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The morphology of fibroblast-like synoviocytes (FLS) issued from the synovial fluid (SF) of patients suffering from osteoarthritis (OA), rheumatoid arthritis (RA), or from healthy subjects (H), as well as the ultrastructure and mechanical properties of the FLS-secreted extracellular vesicles (EV), were analyzed by confocal microscopy, transmission electron microscopy, atomic force microscopy, and tribological tests. EV released under healthy conditions were constituted of several lipid bilayers surrounding a viscous inner core. This "gel-in" vesicular structure ensured high mechanical resistance of single vesicles and good tribological properties of the lubricant. RA, and to a lesser extent OA, synovial vesicles had altered morphology, corresponding to a "gel-out" situation with vesicles surrounded by a viscous gel, poor mechanical resistance, and poor lubricating qualities. When subjected to inflammatory conditions, healthy cells developed phenotypes similar to that of RA samples, which reinforces the importance of inflammatory processes in the loss of lubricating properties of SF.
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Artrite Reumatoide , Vesículas Extracelulares , Osteoartrite , Sinoviócitos , Humanos , Sinoviócitos/fisiologia , Membrana Sinovial , Células Cultivadas , FibroblastosRESUMO
OBJECTIVE: Pickering emulsions are increasingly used in the pharmaceutical and cosmetic fields, especially for topical applications, since these systems require solid particles as emulsifiers instead of surfactants which are known to cause skin irritation. The solid inorganic nanoparticles (TiO2 and ZnO) used as UV filters in sunscreen formulations may also stabilize emulsion droplets, so that the utility of surfactants may be questioned. Surfactant-free sunscreen emulsions solely stabilized by such nanoparticles (NPs) have been studied. METHODS: The ability of these NPs to stabilize o/w emulsions containing a 'model' oil phase, the C12 -C15 alkylbenzoate, has been assessed. ZnO and hydrophilic silica-coated TiO2 NPs widely used in sunscreen products were used together with their mixtures. The emulsification efficiency, the control of droplet size and the stability of o/w Pickering emulsions solely stabilized by NPs were investigated. A ZnO/TiO2 NPs mixture characterized by a theoretical SPF of 45 was finally used as unique emulsifiers to develop a surfactant-free sunscreen emulsion. RESULTS: Stable Pickering emulsions containing 10 up to 60 wt% of C12 -C15 alkyl benzoate were formulated with 2 wt% ZnO in the aqueous phase. The droplet size was controlled by the solid NPs content with respect to oil and the emulsification process. Hydrophilic TiO2 NPs did not allow the stabilization of emulsions. The substitution of TiO2 for ZnO up to 60-70 wt% in a 20/80 o/w emulsion was successfully performed. Finally, a ZnO/TiO2 NP mixture was tested as unique emulsifier system for the formulation of a sunscreen cream. Despite a lower viscosity, the obtained Pickering emulsion was stable and exhibited a photoprotective effect similar to the corresponding surfactant-based sunscreen cream with an in vitro SPF of about 45. CONCLUSION: Surfactant-free Pickering emulsions can be stabilized by the UV-filter nanoparticles for the manufacture of sunscreen products.
