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1.
BMC Microbiol ; 24(1): 320, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39227770

RESUMO

Tuberculosis (TB) remains a major global health concern, with drug-resistant strains posing a significant challenge to effective treatment. Bacteriophage (phage) therapy has emerged as a potential alternative to combat antibiotic resistance. In this study, we investigated the efficacy of widely used mycobacteriophages (D29, TM4, DS6A) against Mycobacterium tuberculosis (M. tuberculosis) under pathophysiological conditions associated with TB, such as low pH and hypoxia. We found that even at low multiplicity of infection (MOI), mycobacteriophages effectively infected M. tuberculosis, got rapidly amplified, and lysed M. tuberculosis, demonstrating their potential as therapeutic agents. Furthermore, we observed a novel phage tolerance mechanism with bacteria forming aggregates after several days of phage treatment. These aggregates were enriched with biofilm components and metabolically active bacteria. However, no phage tolerance was observed upon treatment with the three-phage mixture, highlighting the dynamic interplay between phages and bacteria and emphasizing the importance of phage cocktails. We also observed that phages were effective in lysing bacteria even under low pH and low oxygen concentrations as well as antibiotic-resistant bacteria. Our results provide key insights into phage infection of slow-growing bacteria and suggest that mycobacteriophages can effectively eliminate M. tuberculosis in complex pathophysiological environments like hypoxia and acidic pH. These results can aid in developing targeted phage-based therapies to combat antibiotic-resistant mycobacterial infections.


Assuntos
Micobacteriófagos , Mycobacterium tuberculosis , Terapia por Fagos , Mycobacterium tuberculosis/virologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/patogenicidade , Micobacteriófagos/fisiologia , Concentração de Íons de Hidrogênio , Tuberculose/microbiologia , Tuberculose/terapia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Humanos
2.
Clin Microbiol Rev ; 35(1): e0012321, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-34788128

RESUMO

Respiratory viral pathogens like influenza and coronaviruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have caused outbreaks leading to millions of deaths. Vaccinations are, to date, the best and most economical way to control such outbreaks and have been highly successful for several pathogens. Currently used vaccines for respiratory viral pathogens are primarily live attenuated or inactivated and can risk reversion to virulence or confer inadequate immunity. The recent trend of using potent biomolecules like DNA, RNA, and protein antigenic components to synthesize vaccines for diseases has shown promising results. Still, it remains challenging to translate due to their high susceptibility to degradation during storage and after delivery. Advances in bioengineering technology for vaccine design have made it possible to control the physicochemical properties of the vaccines for rapid synthesis, heightened antigen presentation, safer formulations, and more robust immunogenicity. Bioengineering techniques and materials have been used to synthesize several potent vaccines, approved or in trials, against coronavirus disease 2019 (COVID-19) and are being explored for influenza, SARS, and Middle East respiratory syndrome (MERS) vaccines as well. Here, we review bioengineering strategies such as the use of polymeric particles, liposomes, and virus-like particles in vaccine development against influenza and coronaviruses and the feasibility of adopting these technologies for clinical use.


Assuntos
COVID-19 , Desenvolvimento de Vacinas , Bioengenharia , Humanos , SARS-CoV-2 , Vacinação
3.
Proc Natl Acad Sci U S A ; 117(17): 9477-9482, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32300016

RESUMO

Resolution of intestinal inflammation and wound repair are active processes that mediate epithelial healing at mucosal surfaces. Lipid molecules referred to as specialized proresolving mediators (SPMs) play an important role in the restorative response. Resolvin E1 (RvE1), a SPM derived from omega-3 fatty acids, has been reported to dampen intestinal inflammation by promoting anti-inflammatory responses including increased neutrophil spherocytosis and macrophage production of IL-10. Despite these observations, a role for RvE1 in regulating intestinal epithelial cell migration and proliferation during mucosal wound repair has not been explored. Using an endoscopic biopsy-based wound healing model, we report that RvE1 is locally produced in response to intestinal mucosal injury. Exposure of intestinal epithelial cells to RvE1 promoted wound repair by increasing cellular proliferation and migration through activation of signaling pathways including CREB, mTOR, and Src-FAK. Additionally, RvE1-triggered activation of the small GTPase Rac1 led to increased intracellular reactive oxygen species (ROS) production, cell-matrix adhesion, and cellular protrusions at the leading edge of migrating cells. Furthermore, in situ administration of RvE1-encapsulated synthetic targeted polymeric nanoparticles into intestinal wounds promoted mucosal repair. Together, these findings demonstrate that RvE1 functions as a prorepair lipid mediator by increasing intestinal epithelial cell migration and proliferation, and highlight potential therapeutic applications for this SPM to promote mucosal healing in the intestine.


