Treatment For Infected Frozen Elephant Trunk Prosthesis Caused by Propionibacterium acnes: A Surgical Challenge

ABSTRACT In this article, we present the case of a 47-year-old man who underwent Bentall-Bono procedure and frozen elephant trunk prosthesis implantation due to severe aortic regurgitation and aortic dilatation with a second-time endovascular stent-graft repair in descending aorta. Over eight years, a subacute graft infection by Propionibacterium acnes was developed, culminating in cardiogenic shock secondary to severe aortic regurgitation due to a complete aortic root dehiscence because of multiple aortic pseudoaneurysms. The patient underwent emergency surgery in which the replacement of the graft by a biological valve tube was performed accompanied by a complete debranching of the three supra-aortic vessels.

Treatment For Infected Frozen Elephant Trunk Prosthesis Caused by Propionibacterium acnes: A Surgical Challenge.

In this article, we present the case of a 47-year-old man who underwent Bentall-Bono procedure and frozen elephant trunk prosthesis implantation due to severe aortic regurgitation and aortic dilatation with a second-time endovascular stent-graft repair in descending aorta. Over eight years, a subacute graft infection by Propionibacterium acnes was developed, culminating in cardiogenic shock secondary to severe aortic regurgitation due to a complete aortic root dehiscence because of multiple aortic pseudoaneurysms. The patient underwent emergency surgery in which the replacement of the graft by a biological valve tube was performed accompanied by a complete debranching of the three supra-aortic vessels.

The immunomodulatory potential of phage therapy to treat acne: a review on bacterial lysis and immunomodulation.

Background: Characterized by an inflammatory pathogenesis, acne is the most common skin disorder worldwide. Altered sebum production, abnormal proliferation of keratinocytes, and microbiota dysbiosis represented by disbalance in Cutibacterium acnes population structure, have a synergic effect on inflammation of acne-compromised skin. Although the role of C. acnes as a single factor in acne development is still under debate, it is known that skin and skin-resident immune cells recognize this bacterium and produce inflammatory markers as a result. Control of the inflammatory response is frequently the target for acne treatment, using diverse chemical or physical agents including antibiotics. However, some of these treatments have side effects that compromise patient adherence and drug safety and in the case of antibiotics, it has been reported C. acnes resistance to these molecules. Phage therapy is an alternative to treat antibiotic-resistant bacterial strains and have been recently proposed as an immunomodulatory therapy. Here, we explore this perspective about phage therapy for acne, considering the potential immunomodulatory role of phages. Methodology: Literature review was performed using four different databases (Europe PubMed Central-ePMC, Google Scholar, PubMed, and ScienceDirect). Articles were ordered and selected according to their year of publication, number of citations, and quartile of the publishing journal. Results: The use of lytic bacteriophages to control bacterial infections has proven its promising results, and anti-inflammatory effects have been found for some bacteriophages and phage therapy. These effects can be related to bacterial elimination or direct interaction with immune cells that result in the regulation of pro-inflammatory cytokines. Studies on C. acnes bacteriophages have investigated their lytic activity, genomic structure, and stability on different matrices. However, studies exploring the potential of immunomodulation of these bacteriophages are still scarce. Conclusions: C. acnes bacteriophages, as well as other phages, may have direct immunomodulatory effects that are yet to be fully elucidated. To our knowledge, to the date that this review was written, there are only two studies that investigate anti-inflammatory properties for C. acnes bacteriophages. In those studies, it has been evidenced reduction of pro-inflammatory response to C. acnes inoculation in mice after bacteriophage application. Nevertheless, these studies were conducted in mice, and the interaction with the immune response was not described. Phage therapy to treat acne can be a suitable therapeutic alternative to C. acnes control, which in turn can aid to restore the skin's balance of microbiota. By controlling C. acnes colonization, C. acnes bacteriophages can reduce inflammatory reactions triggered by this bacterium.

SlpB Protein Enhances the Probiotic Potential of L. lactis NCDO 2118 in Colitis Mice Model.