OBJECTIFS: Les émulsions de Pickering sont de plus en plus utilisées dans les domaines pharmaceutique et cosmétique, notamment pour les applications topiques, car ces systèmes utilisent des particules solides comme émulsifiants au lieu de tensioactifs qui sont connus pour provoquer des irritations cutanées. Les nanoparticules inorganiques solides (TiO2 et ZnO) utilisées comme filtres UV dans les formulations d'écran solaire peuvent également stabiliser les gouttelettes d'émulsion, de sorte que l'utilité des tensioactifs peut être remise en question. Des émulsions de protection solaire sans tensioactifs et uniquement stabilisées par de telles nanoparticules (NP) ont été étudiées. MÉTHODES: La capacité de ces NP à stabiliser les émulsions H/E contenant une phase huileuse «modèle¼, le benzoate d'alkyle C12 -C15 , a été évaluée. Des NP de ZnO et de TiO2 couvert de silice hydrophile, que l'on trouve largement dans les produits de protection solaire, ont été utilisées séparément et en mélange. L'efficacité d'émulsification, le contrôle de la taille des gouttelettes et la stabilité des émulsions de Pickering H/E uniquement stabilisées par les NP ont été étudiés. Un mélange de NP ZnO/TiO2 caractérisé par un SPF théorique de 45 a finalement été utilisé comme émulsifiant unique pour développer une émulsion de protection solaire sans tensioactif. RÉSULTATS: Des émulsions de Pickering stables contenant 10 à 60% en poids de benzoate d'alkyle C12 -C15 ont été formulées avec 2% en poids de ZnO dans la phase aqueuse. La taille des gouttelettes était contrôlée par la teneur en NP solides par rapport à l'huile et le procédé d'émulsification. Les NP de TiO2 hydrophile n'ont pas permis la stabilisation des émulsions. La substitution des NP de TiO2 par du ZnO jusqu'à 60-70% en poids dans une émulsion 20/80 H/E a été réalisée avec succès. Enfin, un mélange de NP ZnO/TiO2 a été testé en tant que système émulsifiant unique pour la formulation d'une crème solaire. Malgré une viscosité plus faible, l'émulsion de Pickering obtenue était stable et présentait un effet photoprotecteur similaire à la crème solaire à base de tensioactif correspondante avec un SPF in vitro d'environ 45. CONCLUSION: Les émulsions Pickering sans tensioactifs peuvent être stabilisées par les nanoparticules de filtre UV pour la formulation de produits de protection solaire.
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Emulsões , Creme para a Pele/química , Protetores Solares/química , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Tensoativos/química , Titânio/química , Óxido de Zinco/químicaRESUMO
BACKGROUND: Insufficient elastin synthesis leads to vascular complications and arterial hypertension in children with Williams-Beuren syndrome. Restoring sufficient quantity of elastin should then result in prevention or inhibition of vascular malformations and improvement in arterial blood pressure. METHODS: The aim of this study was to assess the efficacy and safety of minoxidil on Intima Media Thickness (IMT) on the right common carotid artery after twelve-month treatment in patient with Williams-Beuren syndrome. We performed a randomized placebo controlled double blind trial. All participants were treated for 12 months and followed for 18 months. The principal outcome was assessed by an independent adjudication committee blinded to the allocated treatment groups. RESULTS: The principal outcome was available for 9 patients in the placebo group and 8 patients in the minoxidil group. After 12-month treatment, the IMT in the minoxidil group increased by 0.03 mm (95% CI -0.002, 0.06) compared with 0.01 mm (95%CI - 0.02, 0.04 mm) in the placebo group (p = 0.4). Two serious adverse events unrelated to the treatment occurred, one in the minoxidil and 1 in the placebo group. After 18 months, the IMT increased by 0.07 mm (95% CI 0.04, 0.10 mm) in the minoxidil compared with 0.01 mm (95% CI -0.02, 0.04 mm) in the placebo group (p = 0.008). CONCLUSION: Our results suggest a slight increase after 12 and 18-month follow-up in IMT. More understanding of the biological changes induced by minoxidil should better explain its potential role on elastogenesis in Williams-Beuren syndrome. TRIALS REGISTRATION: US National Institutes of Health Clinical Trial Register (NCT00876200). Registered 3 April 2009 (retrospectively registered).
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Artéria Carótida Primitiva/patologia , Minoxidil/uso terapêutico , Vasodilatadores/uso terapêutico , Síndrome de Williams/tratamento farmacológico , Adolescente , Artéria Carótida Primitiva/efeitos dos fármacos , Espessura Intima-Media Carotídea , Criança , Método Duplo-Cego , Elastina/metabolismo , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertrofia/tratamento farmacológico , Hipertrofia/etiologia , Masculino , Minoxidil/efeitos adversos , Placebos/uso terapêutico , Vasodilatadores/efeitos adversos , Síndrome de Williams/complicaçõesRESUMO
Industrial accidents, wars and terrorist threats are potential sources of skin contamination by highly toxic chemical warfare agents and manufacturing compounds. We have compared the time-dependent adsorption capacity and decontamination efficiency of fuller's earth (FE) for four different formulations for the molecular tracer, 4-cyanophenol (4-CP), in vitro and ex vivo using water decontamination as standard. The adsorption capacity of FE was assessed in vitro for 4-CP aqueous solutions whereas decontamination efficiency was investigated ex vivo by tracking porcine skin 4-CP content using attenuated total reflectance Fourier transform infrared spectroscopy. Decontamination was performed on short time, exposed porcine skin to 4-CP by application of FE: (1) as free powder; (2) loaded on adhesive tape; (3) on powdered glove; or (4) in suspension. Removal rate of 4-CP from aqueous solutions correlates with the amount of FE and its contact time. Decontamination efficiency estimated by the percentage of 4-CP recovery from contaminated porcine skin, achieved 54% with water, ranged between ~60 and 70% with dry FE and reached ~90% with FE suspension. Successful decontamination of the FE suspension, enabling a dramatic reduction of skin contamination after a brief exposure scenario, appears to be rapid, reliable and should be formulated in a new device ready to use for self-application.