Assuntos
Ácido Eicosapentaenoico/análogos & derivados , Mucosa Intestinal/metabolismo , Cicatrização/fisiologia , Animais , Adesão Celular , Linhagem Celular , Colo , Ácido Eicosapentaenoico/metabolismo , Ácido Eicosapentaenoico/farmacologia , Humanos , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas , Neuropeptídeos , Organoides , Espécies Reativas de Oxigênio , Proteínas rac1 de Ligação ao GTP
4.
Crit Rev Microbiol ; 47(4): 461-478, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33818246

RESUMO

Intracellular pathogens reside in specialised compartments within the host cells restricting the access of antibiotics. Insufficient intracellular delivery of antibiotics along with several other resistance mechanisms weaken the efficacy of current therapies. An alternative to antibiotic therapy could be bacteriophage (phage) therapy. Although phage therapy has been in practice for a century against various bacterial infections, the efficacy of phages against intracellular bacteria is still being explored. In this review, we will discuss the advancement and challenges in phage therapy, particularly against intracellular bacterial pathogens. Finally, we will highlight the uptake mechanisms and approaches to overcome the challenges to phage therapy against intracellular bacteria.


Assuntos
Bactérias/virologia , Infecções Bacterianas/terapia , Bacteriófagos/fisiologia , Terapia por Fagos , Animais , Bactérias/genética , Infecções Bacterianas/microbiologia , Fenômenos Fisiológicos Bacterianos , Bacteriófagos/genética , Humanos
5.
Proc Natl Acad Sci U S A ; 115(22): E4960-E4969, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29760099

RESUMO

Orthopedic implant infections are a significant clinical problem, with current therapies limited to surgical debridement and systemic antibiotic regimens. Lysostaphin is a bacteriolytic enzyme with high antistaphylococcal activity. We engineered a lysostaphin-delivering injectable PEG hydrogel to treat Staphylococcus aureus infections in bone fractures. The injectable hydrogel formulation adheres to exposed tissue and fracture surfaces, ensuring efficient, local delivery of lysostaphin. Lysostaphin encapsulation within this synthetic hydrogel maintained enzyme stability and activity. Lysostaphin-delivering hydrogels exhibited enhanced antibiofilm activity compared with soluble lysostaphin. Lysostaphin-delivering hydrogels eradicated S. aureus infection and outperformed prophylactic antibiotic and soluble lysostaphin therapy in a murine model of femur fracture. Analysis of the local inflammatory response to infections treated with lysostaphin-delivering hydrogels revealed indistinguishable differences in cytokine secretion profiles compared with uninfected fractures, demonstrating clearance of bacteria and associated inflammation. Importantly, infected fractures treated with lysostaphin-delivering hydrogels fully healed by 5 wk with bone formation and mechanical properties equivalent to those of uninfected fractures, whereas fractures treated without the hydrogel carrier were equivalent to untreated infections. Finally, lysostaphin-delivering hydrogels eliminate methicillin-resistant S. aureus infections, supporting this therapy as an alternative to antibiotics. These results indicate that lysostaphin-delivering hydrogels effectively eliminate orthopedic S. aureus infections while simultaneously supporting fracture repair.