Bacteria used in the production of fermented food products have been investigated for their potential role as modulators of inflammation in gastrointestinal tract disorders such as inflammatory bowel diseases (IBD) that cause irreversible changes in the structure and function of gut tissues. Ulcerative colitis (UC) is the most prevalent IBD in the population of Western countries, and it is marked by symptoms such as weight loss, rectal bleeding, diarrhea, shortening of the colon, and destruction of the epithelial layer. The strain Propionibacterium freudenreichii CIRM-BIA 129 recently revealed promising immunomodulatory properties that greatly rely on surface-layer proteins (Slp), notably SlpB. We, thus, cloned the sequence encoding the SlpB protein into the pXIES-SEC expression and secretion vector, and expressed the propionibacterial protein in the lactic acid bacterium Lactococcus lactis NCDO 2118. The probiotic potential of L. lactis NCDO 2118 harboring pXIES-SEC:slpB (L. lactis-SlpB) was evaluated in a UC-mice model induced by Dextran Sulfate Sodium (DSS). During colitis induction, mice receiving L. lactis-SlpB exhibited reduced severity of colitis, with lower weight loss, lower disease activity index, limited shortening of the colon length, and reduced histopathological score, with significant differences, compared with the DSS group and the group treated with L. lactis NCDO 2118 wild-type strain. Moreover, L. lactis-SlpB administration increased the expression of genes encoding tight junction proteins zo-1, cln-1, cln-5, ocln, and muc-2 in the colon, increased IL-10 and TGF-ß, and decreased IL-17, TNF-α, and IL-12 cytokines in the colon. Therefore, this work demonstrates that SlpB recombinant protein is able to increase the probiotic potential of the L. lactis strain to alleviate DSS-induced colitis in mice. This opens perspectives for the development of new approaches to enhance the probiotic potential of strains by the addition of SlpB protein.

Improving propionic acid production from a hemicellulosic hydrolysate of sorghum bagasse by means of cell immobilization and sequential batch operation.

Propionic acid (PA) is an important organic compound with extensive application in different industrial sectors and is currently produced by petrochemical processes. The production of PA by large-scale fermentation processes presents a bottleneck, particularly due to low volumetric productivity. In this context, the present work aimed to produce PA by a biochemical route from a hemicellulosic hydrolysate of sorghum bagasse using the strain Propionibacterium acidipropionici CIP 53164. Conditions were optimized to increase volumetric productivity and process efficiency. Initially, in simple batch fermentation, a final concentration of PA of 17.5 g⋅L-1 was obtained. Next, fed batch operation with free cells was adopted to minimize substrate inhibition. Although a higher concentration of PA was achieved (38.0 g⋅L-1 ), the response variables (YP/S = 0.409 g⋅g-1 and QP = 0.198 g⋅L-1 ⋅H-1 ) were close to those of the simple batch experiment. Finally, the fermentability of the hemicellulosic hydrolysate was investigated in a sequential batch with immobilized cells. The PA concentration achieved a maximum of 35.3 g⋅L-1 in the third cycle; moreover, the volumetric productivity was almost sixfold higher (1.17 g⋅L-1 ⋅H-1 ) in sequential batch than in simple batch fermentation. The results are highly promising, providing preliminary data for studies on scaling up the production of this organic acid.

Antimicrobial photodynamic therapy against Propionibacterium acnes biofilms using hypericin (Hypericum perforatum) photosensitizer: in vitro study.

Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial photodynamic therapy (aPDT) has broad therapeutic applicability. The purpose was to evaluate in vitro the photodynamic inactivation against Propionibacterium acnes (P. acnes) biofilms by using different concentrations of hypericin (Hypericum perforatum) photosensitizer associated with different energies of low-level laser. The biofilms were placed in 96-well microplates with a 6.4-mm diameter surface, by using standard suspensions (2 × 107 CFU/mL) and grown in brain heart infusion broth (BHI) for 48 h in anaerobic chamber. Subsequently, the control group received application of 0.9% sterile saline solution for 3 min; the photosensitising groups received hypericin at concentrations of 5 and 15 µg/mL for 3 min; the laser groups received irradiation of energies of 3 and 5 J (660 nm, continuous output, 100 mW, 30 and 50 s and 100 J/cm2 and 166 J/cm2, respectively); the aPDT groups received 5 and 15 µg/mL concentrations of hypericin associated with energies of 3 and 5 J of low-level laser irradiation. After the biofilms were broken up and seeded for CFU counting. The results showed a reduction in P. acnes biofilms after aPDT emphasising that 15 µg/mL hypericin associated with 3 and 5 J laser irradiation reduced biofilms by 14.1 and 27.9%, respectively. In addition, all groups of aPDT demostrated statistically significant reductions. In vitro photodynamic inactivation against P. acnes biofilms using different concentration of hypericin photosensitizer associated with different energies of low-level laser promoted effective antimicrobial action.

