Nanoparticle-Hydrogel Systems Containing Platensimycin for Local Treatment of Methicillin-Resistant Staphylococcus aureus Infection.

Skin and soft tissue infections require effective and sustained topical administration. Platensimycin (PTM) is a natural drug lead that targets bacterial fatty acid synthases and has a great potential to treat infections caused by methicillin-resistant Staphylococcus aureus (MRSA). To facilitate the use of PTM against local MRSA infections, we prepared polyacrylamide hydrogels containing polyamidoamine (PAMAM)/PTM nanoparticles (NP-gel(PTM)) for the controlled release of PTM. NP-gel(PTM) can continuously inhibit the growth of MRSA and its biofilm formation in simulated drug flow models in vitro. In situ implantation of NP-gel(PTM) could treat MRSA-infected subcutaneous soft tissues without toxicity. For MRSA-infected skin wounds, NP-gel(PTM) not only showed strong anti-MRSA activity but also accelerated more wound healing than the widely used antibiotic mupirocin. Collectively, PTM is expected to be used in this safe and effective NP-gel delivery platform for the treatment of local infections, which might help to alleviate the current antibiotic resistance crisis.

Recombinant production of Trx-Ib-AMP4 and Trx-E50-52 antimicrobial peptides and antimicrobial synergistic assessment on the treatment of methicillin-resistant Staphylococcus aureus under in vitro and in vivo situations.

PURPOSE: The production of alternative novel antimicrobial agents is considered an efficient way to cope with multidrug resistance among pathogenic bacteria. E50-52 and Ib-AMP4 antimicrobial peptides (AMPs) have illustrated great proven antibacterial effects. The aim of this study was recombinant production of these AMPs and investigation of their synergistic effects on methicillin-resistant Staphylococcus aureus (MRSA). METHOD: At first, the codon optimized sequences of the Ib-AMP4 (UniProt: 024006 (PRO_0000020721), and E50-52 (UniProtKB: P85148) were individually ligated into the pET-32α vector and transformed into E. coli. After the optimization of production and purification steps, the MIC (Minimum inhibitory concentration), time kill and growth kinetic tests of recombinant proteins were determined against MRSA. Finally, the in vivo wound healing efficiency was tested. RESULTS AND CONCLUSION: The recorded MIC of recombinant Trx-Ib-AMP4, Trx-E50-52 against MRSA bacterium were 0.375 and 0.0875 mg/mL respectively. The combination application of the produced AMPs by the checkerboard method confirmed their synergic activity. The results of the time-kill showed sharply decrease of the number of viable cells with over five time reductions in log10 CFU/mL by the combination of Trx-E50-52 and Trx-IbAMP4 at 2 × MIC within 240 min. The growth kinetic results confirmed the combination of Trx-E50-52 and Trx-IbAMP4 had much greater success in the reduction of over 50 % of MRSA suspensions' turbidity within the first hour. Wound healing assay and histological analysis of infected mice treated with Trx-Ib-AMP4 or Trx-E50-52 compared with those treated with a combination of Trx-Ib-AMP4 and Trx-E50-52 showed significant synergic effects.

The biological synthesis of gold/perlite nanocomposite using Urtica dioica extract and its chitosan-capped derivative for healing wounds infected with methicillin-resistant Staphylococcus aureus.