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Compostos de Alumínio/farmacologia , Substâncias para a Guerra Química/toxicidade , Descontaminação/métodos , Compostos de Magnésio/farmacologia , Fenóis/toxicidade , Silicatos/farmacologia , Absorção Cutânea/efeitos dos fármacos , Pele/efeitos dos fármacos , Compostos de Alumínio/química , Animais , Substâncias para a Guerra Química/farmacocinética , Composição de Medicamentos , Técnicas In Vitro , Compostos de Magnésio/química , Fenóis/farmacocinética , Silicatos/química , Pele/metabolismo , SuínosRESUMO
Several excipients are commonly used to enhance the drug absorption through simple epithelia of the digestive tract. They permeate the paracellular barrier constituted by tight junctions (TJs). We compared the effects of two excipients, sodium caprate (C10) and a self-emulsifying excipient Labrasol composed of a mixture of caprylocaproyl polyoxyl-8 glycerides, both applied to emerged reconstructed human epidermis either 'systemically', that is by addition to the culture medium, or topically. During the 'systemic' application, which produced cytoplasmic translocation of occludin and leakage of the biotin marker into the lower stratum corneum, the decrease in the trans-epithelial electrical resistance (TEER) was less abrupt with Labrasol when compared with C10, even though both excipients produced comparable final effects over time. With topical Labrasol, a significant TEER decrease was obtained with 5 times the 'systemic' concentrations. Topical application of C10 also resulted in the loss of the barrier function measured with TEER but had dramatic deleterious effects on the tissue morphology observed with light and electron microscopy. Our study demonstrates the potential value of Labrasol as an enhancer of bioavailability of molecules applied through the transcutaneous route. Our results suggest modulation of the epidermal TJs by both compounds. Even though the C10 action was at least partly due to overall cell damage and despite the fact that the decrease in TEER after topical application was apparently related to the permeabilization of the primary barrier of the stratum corneum in the first place.
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Ácidos Decanoicos/farmacologia , Epiderme/efeitos dos fármacos , Epiderme/fisiologia , Excipientes/farmacologia , Glicerídeos/farmacologia , Administração Cutânea , Biotina/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Impedância Elétrica , Epiderme/ultraestrutura , Humanos , Queratinócitos , Ocludina/metabolismo , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Junções Íntimas/efeitos dos fármacos , Técnicas de Cultura de TecidosRESUMO
INTRODUCTION: The COVID-19 pandemic has led to unforeseen and novel manifestations, as illustrated by the management of drug shortages through the development of hospital production of sterile pharmaceutical preparations (P2S). Visual inspection of P2S is a release control whose methods are described in monographs of the European Pharmacopoeia (2.9.20) and the United States Pharmacopeia (1790). However, these non-automated visual methods require training and proficiency testing of personnel. The main objective of this work was to compare the reliability and speed of analysis of two visual methods and an automated method for detecting visible particles by image analysis in P2S. Furthermore, these methods were used to evaluate sources of particulate contamination during pre-production processes (washing, disinfection, depyrogenation) and production (filling, capping). MATERIALS AND METHODS: Three pharmacy technicians examined 41 clear glass vials of type I, 10 and/or 50 mL through manual visual inspection (MVI), semi-automated (SAVI), and automated (AVI) inspection. The vials were distributed as follows: (i) 16 vials of water for injection containing either glass particles (224 µm or 600 µm), stopper fragments, or textile fibres; (ii) five sterile injectable specialties; (iii) 20 vials of water for injection prepared under different pre-production conditions. RESULTS AND DISCUSSION: MVI and SAVI detected 100% of visible particles compared with 28% for AVI, which showed a deficiency in detecting textile fibres. All three methods correctly analysed P2S that did not contain visible particles. The three methods detected particles in vials maintained under International Organization for Standardization (ISO) 9 pre-production conditions. However, detections by (i) MVI and SAVI, and by (ii) AVI of particles contained in vials maintained under ISO 8 pre-production conditions were deemed satisfactory and unsatisfactory, respectively. CONCLUSION: The importance of visual inspection of P2S requires rapid, sensitive, and reliable detection methods. In this context, MVI and SAVI have proven to be more effective than AVI for a more competitive financial, training, and implementation investment.