Evaluation of tea tree oil physicochemical features and its antimicrobial activity against Cutibacterium acnes (Propionibacterium acnes) ATCC 6919 / [Evaluación de las características fisicoquímicas y de la actividad antimicrobiana del aceite del árbol de té contra Cutibacterium acnes (Propionibacterium acnes) ATCC 6919].

Introduction: Tea tree oil is an essential oil recognized for its antimicrobial properties. Objective: To evaluate the composition, features, and antimicrobial effect at 2% v/v, and its minimal inhibitory concentration (MIC) against Cutibacterium acnes (Propionibacterium acnes). Materials and methods: Three different batches of tea tree oil were evaluated. We characterized its chemotype by gas chromatography and its 2% v/v antimicrobial activity against C. acnes by agar diffusion assay (guide M11-A8 CLSI). Results: The three batches of oil had the chemotypes required by the ISO 4730 standard, which indicates that it is a high-quality product. Additionally, they had 30% to 40% of terpinen-4-ol, a compound that favors its antimicrobial activity. Antimicrobial activity against C. acnes for all batches had a concentration-dependent effect with microbial growth inhibitory activity in all assays at 2% v/v. The MIC obtained against C. acnes for all batches was 0.25% v/v. The antimicrobial activity of tea tree oil against this microorganism has been previously reported with a MIC between 0.05% and 1.25% v/v, a range that covers the one obtained in this study. Conclusion: These results show the high quality of the oil and its capacity as an antibacterial agent against C. acnes. New studies should be conducted to confirm its activity and that of its components in isolates of the microorganism from patients with acne vulgaris.

Introducción. El aceite del árbol de té es un aceite esencial reconocido por sus propiedades antimicrobianas. Objetivos. Evaluar la composición, características y efecto antimicrobiano del aceite al 2 % del árbol de té y su concentración inhibitoria mínima (CIM) contra Cutibacterium acnes (Propionibacterium acnes). Materiales y métodos. Se evaluó el quimiotipo en tres lotes diferentes de este aceite mediante cromatografía de gases, así como su actividad antimicrobiana en concentración al 2 % v/v y la CIM contra C. acnes mediante ensayo de difusión en agar (guía M11-A8 CLSI). Resultados. Los lotes evaluados presentaron los quimiotipos ajustados a la norma ISO 4730, lo que indicó la alta calidad del producto. Los lotes contenían de 30 a 40 % de terpinen-4-ol, compuesto que favorece la actividad antimicrobiana, la cual presentó en todos los lotes un efecto dependiente de la concentración contra C. acnes, con una inhibición del crecimiento microbiano en concentración al 2 % v/v en todas las pruebas. La concentración inhibitoria mínima fue de 0,25 % v/v. La actividad antimicrobiana del aceite del árbol de té contra este microorganismo ya ha sido reportada con una concentración inhibitoria mínima entre 0,05 y 1,25 % v/v, rango que cobija la obtenida en este estudio. Conclusiones. Los resultados evidenciaron la gran calidad de este producto y su capacidad como agente antibacteriano contra C. acnes. Se deben hacer estudios con otros aislamientos del microorganismo provenientes de pacientes con acné vulgar para confirmar su actividad general y la de cada uno de sus componentes.

Evaluación de las características fisicoquímicas y de la actividad antimicrobiana del aceite del árbol de té contra Cutibacterium acnes (Propionibacterium acnes) ATCC 6919 / Evaluation of tea tree oil physicochemical features and its antimicrobial activity against Cutibacterium acnes (Propionibacterium acnes) ATCC 6919

