Sustained release varnish containing chlorhexidine for prevention of Streptococcus mutans biofilm formation on voice prosthesis surface: an in vitro study.

OBJECTIVES: In this study, we aimed to develop a novel, sustained release varnish (SRV) for voice prostheses (VP) releasing chlorhexidine (CHX), for the prevention of biofilm formation caused by the common oral bacteria Streptococcus mutans on VP surfaces. METHODS: This study was performed in an in vitro model as a step towards future in vivo trials. VPs were coated with a SRV containing CHX (SRV-CHX) or SRV alone (placebo-SRV) that were daily exposed to S. mutans. The polymeric materials of SRV were composed of ethylcellulose and PEG-400. Biofilm formation was assessed by DNA quantification (qPCR), crystal violet staining, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and kinetics experiments. RESULTS: The amount of DNA in the biofilms formed by S. mutans on VP surfaces coated once with SRV-CHX (1.024 ± 0.218 ng DNA/piece) was 58.5 ± 8.8% lower than that of placebo-SRV-coated VPs (2.465 ± 0.198 ng DNA/piece) after a 48-h exposure to S. mutans (p = 0.038). Reduced biofilm mass on SRV-CHX-coated VPs was visually confirmed by CLSM and SEM. CV staining of SRV-CHX single-coated VPs that have been exposed to S. mutans nine times showed a 98.1 ± 0.2% reduction in biofilm mass compared to placebo-SRV-coated VPs (p = 0.003). Kinetic experiments revealed that SRV-CHX triple-coated VPs could delay bacterial growth for 23 days. CONCLUSIONS: Coating VPs with SRV-CHX has an inhibitory effect on biofilm formation and prevents bacterial growth in their vicinities. This study is a proof-of-principle that paves the way for developing new clinical means for reducing both VPs' bacterial biofilm formation and device failure.

Anti-Bacterial Effect of Cannabidiol against the Cariogenic Streptococcus mutans Bacterium: An In Vitro Study.

Dental caries is caused by biofilm-forming acidogenic bacteria, especially Streptococcus mutans, and is still one of the most prevalent human bacterial diseases. The potential use of cannabidiol (CBD) in anti-bacterial therapies has recently emerged. Here we have studied the anti-bacterial and anti-biofilm activity of CBD against S. mutans. We measured minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC). The bacterial growth and changes in pH values were measured in a kinetic study. The biofilm biomass was assessed by Crystal Violet staining and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) metabolic assay. Spinning Disk Confocal Microscopy (SDCM) was used to assess biofilm structure, bacterial viability and extracellular polysaccharide (EPS) production. CBD inhibited S. mutans planktonic growth and biofilm formation in a dose-dependent manner, with similar MIC and MBIC values (5 µg/mL). CBD prevented the bacteria-mediated reduction in pH values that correlated with bacterial growth inhibition. SDCM showed a decrease of 50-fold in live bacteria and EPS production. CBD significantly reduced the viability of preformed biofilms at 7.5 µg/mL with an 80 ± 3.1% reduction of metabolic activity. At concentrations above 20 µg/mL, there was almost no bacterial recovery in the CBD-treated preformed biofilms even 48 h after drug withdrawal. Notably, precoating of the culture plate surfaces with CBD prior to incubation with bacteria inhibited biofilm development. Additionally, CBD was found to induce membrane hyperpolarization in S. mutans. Thus, CBD affects multiple processes in S. mutans including its cariogenic properties. In conclusion, we show that CBD has a strong inhibitory effect against cariogenic bacteria, suggesting that it is a potential drug adjuvant for reducing oral pathogenic bacterial load as well as protecting against dental caries.

Mechanism by which immune complexes are deposited in hosts tissue.

We offer an explanation how immune complexes are deposited in tissues of auto-immune disorders in humans. These disorders are characterized by the accumulation in tissues of large numbers of neutrophils, which can shed out long extracellular traps (NETs) rich in a nucleosome and in highly opsonic poly cations, histone, LL37, defensins and elastase possessing properties similar to antibodies. These can bind by strong electrostatic forces to negatively charged domains in immune globulins, thus facilitating their deposition and internalization by tissue cells. However, the main cause for tissue damage in auto-immune patients is inflicted by the plethora of toxic pro-inflammatory agents released by activated neutrophils. To ameliorate tissue damage and the cytokine storms, it is recommended to administer to patients highly anionic heparins accompanied by steroids, methotrexate, colchicine, copaxone, and also by additional agents which retarded neutrophil functions.