The preparation of ointments from natural compounds is essential for accelerating infected wounds. This study investigated the effects of topical uses of gold nanoparticles (Au)/perlite (Au/Perl) nanocomposites (NCs) by the help of Urtica dioica extract and its chitosan-capped derivative (Chit) on methicillin-resistant Staphylococcus aureus (MRSA)-infected wound healing in a mouse model. Furthermore, Au/Perl/Chit nanocomposite was prepared using protonated chitosan solution. The physicochemical properties of the as-synthesized nanocomposites were also investigated. The effects of Au/Perl/Chit NC were assessed by antibacterial, histopathological parameters as well as molecular evaluations. Then, they were compared with synthetic agent of mupirocin. The results revealed that Au/Perl NC was mesoporous and spherical in a range of 13-15 nm. Topical administration of Au/Perl/Chit ointment accelerated wound healing by reducing bacteria colonization and wound rate enhancing collagen biosynthesis and re-epithelialization, the expressions of IL-10, PI3K, AKT, bFGF, and COL1A genes, which is in agreement with the obtained results for mupirocin. In conclusion, the results strongly demonstrated that administration of ointments prepared from Au/Perl and Au/Perl/Chit nanocomposites stimulates MRSA-infected wound healing by decreasing the length of healing time and regulating PI3K/AKT/bFGF signaling pathway and is a promising candidate in stimulating MRSA-infected wound regeneration.

Antimicrobial and antibiofilm photodynamic therapy against vancomycin resistant Staphylococcus aureus (VRSA) induced infection in vitro and in vivo.

Biofilm mediated infection caused by multi-drug resistant bacteria are difficult to treat since it protects the microorganisms by host defense system, making them resistant to antibiotics and other antimicrobial agents. Combating such type of nosocomial infection, especially in immunocompromised patients, is an urgent need and foremost challenge faced by clinicians. Therefore, antimicrobial photodynamic therapy (aPDT) has been intensely pursued as an alternative therapy for bacterial infections. aPDT leads to the generation of reactive oxygen species (ROS) that destroy bacterial cells in the presence of a photosensitizer, visible light and oxygen. Here, we elucidated a possibility of its clinical application by reducing the treatment time and exposing curcumin to 20 J/cm2 of blue laser light, which corresponds to only 52 s to counteract vancomycin resistant Staphylococcus aureus (VRSA) both in vitro and in vivo. To understand the mechanism of action, the generation of total reactive oxygen species (ROS) was quantified by 2'-7'-dichlorofluorescein diacetate (DCFH-DA) and the type of phototoxicity was confirmed by fluorescence spectroscopic analysis. The data showed more production of singlet oxygen, indicating type-II phototoxicity. Different anti-biofilm assays (crystal violet and congo red assays) and microscopic studies were performed at sub-MIC concentration of curcumin followed by treatment with laser light against preformed biofilm of VRSA. The result showed significant reduction in the preformed biofilm formation. Finally, its therapeutic potential was validated in skin abrasion wistar rat model. The result showed significant inhibition of bacterial growth. Furthermore, immunomodulatory analysis with rat serum was performed. A significant reduction in expression of proinflammatory cytokines TNF-α and IL-6 were observed. Hence, we conclude that curcumin mediated aPDT with 20 J/cm2 of blue laser treatment (for 52 s) could be used against multi-drug resistant bacterial infections and preformed biofilm formation as a potential therapeutic approach.

In vitro efficacy of Azadirachta indica leaf extract against methicillin resistant Staphylococci isolated from skin infection.

In this cross-sectional study, the isolation and identification of Methicillin Resistant Staphylococcus aureus (MRSA) and Methicillin Resistant S. epidermidis (MRSE) was described from skin infections (n=100). Initial isolation was done by conventional procedures followed by amplification/ sequence analysis of 16S rRNA. Methicillin resistance was determined using cefoxitin discs and resistant isolates were screened for mec-A gene followed by Minimum Inhibitory Concentrations (MIC) determination of vancomycin. In second phase, we investigated extract of Azadirachta indica leaves using Fourier Transformed Infrared Spectroscopy (FTIR-Spectroscopy) and investigated in vitro activity. Initially, total of 28 Staphylococci were identified. 16S rRNA gene sequence confirmed S. aureus (22), S. epidermidis (3) and S. saprophyticus (3) isolates. Cefoxitin discs showed (7/22) MRSA, (3/3) (MRSE) and none of the methicillin resistant S. saprophyticus. MRSA and MRSE isolates showed presence of mec-A gene. However, all isolates were sensitive to vancomycin MIC (0.5-2µg/mL) and sensitive to Linezolid. FTIR-Spectroscopy of A. indica indicated the presence of azadirachtin and nimbolinin. The mean zone of inhibition was measured 14.23±1.37 and 13.66±0.70 against MRSA and MRSE isolates, respectively. Altogether, MRSA and MRSE is significant public health concern. However, vancomycin and linezolid were found effective and extract of A. indica showed in vitro effects.