Resumen: Introducción. El aceite del árbol de té es un aceite esencial reconocido por sus propiedades antimicrobianas. Objetivos. Evaluar la composición, características y efecto antimicrobiano del aceite al 2 % del árbol de té y su concentración inhibitoria mínima (CIM) contra Cutibacterium acnes (Propionibacterium acnes). Materiales y métodos. Se evaluó el quimiotipo en tres lotes diferentes de este aceite mediante cromatografía de gases, así como su actividad antimicrobiana en concentración al 2 % v/v y la CIM contra C. acnes mediante ensayo de difusión en agar (guía M11-A8 CLSI). Resultados. Los lotes evaluados presentaron los quimiotipos ajustados a la norma ISO 4730, lo que indicó la alta calidad del producto. Los lotes contenían de 30 a 40 % de terpinen-4-ol, compuesto que favorece la actividad antimicrobiana, la cual presentó en todos los lotes un efecto dependiente de la concentración contra C. acnes, con una inhibición del crecimiento microbiano en concentración al 2 % v/v en todas las pruebas. La concentración inhibitoria mínima fue de 0,25 % v/v. La actividad antimicrobiana del aceite del árbol de té contra este microorganismo ya ha sido reportada con una concentración inhibitoria mínima entre 0,05 y 1,25 % v/v, rango que cobija la obtenida en este estudio. Conclusiones. Los resultados evidenciaron la gran calidad de este producto y su capacidad como agente antibacteriano contra C. acnes. Se deben hacer estudios con otros aislamientos del microorganismo provenientes de pacientes con acné vulgar para confirmar su actividad general y la de cada uno de sus componentes.

Abstract: Introduction: Tea tree oil is an essential oil recognized for its antimicrobial properties. Objective: To evaluate the composition, features, and antimicrobial effect at 2% v/v, and its minimal inhibitory concentration (MIC) against Cutibacterium acnes (Propionibacterium acnes). Materials and methods: Three different batches of tea tree oil were evaluated. We characterized its chemotype by gas chromatography and its 2% v/v antimicrobial activity against C. acnes by agar diffusion assay (guide M11-A8 CLSI). Results: The three batches of oil had the chemotypes required by the ISO 4730 standard, which indicates that it is a high-quality product. Additionally, they had 30% to 40% of terpinen-4-ol, a compound that favors its antimicrobial activity. Antimicrobial activity against C. acnes for all batches had a concentration-dependent effect with microbial growth inhibitory activity in all assays at 2% v/v. The MIC obtained against C. acnes for all batches was 0.25% v/v. The antimicrobial activity of tea tree oil against this microorganism has been previously reported with a MIC between 0.05% and 1.25% v/v, a range that covers the one obtained in this study. Conclusion: These results show the high quality of the oil and its capacity as an antibacterial agent against C. acnes. New studies should be conducted to confirm its activity and that of its components in isolates of the microorganism from patients with acne vulgaris.

Biosynthesis of vitamin B12 by Propionibacterium freudenreichii subsp. shermanii ATCC 13673 using liquid acid protein residue of soybean as culture medium.

Vitamin B12 deficiency still persists, mainly caused by low intake of animal food products affecting vegetarians, vegans, and populations of underdeveloped countries. In this study, we investigate the biosynthesis of vitamin B12 by potential probiotic bacterium using an agroindustry residue, the liquid acid protein residue of soybean (LAPRS), as a low-cost, animal derivate-free alternative culture medium. Cultures of Propionibacterium freudenreichii subsp. shermanii ATCC 13673 growing in LAPRS for vitamin B12 biosynthesis were studied using the Plackett-Burman experimental approach, followed by a central composite design 22 to optimize the concentration of significant variables. We also performed a proteolytic treatment of LAPRS and evaluated the optimized-hydrolyzed medium influence on the microbial growth and metabolism in shaker flask and bioreactor experiments. In this all-plant source medium, P. freudenreichii subsp. shermanii produced high concentrations of cells and high amounts of vitamin B12 (0.6 mg/g cells) after process optimization. These results suggest the possibility of producing vitamin B12 by a potential probiotic bacterium in a very cheap, animal derivate-free medium to address the needs of specific population groups, at the same time reducing the production costs of this essential vitamin.

Protective Cellular Immune Response Induction for Cutaneous Leishmaniasis by a New Immunochemotherapy Schedule.

