In vitro analysis of interactions between Pseudomonas aeruginosa and Candida albicans treated with silver sulfadiazine in wound infections.

Background: Microorganisms tend to rely on close relationships with other species to survive. Consequently, biofilms formed by interactions of different species have been shown to delay the wound healing process. Studies suggest these mixed-population infections contribute to the development of drug resistance and inhibition of host immune response. Silver sulfadiazine (SSD) has been shown to effectively decrease the risk of infection in an open wound. Typically, these are bacterial wound infections; however, the role of fungal species needs further attention. Objectives: The purpose of this in vitro study was to determine the effect of SSD on interactions between Pseudomonas aeruginosa 09-009 (PA1) or P. aeruginosa 09-010 (PA2) and Candida albicans ATTC 64550 (CA). Methods: A mixture of 4 mL of tryptic soy broth (TSB) and 100 µL of CA and/or PA1 or PA2 (∼106 log cfu/mL) inoculums were deposited into either wells or vials. The wells or vials were then sonicated (50 W for 10 s) to separate microorganisms attached to the walls. After incubation, cell counts were performed at 24 and 48 h for each microorganism using specific media. Results: Our results show that without SSD treatment, P. aeruginosa exhibits an inhibitory effect on C. albicans. Treatment with SSD demonstrated significant reduction of P. aeruginosa; however, C. albicans persisted. This experiment demonstrates that SSD was effective in reducing the bioburden of both P. aeruginosa strains after 24 and 48 h; however, it was not as effective in reducing C. albicans. Conclusions: The data suggest that for polymicrobial mixed infections containing Pseudomonas spp. and C. albicans, treatment with SSD may be beneficial but does not provide adequate microorganism eradication. As such, added treatments that provide coverage for Candida infection are necessary. Additional in vivo studies are needed to obtain a better understanding of the complex interactions between these organisms.

Model to Inhibit Contraction in Third-Degree Burns Employing Split-Thickness Skin Graft and Administered Bone Marrow-Derived Stem Cells.

Third-degree burns typically result in pronounced scarring and contraction in superficial and deep tissues. Established techniques such as debridement and grafting provide benefit in the acute phase of burn therapy, nevertheless, scar and contraction remain a challenge in deep burns management. Our ambition is to evaluate the effectiveness of novel cell-based therapies, which can be implemented into the standard of care debridement and grafting procedures. Twenty-seven third-degree burn wounds were created on the dorsal area of Red Duroc pig. After 72 h, burns are surgically debrided using a Weck knife. Split-thickness skin grafts (STSGs) were then taken after debridement and placed on burn scars combined with bone marrow stem cells (BM-MSCs). Biopsy samples were taken on days 17, 21, and 45 posttreatment for evaluation. Histological analysis revealed that untreated control scars at 17 days are more raised than burns treated with STSGs alone and/or STSGs with BM-MSCs. Wounds treated with skin grafts plus BM-MSCs appeared thinner and longer, indicative of reduced contraction. qPCR revealed some elevation of α-SMA expression at day 21 and Collagen Iα2 in cells derived from wounds treated with skin grafts alone compared to wounds treated with STSGs + BM-MSCs. We observed a reduction level of TGFß-1 expression at days 17, 21, and 45 in cells derived from wounds treated compared to controls. These results, where the combined use of stem cells and skin grafts stimulate healing and reduce contraction following third-degree burn injury, have a potential as a novel therapy in the clinic.

Response to intervention for high school students: examining baseline word reading skills and reading comprehension outcomes.

The purpose of this post hoc analysis was to analyze if pre-intervention word reading skills contributed to intervention response on reading comprehension outcomes. High school students with reading difficulties were randomized to a business as usual (BaU) or treatment condition that provided 2 years of an intensive, multicomponent word reading and reading comprehension intervention. Participants were assessed on measures of word reading and reading comprehension for pretest and reading comprehension only for posttest. Findings revealed no statistically significant differences with word-level fluency modeled as a continuous variable between treatment and control on reading comprehension. Regardless of assignment to condition, higher word-level fluency scores predicted higher posttest outcomes on years 1 and 2 reading comprehension scores.

A novel dressing with silver to treat meticillin-resistant Staphylococcus aureus biofilm infection in a pig model.

