RESULTS: Compared to the placebo TENS group, the mean dose of carbamazepine in the TENS group was significantly reduced at TENS completion, as well as at 6 months and 1 year follow up. Changes in mean VAS score, mean PPI score, and functional outcome did not show significant differences between the groups (P>0.05). CONCLUSION: TENS therapy does not lead to any changes in pain levels but it may reduce the mean dose of carbamazepine when used as an adjunct treatment in patients with TN.

20.
ACS Omega ; 5(38): 24239-24246, 2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-33015440

RESUMEN

Wound is the major health problem associated with skin damages and arises because of various types of topical injuries. Furthermore, wounds in patients with diabetes take a relatively long time to heal. Currently, herbal medicines have been extensively used for wound care and management. Here, we engineered polymeric hybrid hydrogel of dimethylaminoethyl acrylate and hyaluronic acid (pDMAEMA-HA), which was impregnated with a herbal extract of Didymocarpus pedicellatus. The developed polymeric hybrid hydrogel system can be used for effective therapy of incurable wounds. Therefore, the development of D. pedicellatus-impregnated pDMAEMA-HA (pDPi-DMAEMA-HA) hybrid hydrogel was accomplished by the synthesis of pDMAEMA-HA hydrogel via the optimization of various reaction parameters followed by impregnation of herbal drugs D. pedicellatus. The developed hydrogel composite was well characterized via various techniques, and swelling kinetics was performed to analyze the water uptake property. The swelling ratio was found to be 1600% in both types of hydrogels. To evaluate the wound healing of these polymeric hydrogels, the Wistar rats full-thickness excision wound model was utilized. The healing strength of hydrogels was determined using measurement of wound contraction and histopathological study. The results of wound healing by these polymeric hydrogels revealed that animals treated with the pDPi-DMAEMA-HA hybrid hydrogel group were found to have a higher level of wound closure as compared to marketed formulation as well as polymeric hybrid hydrogel. The histopathologic examinations implied that pDPi-DMAEMA-HA hybrid hydrogel and polymeric hybrid hydrogel-treated groups exhibited enhanced cutaneous wound repair as well as high level of cellular repair and maintenance compared to the standard group because of hyaluronic acid roles in various stages of wound repair.

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