Development of Emulgel Delivery of Mupirocin for Treatment of Skin Infection.

AIM: To design controlled release topical delivery of mupirocin for the treatment of skin infection. BACKGROUND: Mupirocin is an antibacterial drug. Mupirocin works to kill the bacteria, which include strains of Staphylococcus aureus and Streptococcus pyogenes. It is also used for the treatment of inflammation of a hair follicle. The half-life of mupirocin is only 20-40 min. It has very slight solubility in water. Patent literature had shown work on ointment, antibiotic composition, nasal and topical composition. Emulgel is a duel control release system for the topical delivery of hydrophobic drugs. OBJECTIVE: The objective was to formulate emulgel with controlled delivery of mupirocin using Sepineo P 600. METHODS: Soya oil, tween 80 and polyethylene glycol 400 (Oil:Surfactant:Cosurfactant) were used for emulsion formulation. Emulgel was optimized by 32 factorial design. Sepineo P 600 and hydroxy propyl methyl cellulose K4M were used as independent variables. Drug excipient compatibility analysis was carried out by FTIR, UV and DSC spectra. Emulgel was evaluated for its physical characterization, in vitro release, ex vivo release, antimicrobial and anti-inflammatory study. RESULTS: DSC, UV and FTIR analysis confirmed drug excipient compatibility. FE SEM showed a size range between 228-255 nm. Zeta potential was found to be -25.1 mV, which showed good stability of the emulsion. Design expert software showed F2 as an optimized batch. Release studies indicated that the controlled release of drugs forms Sepineo P 600 gel due to its higher gelling capacity. Batch F2 showed comparable results with marketed formulation against Staphylococcus aureus. For batch F2, 40 µg/ml was the minimal inhibitory concentration. CONCLUSION: Antimicrobial and anti-inflammatory study proved successful development of stably controlled release mupirocin emulgel.

Microbiologic characteristics and antibiotic resistance rates of diabetic foot infections.

PURPOSE: the purpose of this research was to identify the sociodemographic and microbiological characteristics and antibiotic resistance rates of patients with diabetic foot infections, hospitalized in an emergency reference center. METHODS: it was an observational and transversal study. The sociodemographic data were collected by direct interview with the patients. During the surgical procedures, specimens of tissue of the infected foot lesions were biopsied to be cultured, and for bacterial resistance analysis. RESULTS: the sample consisted of 105 patients. The majority of patierns were men, over 50 years of age, married and with low educational level. There was bacterial growth in 95 of the 105 tissue cultures. In each positive culture only one germ was isolated. There was a high prevalence of germs of the Enterobacteriaceae family (51,5%). Gram-negative germs were isolated in 60% of cultures and the most individually isolated germs were the Gram-positive cocci, Staphylococcus aureus (20%) and Enterococcus faecalis (17,9%). Regarding antibiotic resistance rates, a high frequency of Staphylococcus aureus resistant to methicillin (63,0%) and to ciprofloxacin (55,5%) was found; additionally, 43,5% of the Gram-negative isolated germs were resistant to ciprofloxacin. CONCLUSIONS: the majority of patients were men, over 50 years of age, married and with low educational level. The most prevalent isolated germs from the infected foot lesions were Gram-negative bacteria, resistant to ciprofloxacin, and the individually most isolated germ was the methicillin resistant Staphylococcus aureus.