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INTRODUCTION: Intermediate-risk (IR) Non-Muscle Invasive Bladder Cancer (NMIBC) is associated with a high rate of tumor recurrence. To improve patient outcomes, it is recommended to use adjuvant intravesical therapy, by mitomycin C (MMC) or Bacillus Calmette Guerin (BCG). Gemcitabine (GMC) is a known molecule used in urothelial cancer. We aimed to study the efficacy and safety profile of a gemcitabine solution, compared to mitomycin C, in the treatment of IR NMIBC. MATERIAL: In this retrospective study, patients with IR NMIBC treated between 2016 and 2020 were selected from two participating centers using either gemcitabine (center A) as the intravesical chemotherapy regimen or mitomycin C (center B). The primary endpoint was recurrence rate and secondary end points were treatment interruption and its causes. RESULTS: In our cohort of 102 IR NMIBC patients, 49 patients received GMC and 53 MMC with a median follow-up of 30 months. Overall recurrence rate was 42.1% with 22.4% in the GMC group and 60.3% in the MMC group (P<0.01). This difference was also found in the multifactorial analysis. Course interruption was observed in 14.7% of all patients, primarily attributed to adverse events (46.6%), without difference between groups. CONCLUSION: Adjuvant intravesical gemcitabine in patients with IR NMIBC seems to be an interesting option associated with a lower tumor recurrence rate and a favorable tolerance profile when compared to MMC. Larger scale prospective randomized trials are needed to validate our findings. LEVEL OF EVIDENCE: III.
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Chemotherapy products in hospitals include a reconstitution step of manufactured drugs providing an adapted dosage to each patient. The administration of highly iatrogenic drugs raises the question of patients' safety and treatment efficiency. In order to reduce administration errors due to faulty preparations, we introduced a new qualitative and quantitative routine control based on Fourier Transform Infrared (FTIR) and UV-Visible spectrophotometry. This automated method enabled fast and specific control for 14 anticancer drugs. A 1.2 mL sample was used to assay and identify each preparation in less than 90 sec. Over a two-year period, 9370 controlled infusion bags showed a 1.49% nonconformity rate, under 15% tolerance from the theoretical concentration and 96% minimum identification matching factor. This study evaluated the reliability of the control process, as well as its accordance to chemotherapy deliverance requirements. Thus, corrective measures were defined to improve the control process.
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Antineoplásicos/análise , Composição de Medicamentos/métodos , Erros de Medicação/prevenção & controle , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Humanos , Controle de Qualidade , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta/métodos , Fatores de TempoRESUMO
Rheumatoid synovitis is infiltrated by immune cells that interact with synoviocytes, leading to the pannus formation. Inflammation or cell interaction effects are mainly evaluated with cytokine production, cell proliferation or migration. Few studies interest on cell morphology. Here, the purpose was to deepen some morphological changes of synoviocytes or immune cells under inflammatory conditions. Inflammatory cytokines, IL-17 and TNF that are largely involved in RA pathogenesis, induced a change in synoviocyte morphology, inducing a retracted cell with higher number of pseudopodia. Several morphological parameters decreased in inflammatory conditions: cell confluence, area and motility speed. The same impact on cell morphology was observed in co-culture of synoviocytes and immune cells in inflammatory/non-inflammatory conditions or with cell activation (miming the in vivo situation), affecting both cell types: synoviocytes were retracted and inversely immune cells proliferated, indicating that cell activation induced a morphological change of cells. In contrast, with RA but not control synoviocytes, cell interactions were not sufficient to affect PBMC and synoviocyte morphology. The morphological effect came only from the inflammatory environment. These findings reveal that the inflammatory environment or cell interactions induced massive changes in control synoviocytes, with cell retraction and increase of pseudopodia number, leading to better interactions with other cells. Except in the case of RA, the inflammatory environment was absolutely required for such changes.