Assuntos
Antibacterianos/administração & dosagem , Consolidação da Fratura/efeitos dos fármacos , Hidrogéis/uso terapêutico , Lisostafina/administração & dosagem , Infecções Relacionadas à Prótese , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Materiais Biocompatíveis/uso terapêutico , Modelos Animais de Doenças , Fraturas do Fêmur/cirurgia , Lisostafina/farmacologia , Lisostafina/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Desenho de Prótese , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus
6.
J Org Chem ; 85(10): 6408-6419, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32321244

RESUMO

High-valent chiral oxidovanadium(V) complexes derived from 3,5-substituted-N-salicylidene-l-tert-leucine were used as catalysts in asymmetric reduction of N-benzyl-ß-ketoamides. Among six different solvents, three different alcohol additives, and two different boranes examined, the use of pinacolborane in tetrahydrofuran (THF) with a t-BuOH additive led to the best results at -20 °C. The corresponding ß-hydroxyamides can be furnished with yields up to 92% and an enantiomeric excess (ee) up to 99%. We have successfully extended this catalytic protocol for the synthesis of an (S)-duloxetine precursor.

7.
Sensors (Basel) ; 18(10)2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30308942

RESUMO

The Internet of Things (IoT) concept has attracted a lot of attention from the research and innovation community for a number of years already. One of the key drivers for this hype towards the IoT is its applicability to a plethora of different application domains. However, infrastructures enabling experimental assessment of IoT solutions are scarce. Being able to test and assess the behavior and the performance of any piece of technology (i.e., protocol, algorithm, application, service, etc.) under real-world circumstances is of utmost importance to increase the acceptance and reduce the time to market of these innovative developments. This paper describes the federation of eleven IoT deployments from heterogeneous application domains (e.g., smart cities, maritime, smart building, crowd-sensing, smart grid, etc.) with over 10,000 IoT devices overall which produce hundreds of thousands of observations per day. The paper summarizes the resources that are made available through a cloud-based platform. The main contributions from this paper are twofold. In the one hand, the insightful summary of the federated data resources are relevant to the experimenters that might be seeking for an experimental infrastructure to assess their innovations. On the other hand, the identification of the challenges met during the testbed integration process, as well as the mitigation strategies that have been implemented to face them, are of interest for testbed providers that can be considering to join the federation.

8.
Proc Natl Acad Sci U S A ; 110(43): 17247-52, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24101456

RESUMO

Size, surface charge, and material compositions are known to influence cell uptake of nanoparticles. However, the effect of particle geometry, i.e., the interplay between nanoscale shape and size, is less understood. Here we show that when shape is decoupled from volume, charge, and material composition, under typical in vitro conditions, mammalian epithelial and immune cells preferentially internalize disc-shaped, negatively charged hydrophilic nanoparticles of high aspect ratios compared with nanorods and lower aspect-ratio nanodiscs. Endothelial cells also prefer nanodiscs, however those of intermediate aspect ratio. Interestingly, unlike nanospheres, larger-sized hydrogel nanodiscs and nanorods are internalized more efficiently than their smallest counterparts. Kinetics, efficiency, and mechanisms of uptake are all shape-dependent and cell type-specific. Although macropinocytosis is used by both epithelial and endothelial cells, epithelial cells uniquely internalize these nanoparticles using the caveolae-mediated pathway. Human umbilical vein endothelial cells, on the other hand, use clathrin-mediated uptake for all shapes and show significantly higher uptake efficiency compared with epithelial cells. Using results from both upright and inverted cultures, we propose that nanoparticle internalization is a complex manifestation of three shape- and size-dependent parameters: particle surface-to-cell membrane contact area, i.e., particle-cell adhesion, strain energy for membrane deformation, and sedimentation or local particle concentration at the cell membrane. These studies provide a fundamental understanding on how nanoparticle uptake in different mammalian cells is influenced by the nanoscale geometry and is critical for designing improved nanocarriers and predicting nanomaterial toxicity.