Bioshell calcium oxide (BiSCaO) for cleansing and healing Pseudomonas aeruginosa-infected wounds in hairless rats.

BACKGROUND: Scallop shell powder is called bioshell calcium oxide (BiSCaO), which is known to possess deodorizing properties and broad antimicrobial activity against various pathogenic microbes, including viruses, bacteria, spores, and fungi. OBJECTIVE: This study aims to investigate the applications of BiSCaO suspension cleansing in clinical situations, for instance for the prevention and treatment of infections in chronic wounds in healing-impaired patients, without delaying wound healing. METHODS: The bactericidal activities of 1000 ppm BiSCaO suspension; 500 ppm hypochlorous acid; 1000 ppm povidone iodine; and saline were compared to evaluate in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. RESULTS: Cleansing of the infected wounds with BiSCaO suspension daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts, in comparison to hypochlorous acid, povidone iodine, and saline. Furthermore, histological examinations showed significantly advanced granulation tissue and capillary formation in the wounds cleansed with BiSCaO suspension than in those cleansed with the other solutions. CONCLUSIONS: This study suggested that the possibility of using BiSCaO suspension as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects on wound repair.

Microbiologic characteristics and antibiotic resistance rates of diabetic foot infections / Perfil microbiológico e de resistência bacteriana no pé diabético infectado

ABSTRACT Purpose: the purpose of this research was to identify the sociodemographic and microbiological characteristics and antibiotic resistance rates of patients with diabetic foot infections, hospitalized in an emergency reference center. Methods: it was an observational and transversal study. The sociodemographic data were collected by direct interview with the patients. During the surgical procedures, specimens of tissue of the infected foot lesions were biopsied to be cultured, and for bacterial resistance analysis. Results: the sample consisted of 105 patients. The majority of patierns were men, over 50 years of age, married and with low educational level. There was bacterial growth in 95 of the 105 tissue cultures. In each positive culture only one germ was isolated. There was a high prevalence of germs of the Enterobacteriaceae family (51,5%). Gram-negative germs were isolated in 60% of cultures and the most individually isolated germs were the Gram-positive cocci, Staphylococcus aureus (20%) and Enterococcus faecalis (17,9%). Regarding antibiotic resistance rates, a high frequency of Staphylococcus aureus resistant to methicillin (63,0%) and to ciprofloxacin (55,5%) was found; additionally, 43,5% of the Gram-negative isolated germs were resistant to ciprofloxacin. Conclusions: the majority of patients were men, over 50 years of age, married and with low educational level. The most prevalent isolated germs from the infected foot lesions were Gram-negative bacteria, resistant to ciprofloxacin, and the individually most isolated germ was the methicillin resistant Staphylococcus aureus.

RESUMO Objetivo: identificar o perfil sociodemográfico, microbiológico e de resistência bacteriana em pacientes com pé diabético infectado. Métodos: tratou-se de estudo observacional, transversal que avaliou os perfis sóciodemográfico e microbiológico de pacientes portadores de pé diabético infectado internados em Pronto Socorro de referência. Os dados sociodemográficos foram coletados por meio de entrevista. Foram colhidos, durante os procedimentos cirúrgicos, fragmentos de tecidos das lesões podais infectadas para realização de cultura/antibiograma. Resultados: a amostra foi composta por 105 pacientes. O perfil sociodemográfico mais prevalente foi o de pacientes do sexo masculino, acima dos 50 anos, casados e com baixa escolaridade. Das 105 amostras de fragmentos de tecidos colhidos para realização de cultura e antibiograma, 95 foram positivas, com crescimento de um único germe em cada um dos exames. Houve predomínio de germes da família Enterobacteriaceae (51,5%). Germes Gram-negativos foram isolados em 60,0% das culturas e os espécimes mais isolados individualmente foram os cocos Gram-positivos, Staphylococcus aureus (20,0%) e Enterococcus faecalis (17,9%). Considerando-se os perfis de resistência bacteriana, verificou-se alta taxa de Staphylococcus aureus resistente à meticilina (63,0%) e à ciprofloxacino (55,5%); verificou-se, também, que 43,5% dos germes Gram-negativos eram resistentes à ciprofloxacino. Conclusões: o perfil sociodemográfico majoritário, foi o de homens, com mais de 50 anos e com baixa escolaridade. Concluímos que os germes mais prevalentes nas lesões podais dos pacientes diabéticos foram os Gram-negativos, resistentes ao ciprofloxacino e que o germe mais isolado individualmente foi o Staphylococcus aureus resistente à meticilina.