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Artrite Reumatoide , Sinoviócitos , Humanos , Sinoviócitos/patologia , Citocinas/farmacologia , Leucócitos Mononucleares/patologia , Artrite Reumatoide/patologia , Proliferação de Células , Células Cultivadas , Citoesqueleto , Fibroblastos/patologia , Comunicação CelularRESUMO
During the early months of the COVID-19 pandemic, the international medical product supply chain was tight, causing breaks in the availability of neuromuscular blocking agents essential for the treatment of patients in intensive care units. The present study describes the pharmaceutical development of an injectable 2 mg/mL solution of pancuronium bromide (PC) in a very short lapse of time. The sterile solution was compounded into a good manufacturing practice grade A clean room, filtered (0.2 µm) and filled into 10 mL type I glass, manually sealed with bromobutyl rubber stoppers. A novel HPLC-MS stability indicating method for pancuronium quantification and its degradation product was developed and validated. This fast, sensitive and straightforward method was used to study the stability of the formulation using a semi-predictive method, enabling a very fast attribution of a temporary shelf-life, which was confirmed by a classic prospective stability study. The production line and the analytical tools set-up were performed in six weeks and the semi-predictive stability study was conducted in 90 days, allowing us to predict a shelf life, which was successfully confirmed by prospective study. In conclusion, using innovative methods, we were able to rapidly overcome the shortage of a critical drug.
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COVID-19 , Pancurônio , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Estudos Prospectivos , Pandemias , Estabilidade de Medicamentos , Composição de MedicamentosRESUMO
Ions play a crucial role in skin homeostasis. Calcium, a participant in wound healing and keratinization, is localized at an increasing gradient from the stratum basal to the stratum granulosum. In vivo and in vitro studies show disturbances in this gradient in damaged skin. We developed here a model to study ex vivo calcium outward flux from normal and tape-stripped human skin. We measured here, with a calcium specific electrode, ex vivo calcium percutaneous eggression from dermis to epidermis in normal and tape-stripped skin places in franz cells, with a calcium source or not in the dermis compartment. Tape-stripped skin released a greater calcium concentration and had a higher rate over time than normal skin in both cases. The rate went from 8.1.10(-3) ± 8.9.10(-3) nmol.cm(-2).min(-1) to 4.8.10(-2) ± 1.8.10(-2) nmol.cm(-2).min(-1) with no calcium in the dermis compartment and from 1.7.10(-1) ± 1.2.10(-1) nmol.cm(-2).min(-1) to 5.9 ± 3.4 nmol.cm(-2).min(-1) with calcium. Also calcium uptake from the dermis is greater in tape-stripped skin during the first 5 h of the experiment. This ex vivo method reproduced the increased of calcium skin permeability with a disrupted barrier. This approach aims to develop a non-invasive method to measure calcium flux concentration in normal and damaged skin that might be reproduced and validated in vivo.
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Cálcio/metabolismo , Derme/metabolismo , Epiderme/metabolismo , Pele/lesões , Humanos , Técnicas In VitroRESUMO
The widespread use of indwelling medical devices has enormously increased the interest in materials incorporating antibiotics and antimicrobial agents as a means to prevent dangerous device-related infections. Recently, chlorhexidine-loaded polyurethane has been proposed as a material suitable for the production of devices which are able to resist microbial contamination. The aim of the present study was to characterize the in vitro release of chlorhexidine from new polymeric orthodontic chains realized with polyurethane loaded with two different chlorhexidine salts: chlorhexidine diacetate or chlorhexidine digluconate. The orthodontic chains constituted of three layers: a middle polyurethane layer loaded with chlorhexidine salt inserted between two layers of unloaded polymer. In vitro release of chlorhexidine diacetate and digluconate from orthodontic chains loaded with 10% or 20% (w/w) chlorhexidine salt was sustained for 42 days and followed Fickian diffusion. The drug diffusion through the polyurethane was found to be dependent not only on chlorhexidine loading, but also on the type of chlorhexidine salt. The antibacterial activity of 0.2% (w/w) chlorhexidine diacetate-loaded orthodontic chain was successfully tested towards clinically isolated biofilm forming ica-positive Staphylococcus epidermidis via agar diffusion test. In conclusion, the chlorhexidine salt-loaded chains could provide an innovative approach in the prevention of oral infections related to the use of orthodontic devices.