Assuntos
Endocitose , Hidrogéis/metabolismo , Nanopartículas/metabolismo , Nanosferas/metabolismo , Cavéolas/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Células Cultivadas , Clatrina/metabolismo , Células Endoteliais/metabolismo , Células Epiteliais/metabolismo , Células HEK293 , Células HeLa , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hidrogéis/química , Hidrogéis/farmacocinética , Cinética , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanosferas/química , Nanosferas/ultraestrutura , Tamanho da Partícula , Pinocitose
9.
Chem Commun (Camb) ; 60(13): 1727-1730, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38240148

RESUMO

Hydrogen sulfide (H2S) and associated sulfur species known as persulfide or sulfane sulfur are considered among the first responders to oxidative stress. However, tools that reliably generate these species without any potentially toxic byproducts are limited, and even fewer report the generation of a persulfide. Here, using a latent fluorophore embedded with N-acetylcysteine persulfide, we report a new tool that is cleaved by esterase to produce a persulfide as well as a fluorescence reporter without any electrophilic byproducts. The rate of formation of the fluorescence reporter is nearly identical to the rate of formation of the persulfide suggesting that the use of this probe eliminates the need for secondary assays that report persulfide formation. Symptomatic with persulfide generation, the newly developed donor was able to protect chondrocyte cells from oxidative stress.


Assuntos
Esterases , Sulfeto de Hidrogênio , Fluorescência , Sulfetos , Enxofre
10.
Ann Afr Med ; 23(4): 635-640, 2024 Oct 01.
Artigo em Francês, Inglês | MEDLINE | ID: mdl-39138974

RESUMO

BACKGROUND: Diffusion-weighted imaging (DWI) has come up as a newer diagnostic modality for the diagnosis of early functional changes in various organs including the pancreas. DWI has shown the ability of early and accurate diagnosis of inflammatory pathologies, before the appearance of morphological changes on imaging. OBJECTIVES: The objectives of this study were to study the diagnostic accuracy of DWI in the diagnosis of early acute interstitial pancreatitis. MATERIALS AND METHODS: The present retrospective observational study was conducted at the department of radiodiagnosis of a tertiary teaching hospital for 1 year. Fifty patients who underwent magnetic resonance imaging of the pancreas with clinical or laboratory diagnosis of early pancreatitis were included in the study. The diagnostic accuracy of DWI was analyzed on the basis of quantitative (apparent diffusion coefficient [ADC] values) evaluation in the diagnosis of early acute pancreatitis. Threshold values for ADC were derived for differentiation of inflamed versus normal pancreas. Sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) were obtained by drawing the receiver operating characteristic (ROC) curve. RESULTS: The mean ADC values in the patient group (0.882 × 10 -3 mm 2 /s ± 0.102) were significantly lower than the control group (1.178 × 10 -3 mm 2 /s ± 0.232) with P < 0.001. The ROC curve deciphered a cutoff value of 0.937 × 10 -3 mm 2 /s with a sensitivity of 84%, specificity of 86%, PPV of 85.71%, and NPV of 84.31% for diagnosis of acute pancreatitis using quantitative ADC values. CONCLUSION: DWI can thus be a succinct modality for early diagnosis of pancreatitis with excellent diagnostic accuracy and superlative advantage of lack of contrast and radiation in comparison to computed tomography scan.