OBJECTIVE: The purpose of this study was to use an in vivo biofilm porcine model to examine a new polyvinyl alcohol-based gelling fibre dressing with silver and compare it to other commercial dressings containing: polyvinyl alcohol-based gelling fibre without silver; carboxymethyl cellulose-based fibre with silver, benzethonium chloride and ethylenediaminetetraacetic acid; and untreated control. METHODS: A total of 52 deep partial-thickness wounds (10x7x0.5mm) were created on each of three animals and inoculated with 25µl of meticillin-resistant Staphylococcus aureus (MRSA) (106 colony forming units (CFU)/ml). Wounds were covered for 24 hours to allow biofilm formation and were randomly designated to one of the four treatments. Samples were recovered for microbiological and histological analysis on days 3, 5 and 7 post-treatment. RESULTS: Polyvinyl alcohol-based gelling fibre dressing with silver was able to significantly reduce biofilm more effectively than the other treatment groups. By day 7, wounds treated with the dressing had a 2.72±0.01 log CFU/g reduction in MRSA count versus untreated control wounds and a 2.59±0.01 log CFU/g reduction versus baseline counts. For histology analysis, all wounds reached 100% re-epithelialisation by day 5. CONCLUSION: The results of this study indicated that polyvinyl alcohol-based gelling fibre dressing with silver was effective against biofilm of antibiotic-resistant staphylococcal strains without inhibiting the wound healing process, and may have important clinical implications when treating acute and/or hard-to-heal wounds.

Candida albicans Infections: a novel porcine wound model to evaluate treatment efficacy.

Candida albicans is a common cause of opportunistic mycoses worldwide and a major contributor in wound infections. The purpose of this study was to establish a fungal wound model and analyze the effects of a common antifungal agent against the proliferation of three C. albicans strains. Second degree burns were created, and then inoculated with one of three different C. albicans ATCC strains: 10261 reference strain, 64550 fluconazole resistant and 26310 fluconazole sensitive. After fungal inoculation, every wound was covered with dressings for 4 h to allow fungal colonization on every wound bed. After 4 h, the dressings were removed, and each wound was treated either once or twice daily with a topical terbinafine hydrochloride or left untreated. On days 2, 4 and 7 post inoculation, three wounds from each treatment group were scrub cultured and quantified. On day 2, wounds infected with the sensitive strains 26310 and 10261 and treated twice showed a significant reduction when compared against those infected wounds receiving once daily treatment. On day 4, wounds which were infected with C. albicans fluconazole sensitive (ATCC 26310) showed a significant reduction in fungal cell counts with treatment applied twice daily. A significant reduction in the colony counts was exhibited in all three strains at the seventh day with active as compared to the non-treated wounds. Twice daily treatment resulted in a lower fungal count than once daily treatment. Neither treatment was able to entirely eradicate C. albicans during the duration of this study. Establishing a reliable fungal wound model will help in the translational goal of identifying new antifungal that could be used clinically by wound care providers.

Antimicrobial effectiveness of wound matrices containing native extracellular matrix with polyhexamethylene biguanide.

A variety of wound matrix materials that are designed to help heal both acute and chronic wounds are currently available. Because wounds often encounter opportunistic microbes that can delay healing, the effectiveness of these materials is often suboptimal, resulting in delayed or compromised wound healing. The importance of reducing and controlling wound microbes is well recognised and there are several antimicrobial options available to address this unmet clinical need. This study compares the antimicrobial and wound healing capabilities, both in vivo and in vitro against methicillin-resistant Staphylococcus aureus (MRSA) USA 300, for the following compounds: Collagen Wound Matrix-Anti Microbial (CWM-AM); Collagen Wound Matrix-Anti Microbial XT (CWM-AM XT); Antimicrobial Hydrofiber Wound Dressing (AHWD); Dermal Scaffold with Silver (DRSAg); Collagen Extracellular Matrix (CEM); Collagen Wound Matrix (CWM); Matrix Wound Dressing with Silver (MWDAg); Cadexomer Iodine Gel (CIG); Triple Antibiotic Ointment (TAO); and Antimicrobial Wound Gel (AWG). For the in vitro zone of inhibition assay, AWG and CIG had the largest diffused areas, followed by CWM-AM and CWM-AM XT. Furthermore, CWM-AM, CWM-AM XT, AWG, and CIG exhibited a persistent antimicrobial activity for up to 10 days after incubation. However, in the cytotoxicity studies performed using human fibroblasts, CWM-AM and CWM-AM XT had no detrimental effects in cell proliferation and viability, while AWG and CIG were cytotoxic and prohibitive for cell proliferation. Treatments were then assessed for microbiology and wound healing efficacy using an in vivo porcine deep reticular dermal wound model. CWM-AM XT displayed the greatest in vivo antimicrobial activity against MRSA USA300 and expedited the reepithelialisation at a faster rate than other treatment groups. This study shows that a novel collagen matrix containing an antimicrobial agent can reduce the bacterial load and support healing.