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Antibacterianos/química , Antibacterianos/farmacologia , Clorexidina/análogos & derivados , Clorexidina/química , Clorexidina/farmacologia , Poliuretanos/química , Antibacterianos/administração & dosagem , Biofilmes/efeitos dos fármacos , Clorexidina/administração & dosagem , Humanos , Cinética , Polímeros/química , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/isolamento & purificação , Staphylococcus epidermidis/fisiologiaRESUMO
Bacteriophages are naturally occurring viruses that specifically target bacteria. They are widely distributed in the environment. The concept of phage therapy is to isolate phages, characterize them, cultivate them and then purify them to treat bacterial infections. There is currently a revival of phage therapy, and its implementation presupposes the availability of active phages of pharmaceutical quality. From a regulatory point of view, the status of phages is not yet clearly defined by the authorities. The availability of phages produced by the pharmaceutical industry and through academic development programs such as the PHAGEinLYON program represents a breakthrough in the development of phage therapy. Prosthetic joint infections and digestive diseases seem to be relevant indications, but preclinical studies and randomized clinical trials are now needed to be done.
Title: Les virus au service de la santé : les bactériophages. Abstract: Les bactériophages sont des virus naturels très répandus dans l'environnement qui ciblent spécifiquement les bactéries. Leur utilisation en médecine, connue sous le terme phagothérapie, consiste à les isoler, les caractériser, les cultiver, puis les purifier pour traiter des infections bactériennes. Il existe actuellement un renouveau pour la thérapie phagique, et sa mise en Åuvre présuppose de disposer de phages actifs de qualité pharmaceutique. D'un point de vue réglementaire, le statut des phages n'est pas encore clairement défini par les autorités, mais la mise à disposition de phages produits par l'industrie pharmaceutique et les programmes de développement académiques, comme le programme PHAGEinLYON, constituent un tournant dans le déploiement de la phagothérapie.
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Infecções Bacterianas , Bacteriófagos , Terapia por Fagos , Humanos , Bactérias , Infecções Bacterianas/terapiaRESUMO
Bacterial resistance against antibiotics is an emergent medical issue. The development of novel therapeutic approaches is urgently needed and, in this context, bacteriophages represent a promising strategy to fight multi resistant bacteria. However, for some applications, bacteriophages cannot be used without an appropriate drug delivery system which increases their stability or provides an adequate targeting to the site of infection. This review summarizes the main application routes for bacteriophages and presents the new delivery approaches designed to increase phage's activity. Clinical successes of these formulations are also highlighted. Globally, this work paves the way for the design and optimization of nano and micro delivery systems for phage therapy.
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Infecções Bacterianas , Bacteriófagos , Terapia por Fagos , Antibacterianos/uso terapêutico , Bactérias , Infecções Bacterianas/tratamento farmacológico , Sistemas de Liberação de Medicamentos , HumanosRESUMO
Background: Phage therapy a promising antimicrobial strategy to address antimicrobial resistance for infections caused by the major human pathogen Staphylococcus aureus. Development of therapeutic phages for human use should follow pharmaceutical standards, including selection of strictly lytic bacteriophages with high therapeutic potential and optimization of their production process. Results: Here, we describe three novel Silviavirus phages active against 82% of a large collection of strains (n = 150) representative of various methicillin-susceptible and -resistant S. aureus clones circulating worldwide. We also investigated the optimization of the efficiency and safety of phage amplification protocols. To do so, we selected a well-characterized bacterial strain in order to (i) maximize phage production yields, reaching phage titres of 1011 PFU/mL in only 4 h; and (ii) facilitate phage purity while minimizing the risk of the presence of contaminants originating from the bacterial host; i.e., secreted virulence factors or induced temperate phages. Conclusions: In sum, we propose a quality-by-design approach for the amplification of broad-spectrum anti-S. aureus phages, facilitating the subsequent steps of the manufacturing process; namely, purification and quality control.
