Informed development of a multi-species biofilm in chronic obstructive pulmonary disease

Recent evidence indicates that microbial biofilm aggregates inhabit the lungs of COPD patients and actively contribute towards chronic colonization and repeat infections. However, there are no contextually relevant complex biofilm models for COPD research. In this study, a meta-analysis of the lung microbiome in COPD was used to inform development of an optimized biofilm model composed of genera highly associated with COPD. Bioinformatic analysis showed that although diversity matrices of COPD microbiomes were similar to healthy controls, and internal compositions made it possible to accurately differentiate between these cohorts (AUC = 0.939). Genera that best defined these patients included Haemophilus, Moraxella and Streptococcus. Many studies fail to account for fungi; therefore, Candida albicans was included in the creation of an interkingdom biofilm model. These organisms formed a biofilm capable of tolerating high concentrations of antimicrobial therapies with no significant reductions in viability. However, combined therapies of antibiotics and an antifungal resulted in significant reductions in viable cells throughout the biofilm (p < 0.05). This biofilm model is representative of the COPD lung microbiome and results from in vitro antimicrobial challenge experiments indicate that targeting both bacteria and fungi in these interkingdom communities will be required for more positive clinical outcomes.

Dose-dependent effects of enteral nutrition on the faecal microbiota and short chain fatty acids

INTRODUCTION

Enteral nutrition (EN) involves replacing all or part of a person's habitual diet with a nutritional formula. The impact of varying doses of EN on the gut microbiome remains understudied.

METHODS

Healthy adults replaced all (100% EN) or part (85% EN, 50% EN and 20% EN) of their energy requirements with EN for 7 days. Faecal samples were collected before and on day 7 of interventions. Faecal pH, short chain fatty acids (SCFAs), branched-chain fatty acids (BCFAs) and 16S rRNA sequencing were performed. Dietary assessment was performed with 7-day food diaries.

RESULTS

Sixty-one participants (31 females; median (IQR) age: 24.7 (23.0-27.8) years) were recruited. A dose-dependent impact of EN on faecal microbiota, SCFAs, BCFAs) and pH was observed, with changes detectable at EN intakes of at least 50% of energy requirements. 100% and 85% EN reduced the abundance of fibre-fermenting taxa such as Agathobacter, Faecalibaterium, Succinivibrio and Acidaminococcus. In parallel, potentially harmful organisms like Eubacterium, Actinomyces, and Klebsiella increased. In the 50% EN group, adherence to a diet high in fish, vegetables, potatoes, non-alcoholic beverages, and fat spreads, and low in cereal products, milk, and meat negatively correlated with changes in microbiota structure (r = -0.75, P = 0.025). This signal was not observed when using compositional tools for microbiota analysis.

CONCLUSIONS

EN detrimentally influences the faecal microbiota and diet-related bacterial metabolites in a dose-dependent manner, particularly at doses of at least 50%. The findings of this study have implications for the dietary management and counselling of patients receiving high volume EN.

A quality improvement strategy to reduce unintended extubation in the very low birth weight infant-A case report

BACKGROUND

Unintended extubations remain a common complication across neonatal intensive care units, with very low birthweight infants being the most vulnerable of them all. Ongoing efforts across different institutions exist with the goal of reducing the rate of unintended extubations to keep a median rate of <2 events per 100 ventilator days as defined by the Vermont Oxford Network. Our objective was to reduce unintended extubations in the very low birthweight infant in a large delivery hospital to ≤2/100 ventilator days.

METHODS

A collaborative group was formed between two academic health institutions targeting training and implementation of the Children's National unintended extubation system, focusing on endotracheal tube securement methods and surveillance protocols.

RESULTS

The unintended extubation rate decreased from 3.23 to 0.64 per 100 ventilator days. Changes were implemented from 2018-2020 with a sustained reduction in the unintended extubation rate of 1.54 per 100 ventilator days. Most events occurred between 12 : 00 pm -4 : 00 pm and the commonest cause was spontaneous (25%) followed by dislodgment during repositioning (19%).

CONCLUSION

Very low birth weight infants present a challenge to endotracheal tube maintenance due to their developmental and anatomical changes during their neonatal intensive care unit stay. Successful reduction of unintended extubations in the very low birthweight infant can be achieved by adaptation of successful protocols for older infants.