To sim or not to sim-choosing wisely for procedural skills training in paediatrics.

Objectives: Simulation is a commonly used modality to teach paediatric procedural skills, however, it is resource intensive. Which paediatric skills are best taught using simulation is not known. This study aims to examine what skills to simulate, allowing for the best use of resources in ever expanding curricula. Method: We administered a questionnaire to community and hospitalist general paediatricians in Canada asking them to rate the importance of maintaining competency in each paediatric procedural skill and the frequency with which they perform the skill in their practice. Results: Skills that were rated as highly important and also high frequency were: bag-mask ventilation (BMV), lumbar puncture, neonatal cardiopulmonary resuscitation (CPR), specimen procurement for infectious diseases, immunization, and ear curettage. Skills that were rated as highly important but low frequency were: paediatric CPR, intraosseous needle insertion, neonatal intubation, defibrillation, gathering specimens for evidence of child maltreatment, paediatric intubation, cervical spine immobilization, and oral/nasogastric tube placement. Conclusion: Paediatric procedural skills are rated variably in terms of importance and frequency of use in general paediatric practice. Eight skills of high importance are infrequently performed and should be targeted for teaching via simulation.

Assessing nephrology competence in general paediatrics-A survey of general paediatricians, paediatric nephrologists, residents, and program directors.

Objective: The objective of this study was to identify nephrology topics of lowest perceived competency and importance for general paediatricians. Methods: Surveys were distributed to general paediatricians, paediatric residents, paediatric residency program directors, and paediatric nephrologists. Perceived importance and competence were rated on a 5-point Likert scale. Means and 95% confidence intervals were calculated. Results: Mean perceived competency from general paediatricians across all nephrology domains was 3.0, 95%CI (2.9 to 3.1) and mean importance was 3.2, 95%CI (3.1 to 3.3). Domains scoring below the means for competence and importance, respectively were kidney stones (2.5, 95%CI [2.2 to 2.7]) and 2.6, 95%CI [2.3 to 2.8]), acute kidney injury (2.5, 95%CI [2.2 to 2.8] and 2.4, 95%CI [2.1 to 2.8]), chronic kidney disease (1.9, 95%CI [1.7 to 2.2] and 2.1, 95%CI [1.8 to 2.4]), tubular disorders (1.8, 95%CI [1.6 to 2.0] and 2.0, 95%CI [1.8 to 2.3]), and kidney transplant (1.6, 95%CI [1.4 to 1.8] and 1.7, 95%CI [1.4 to 1.9]). Residents, program directors, and paediatric nephrologists agreed that stones, chronic kidney disease, tubular disorders, and transplant were of lower importance. However, acute kidney injury was the domain with the largest discrepancy in perceived importance between residents (4.4, 95%CI [4.2 to 4.6]), nephrologists (4.2, 95%CI [3.8 to 4.6]), and program directors (4.2, 95%CI [3.7 to 4.7]) compared to general paediatricians ([2.4, 95%CI [2.1 to 2.8]; P<0.05). Conclusion: Paediatricians did not believe acute kidney injury was important to their practice, despite expert opinion and evidence of long-term consequences. Educational interventions must address deficits in crucial domains of renal health in paediatrics.

Pre-Endoscopy Use of Proton Pump Inhibitor Intravenous Bolus Dosing in Hemodynamically Stable Patients With Suspected Upper Gastrointestinal Bleeding: Results of a Pharmacist-Managed Hospital Protocol to Reduce Continuous Infusion Pantoprazole Use.