Reading Intervention for Students with ASD in the Middle Grades: An Alternating Treatment Study of Embedded Interests Reading and Expository Text Conditions.

AIM: We conducted two separate but related multiple baseline with alternating treatment single-case design studies to investigate the effect of the same reading intervention for students with autism spectrum disorder being implemented under different conditions. METHOD: We conducted a researcher-implemented study in a public school (Study 1) and a teacher-implemented study in a specialized private charter school for children with ASD (Study 2). In each study, we compared a typical intervention approach with interest-based text intervention that included reading on each child's interest area. The treatment included systematic vocabulary instruction and main-summarization strategy instruction. RESULTS: Findings from Study One showed consistent increases in comprehension and vocabulary outcomes compared to baseline. In Study Two the baselines phases were unstable with small differences in mean scores detected for vocabulary during the intervention phase favoring the interest-based treatment for three of four participants. CONCLUSION: The results across studies were mixed indicating the importance of taking into account contextual factors including student characteristics and learning environment.

Effect of Mechanical Debridement and Irrigation With Hypochlorous Acid Wound Management Solution on Methicillin-resistant Staphylococcus aureus Contamination and Healing Deep Dermal Wounds in a Porcine Model.

BACKGROUND: Wound cleansing is an important component of wound management. PURPOSE: This study was conducted to examine the effect of a wound management solution (WMS) containing hypochlorous acid (HOCl) on methicillin-resistant Staphylococcus aureus (MRSA) and healing when used in conjunction with debridement. METHODS: Nineteen (19) deep reticular dermal wounds (22 mm × 22 mm × 3 mm deep) were created on the paravertebral and thoracic areas of 3 female pigs using a specialized electrokeratome. Wounds were separated by at least 5 cm to 7 cm of unwounded skin and inoculated with MRSA. After 72 hours, all wounds were debrided with a curette and irrigated with either the WMS or sterile saline solution twice per day from day 0 to day 4. Wounds then were irrigated once a day until the completion of the study (day 11). Wound tissue specimens were taken using punch biopsy for microbiological and histological analysis on days 4, 8, and 11 post treatment. Percent of wound epithelialized, epithelial thickness (cell layers µm), white cell infiltrate (1 = absent, 2 = mild, 3 = moderate, 4 = marked, 5 = exuberant), and percent of granulation tissue formation were calculated and assessed. Microbiology and histology results were analyzed for significant differences between treatments and among assessment days using one-way analysis of variance and student t-tests. A P value ≤ .05 was considered significant. RESULTS: The WMS effected a bacterial reduction (P ≤ .05) of more than 2.74 ± 0.43 and 1.03 ± 0.22 Log CFU/g in all assessment days compared with baseline before and after debridement, respectively. Percent epithelialization was significantly different between treatments on day 8, only 78.3% and 67.8% for HOCl and saline, respectively (P ≤ .05). No significant differences between treatments were observed for epithelial thickness or granulation tissue formation. CONCLUSION: The combination of debridement and HOCl wound irrigation can significantly reduce MRSA contamination and facilitate the healing process compared to saline irrigation. Clinical studies are needed to confirm these results.

Novel Cyclic Lipopeptides Fusaricidin Analogs for Treating Wound Infections.