Résumé Contexte:L'imagerie pondérée en diffusion (DWI) est apparue comme une nouvelle modalité de diagnostic pour le diagnostic des changements fonctionnels précoces.dans divers organes, dont le pancréas. DWI a montré la capacité de diagnostic précoce et précis des pathologies inflammatoires, avant apparition de modifications morphologiques à l'imagerie.Objectifs:Les objectifs de cette étude étaient d'étudier la précision diagnostique du CFA chez le diagnostic de pancréatite interstitielle aiguë précoce.Matériels et méthodes:La présente étude observationnelle rétrospective a été menée à le service de radiodiagnostic d'un CHU pendant 1 an. Cinquante patients ayant bénéficié d'une imagerie par résonance magnétique du les pancréas présentant un diagnostic clinique ou de laboratoire de pancréatite précoce ont été inclus dans l'étude. La précision diagnostique du DWI a été analysée sur la base d'une évaluation quantitative (valeurs du coefficient de diffusion apparent [ADC]) dans le diagnostic de la pancréatite aiguë précoce. Seuil les valeurs de l'ADC ont été dérivées pour différencier le pancréas enflammé du pancréas normal. Sensibilité, spécificité, valeur prédictive positive (VPP),et des valeurs prédictives négatives (NPV) ont été obtenues en traçant la courbe des caractéristiques de fonctionnement du récepteur (ROC).Résultats:L'ADC moyenles valeurs du groupe de patients (0.882 × 10−3 mm2/s ± 0.102) étaient significativement inférieures à celles du groupe témoin (1.178 × 10−3 mm2/s ± 0.232) avec P < 0.001. La courbe ROC a décrypté une valeur seuil de 0.937 × 10−3 mm2/s avec une sensibilité de 84 %, une spécificité de 86 %, une VPP de 85.71 %, et VPN de 84.31 % pour le diagnostic de pancréatite aiguë à l'aide des valeurs quantitatives de l'ADC.Conclusion:La DWI peut donc être une modalité succincte pour le diagnostic précoce de la pancréatite avec une excellente précision diagnostique et l'avantage exceptionnel de l'absence de contraste et de rayonnement par rapport à la tomodensitométrie.


Assuntos
Imagem de Difusão por Ressonância Magnética , Pancreatite , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Retrospectivos , Feminino , Masculino , Pancreatite/diagnóstico por imagem , Pancreatite/diagnóstico , Pessoa de Meia-Idade , Adulto , Doença Aguda , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Curva ROC , Diagnóstico Precoce , Idoso
11.
Adv Healthc Mater ; : e2304299, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38655817

RESUMO

The mortality caused by tuberculosis (TB) infections is a global concern, and there is a need to improve understanding of the disease. Current in vitro infection models to study the disease have limitations such as short investigation durations and divergent transcriptional signatures. This study aims to overcome these limitations by developing a 3D collagen culture system that mimics the biomechanical and extracellular matrix (ECM) of lung microenvironment (collagen fibers, stiffness comparable to in vivo conditions) as the infection primarily manifests in the lungs. The system incorporates Mycobacterium tuberculosis (Mtb) infected human THP-1 or primary monocytes/macrophages. Dual RNA sequencing reveals higher mammalian gene expression similarity with patient samples than 2D macrophage infections. Similarly, bacterial gene expression more accurately recapitulates in vivo gene expression patterns compared to bacteria in 2D infection models. Key phenotypes observed in humans, such as foamy macrophages and mycobacterial cords, are reproduced in the model. This biomaterial system overcomes challenges associated with traditional platforms by modulating immune cells and closely mimicking in vivo infection conditions, including showing efficacy with clinically relevant concentrations of anti-TB drug pyrazinamide, not seen in any other in vitro infection model, making it reliable and readily adoptable for tuberculosis studies and drug screening.

12.
Bioeng Transl Med ; 8(1): e10298, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684078

RESUMO

Trauma to the knee joint is associated with significant cartilage degeneration and erosion of subchondral bone, which eventually leads to osteoarthritis (OA), resulting in substantial morbidity and healthcare burden. With no disease-modifying drugs in clinics, the current standard of care focuses on symptomatic relief and viscosupplementation. Modulation of autophagy and targeting senescence pathways are emerging as potential treatment strategies. Rapamycin has shown promise in OA disease amelioration by autophagy upregulation, yet its clinical use is hindered by difficulties in achieving therapeutic concentrations, necessitating multiple weekly injections. Rapamycin-loaded in poly(lactic-co-glycolic acid) microparticles (RMPs) induced autophagy, prevented senescence, and sustained sulphated glycosaminoglycans production in primary human articular chondrocytes from OA patients. RMPs were potent, nontoxic, and exhibited high retention time (up to 35 days) in mice joints. Intra-articular delivery of RMPs effectively mitigated cartilage damage and inflammation in surgery-induced OA when administered as a prophylactic or therapeutic regimen. Together, the study demonstrates the feasibility of using RMPs as a potential clinically translatable therapy to prevent the progression of post-traumatic OA.