The palladacycle complex DPPE 1.2 was previously shown to inhibit Leishmania (Leishmania) amazonensis infection in vitro and in vivo. The present study aimed to evaluate the effect of DPPE 1.2 associated with a recombinant cysteine proteinase, rLdccys1, and the adjuvant Propionibacterium acnes on L. (L.) amazonensis infection in two mouse strains, BALB/c, and C57BL/6. Treatment with this association potentiated the leishmanicidal effect of DPPE 1.2 resulting in a reduction of parasite load in both strains of mice which was higher compared to that found in groups treated with either DPPE 1.2 alone or associated with P. acnes or rLdccys1. The reduction of parasite load in both mice strains was followed by immunomodulation mediated by an increase of memory CD4+ and CD8+ T lymphocytes, IFN-γ levels and reduction of active TGF-ß in treated animals. No infection relapse was observed 1 month after the end of treatment in mice which received DPPE 1.2 associated with rLdccys1 or rLdccys1 plus P. acnes in comparison to that exhibited by animals treated with DPPE 1.2 alone. Evaluation of serum levels of AST, ALT, urea, and creatinine showed no alterations among treated groups, indicating that this treatment schedule did not induce hepato or nephrotoxicity. These data indicate the potential use of this association as a therapeutic alternative for cutaneous leishmaniasis caused by L. (L) amazonensis.

Effects of cutting height and bacterial inoculant on corn silage aerobic stability and nutrient digestibility by sheep

In this study, we aimed to determine the effects of cutting height (25 or 40 cm above ground) and bacterial inoculation (a combined inoculant of Lactobacillus plantarum and Propionibacterium acidipropionici) on the chemical and microbial compositions, fermentative profile, and aerobic stability of whole-plant corn silage and nitrogen balance, intake, and apparent nutrient digestibility by sheep. To evaluate silage characteristics and sheep metabolism, we performed analyses based on a completely randomized block design with a 2×2 factorial arrangement (two cutting heights, with or without bacterial inoculant). We evaluated the chemical and microbial compositions, pH, fermentation end-products, and aerobic stability of silage. To examine nutrient digestibility of silage, we used 24 male sheep over a 21-day period. We found that the aerobic stability did not differ among the silages. Sheep fed silages produced from corn harvested at 40 cm had increased intakes of crude protein, non-fiber carbohydrate, and total digestible nutrients, whereas the non-fiber carbohydrate intake of inoculated corn silages was found to be higher than that of uninoculated silage. Furthermore, the amounts of nitrogen retained by sheep fed silage produced from corn harvested at 40 cm were higher than those of sheep fed silage produced from corn harvested at 25 cm. Collectively, our findings indicate that, despite the observed effects, a difference of 15 cm in cutting height results in relatively small changes in the chemical composition of corn silage and a limited effect on the nutrient intake and nitrogen balance of animals fed this silage. Moreover, although bacterial inoculation promotes an efficient fermentation, it has no marked effects on the aerobic stability of silage.(AU)

A Therapeutic Oral Vaccine Candidate against Propionibacterium acnes: Preparation and Immunological Evaluation of Nanoparticles Encapsulated Sialidase-CAMP Fusion Protein

Abstract Acne Vulgaris is a common skin disease caused by Propionibacterium acnes, an anaerobic microbiota of human skin that plays a vital role in the pathology of acne. The aim of this study was to prepare nanoparticles containing an acne recombinant protein and determine its ability as an oral acne vaccine in mice. The recombinant Sialidase-CAMP gene was expressed and purified in a prokaryotic host. The chitosan nanoparticles containing the recombinant protein were prepared, encapsulated, and administered by both oral and subcutaneous routes to Balb/c mice. Sera IgA and IgG and stool IgA titers were measured by ELISA, and the immunized mice were challenged against P. acnes. A 65 kDa recombinant protein was confirmed by SDS-PAGE and western blot. The size and zeta potential of nanoparticles were 80 nm and +18 mV, respectively. After oral immunization, the serum IgG and IgA titers were 1:3200 and 1:16, respectively, and the stool IgA titer was 1:8. In the subcutaneous route, the serum IgG titer was 1:51200. Immunized mice showed no inflammation in the ear of challenged mice. It is the first study that examines a chitosan-nanoparticulated acne fusion protein as an applicable acne vaccine candidate with appropriate immunogenicity potential. Further studies are required to validate the clinical usefulness of this vaccine candidate.

Whey Protein Isolate-Supplemented Beverage, Fermented by Lactobacillus casei BL23 and Propionibacterium freudenreichii 138, in the Prevention of Mucositis in Mice.