Investigating the chemical pathway to the formation of a single biofilm using infrared spectroscopy

Diagnosing biofilm infections has remained a constant challenge for the last 50 years. Existing diagnostic methods struggle to identify the biofilm phenotype. Moreover, most methods of biofilm analysis destroy the biofilm making the resultant data interpretation difficult. In this study we introduce Fourier Transform Infra-Red (FTIR) spectroscopy as a label-free, non-destructive approach to monitoring biofilm progression. We have utilised FTIR in a novel application to evaluate the chemical composition of bacterial biofilms without disrupting the biofilm architecture. S. epidermidis (RP62A) was grown onto calcium fluoride slides for periods of 30 min-96 h, before semi-drying samples for analysis. We report the discovery of a chemical marker to distinguish between planktonic and biofilm samples. The appearance of new proteins in biofilm samples of varying maturity is exemplified in the spectroscopic data, highlighting the potential of FTIR for identifying the presence and developmental stage of a single biofilm.

Staphylococcus aureus strains exhibit heterogenous tolerance to direct cold atmospheric plasma therapy

The global clinical and socioeconomic impact of chronic wounds is substantial. The main difficulty that clinicians face during the treatment of chronic wounds is the risk of infection at the wound site. Infected wounds arise from an accumulation of microbial aggregates in the wound bed, leading to the formation of polymicrobial biofilms that can be largely resistant to antibiotic therapy. Therefore, it is essential for studies to identify novel therapeutics to alleviate biofilm infections. One innovative technique is the use of cold atmospheric plasma (CAP) which has been shown to possess promising antimicrobial and immunomodulatory properties. Here, different clinically relevant biofilm models will be treated with cold atmospheric plasma to assess its efficacy and killing effects. Biofilm viability was assessed using live dead qPCR, and morphological changes associated with CAP evaluated using scanning electron microscopy (SEM). Results indicated that CAP was effective against Candida albicans and Pseudomonas aeruginosa, both as mono-species biofilms and when grown in a triadic model system. CAP also significantly reduced viability in the nosocomial pathogen, Candida auris. Staphylococcus aureus Newman exhibited a level of tolerance to CAP therapy, both when grown alone or in the triadic model when grown alongside C. albicans and P. aeruginosa. However, this degree of tolerance exhibited by S. aureus was strain dependent. At a microscopic level, biofilm treatment led to subtle changes in morphology in the susceptible biofilms, with evidence of cellular deflation and shrinkage. Taken together, these results indicate a promising application of direct CAP therapy in combatting wound and skin-related biofilm infections, although biofilm composition may affect the treatment efficacy.

Investigating the role of Candida albicans as a universal substrate for oral bacteria using a transcriptomic approach: implications for interkingdom biofilm control?

Candida albicans is frequently identified as a colonizer of the oral cavity in health and has recently been termed a "keystone" commensal due to its role on the bacterial communities. However, the role that C. albicans plays in such interactions is not fully understood. Therefore, this study aimed to identify the relationship between C. albicans and bacteria associated with oral symbiosis and dysbiosis. To do this, we evaluated the ability of C. albicans to support the growth of the aerobic commensal Streptococcus gordonii and the anaerobic pathogens Fusobacterium nucleatum and Porphyromonas gingivalis in the biofilm environment. RNA-Sequencing with the Illumina platform was then utilized to identify C. albicans gene expression and functional pathways involved during such interactions in dual-species and a 4-species biofilm model. Results indicated that C. albicans was capable of supporting growth of all three bacteria, with a significant increase in colony counts of each bacteria in the dual-species biofilm (p < 0.05). We identified specific functional enrichment of pathways in our 4-species community as well as transcriptional profiles unique to the F. nucleatum and S. gordonii dual-species biofilms, indicating a species-specific effect on C. albicans. Candida-related hemin acquisition and heat shock protein mediated processes were unique to the organism following co-culture with anaerobic and aerobic bacteria, respectively, suggestive that such pathways may be feasible options for therapeutic targeting to interfere with these fungal-bacterial interactions. Targeted antifungal therapy may be considered as an option for biofilm destabilization and treatment of complex communities. Moving forward, we propose that further studies must continue to investigate the role of this fungal organism in the context of the interkingdom nature of oral diseases.