13.
J Clin Exp Hepatol ; 13(2): 196-202, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36950487

RESUMO

Objectives: Psoas muscle parameters have been proposed as a simple and quick method for sarcopenia assessment. The aim of this study was to assess sarcopenia in cirrhotics by psoas muscle on computed tomography and its impact on mortality. Methods: One hundred and fifty patients (75 cirrhotics, 75 subjects) were assessed for psoas muscle on CT scan. Psoas muscle index (PMI) was calculated as 'total psoas muscle area/(height of subject)2'. Cut off values for sarcopenia diagnosis were derived from local subjects (n = 75) who did not have cirrhosis/other causes of sarcopenia. Results: Sarcopenia assessed by PMI was seen in 36% (n = 27) of the cirrhotics. Sarcopenia was significantly higher in patients having Child-Pugh C. Ascites, hepatic encephalopathy (HE) and gastro-intestinal bleed were seen in 48%, 18.7% and 24%, respectively. Sarcopenia was significantly associated with ascites and HE (P < 0.05). Out of the 75 cases, 53 cases completed the follow-up period of 1 year. Among the 20 cases who had sarcopenia, 35% (n = 7) succumbed to liver-related illness during 1 year follow-up, and out of the 33 cases without sarcopenia, only 6% (n = 2) died. The association of sarcopenia and 1 year mortality was statistically significant (P = 0.01). Conclusions: The PMI, a simple method for sarcopenia assessment detected sarcopenia in 36% of cirrhotics. Patients with sarcopenia had a significantly higher 1 year mortality rate and appropriate prognostication of such patients is needed.

14.
J Biomed Mater Res A ; 111(6): 765-777, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36773024

RESUMO

Osteoarthritis (OA) is the most common joint disorder and currently affects >500 million patients worldwide, with ~60% of them also suffering from obesity. There is no drug approved for human use that changes the course of OA progression. OA is one of the most common comorbidities of obesity, and obesity-related OA (ObOA) is a serious health concern because it shows heightened severity of tissue damage and also predominantly affects the working population. Unresolved inflammation is a major driver of ObOA, thus, resolving disease-associated inflammation is a viable strategy to treat ObOA. Resolvins are highly potent molecules that play a role in the resolution of inflammation and promote tissue healing. However, small molecules (like Resolvin D1; RvD1) have to be administered frequently or prior to injury because they lose their in vivo activity rapidly either by lymphatic clearance, or oxidation-mediated deactivation. In this study, we have encapsulated RvD1 in liposomes and established its efficacy in the mouse model of ObOA at much lower dosages than freely administered RvD1. Liposomal RvD1 (lipo-RvD1) acted as a source of the RvD1 molecules for ~11 days in vitro in synovial fluid derived from patients. When administered prophylactically or therapeutically, lipo-RvD1 suppressed cartilage damage in male C57BL/6 mice compared to untreated and free RvD1 treatments. This efficacy was achieved by increasing the proportion of the proresolution M2 macrophages over proinflammatory M1 macrophages in the synovial membrane. These results show the potential of lipo-RvD1 as an anti-OA agent.


Assuntos
Lipossomos , Osteoartrite , Camundongos , Animais , Humanos , Masculino , Camundongos Obesos , Preparações de Ação Retardada/farmacologia , Preparações de Ação Retardada/uso terapêutico , Camundongos Endogâmicos C57BL , Osteoartrite/tratamento farmacológico , Inflamação/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Docosa-Hexaenoicos/uso terapêutico , Obesidade/complicações , Obesidade/tratamento farmacológico
15.
Cell Rep Med ; 4(8): 101127, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37463584

RESUMO

The COVID-19 pandemic highlights an urgent need for effective antivirals. Targeting host processes co-opted by viruses is an attractive antiviral strategy with a high resistance barrier. Picolinic acid (PA) is a tryptophan metabolite endogenously produced in mammals. Here, we report the broad-spectrum antiviral activity of PA against enveloped viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A virus (IAV), flaviviruses, herpes simplex virus, and parainfluenza virus. Mechanistic studies reveal that PA inhibits enveloped virus entry by compromising viral membrane integrity, inhibiting virus-cellular membrane fusion, and interfering with cellular endocytosis. More importantly, in pre-clinical animal models, PA exhibits promising antiviral efficacy against SARS-CoV-2 and IAV. Overall, our data establish PA as a broad-spectrum antiviral with promising pre-clinical efficacy against pandemic viruses SARS-CoV-2 and IAV.