Both acute and chronic cutaneous wounds are often difficult to treat due to the high-risk for bacterial contamination. Once hospitalized, open wounds are at a high-risk for developing hospital-associated infections caused by multi drug-resistant bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa. Treating these infections is challenging, not only because of antibiotic resistance, but also due to the production of biofilms. New treatment strategies are needed that will help in both stimulating the wound healing process, as well as preventing and eliminating bacterial wound infections. Fusaricidins are naturally occurring cyclic lipopeptides with antimicrobial properties that have shown to be effective against a variety of fungi and Gram-positive bacteria, with low toxicity. Continuing with our efforts toward the identification of novel cyclic lipopeptides Fusaricidin analogs, herein we report the synthesis and evaluation of the antimicrobial activity for two novel cyclic lipopeptides (CLP), CLP 2605-4 and CLP 2612-8.1 against methicillin resistant S. aureus and P. aeruginosa, respectively, in in vivo porcine full thickness wound model. Both CLPs were able to reduce bacterial counts by approximately 3 log CFU/g by the last assessment day. Peptide 2612-8.1 slightly enhanced the wound healing, however, wounds treated with peptide 2605-4, have shown higher levels of inflammation and impaired wound healing process. This study highlights the importance of identifying new antimicrobials that can combat bacterial infection while not impeding tissue repair.

Reading Instruction for Students with Emotional Disturbance: A Mixed-Methods Investigation.

Although there is a substantial body of observation research investigating the manner in which reading instruction is provided to students with learning disabilities, there is little research in this area involving students with and at risk for emotional disturbance. The purpose of this investigation was to contribute to the limited corpus of observation studies investigating school-based practice in reading for this student population. In this investigation, 11 teachers from two states were systematically observed while providing reading instruction over the course of the 2017-2018 school year. Participating students were also observed over the course of the year and completed two standardized reading assessments at the beginning and end of this investigation. Teachers were also interviewed to identify contextual factors that promote or impede the provision of high quality reading instruction to this student population. Study findings suggest that teachers are in need of additional training, support, and resources to maximize instructional time. Students in this sample tended to make no or minimal progress in reading and were frequently observed displaying low levels of academic engagement across settings. Implications for school practice and areas for future research are discussed.

Vocabulary and Main Idea Reading Intervention Using Text Choice to Improve Content Knowledge and Reading Comprehension of Adolescents With Autism Spectrum Disorder.

This simultaneous replication single-case design study investigated a vocabulary and main idea intervention with an aspect of text choice provided to students with autism spectrum disorder (ASD). Five middle school students with ASD participated in two instructional groups taught by school-based personnel. Results were initially mixed. These results were followed by upward and stable trends, indicating a functional relationship between the independent and dependent variables. Social validity measures indicated that students appreciated the opportunity to make choices on text selection.

Pyruvate-depleting conditions induce biofilm dispersion and enhance the efficacy of antibiotics in killing biofilms in vitro and in vivo.

The formation of biofilms is a developmental process initiated by planktonic cells transitioning to the surface, which comes full circle when cells disperse from the biofilm and transition to the planktonic mode of growth. Considering that pyruvate has been previously demonstrated to be required for the formation of P. aeruginosa biofilms, we asked whether pyruvate likewise contributes to the maintenance of the biofilm structure, with depletion of pyruvate resulting in dispersion. Here, we demonstrate that the enzymatic depletion of pyruvate coincided with the dispersion of established biofilms by S. aureus and laboratory and clinical P. aeruginosa isolates. The dispersion response was dependent on pyruvate fermentation pathway components but independent of proteins previously described to contribute to P. aeruginosa biofilm dispersion. Using porcine second-degree burn wounds infected with P. aeruginosa biofilm cells, we furthermore demonstrated that pyruvate depletion resulted in a reduction of biofilm biomass in vivo. Pyruvate-depleting conditions enhanced the efficacy of tobramycin killing of the resident wound biofilms by up to 5-logs. Our findings strongly suggest the management of pyruvate availability to be a promising strategy to combat biofilm-related infections by two principal pathogens associated with wound and cystic fibrosis lung infections.

Preclinical evaluation of a novel silver gelling fiber dressing on Pseudomonas aeruginosa in a porcine wound infection model.