Cold Atmospheric Plasma-Activated Composite Hydrogel for an Enhanced and On-Demand Delivery of Antimicrobials

We present the concept of a versatile drug-loaded composite hydrogel that can be activated using an argon-based cold atmospheric plasma (CAP) jet to deliver both a drug and CAP-generated molecules, concomitantly, in a tissue target. To demonstrate this concept, we utilized the antibiotic gentamicin that is encapsulated in sodium polyacrylate (PAA) particles, which are dispersed within a poly(vinyl alcohol) (PVA) hydrogel matrix. The final product is a gentamicin-PAA-PVA composite hydrogel suitable for an on-demand triggered release using CAP. We show that by activating using CAP, we can effectively release gentamicin from the hydrogel and also eradicate the bacteria effectively, both in the planktonic state and within a biofilm. Besides gentamicin, we also successfully demonstrate the applicability of the CAP-activated composite hydrogel loaded with other antimicrobial agents such as cetrimide and silver. This concept of a composite hydrogel is potentially adaptable to a range of therapeutics (such as antimicrobials, anticancer agents, and nanoparticles) and activatable using any dielectric barrier discharge CAP device.

An integrated transcriptomic and metabolomic approach to investigate the heterogeneous Candida albicans biofilm phenotype

Candida albicans is the most prevalent and notorious of the Candida species involved in bloodstream infections, which is characterised by its capacity to form robust biofilms. Biofilm formation is an important clinical entity shown to be highly variable among clinical isolates. There are various environmental and physiological factors, including nutrient availability which influence the phenotype of Candida species. However, mechanisms underpinning adaptive biofilm heterogeneity have not yet been fully explored. Within this study we have profiled previously characterised and phenotypically distinct C. albicans bloodstream isolates. We assessed the dynamic susceptibility of these differing populations to antifungal treatments using population analysis profiling in addition to assessing biofilm formation and morphological changes. High throughput methodologies of RNA-Seq and LC-MS were employed to map and integrate the transcriptional and metabolic reprogramming undertaken by heterogenous C. albicans isolates in response to biofilm and hyphal inducing serum. We found a significant relationship between biofilm heterogeneity and azole resistance (P < 0.05). In addition, we observed that in response to serum our low biofilm forming (LBF) C. albicans exhibited a significant increase in biofilm formation and hyphal elongation. The transcriptional reprogramming of LBF strains compared to high biofilm forming (HBF) was distinct, indicating a high level of plasticity and variation in stress responses by heterogenous strains. The metabolic responses, although variable between LBF and HBF, shared many of the same responses to serum. Notably, a high upregulation of the arachidonic acid cascade, part of the COX pathway, was observed and this pathway was found to induce biofilm formation in LBF 3-fold. C. albicans is a highly heterogenous bloodstream pathogen with clinical isolates varying in antifungal tolerance and biofilm formation. In addition to this, C. albicans is capable of highly complex and variable regulation of transcription and metabolic pathways and heterogeneity across isolates further increases the complexity of these pathways. Here we have shown with a dual and integrated approach, the importance of studying a diverse panel of C. albicans isolates, which has the potential to reveal distinct pathways that can harnessed for drug discovery.

Meta-analysis of caries microbiome studies can improve upon disease prediction outcomes

As one of the most prevalent infective diseases worldwide, it is crucial that we not only know the constituents of the oral microbiome in dental caries but also understand its functionality. Herein, we present a reproducible meta-analysis to effectively report the key components and the associated functional signature of the oral microbiome in dental caries. Publicly available sequencing data were downloaded from online repositories and subjected to a standardized analysis pipeline before analysis. Meta-analyses identified significant differences in alpha and beta diversities of carious microbiomes when compared to healthy ones. Additionally, machine learning and receiver operator characteristic analysis showed an ability to discriminate between healthy and disease microbiomes. We identified from importance values, as derived from random forest analyses, a group of genera, notably containing Selenomonas, Aggregatibacter, Actinomyces and Treponema, which can be predictive of dental caries. Finally, we propose the most appropriate study design for investigating the microbiome of dental caries by synthesizing the studies, which had the most accurate differentiation based on random forest modelling. In conclusion, we have developed a non-biased, reproducible pipeline, which can be applied to microbiome meta-analyses of multiple diseases, but importantly we have derived from our meta-analysis a key group of organisms that can be used to identify individuals at risk of developing dental caries based on oral microbiome inhabitants.