Local Treatment of Local Staphylococcal Infection with Complex Preparations Based on Metal Nanoparticles in the Experiment.

Antibacterial activity of powdered preparations based on copper and silver nanoparticles was compared with activity of the reference preparation Baneocin on the model of local staphylococcal infection in white rats. The developed preparations exhibited pronounced antibacterial activity against methicillin-resistant S. epidermidis strains in vivo significantly (p<0.001) exceeding that of Baneocin, reduced microbial contamination of the wound on day 5 of study by 2 lg and more in comparison with bacterial load before treatment, and provided effective decontamination of the wound within 7-10 days.

Liposomes augment biological benefits of curcumin for multitargeted skin therapy.

Curcumin, a multi-targeting pharmacologically active compound, is a promising molecule for the treatment of skin inflammation and infection in chronic wounds. However, its hydrophobic nature remains to be a challenge in development of its pharmaceutical products, including dermatopharmaceuticals. Here we propose deformable liposomes (DLs) as a mean to overcome the curcumin limitations in skin treatment. We explored the properties and biological effects of curcumin containing DLs (curcumin-DLs) with varying surface charge by preparing the neutral (NDLs), cationic (CDLs) and anionic (ADLs) nanocarriers. The vesicles of mean diameter 200-300 nm incorporated high curcumin load mirroring the type of employed surfactant. Curcumin-CDLs provided the most sustained ex vivo penetration of curcumin through the full thickness human skin. Although the curcumin-CDLs were the most potent regarding the in vitro anti-inflammatory activity, all curcumin-DLs were superior to curcumin in solution (control). No cytotoxicity in human skin fibroblasts was detected. All DLs significantly inhibited bacterial Staphylococcus aureus and Streptococcus pyogenes growth in vitro. The curcumin-CDLs were found superior to other DLs. The incorporation of curcumin in DLs enabled both its sustained skin penetration and enhancement of its biological properties. Cationic nanocarriers enhanced the activities of curcumin to the greatest extent.

The bactericidal effect of lysostaphin coupled with liposomal vancomycin as a dual combating system applied directly on methicillin-resistant Staphylococcus aureus infected skin wounds in mice.

BACKGROUND AND AIM: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common causes of surgical infection, and its resistance to numerous conventional antibiotics makes treatment difficult. Although vancomycin is often an effective agent for the initial therapy of MRSA, clinical failure sometimes occurs. Therefore, there is an urgent need to develop better therapies. Here, we prepared some vancomycin-loaded nanoliposomes coupled with anti-staphylococcal protein (lysostaphin) and evaluated their in vitro and in vivo efficacy as a topical MRSA therapy. METHODS: Vancomycin was encapsulated in liposomes, and the coupling of lysostaphin with the surface of liposomes was carried out through cyanuric functional groups. The bactericidal efficacies and a full characterization were evaluated. To define different nanoliposomal-bacterium interactions and their bactericidal effect, flow cytometry was employed. Finally, in vivo, the topical antibacterial activity of each formulation was measured against surgical wound MRSA infection in a mouse model. RESULTS: High encapsulation and conjugation efficiency were achieved for all formulations. All the formulations showed a significant reduction in bacterial counts (p<0.05). The targeted liposomes more effectively suppress bacterial infection in vitro and in vivo relative to equivalent doses of untargeted vancomycin liposome. The flow cytometry results confirmed liposome-bacterium interactions, which increased during the incubation time. The maximum binding rate and the bactericidal effect were significantly higher in targeted liposomes (p<0.05) compared with control liposomes. CONCLUSION: Our data suggest a novel nano-vehicle (lysostaphin-conjugated coupled liposomal vancomycin) which could be used as a great topical antimicrobial construct for treatment of MRSA skin infections.