Background: Guidelines for acute upper gastrointestinal bleeding (UGIB) recommend use of proton pump inhibitors (PPI) administered by continuous IV infusion (CI). Although data suggest comparable outcomes with CI and IV push (IVP) dosing post-endoscopy, there are limited data to support IVP PPI as the pre-endoscopy regimen. Objective: To evaluate the impact of a pharmacist-managed protocol for reducing PPI CIs and substitution of PPI IVP dosing in hemodynamically stable patients with suspected acute upper gastrointestinal bleeding (UGIB) prior to endoscopic intervention. Design, Setting, and Participants: Retrospective study; Tertiary-care community teaching hospital; Hemodynamically stable adults with confirmed or suspected UGIB. Hemodynamic stability was defined as a systolic blood pressure >90 mmHg, heart rate <100 beats, mean arterial pressure >65 mmHg, and no requirement for vasopressors. Intervention: All iterations of treatment recommendations encouraged an initial pantoprazole 80 mg IVP dose. In the pre-intervention group, patients were then treated at the at the provider's discretion with the majority receiving CI pantoprazole. After implementation of the original protocol (Phase I), all hemodynamically stable patients were allowed 1 bag of CI pantoprazole (80 mg infused over 10 hours) before being transitioned by the pharmacist to pantoprazole 40 mg IVP every 12 hours. After internal analysis, the protocol was revised to allow patients to be immediately transitioned to IVP dosing without an initial CI (Phase II). Main Outcome: Incidence of continued bleeding or re-bleeding within 7 days of initial PPI dose. Results: A total of 325 patients were included across all 3 study phases. The median number of CI bags per patient was reduced from 4 pre-intervention, to 1.5 in phase I, and to 0 in phase II (P < .001). The primary endpoint of continued bleeding or re-bleeding within 7 days was similar across all 3 groups (5.0% vs 6.5% vs 5.2%, P = .92). Mean intravenous pantoprazole costs were reduced by $21.73/patient. Conclusions: Movement toward preferential use of IVP PPI prior to endoscopy for hemodynamically stable patients with confirmed or suspected UGIBs resulted in similar rates of continued bleeding or re-bleeding and generated modest cost savings. These findings warrant further investigation.

Clinical Laboratory Perspective on Streptococcus halichoeri, an Unusual Nonhemolytic, Lancefield Group B Streptococcus Causing Human Infections.

Streptococcus halichoeri is a relatively newly identified species of pyogenic streptococci that causes zoonotic infection in humans. S. halichoeri was first described in 2004 as indigenous to seals, and only 8 reports of human S. halichoeri infection have been published. S. halichoeri grows as small, white, nonhemolytic colonies and may be strongly catalase-positive on routine blood agar media, which can lead to isolates being misidentified as coagulase-negative staphylococci. S. halichoeri tests positive for Lancefield group B antigen, like S. agalactiae, but can be identified with matrix-assisted laser desorption/ionization time of flight mass spectrometry or partial 16S rRNA sequencing. We describe 3 cases of S. halichoeri bone and joint infections in patients in the United States with underlying health conditions. In addition, we examine the microbiologic characteristics of S. halichoeri and discuss the importance of fully identifying this organism that might otherwise be disregarded as a skin commensal.

ADHD in children and youth: Part 2-Treatment.

Attention-deficit hyperactivity disorder (ADHD) is a chronic neurodevelopmental disorder. Three position statements have been developed by the Canadian Paediatric Society, following systematic literature reviews. Statement objectives are to: 1) Summarize the current clinical evidence regarding ADHD,2) Establish a standard for ADHD care, and3) Assist Canadian clinicians in making well-informed, evidence-based decisions to enhance care of children and youth with this condition. Specific topics reviewed in Part 2, which focuses on treatment, include: evidence and context for a range of clinical approaches, combining behavioural and pharmacological interventions to address impairment more effectively, the role of parent and teacher (or other caregiver) training, the use of stimulant and nonstimulant medications, with effects and risks, and dosing and monitoring protocols. Treatment recommendations are based on current guidelines, evidence from the literature, and expert consensus.

Cationic Pillararenes Potently Inhibit Biofilm Formation without Affecting Bacterial Growth and Viability.

It is estimated that up to 80% of bacterial infections are accompanied by biofilm formation. Since bacteria in biofilms are less susceptible to antibiotics than are bacteria in the planktonic state, biofilm-associated infections pose a major health threat, and there is a pressing need for antibiofilm agents. Here we report that water-soluble cationic pillararenes differing in the quaternary ammonium groups efficiently inhibited the formation of biofilms by clinically important Gram-positive pathogens. Biofilm inhibition did not result from antimicrobial activity; thus, the compounds should not inhibit growth of natural bacterial flora. Moreover, none of the cationic pillararenes caused detectable membrane damage to red blood cells or toxicity to human cells in culture. The results indicate that cationic pillararenes have potential for use in medical applications in which biofilm formation is a problem.