Cell Viability Assays for Candida auris

Cell viability assays are useful for assessing the efficacy of antifungal therapeutics and disinfection strategies in vitro. In recent years these assays have been fundamental for the testing of conventional and novel therapies against the nosocomial fungal pathogen Candida auris. Here we provide detailed descriptions of methods for assessing cellular viability of Candida auris in vitro, such as metabolic assays (XTT and resazurin), colony-forming unit counting, live/dead quantitative PCR, and fluorescent staining for microscopic analyses.

Investigating the Transcriptome of Candida albicans in a Dual-Species Staphylococcus aureus Biofilm Model

Candida albicans is an opportunistic pathogen found throughout multiple body sites and is frequently co-isolated from infections of the respiratory tract and oral cavity with Staphylococcus aureus. Herein we present the first report of the effects that S. aureus elicits on the C. albicans transcriptome. Dual-species biofilms containing S. aureus and C. albicans mutants defective in ALS3 or ECE1 were optimised and characterised, followed by transcriptional profiling of C. albicans by RNA-sequencing (RNA-seq). Altered phenotypes in C. albicans mutants revealed specific interaction profiles between fungus and bacteria. The major adhesion and virulence proteins Als3 and Ece1, respectively, were found to have substantial effects on the Candida transcriptome in early and mature biofilms. Despite this, deletion of ECE1 did not adversely affect biofilm formation or the ability of S. aureus to interact with C. albicans hyphae. Upregulated genes in dual-species biofilms corresponded to multiple gene ontology terms, including those attributed to virulence, biofilm formation and protein binding such as ACE2 and multiple heat-shock protein genes. This shows that S. aureus pushes C. albicans towards a more virulent genotype, helping us to understand the driving forces behind the increased severity of C. albicans-S. aureus infections.

Dyeing fungi: amphotericin B based fluorescent probes for multiplexed imaging

The clinically used antifungal polyene amphotericin B was conjugated, via the mycosamine and the aglycon moieties, to fluorophores. The Cy5 conjugated probe showed selective labelling of fungi in the presence of bacteria, allowing multiplexed imaging and identification of microbial species in a co-culture of fungi and Gram-positive and Gram-negative bacteria.

Non-typeable Haemophilus influenzae chronic colonization in chronic obstructive pulmonary disease (COPD)

Haemophilus influenzae is the most common cause of bacterial infection in the lungs of chronic obstructive pulmonary disease (COPD) patients and contributes to episodes of acute exacerbation which are associated with increased hospitalization and mortality. Due to the ability of H. influenzae to adhere to host epithelial cells, initial colonization of the lower airways can progress to a persistent infection and biofilm formation. This is characterized by changes in bacterial behaviour such as reduced cellular metabolism and the production of an obstructive extracellular matrix (ECM). Herein we discuss the multiple mechanisms by which H. influenzae contributes to the pathogenesis of COPD. In particular, mechanisms that facilitate bacterial adherence to host airway epithelial cells, biofilm formation, and microbial persistence through immune system evasion and antibiotic tolerance will be discussed.

Using IPM-CPR as a Management Program for Apple Orchards

We have demonstrated how management of key orchard pests including the insect invasive species Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) can be accomplished using a systems-level approach termed IPM-CPR (Integrated Pest Management-Crop Perimeter Restructuring) in apple. We conducted on-farm comparisons of IPM-CPR to standard management program for managing H. halys, Cydia pomonella (L.) (Lepidoptera: Tortricidae), Grapholita molesta (Busck) (Lepidoptera: Tortricidae), and Lygus lineolaris Palisot de Beauvois (Hemiptera: Miridae) in commercial apple orchards in 2014, 2016, and 2017 in New Jersey, Maryland, and Virginia. The presence and abundance of key pests and fruit injury at harvest were used as a measure of success of the program. We compared the amount of insecticide applied for each management program. In majority of instances, there were no differences in the IPM-CPR and the standard management program in terms of H. halys numbers in baited pyramid traps and stink bug injury at harvest. Damage from C. pomonella and G. molesta in the IPM-CPR treatment was significantly lower than the standard management program in 2014 and 2017. Amount of active ingredient used was on average 62.1% lower in the IPM-CPR treatment compared with standard management program. Despite a reduction in insecticide use, there were minimal impacts on beneficial insects. Overall, IPM-CPR in apples successfully managed key orchard pests, including H. halys, and used significantly less insecticide than a standard insecticide-based management program and could be adopted as a systems-level approach for pest population reduction.