Mucositis is a clinically important gastrointestinal inflammatory infirmity, generated by antineoplastic drugs cytotoxic effects. The inflammatory process caused by this disease frequently leads to derangements in the alimentary tract and great malaise for the patient. Novel strategies are necessary for its prevention or treatment, as currently available treatments of mucositis have several limitations in relieving its symptoms. In this context, several research groups have investigated the use of probiotic bacteria, and in particular dairy bacterial strains. Compelling evidences reveal that milk fermented by certain probiotic bacteria has the capacity to ameliorate intestinal inflammatory disorders. In addition, innovative probiotic delivery strategies, based on probiotics incorporation into protective matrices, such as whey proteins, were able to increase the therapeutic effect of probiotic strains by providing extra protection for bacteria against environmental stresses. Therefore, in this study, we evaluated the role of the whey protein isolate (WPI), when added to skim milk fermented by Lactobacillus casei BL23 (L. casei BL23) or by Propionibacterium freudenreichii CIRM-BIA138 (P. freudenreichii 138), as a protective matrix against in vitro stress challenges. In addition, we investigated the therapeutic effect of these fermented beverages in a murine model of mucositis induced by 5-Fluorouracil (5-FU). Our results demonstrated that milk supplementation with 30% (w/v) of WPI increases the survival rate of both strains when challenged with acid, bile salts, high temperature and cold storage stresses, compared to fermented skim milk without the addition of WPI. Moreover, treatment with the probiotic beverages prevented weight loss and intestinal damages in mice receiving 5-FU. We conclude that the presence of WPI maximizes the anti-inflammatory effects of L. casei BL23, but not for P. freudenreichii 138, suggesting that whey protein enhancement of probiotic activity might be strain-dependent.

Evidências do efeito da terapia fotodinâmica sobre a Propionibacterium acnes / Evidence of the effect of photodynamic therapy on Propionibacterium acnes

Introdução: A Propionibacterium acnes é uma bactéria causadora da acne. Devido aos efeitos colaterais ou à falta de resposta ao tratamento da acne, foi proposta a terapia fotodinâmica como um tratamento alternativo para a acne. Objetivo: O objetivo foi evidenciar a ação fotodinâmica do LED vermelho 660 nm e do fotossensibilizador azul de metileno sobre Propionibacterium acnes in vitro. Métodos: Os ensaios foram constituídos por quatro grupos: 1. controle (sem aplicação de luz e sem fotossensibilizador); 2. com aplicação de luz; 3. com fotossensibilizador e sem aplicação de luz; 4. com fotossensibilizador e com aplicação de luz. Os ensaios foram submetidos a aplicação de luz por 4 ciclos de 5 minutos com intervalos de 3 minutos. Resultados: Houve redução estatisticamente significante (p<0,05) nas médias dos grupos 1, 2 e 4, ainda que o grupo 3 não tenha apresentado significância estatística, mas houve redução detectada nas médias. Conclusão: A ação fotodinâmica é eficiente para a destruição do material biológico por irradiação a 660nm atribuída ao processo de fotossensibilização pela presença do fotossensibilizador.(AU)

Introduction: Propionibacterium acnes is a bacterium that causes acne. Due to the side effects or the lack of response to acne treatment, photodynamic therapy was proposed as an alternative treatment for acne. Objective: To demonstrate the photodynamic action of the 660 nm red LED and the methylene blue photosensitizer on Propionibacterium acnes in vitro. Methods: Four groups were studied: 1. control (without light application and without photosensitizer); 2. with light application; 3. with photosensitizer and without light application; 4. with photosensitizer and light application. The assays were subjected to light application for 4 cycles of 5 minutes at 3 minute intervals. Results: There was a statistically significant reduction (p <0.05) in the means of groups 1, 2 and 4, although group 3 did not present statistical significance, but there was a reduction detected in the means. Conclusion: The photodynamic action is efficient for the destruction of the biological material by irradiation at 660nm attributed to the process of photosensitization by the presence of the photosensitizer.(AU)

Soybean whole-plant ensiled with chitosan and lactic acid bacteria: Microorganism counts, fermentative profile, and total losses.