Assuntos
COVID-19 , Vírus da Influenza A , Animais , Humanos , SARS-CoV-2/metabolismo , Internalização do Vírus , Pandemias , Replicação Viral , Antivirais/farmacologia , Antivirais/uso terapêutico , Mamíferos/metabolismo
16.
Bioeng Transl Med ; 7(2): e10281, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35600665

RESUMO

Current treatments for osteoarthritis (OA) offer symptomatic relief but do not prevent or halt the disease progression. Chronic low-grade inflammation is considered a significant driver of OA. Specialized proresolution mediators are powerful agents of resolution but have a short in vivo half-life. In this study, we have engineered a Resolvin D1 (RvD1)-loaded nanoliposomal formulation (Lipo-RvD1) that targets and resolves the OA-associated inflammation. This formulation creates a depot of the RvD1 molecules that allows the controlled release of the molecule for up to 11 days in vitro. In surgically induced mice model of OA, only controlled-release formulation of Lipo-RvD1 was able to treat the progressing cartilage damage when administered a month after the surgery, while the free drug was unable to prevent cartilage damage. We found that Lipo-RvD1 functions by damping the proinflammatory activity of synovial macrophages and recruiting a higher number of M2 macrophages at the site of inflammation. Our Lipo-RvD1 formulation was able to target and suppress the formation of the osteophytes and showed analgesic effect, thus emphasizing its ability to treat clinical symptoms of OA. Such controlled-release formulation of RvD1 could represent a patient-compliant treatment for OA.

17.
Biomater Adv ; 133: 112612, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35527151

RESUMO

Inhalable microparticle-based drug delivery platforms are being investigated extensively for Tuberculosis (TB) treatment as they offer efficient deposition in lungs and improved pharmacokinetics of the encapsulated cargo. However, the effect of physical parameters of microcarriers on interaction with Mycobacterium tuberculosis (Mtb) infected mammalian cells is underexplored. In this study, we report that Mtb-infected macrophages are highly phagocytic and microparticle surface charge plays a major role in particle internalization by infected cells. Microparticles of different sizes (0.5-2 µm) were internalized in large numbers by Mtb-infected THP-1 macrophages and murine primary Bone Marrow Derived Macrophages in vitro. Drastic improvement in particle uptake was observed with cationic particles in vitro and in mice lungs. Rapid uptake of rifampicin-loaded cationic microparticles allowed high intracellular accumulation of the drug and led to enhanced anti-bacterial function when compared to non-modified rifampicin-loaded microparticles. Cytocompatibility assay and histological analysis in vivo confirmed that the formulations were safe and did not elicit any adverse reaction. Additionally, pulmonary delivery of cationic particles in mice resulted in two-fold higher uptake in resident alveolar macrophages compared to non-modified particles. This study provides a framework for future design of drug carriers to improve delivery of anti-TB drugs inside Mtb-infected cells.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Animais , Antituberculosos/farmacologia , Macrófagos , Mamíferos , Camundongos , Rifampina/farmacologia , Tuberculose/tratamento farmacológico
18.
Biomater Adv ; 139: 213003, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35882150