The incidence and patient outcomes of ABSSSI by iclaprim MIC values in the phase 3 REVIVE trials for treatment of acute bacterial skin and skin structure infections.

The incidence and patient outcomes of Staphylococcus aureus isolates by iclaprim MIC was determined among patients from two phase 3 studies for the treatment of acute bacterial skin and skin structure infections (ABSSSI), REVIVE-1 and -2. Iclaprim MIC90 values were 0.12 µg ml-1 for S. aureus (0.12 µg ml-1 against methicillin-sensitive and 0.25 µg ml-1 against methicillin-resistant S. aureus). The incidence of culture confirmed S. aureus isolates among patients with ABSSSI with an iclaprim MIC > 8 µg ml-1 was 2.0  % (16/790). The clinical outcomes varied by MICs for early clinical response (63-100  %), end of therapy response (81-100  %) and the test of cure response (75-100  %). For microbiological outcomes of these infections, the end of therapy response was 80-100  % and the test of cure response was 88-100  %.

Liposomes containing biosurfactants isolated from Lactobacillus gasseri exert antibiofilm activity against methicillin resistant Staphylococcus aureus strains.

Staphylococcus aureus is the major causative agent of skin and soft tissue infections, whose prevention and treatment have become more difficult due to the emergence of antibiotic-resistant strains. In this regard, the development of an effective treatment represents a challenge that can be overcome by delivering new antibiofilm agents with appropriate nanocarriers. In this study, a biosurfactant (BS) isolated from Lactobacillus gasseri BC9 and subsequently loaded in liposomes (LP), was evaluated for its ability to prevent the development and to eradicate the biofilm of different methicillin resistant S. aureus (MRSA) strains. BS from L. gasseri BC9 was not cytotoxic and was able to prevent formation and to eradicate the biofilm of different MRSA strains. BS loaded liposomes (BS-LP) presented a mean diameter (lower than 200 nm) suitable for topical administration and a low polydispersity index (lower than 0.2) that were maintained over time for up 28 days. Notably, BS-LP showed higher ability than free BS to inhibit S. aureus biofilm formation and eradication. BS-LP were loaded in lyophilized matrices able to quickly dissolve (dissolution time lower than 5 s) upon contact with exudate, thus allowing vesicle reconstitution. In conclusion, in this work, we demonstrated the antibiofilm activity of Lactobacillus-derived BS and BS-LP against clinically relevant MRSA strains. Furthermore, the affordable production of lyophilized matrices containing BS-LP for local prevention of cutaneous infections was established.

Carriage of Staphylococcus schleiferi from canine otitis externa: antimicrobial resistance profiles and virulence factors associated with skin infection.

The recent emergence of Staphylococcus schleiferi in dogs with otitis externa or skin and soft tissue infections has become a significant zoonotic issues. In the current study, we investigated 1) the carriage rates of S. schleiferi among major staphylococci in healthy dogs and dogs with otitis externa, 2) antibiotic susceptibility profiles of S. schleiferi, particularly methicillin resistance (MR), and 3) virulence factors associated with skin and soft tissue infections such as ability to form biofilm, resistance to cationic antimicrobial peptides (CAMPs), and carriage of staphylococcal enterotoxin genes. Among the 21 S. schleiferi isolates, 5 isolates (24%) were determined to be methicillin-resistant (MRSS). Staphylococcal cassette chromosome mec (SCCmec) typing revealed the presence of SCCmec type V in 4 MRSS isolates and type VII in one MRSS. Higher levels of antibiotic resistance, especially multidrug resistance, were observed in MRSS isolates compared to the methicillin-susceptible S. schleiferi (MSSS) isolates. In addition, MRSS isolates exhibited enhanced ability to form biofilm under static condition and all the 5 MRSS isolates carried three or more enterotoxin genes. However, there were no significant differences in resistance to CAMPs between MRSS and MSSS isolates. These findings suggest that coagulase-negative S. schleiferi is becoming more prevalent in canine otitis externa cases. Our results also highlight the presence of multidrug-resistant MRSS isolates with enhanced biofilm production and carriage of multiple enterotoxins.