Chitosan is a biopolymer derived from chitin deacetylation, present in the exoskeleton of crustaceans and insects. Chitosan has been evaluated as rumen modulator and silage additive due to its antimicrobial properties. The objective of this study was to determine the effects of both chitosan and a bacterial additive on microbiological quality, chemical composition, nutrient in vitro degradation, fermentative profile, and total losses of whole-soybean plant silage (SS) harvested at R6 stage. Four treatments in a factorial arrangement were randomly assigned to 40 experimental minisilos as no additives (CON), 8 g/t fresh forage of microbial inoculant (INO; Kera SIL, Kera Nutrição Animal, Bento Gonçalves, Brazil); 5 g/kg of fresh forage chitosan (CHI); and CHI + INO. Microbial inoculant was composed of Lactobacillus plantarum (4.0 × 1010 cfu/g) and Propionibacterium acidipropionici (2.6 × 1010 cfu/g). The CHI and INO alone increased counts of lactic bacteria and anaerobic bacteria and decreased counts of mold and yeast in SS. The CHI or INO alone increased in vitro degradation of dry matter, crude protein, and neutral detergent fiber, and decreased nonfiber carbohydrate content of SS. Chitosan increased NH3-N and lactate concentrations and decreased ethanol concentration in SS. The CHI increased dry matter recovery from SS; INO increased silage aerobic stability. The combination of CHI+INO showed the lowest value of gas losses. In general, the combination of CHI and INO had small positive effects on gas losses of SS; however, both CHI or INO alone improved nutrient in vitro degradation and decreased mold and yeast in SS. Chitosan or INO utilization improves SS quality.

Propionibacterium acnes Enhances the Immunogenicity of HIVBr18 Human Immunodeficiency Virus-1 Vaccine.

Immunization of BALB/c mice with HIVBr18, a DNA vaccine containing 18 CD4+ T cell epitopes from human immunodeficiency virus (HIV), induced specific CD4+ and CD8+ T cell responses in a broad, polyfunctional and persistent manner. With the aim of increasing the immunogenicity of this vaccine, the effect of Propionibacterium acnes as an adjuvant was evaluated. The adjuvant effects of this bacterium have been extensively demonstrated in both experimental and clinical settings. Herein, administration of two doses of HIVBr18, in the presence of P. acnes, increased the proliferation of HIV-1-specific CD4+ and CD8+ T lymphocytes, the polyfunctional profile of CD4+ T cells, the production of IFN-γ, and the number of recognized vaccine-encoded peptides. One of the bacterial components responsible for most of the adjuvant effects observed was a soluble polysaccharide extracted from the P. acnes cell wall. Furthermore, within 10 weeks after immunization, the proliferation of specific T cells and production of IFN-γ were maintained when the whole bacterium was administered, demonstrating a greater effect on the longevity of the immune response by P. acnes. Even with fewer immunization doses, P. acnes was found to be a potent adjuvant capable of potentiating the effects of the HIVBr18 vaccine. Therefore, P. acnes may be a potential adjuvant to aid this vaccine in inducing immunity or for therapeutic use.

Assessment of Chitosan-Based Hydrogel and Photodynamic Inactivation against Propionibacterium acnes.

Chitosan (CH) is a biopolymer that exhibits a number of interesting properties such as anti-inflammatory and antibacterial activity and is also a promising platform for the incorporation of photosensitizing agents. This study aimed to evaluate the efficacy of antimicrobial activity of chitosan hydrogel formulation alone and in combination with the methylene blue (MB) associated with antimicrobial photodynamic therapy (aPDT) against planktonic and biofilm phase of Propionibacterium acnes. Suspensions were sensitized with 12.5, 25.0, 37.5, 50.0 µg/mL of MB for 10 min and biofilms to 75, 100 and 150 µg/mL for 30 min then exposed to red light (660 nm) at 90 J/cm² and 150 J/cm² respectively. After treatments, survival fractions were calculated by counting the number of colony-forming units. The lethal effect of aPDT associated with CH hydrogel in planktonic phase was achieved with 12.5 µg/mL MB and 1.9 log10 biofilm reduction using 75 µg/mL MB. Rheological studies showed that formulations exhibited pseudoplastic non-Newtonian behavior without thixotropy. Bioadhesion test evidenced that the formulations are highly adhesive to skin and the incorporation of MB did not influence the bioadhesive force of the formulations.

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy.