Chitosan Ameliorates Candida auris Virulence in a Galleria mellonella Infection Model

Candida auris has emerged as a multidrug-resistant nosocomial pathogen over the last decade. Outbreaks of the organism in health care facilities have resulted in life-threatening invasive candidiasis in over 40 countries worldwide. Resistance by C. auris to conventional antifungal drugs such as fluconazole and amphotericin B means that alternative therapeutics must be explored. As such, this study served to investigate the efficacy of a naturally derived polysaccharide called chitosan against aggregative (Agg) and nonaggregative (non-Agg) isolates of C. aurisin vitro and in vivo. In vitro results indicated that chitosan was effective against planktonic and sessile forms of Agg and non-Agg C. auris In a Galleria mellonella model to assess C. auris virulence, chitosan treatment was shown to ameliorate killing effects of both C. auris phenotypes (NCPF 8973 and NCPF 8978, respectively) in vivo Specifically, chitosan reduced the fungal load and increased survival rates of infected Galleria, while treatment alone was nontoxic to the larvae. Finally, chitosan treatment appeared to induce a stress-like gene expression response in NCPF 8973 in the larvae likely arising from a protective response by the organism to resist antifungal activity of the compound. Taken together, results from this study demonstrate that naturally derived compounds such as chitosan may be useful alternatives to conventional antifungals against C. auris.

Polymicrobial oral biofilm models: simplifying the complex

Over the past century, numerous studies have used oral biofilm models to investigate growth kinetics, biofilm formation, structure and composition, antimicrobial susceptibility and host-pathogen interactions. In vivo animal models provide useful models of some oral diseases; however, these are expensive and carry vast ethical implications. Oral biofilms grown or maintained in vitro offer a useful platform for certain studies and have the advantages of being inexpensive to establish and easy to reproduce and manipulate. In addition, a wide range of variables can be monitored and adjusted to mimic the dynamic environmental changes at different sites in the oral cavity, such as pH, temperature, salivary and gingival crevicular fluid flow rates, or microbial composition. This review provides a detailed insight for early-career oral science researchers into how the biofilm models used in oral research have progressed and improved over the years, their advantages and disadvantages, and how such systems have contributed to our current understanding of oral disease pathogenesis and aetiology.

Candida auris exhibits resilient biofilm characteristics in vitro: implications for environmental persistence

Surfaces within healthcare play a key role in the transmission of drug-resistant pathogens. Candida auris is an emerging multidrug-resistant yeast which can survive for prolonged periods on environmental surfaces. Here we show that the ability to form cellular aggregates increases survival after 14 days, which coincides with the upregulation of biofilm-associated genes. Additionally, the aggregating strain demonstrated tolerance to clinical concentrations of sodium hypochlorite and remained viable 14 days post treatment. The ability of C. auris to adhere to and persist on environmental surfaces emphasizes our need to better understand the biology of this fungal pathogen.

Candida albicans Mycofilms Support Staphylococcus aureus Colonization and Enhances Miconazole Resistance in Dual-Species Interactions

Polymicrobial inter-kingdom biofilm infections represent a clinical management conundrum. The presence of co-isolation of bacteria and fungi complicates the ability to routinely administer single antimicrobial regimens, and synergy between the microorganisms influences infection severity. We therefore investigated the nosocomial pathogens Staphylococcus aureus and Candida albicans with respect to antimicrobial intervention. We characterized the interaction using biofilm assays and evaluated the effect of miconazole treatment using in vitro and in vivo assays. Finally, we assessed the impact of biofilm extracellular matrix (ECM) on these interactions. Data indicated that the C. albicans mycofilms supported adhesion and colonization by S. aureus through close interactions with hyphal elements, significantly increasing S. aureus biofilm formation throughout biofilm maturation. Miconazole sensitivity was shown to be reduced in both mono- and dual-species biofilms compared to planktonic cells. Within a three-dimensional biofilm model sensitivity was also hindered. Galleria mellonella survival analysis showed both enhanced pathogenicity of the dual-species infection, which was concomitantly desensitized to miconazole treatment. Analysis of the ECM revealed the importance of extracellular DNA, which supported the adhesion of S. aureus and the development of the dual-species biofilm structures. Collectively, these data highlight the clinical importance of dual-species inter-kingdom biofilm infections, though also provides translational opportunities to manage them more effectively.