The atopic dermatitis-like lesion and the associated MRSA infection and barrier dysfunction can be alleviated by 2,4-dimethoxy-6-methylbenzene-1,3-diol from Antrodia camphorata.

BACKGROUND: Atopic dermatitis (AD) is an inflammatory skin disease with an associated barrier dysfunction and Staphylococcus aureus infection. The mainstay steroid and calcineurin inhibitor therapy shows some adverse effects. 2,4-Dimethoxy-6-methylbenzene-1,3-diol (DMD) is a benzenoid isolated from Antrodia camphorata. OBJECTIVE: We investigated the inhibitory effect of DMD on methicillin-resistant S. aureus (MRSA), the chemokine production in stimulated keratinocytes, and the AD-like lesion found in ovalbumin (OVA)-sensitized mice. METHODS: The antimicrobial effect and cutaneous barrier function were evaluated using an in vitro culture model and an in vivo mouse model of AD-like skin. RESULTS: DMD exhibited a comparative minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against MRSA with nalidixic acid, a conventional antibiotic. The MIC and MBC for DMD was 78.1 and 156.3 µg/ml, respectively. DMD also showed the ability to eliminate the clinical bacteria isolates with resistance to methicillin and vancomycin. The DNA polymerase and gyrase inhibition evoked by DMD for bacterial lethality was proposed. In the activated keratinocytes, DMD stopped the upregulation of chemokines (CCL5 and CCL17) and increased the expression of differentiation proteins (filaggrin, involucrin, and integrin ß-1). Topical application of DMD facilely penetrated into the skin, with AD-like skin displaying 2.5-fold greater permeation than healthy skin. The in vivo assessment using the mouse model with OVA sensitization and MRSA inoculation revealed a reduction of transepidermal water loss (TEWL) and bacterial burden by DMD by about 2- and 100-fold, respectively. Differentiation proteins were also restored after topical DMD delivery. CONCLUSION: Our data demonstrated an advanced concept of AD treatment by combined barrier repair and bacterial eradication with a sole agent for ameliorating the overall complications.

Clinical and microbiological properties of Staphylococcus lugdunensis skin infections.

Staphylococcus lugdunensis is an emerging pathogen in skin and soft tissue infections that was previously considered a commensal. The aim of this study was to elucidate the characteristics of skin infections by S. lugdunensis and its appropriate management, in a tertiary referral medical center. The clinical files, bacterial cultures and histopathology reports of all S. lugdunensis isolates from skin infections over a period of 8 years (September 2009-September 2017) were reviewed. S. lugdunensis was isolated from 29 patients with skin infections, aged 7-89 years (mean 33.3 years). A state of immune suppression (drug-induced, malignancy or diabetes) was present in five patients (17%). Folliculitis and cutaneous pustulosis were the most common presentations (16 cases, 55%), followed by secondary infection of hidradenitis suppurativa (five cases, 17%). Other sources of isolation were infected molluscum contagiosum (two cases), folliculitis decalvans (one case), dissecting cellulitis (one case), abscess (one case), cyst (one case), impetigo (one case) and granuloma after trauma (one case). The in vitro antibiotic sensitivity tests showed susceptibility to most tested antibiotics, although a few isolates were resistant to gentamycin, penicillin and oxacillin. In 19 of 20 patients for whom follow ups were available, cutaneous manifestations improved or resolved with proper local and/or oral antibiotic therapy. S. lugdunensis may play a role as a primary or secondary pathogen in various skin infections, most commonly folliculitis and pustulosis. Proper antibiotic therapy may lead to improvement or resolution.