RESUMO

Tuberculosis (TB) is one of the most widely prevalent infectious diseases that cause significant mortality. Bacillus Calmette-Guérin (BCG), the current TB vaccine used in clinics, shows variable efficacy and has safety concerns for immunocompromised patients. There is a need to develop new and more effective TB vaccines. Outer membrane vesicles (OMVs) are vesicles released by Mycobacteria that contain several lipids and membrane proteins and act as a good source of antigens to prime immune response. However, the use of OMVs as vaccines has been hampered by their heterogeneous size and low stability. Here we report that mycobacterial OMVs can be stabilized by coating over uniform-sized 50 nm gold nanoparticles. The OMV-coated gold nanoparticles (OMV-AuNP) show enhanced uptake and activation of macrophages and dendritic cells. Proteinase K and TLR inhibitor studies demonstrated that the enhanced activation was attributed to proteins present on OMVs and was mediated primarily by TLR2 and TLR4. Mass spectrometry analysis revealed several potential membrane proteins that were common in both free OMVs and OMV-AuNP. Such strategies may open up new avenues and the utilization of novel antigens for developing TB vaccines.


Assuntos
Membrana Externa Bacteriana , Proteínas de Membrana , Nanopartículas Metálicas , Mycobacterium tuberculosis , Vacinas , Membrana Externa Bacteriana/imunologia , Vesículas Revestidas/imunologia , Ouro , Humanos , Imunidade , Imunomodulação
19.
Arab J Gastroenterol ; 22(2): 111-114, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34120850

RESUMO

BACKGROUND AND STUDY AIMS: Endoscopic sphincterotomy combined with endoscopic papillary balloon dilatation, mechanical lithotripsy or both, are effective modalities for the ex- traction of difficult common bile duct (CBD) stones. However, approximately 5-15% of cases are still difficult to treat. In the present study, we have evaluated the safety and efficacy of single- operator cholangioscopy guided laser lithotripsy (LL) for difficult to treat CBD stones. PATIENTS AND METHODS: Consecutive patients undergoing LL for the extraction of difficult CBD stones were enrolled in the study. The primary outcomes were related to the efficacy of the procedure in terms of ductal clearance and safety in terms of complications. RESULTS: During the 36 months, 764 patients presented for biliary stone extraction. Most of the patients, 683 (89.4%), had a successful stone extraction with standard techniques. Thirteen patients (1.7%) were not suitable for endoscopic therapy or did not consent for endoscopic therapy, and were referred directly for surgical treatment. Sixty-seven patients (8.8%) were included in the study. Cholangioscope was able to reach the stone in all the cases but one. Complete ductal clearance was achieved in 61 (91%) patients. Complications were encountered in 8 (11.9%) patients. All patients were asymptomatic at one-month of follow-up. CONCLUSION: LL is a highly effective and safe procedure with minimal and transient complications.


Assuntos
Cálculos Biliares , Litotripsia a Laser , Colangiopancreatografia Retrógrada Endoscópica , Cálculos Biliares/cirurgia , Humanos , Índia , Estudos Prospectivos , Esfinterotomia Endoscópica , Centros de Atenção Terciária , Resultado do Tratamento
20.
Front Microbiol ; 11: 583661, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33381088

RESUMO

Antibiotic resistance continues to be a major global health risk with an increase in multi-drug resistant infections seen across nearly all bacterial diseases. Mycobacterial infections such as Tuberculosis (TB) and Non-Tuberculosis infections have seen a significant increase in the incidence of multi-drug resistant and extensively drug-resistant infections. With this increase in drug-resistant Mycobacteria, mycobacteriophage therapy offers a promising alternative. However, a comprehensive study on the infection dynamics of mycobacteriophage against their host bacteria and the evolution of bacteriophage (phage) resistance in the bacteria remains elusive. We aim to study the infection dynamics of a phage cocktail against Mycobacteria under various pathophysiological conditions such as low pH, low growth rate and hypoxia. We show that mycobacteriophages are effective against M. smegmatis under various conditions and the phage cocktail prevents emergence of resistance for long durations. Although the phages are able to amplify after infection, the initial multiplicity of infection plays an important role in reducing the bacterial growth and prolonging efficacy. Mycobacteriophages are effective against antibiotic-resistant strains of Mycobacterium and show synergy with antibiotics such as rifampicin and isoniazid. Finally, we also show that mycobacteriophages are efficient against M. tuberculosis both under lag and log phase for several weeks. These findings have important implications for developing phage therapy for Mycobacterium.

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