Characteristics and Clinical Management of a Cluster of 3 Patients With Ebola Virus Disease, Including the First Domestically Acquired Cases in the United States.

BACKGROUND: More than 26,000 cases of Ebola virus disease (EVD) have been reported in western Africa, with high mortality. Several patients have been medically evacuated to hospitals in the United States and Europe. Detailed clinical data are limited on the clinical course and management of patients with EVD outside western Africa. OBJECTIVE: To describe the clinical characteristics and management of a cluster of patients with EVD, including the first cases of Ebola virus (EBOV) infection acquired in the United States. DESIGN: Retrospective clinical case series. SETTING: Three U.S. hospitals in September and October 2014. PATIENTS: First imported EVD case identified in the United States and 2 secondary EVD cases acquired in the United States in critical care nurses who cared for the index case patient. MEASUREMENTS: Clinical recovery, EBOV RNA level, resolution of Ebola viremia, survival with discharge from hospital, or death. RESULTS: The index patient had high EBOV RNA levels, developed respiratory and renal failure requiring critical care support, and died. Both patients with secondary EBOV infection had nonspecific signs and symptoms and developed moderate illness; EBOV RNA levels were moderate, and both patients recovered. LIMITATION: Both surviving patients received uncontrolled treatment with multiple investigational agents, including convalescent plasma, which limits generalizability of the results. CONCLUSION: Early diagnosis, prompt initiation of supportive medical care, and moderate clinical illness likely contributed to successful outcomes in both survivors. The inability to determine the potential benefit of investigational therapies and the effect of patient-specific factors that may have contributed to less severe illness highlight the need for controlled clinical studies of these interventions, especially in the setting of a high level of supportive medical care. PRIMARY FUNDING SOURCE: None.

Sustained release of a novel anti-quorum-sensing agent against oral fungal biofilms.

Thiazolidinedione-8 (S-8) has recently been identified as a potential anti-quorum-sensing/antibiofilm agent against bacteria and fungi. Based on these results, we investigated the possibility of incorporating S-8 in a sustained-release membrane (SRM) to increase its pharmaceutical potential against Candida albicans biofilm. We demonstrated that SRM containing S-8 inhibits fungal biofilm formation in a time-dependent manner for 72 h, due to prolonged release of S-8. Moreover, the SRM effectively delivered the agent in its active form to locations outside the membrane reservoir. In addition, eradication of mature biofilm by the SRM containing S-8 was also significant. Of note, S-8-containing SRM affected the characteristics of mature C. albicans biofilm, such as thickness, exopolysaccharide (EPS) production, and morphogenesis of fungal cells. The concept of using an antibiofilm agent with no antifungal activity incorporated into a sustained-release delivery system is new in medicine and dentistry. This concept of an SRM containing a quorum-sensing quencher with an antibiofilm effect could pave the way for combating oral fungal infectious diseases.

Critical Care for Multiple Organ Failure Secondary to Ebola Virus Disease in the United States.

OBJECTIVE: This report describes three patients with Ebola virus disease who were treated in the United States and developed for severe critical illness and multiple organ failure secondary to Ebola virus infection. The patients received mechanical ventilation, renal replacement therapy, invasive monitoring, vasopressor support, and investigational therapies for Ebola virus disease. DATA SOURCES: Patient medical records from three tertiary care centers (Emory University Hospital, University of Nebraska Medical Center, and Texas Health Presbyterian Dallas Hospital). STUDY SELECTION: Not applicable. DATA EXTRACTION: Not applicable. DATA SYNTHESIS: Not applicable. CONCLUSION: In the severe form, patients with Ebola virus disease may require life-sustaining therapy, including mechanical ventilation and renal replacement therapy. In conjunction with other reported cases, this series suggests that respiratory and renal failure may occur in severe Ebola virus disease, especially in patients burdened with high viral loads. Ebola virus disease complicated by multiple organ failure can be survivable with the application of advanced life support measures. This collective, multicenter experience is presented with the hope that it may inform future treatment of patients with Ebola virus disease requiring critical care treatment.