The wound environment is a fertile ground for biofilm forming pathogens. Once biofilms form within the wound, they can be very challenging to eradicate. The purpose of this study was to examine the effect of a gelling fiber dressing with silver using a well-established porcine wound biofilm model. Deep partial thickness wounds were inoculated with Pseudomonas aeruginosa ATCC 27312 and covered with a polyurethane film dressing to promote biofilm formation. Wounds were then divided into treatment groups: gelling fiber dressing with silver, gelling fiber dressing without silver, hydrofiber dressing with silver, benzethonium chloride and ethylenediaminetetraacetic acid and compared to untreated control. Microbiological, biofilm, and histological wound assessments were performed on days 3, 5, and 7 postinfection. Treatment with gelling fiber dressing with silver resulted in significant reduction of P. aeruginosa biofilm when compared to all other treatment groups on every assessment time point. In addition, gelling fiber dressing with silver treatment resulted in detachment of biofilm from the wound, while wounds treated with gelling fiber dressing with and without silver showed more granulation tissue formation on day 3. Our data show that a new gelling fiber dressing with silver was effective in reducing biofilm associated P. aeruginosa in vivo. This study may have important clinical implications especially for wounds heavily colonized with gram-negative biofilm-forming bacteria.

The Responsible Inclusion of Students Receiving Special Education Services for Emotional Disturbance: Unraveling the Practice to Research Gap.

The majority of students receiving special education services for emotional disturbance (ED) receive a significant amount of instruction in general education classrooms, which emphasizes curriculums based on college and career readiness standards. In turn, those teachers who provide instruction to students with ED in inclusive settings are responsible for using evidence-based practices (EBPs) for those teaching situations in which they exist to meet free appropriate public education (FAPE) mandates. However, the identification of EBPs is a necessary pre-condition to eventual school adoption and teacher use of such practices. In this investigation, we completed a synthesis of syntheses to (a) determine the degree to which academic intervention research has focused on students with ED in general education classrooms and (b) identify practices that are effective at improving the academic performance of students with ED in these settings. Overall, few studies were identified. Of those studies identified, half did not disaggregate outcomes for students with ED. A quality indicator coding based on the What Works Clearinghouse (WWC) design standards revealed that no studies with disaggregated outcomes permitted causal inferences. Implications for school practice and areas for future research are discussed.

Embedding Self-Regulation Into Reading Interventions to Support Reading and Behavior Outcomes.

It was almost winter break, and Ms. Salvador, the reading specialist at Awbrey Park Elementary School, was reviewing the fifth-grade progress-monitoring reading data for students receiving intensive small-group reading interventions. She noticed that several students were not making the reading gains that they had expected. Ms. Salvador and her team also realized that during reading instruction, many of these students displayed problem behaviors, such as having difficulty remaining on task and disrupting other students. After reading as much as she could on the topic, Ms. Salvador found that incorporating self-regulation strategies into reading interventions could lead to improvements in reading and an increase in appropriate behaviors that students display during reading instruction. Knowing how interrelated reading and behavior can be, Ms. Salvador decided to collaborate with Mr. Tanner, the behavior specialist, in developing self-regulation interventions for their students at Awbrey Park Elementary. However, before they could begin to create these self-regulation interventions, Ms. Salvador and Mr. Tanner needed to identify more research on what self-regulation strategies were available and how self-regulation strategies could be used to support students with both reading and behavioral difficulties during small-group reading interventions.

Learning What to Attend to: From the Lab to the Classroom.

Research in adult cognitive neuroscience addresses the bidirectional relationship between attentional selection and prior knowledge gained from learning and experience. This research area is ready for integration with developmental cognitive neuroscience, in particular with educational neuroscience. We review one aspect of this research area, learning what to attend to, to propose a path of integration from highly controlled experiments based on developmental and adult cognitive theories to inform cognitive interventions for learners across the lifespan. In particular, we review the research program that we have developed over the last few years, describe the constraints that we have faced in integrating adult and developmental paradigms, and delineate suggested next steps to inform educational neuroscience in more applied ways. Our proposed path of integration transitions from basic to applied research, while also suggesting that input from education could inform new basic research avenues that may more likely yield outcomes meaningful for education.

The wound-healing effects of a next-generation anti-biofilm silver Hydrofiber wound dressing on deep partial-thickness wounds using a porcine model.