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Several tight junction (TJ) proteins were detected in the living layers of adult human epidermis, and TJ-like membrane ridges were observed at the top of the stratum granulosum (SG) in freeze-fracture studies. We applied standard and immunoelectron microscopy to look for TJ-derived structures in the stratum corneum (SC) of human adult epidermis and in cornified envelopes purified from the plantar SC. Besides confirming claudin-1 labelling in the proximity of SG desmosomes, we also observed immunolocalization near corneodesmosomes in the lower SC. In addition, TJ proteins were consistently detected in the purified cornified envelopes. Lateral but not horizontal walls of the corneocytes showed frequent points of molecular fusion between lipid envelopes. These structural associations were very frequently localized at the top of the lateral corneocyte membranes, thus sealing the extremities of lateral intercorneocyte spaces. We propose that TJ-like structures persist in the SC and contribute to the reinforcement of lateral contacts and to the formation of membrane interdigitations between corneocytes. Their presence could contribute to subdivision of the extracellular spaces of SC into consecutive individualized compartments. Intercellular lipids, enzymes and other (glyco)protein content could thus evolve in the keratinized epidermal layer at different paces, as preprogrammed in the underlying living cells and influenced by the environment, e.g. humidity. Such situation might explain differences in the degradation rates between the 'peripheral' and the 'non-peripheral' corneodesmosomes observed during physiological desquamation, as previously suggested by us and others.
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Células Epidérmicas , Epiderme/ultraestrutura , Junções Íntimas/ultraestrutura , Claudina-1 , Desmossomos/ultraestrutura , Epiderme/metabolismo , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/ultraestrutura , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/ultraestrutura , Microscopia Imunoeletrônica , Ocludina , Junções Íntimas/metabolismoRESUMO
Often presented as metabolism byproducts, reactive oxygen species are linked to detrimental effects such as chronic wound, mutagenesis, cancer and skin ageing. However, recent in vitro and in vivo observations suggest that ROS, and mainly hydrogen peroxide, interfere with cell signaling acting like second messenger and inducing adaptive responses. This is particularly observed in skin wound healing where cells are exposed to H2O2 following injury. In this study, we developed and characterized an innovative formulation producing H2O2 at low concentrations, in order to mimic physiological inflammation phase. Then, this pro-oxidative formulation (CAM-GOx) was assayed in vitro on keratinocytes cell culture, compared to the blank formulation (CAM) and the anti-oxidative formulation (CAM-CAT) to assess whether oxidative stress was implied or not in cellular responses.
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Estresse Oxidativo/fisiologia , Cicatrização/fisiologia , Alginatos , Ensaios de Migração Celular , Células Cultivadas , Quitosana , Humanos , Peróxido de Hidrogênio/metabolismo , Queratinócitos/citologia , Microesferas , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Phage-derived therapies comprise phage therapy and the use of phage-derived proteins as anti-bacterial therapy. Bacteriophages are natural viruses that target specific bacteria. They were proposed to be used to treat bacterial infections in the 1920s, before the discovery and widespread over-commercialized use of antibiotics. Phage therapy was totally abandoned in Western countries, whereas it is still used in Poland, Georgia and Russia. We review here the history of phage therapy by focusing on bone and joint infection, and on the development of phage therapy in France in this indication. We discuss the rationale of its use in bacterial infection and show the feasibility of phage therapy in the 2020s, based on several patients with complex bone and joint infection who recently received phages as compassionate therapy. Although the status of phage therapy remains to be clarified by health care authorities, obtaining pharmaceutical-grade therapeutic phages (i.e., following good manufacturing practice guidelines or being "GMP-like") targeting bacterial species of concern is essential. Moreover, multidisciplinary clinical expertise has to determine what could be the relevant indications to perform clinical trials. Finally "phage therapy 2.0" has to integrate the following steps: (i) follow the status of phage therapy, that is not settled and defined; (ii) develop in each country a close relationship with the national health care authority; (iii) develop industrial-academic partnerships; (iv) create academic reference centers; (v) identify relevant clinical indications; (vi) use GMP/GMP-like phages with guaranteed quality bioproduction; (vii) start as salvage therapy; (vii) combine with antibiotics and adequate surgery; and (viii) perform clinical trials, to finally (ix) demonstrate in which clinical settings phage therapy provides benefit. Phage-derived proteins such as peptidoglycan hydrolases, polysaccharide depolymerases or lysins are enzymes that also have anti-biofilm activity. In contrast to phages, their development has to follow the classical process of medicinal products. Phage therapy and phage-derived products also have a huge potential to treat biofilm-associated bacterial diseases, and this is of crucial importance in the worldwide spread of antimicrobial resistance.