Tobramycin and nebramine as pseudo-oligosaccharide scaffolds for the development of antimicrobial cationic amphiphiles.

Antimicrobial cationic amphiphiles derived from aminoglycoside pseudo-oligosaccharide antibiotics interfere with the structure and function of bacterial membranes and offer a promising direction for the development of novel antibiotics. Herein, we report the design and synthesis of cationic amphiphiles derived from the pseudo-trisaccharide aminoglycoside tobramycin and its pseudo-disaccharide segment nebramine. Antimicrobial activity, membrane selectivity, mode of action, and structure-activity relationships were studied. Several cationic amphiphiles showed marked antimicrobial activity, and one amphiphilic nebramine derivative proved effective against all of the tested strains of bacteria; furthermore, against several of the tested strains, this compound was well over an order of magnitude more potent than the parent antibiotic tobramycin, the membrane-targeting antimicrobial peptide mixture gramicidin D, and the cationic lipopeptide polymyxin B, which are in clinical use.

Deletion of 15q11.2(BP1-BP2) region: further evidence for lack of phenotypic specificity in a pediatric population.

Microdeletion of the BP1-BP2 region at 15q11.2 is a recurrent copy number variant (CNV) frequently found in patients undergoing chromosomal microarray (CMA). Genetic counselling regarding this CNV is challenging due to the wide range of phenotypic presentation in reported patients and lack of general population-based data. As one of the most common reasons for CMA is childhood developmental delay, clinicians need to be cognizant of the inherent ascertainment bias in the literature. We performed a detailed medical record review for 55 patients with this 15q11.2 microdeletion and report the clinical features of the 35 patients for whom information was available. We compared our results to the recent report by Cafferkey et al. in this journal. Our conclusion is that the phenotypic spectrum is too broad and non-specific to constitute a bona fide "syndrome" and that further research must be done to delineate the contribution of this CNV to phenotype.

Canadian guidelines on pharmacotherapy for disruptive and aggressive behaviour in children and adolescents with attention-deficit hyperactivity disorder, oppositional defiant disorder, or conduct disorder.

OBJECTIVE: To develop evidence-based guidelines on pharmacotherapy for severe disruptive and aggressive behaviour in children and adolescents with attention-deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), or conduct disorder (CD). The guidelines assume that psychosocial interventions have been pursued but did not achieve sufficient improvement. METHOD: A multidisciplinary consensus group used the Grading of Recommendations Assessment, Development and Evaluation approach for rating evidence quality and for grading recommendations. We conducted a systematic review of medications studied in placebo-controlled trials for treating disruptive and aggressive behaviour in children and adolescents with ADHD, ODD, or CD. We followed consensus procedures to make 1 of 4 recommendations for each medication: strong, in favour (↑↑); conditional, in favour (↑?); conditional, against (↓?); and strong, against (↓↓). RESULTS: For children and adolescents with disruptive or aggressive behaviour associated with ADHD, psychostimulants received a strong recommendation in favour of use, while atomoxetine and alpha-2 agonists received a conditional recommendation in favour of use. If these patients do poorly with ADHD medications, the medication with the most evidence is risperidone. Risperidone also has the most evidence for treating disruptive or aggressive behaviour in the absence of ADHD. However, given risperidone's major adverse effects, it received only a conditional recommendation in favour of use. We recommended against using quetiapine, haloperidol, lithium, or carbamazepine because of the poor quality of evidence and their major adverse effects. CONCLUSION: When severe disruptive or aggressive behaviour occurs with ADHD, medications for ADHD should be used first. Other medications have major adverse effects and, with the exception of risperidone, very limited evidence to support their use.

Gastroenterology's editors-in-chief: historical and personal perspectives of their editorships.

Fourteen editors-in-chiefs have steered Gastroenterologyto success since its inception in 1943. Five (Alvarez, Ivy, Aaron, Grossman, and Donaldson) are no longer with us. Their personalities and editorships, along with those of Marvin Sleisenger, are presented by their admirers. Fordtran, Ockner, Goyal, LaRusso, Podolsky, Brenner, Rustgi, and Omary describe their own backgrounds, experiences, and personal reflections on serving as editor-in-chief of Gastroenterology.