Topical antimicrobials are widely used to control wound bioburden and facilitate wound healing; however, the fine balance between antimicrobial efficacy and non-toxicity must be achieved. This study evaluated whether an anti-biofilm silver-containing wound dressing interfered with the normal healing process in non-contaminated deep partial thickness wounds. In an in-vivo porcine wound model using 2 pigs, 96 wounds were randomly assigned to 1 of 3 dressing groups: anti-biofilm silver Hydrofiber dressing (test), silver Hydrofiber dressing (control), or polyurethane film dressing (control). Wounds were investigated for 8 days, and wound biopsies (n = 4) were taken from each dressing group, per animal, on days 2, 4, 6, and 8 after wounding and evaluated using light microscopy. No statistically significant differences were observed in the rate of reepithelialisation, white blood cell infiltration, angiogenesis, or granulation tissue formation following application of the anti-biofilm silver Hydrofiber dressing versus the 2 control dressings. Overall, epithelial thickness was similar between groups. Some differences in infiltration of specific cell types were observed between groups. There were no signs of tissue necrosis, fibrosis, or fatty infiltration in any group. An anti-biofilm silver Hydrofiber wound dressing did not cause any notable interference with normal healing processes.

Assessment of Ablative Fractional CO2 Laser and Er:YAG Laser to Treat Hypertrophic Scars in a Red Duroc Pig Model.

Hypertrophic scarring is a fibroproliferative process that occurs following a third-degree dermal burn injury, producing significant morbidity due to persistent pain, itching, cosmetic disfigurement, and loss of function due to contractures. Ablative fractional lasers have emerged clinically as a fundamental or standard therapeutic modality for hypertrophic burn scars. Yet the examination of their histopathological and biochemical mechanisms of tissue remodeling and comparison among different laser types has been lacking. In addition, deficiency of a relevant animal model limits our ability to gain a better understanding of hypertrophic scar pathophysiology. To evaluate the effect of ablative fractional lasers on hypertrophic third-degree burn scars, we have developed an in vivo Red Duroc porcine model. Third-degree burn wounds were created on the backs of animals, and burn scars were allowed to develop for 70 days before treatment. Scars received treatment with either CO2 or erbium: yttrium aluminum garnet (YAG) ablative fractional lasers. Here, we describe the effect of both lasers on hypertrophic third-degree burn scars in Red Duroc pigs. In this report, we found that Er:YAG has improved outcomes versus fractional CO2. Molecular changes noted in the areas of dermal remodeling indicated that matrix metalloproteinase 2, matrix metalloproteinase 9, and Decorin may play a role in this dermal remodeling and account for the enhanced effect of the Er:YAG laser. We have demonstrated that ablative fractional laser treatment of burn scars can lead to favorable clinical, histological, and molecular changes. This study provides support that hypertrophic third-degree burn scars can be modified by fractional laser treatment.

The Effects of One versus Two Years of Intensive Reading Intervention Implemented with Late Elementary Struggling Readers.

We examined the effectiveness of a researcher-provided reading intervention with 484 fourth graders with significant reading difficulties. Students were randomly assigned to one year of intervention, two years of intervention, or a business-as-usual comparison condition (BAU). Students assigned to two years of intervention demonstrated significantly greater gains in reading fluency compared to students who received one year of intervention and the BAU group. Students in both the one- and two-year groups demonstrated similar and significantly larger gains in word reading in comparison to the BAU group. There were no statistically significant differences between the three groups on standardized measures of reading comprehension. We discuss these results in the context of research with late elementary and secondary students targeting reading comprehension.

Text-based Vocabulary Intervention Training Study: Supporting Fourth Graders with Low Reading Comprehension and Learning Disabilities.

This experimental study examined the effectiveness of a text-based reading and vocabulary intervention with self-regulatory supports for 4th graders with low reading comprehension. Students with standard scores on the Gates MacGinitie Reading Test between 1.0 standard deviation (SD) and 0.5 SD below the normative sample were included (N=44) and randomly assigned to treatment condition (n=25) or no treatment comparison condition (n=19). Researchers provided the intervention to students in groups of approximately 2-3 students for eight 30 minute sessions. Students in the treatment condition made statistically significant gains on a researcher-developed measure of reading and vocabulary compared with students in the comparison condition.