Bacterial resistance to available antibiotics nowadays is a global threat leading researchers around the world to study new treatment modalities for infections. Antimicrobial photodynamic therapy (aPDT) has been considered an effective and promising therapeutic alternative in this scenario. Briefly, this therapy is based on the activation of a non-toxic photosensitizing agent, known as photosensitizer (PS), by light at a specific wavelength generating cytotoxic singlet oxygen and free radicals. Virtually all studies related to aPDT involve a huge screening to identify ideal PS concentration and light dose combinations, a laborious and time-consuming process that is hardly disclosed in the literature. Herein, we describe an antimicrobial Photodynamic Therapy (aPDT) study against Enterococcus faecalis and Propionibacterium acnes employing methylene blue, chlorin-e6 or curcumin as PS. Similarities and discrepancies between the two bacterial species were pointed out in an attempt to speed up and facilitate futures studies against those clinical relevant strains. Susceptibility tests were performed by the broth microdilution method. Our results demonstrate that aPDT mediated by the three above-mentioned PS was effective in eliminating both gram-positive bacteria, although P. acnes showed remarkably higher susceptibility to aPDT when compared to E. faecalis. PS uptake assays revealed that P. acnes is 80 times more efficient than E. faecalis in internalizing all three PS molecules. Our results evidence that the cell wall structure is not a limiting feature when predicting bacterial susceptibility to aPDT treatment.

Improvement of Mesenchymal Stem Cell Immunomodulatory Properties by Heat-Killed Propionibacterium acnes via TLR2.

Mesenchymal stem cells (MSCs) are an essential tool for regenerative medicine, which aims to develop new technologies to improve their effects to obtain useful transplantation results. MSC immunomodulatory role has been just demonstrated; however, how they react when they are stimulated by an adjuvant is poorly understood. Our group showed the adjuvant effect of killed Propionibacterium acnes (P. acnes) on hematopoietic stem cells. As these cells share the same MSCs bone marrow (BM) site and interact with each other, here we evaluated the P. acnes and its soluble polysaccharide (PS) effect on MSCs and their immunomodulatory role in a murine model of traumatic brain injury (TBI). The bacteria increased the absolute number of MSCs, including MSC subpopulations, and maintained MSC plasticity. P. acnes and PS enhanced MSC proliferation and improved their immunomodulatory effect. P. acnes-MSC and PS-MSC transplantation increased anti-inflammatory cytokine expression and diminished pro-inflammatory cytokine expression after injury. This effect seemed to be mediated via TLR2 since P. acnes-KOTLR2-MSC transplantation decreased TGF-ß and IL-10 expression. Increasing in neural stem cells and neuroblasts after PS-MSC transplantation was also observed. The adjuvant effect of P. acnes is an alternative means of expanding MSCs and important to identify their subpopulations to know better their role under exogenous stimuli including inflammation resolution in an experimental model.

Subclinical Propionibacterium acnes infection estimation in the intervertebral disc (SPInE-ID): protocol for a prospective cohort.

INTRODUCTION: Low back pain and vertebral endplate abnormalities are common conditions within the population. Subclinical infection caused by indolent pathogens can potentially lead to these findings, with differentiation between them notably challenging from a clinical perspective. Progressive infection of the intervertebral disc has been extensively associated with increasing low back pain, with Propionibacterium acnes specifically implicated with in relation to sciatica. The main purpose of this study is to identify if the presence of an infective pathogen within the intervertebral disc is primary or is a result of intraoperative contamination, and whether this correlates to low back pain. METHODS AND ANALYSIS: An open prospective cohort study will be performed. Subjects included within the study will be between the ages of 18 and 65 years and have a diagnosis of lumbar disc herniation requiring open decompression surgery. Excised herniated disc fragments, muscle and ligamentum flavum samples will be collected during surgery and sent to microbiology for tissue culture and pathogen identification. Score questionnaires for pain, functionality and quality of life will be given preoperatively and at 1, 3, 6 and 12 months postoperatively. A MRI will be performed 12 months after surgery for analysis of Modic changes and baseline comparison. The primary endpoint is the rate of disc infection in patients with symptomatic degenerative disc disease. The secondary endpoints will be performance scores, Modic incidence and volume. ETHICS AND DISSEMINATION: This study was approved by our Institutional Review Board and was only initiated after it (CAAE 65102617.2.0000.0071). Patients agreeing to participate will sign an informed consent form before entering the study. Results will be published in a peer reviewed medical journal irrespective of study findings. If shown to be the case, this would have profound effects on the way physicians treat chronic low back pain, even impacting health costs. TRIALS REGISTRATION NUMBER: NCT0315876; Pre-results.