J. Edward Berk Distinguished [corrected] lecture: Gastric acid secretion: still relevant?

Serious, life-threatening conditions may result from too much gastric acid secretion by parietal cells, too little secretion of gastric acid and intrinsic factor by parietal cells, or loss of secreted gastric hydrochloric acid from the body. Understanding the physiology and pathophysiology of gastric secretion and its regulation can improve patient care and clinical outcomes. Gastric secretion remains highly relevant to practicing clinicians.

Di-alkylated paromomycin derivatives: targeting the membranes of gram positive pathogens that cause skin infections.

A collection of paromomycin-based di-alkylated cationic amphiphiles differing in the lengths of their aliphatic chain residues were designed, synthesized, and evaluated against 14 Gram positive pathogens that are known to cause skin infections. Paromomycin derivatives that were di-alkylated with C7 and C8 linear aliphatic chains had improved antimicrobial activities relative to the parent aminoglycoside as well as to the clinically used membrane-targeting antibiotic gramicidin D; several novel derivatives were at least 16-fold more potent than the parent aminoglycoside paromomycin. Comparison between a di-alkylated and a mono-alkylated paromomycin indicated that the di-alkylation strategy leads to both an improvement in antimicrobial activity and to a dramatic reduction in undesired red blood cell hemolysis caused by many aminoglycoside-based cationic amphiphiles. Scanning electron microscopy provided evidence for cell surface damage by the reported di-alkylated paromomycins.

Improved Anti-Biofilm Effect against the Oral Cariogenic Streptococcus mutans by Combined Triclosan/CBD Treatment.

Streptococcus mutans is a Gram-positive bacterium highly associated with dental caries, and it has a strong biofilm-forming ability, especially in a sugar-rich environment. Many strategies have been undertaken to prevent dental caries by targeting these bacteria. Recently, we observed that a sustained-release varnish containing triclosan and cannabidiol (CBD) was more efficient than each compound alone in preventing biofilm formation by the fungus Candida albicans, which is frequently involved in oral infections together with S. mutans. It was therefore inquiring to study the effect of this drug combination on S. mutans. We observed that the combined treatment of triclosan and CBD had stronger anti-bacterial and anti-biofilm activity than each compound alone, thus enabling the use of lower concentrations of each drug to achieve the desired effect. The combined drug treatment led to an increase in the SYTO 9low, propidium iodide (PI)high bacterial population as analyzed by flow cytometry, indicative for bacteria with disrupted membrane. Both triclosan and CBD induced membrane hyperpolarization, although there was no additive effect on this parameter. HR-SEM images of CBD-treated bacteria show the appearance of elongated and swollen bacteria with several irregular septa structures, and upon combined treatment with triclosan, the bacteria took on a swollen ellipse and sometimes oval morphology. Increased biofilm formation was observed at sub-MIC concentrations of each compound alone, while combining the drugs at these sub-MIC concentrations, the biofilm formation was prevented. The inhibition of biofilm formation was confirmed by CV biomass staining, MTT metabolic activity, HR-SEM and live/dead together with exopolysaccharide (EPS) staining visualized by spinning disk confocal microscopy. Importantly, the concentrations required for the anti-bacterial and anti-biofilm activities toward S. mutans were non-toxic to the normal Vero epithelial cells. In conclusion, the data obtained in this study propose a beneficial role of combined triclosan/CBD treatment for potential protection against dental caries.

Multiple coinfections and Guillain Barré syndrome following outdoor travel to the American Northeast.

A 66-year-old immunocompetent man with preceding travel through the Northeastern United States developed Guillain-Barré syndrome. A broad search for infections revealed intraerythrocytic parasites on blood smear and positive polymerase chain reaction for Babesia microti; elevated IgM/IgG serologies for Ehrlichia chaffeensis; elevated IgM/IgG serologies and qualitative polymerase chain reaction for Epstein-Barr virus; and fecal culture growth of Arcobacter butzleri. In this report, we discuss the known or suspected association of these infectious agents with Guillain-Barré syndrome. This case also highlights the importance, in the setting of endemic exposure, of screening for multiple coinfections that can be transmitted by the same arthropod vector.