[Effect of ozone on Staphylococcus aureus colonization in patients with atopic dermatitis].

OBJECTIVE: To verify the effect of ozone on Staphylococcus aureus (S. aureus) colonization in patients with atopic dermatitis (AD) and its correlation with the patient's status.
 Methods: A total of 12 patients with moderate or severe AD, aged from 6 to 65 years, were recruited from outpatient of the Third Xiangya Hospital. The treatment sides were showered with ozonated water and smeared with ozonated oil for 7 days (twice a day), while the control sides were washed with warm running water and smeared with base oil. At different time points, the severity scoring of atopic dermatitis (SCORAD) scores, sleep and pruritus scores were assessed and compared between the two sides. Meanwhile, plate cultivation was used to quantitatively detect the changes of S. aureus colonization in skin lesions.
 Results: After 7 days treatment, erythema and pimples were decreased in the treatment sides. The clear skin texture, smooth skin, improved skin lesions were also observed by dermoscopic examination. The results of reflectance confocal microscopy (RCM) demonstrated that the parakeratosis was improved, the structures were clearer, and the inflammatory cells infiltration was reduced after ozone treatment for 7 days. After ozone treatment for 3 and 7 days, the S. aureus colonization in the treatment sides decreased by (75.55±21.81)% and (97.24±2.64)% respectively. Compared to that of control sides, the percentage of S. aureus colony after ozone treatment for 7 days decreased significantly (P<0.01). After ozone treatment for 7 days, the SCORAD scores, sleep and pruritus scores were significantly decreased (all P<0.01). There was a linear correlation between the decreasing percentage of S. aureus colony and the declining percentage of SCORAD scores in AD patients.
 Conclusion: Topical ozone therapy can effectively reduce S. aureus colony in skin lesions and alleviate the severity of AD patients with moderate to severe degree.

An in vitro evaluation of the efficacy of tedizolid: implications for the treatment of skin and soft tissue infections.

Skin and soft tissue infections (SSTI) are among the most commonly occurring infections and evidence suggests that these are increasing world-wide. The aetiology is diverse, but Staphylococcus aureus predominate and these are often resistant to antimicrobials that were previously effective. Tedizolid is a new oxazolidinone-class antibacterial indicated for the treatment of adults with SSTI caused by Gram-positive pathogens, including S. aureus. The aim of this study was to evaluate the in vitro efficacy of tedizolid in comparison to other clinically used antibacterials against antibiotic sensitive- and resistant-staphylococci, grown in planktonic cultures and as biofilms reflecting the growth of the microorganism during episodes of SSTI. Against a panel of 66 clinical staphylococci, sensitivity testing revealed that a lower concentration of tedizolid was required to inhibit the growth of staphylococci compared to linezolid, vancomycin and daptomycin; with the tedizolid MIC50 being 8-fold (S. aureus) or 4-fold (S. epidermidis) below that obtained for linezolid. In addition, cfr+ linezolid-resistant strains remained fully susceptible to tedizolid. Against S. aureus biofilms, 10×MIC tedizolid was superior or comparable with 10×MIC comparator agents in activity, and superior to 10×MIC linezolid against those formed by S. epidermidis (65 vs. 33% reduction, respectively). Under flow-conditions both oxazolidinones at 10×MIC statistically out-performed vancomycin in their ability to reduce the viable cell count within a S. aureus biofilm with fewer the 12% of cells surviving compared to 63% of cells. In conclusion, tedizolid offers a realistic lower-dose alternative agent to treat staphylococcal SSTI, including infections caused by multi-drug resistant strains.