Adjunctive raloxifene treatment improves attention and memory in men and women with schizophrenia

There is increasing clinical and molecular evidence for the role of hormones and specifically estrogen and its receptor in schizophrenia. A selective estrogen receptor modulator, raloxifene, stimulates estrogen-like activity in brain and can improve cognition in older adults. The present study tested the extent to which adjunctive raloxifene treatment improved cognition and reduced symptoms in young to middle-age men and women with schizophrenia. Ninety-eight patients with a diagnosis of schizophrenia or schizoaffective disorder were recruited into a dual-site, thirteen-week, randomized, double-blind, placebo-controlled, crossover trial of adjunctive raloxifene treatment in addition to their usual antipsychotic medications. Symptom severity and cognition in the domains of working memory, attention/processing speed, language and verbal memory were assessed at baseline, 6 and 13 weeks. Analyses of the initial 6-week phase of the study using a parallel groups design (with 39 patients receiving placebo and 40 receiving raloxifene) revealed that participants receiving adjunctive raloxifene treatment showed significant improvement relative to placebo in memory and attention/processing speed. There was no reduction in symptom severity with treatment compared with placebo. There were significant carryover effects, suggesting some cognitive benefits are sustained even after raloxifene withdrawal. Analysis of the 13-week crossover data revealed significant improvement with raloxifene only in attention/processing speed. This is the first study to show that daily, oral adjunctive raloxifene treatment at 120 mg per day has beneficial effects on attention/processing speed and memory for both men and women with schizophrenia. Thus, raloxifene may be useful as an adjunctive treatment for cognitive deficits associated with schizophrenia.

Staphylococcal chromosome cassette evolution in Staphylococcus aureus inferred from ccr gene complex sequence typing analysis

Staphylococcal chromosome cassette mec (SCCmec) elements within major lineages of healthcare- and community-associated methicillin-resistant Staphylococcus aureus (MRSA) clones were characterised using intra-SCCmec multilocus sequencing. A strong correlation was observed between sequence- and PCR-based typing methods (p <0.001). However, phylogenetic analysis of the SCCmec locus using concatenated sequences evidenced few recombination events. Sequence type (ST)-SCCmec1 was found in SCCmec elements types I and IV, suggesting the evolution of an SCCmecI element into an SCCmecIV element. This coincided with the spread of the clone harbouring this SCCmec element into the community. No correlation was observed between ST-SCCmec lineage and MRSA lineage, confirming multiple acquisitions of SCCmec by S. aureus. This was exemplified by the SCCmecIV ST-SCCmec10 element, which was detected in all of the clonal complexes examined, including healthcare- and community-associated MRSA. The acquisition of this SCCmec element was five- to ten-fold more common than that of others. Models of MRSA clone evolution suggest that this SCCmec was first found in the paediatric clone.

Bimatoprost: A Novel Antiglaucoma Agent

The aim of glaucoma therapy is to preserve vision by reducing intraocular pressure (IOP). Following recent National Eye Institute sponsored studies, it is becoming increasingly apparent that every mmHg of extra IOP lowering counts. Bimatoprost is the newest and most effective addition to the physician's armamentarium of ocular hypotensive drugs. Direct clinical comparisons have demonstrated that it is more efficacious than the prostaglandin (PG) FP receptor agonist prodrugs, latanoprost and travoprost, as well as a beta-adrenoceptor antagonist, timolol, alone or in fixed combination with the carbonic anhydrase inhibitor, dorzolamide. Moreover, patients that are refractory to latanoprost therapy may be successfully treated with bimatoprost. Such evidence provides support, at the clinical level, for the contention that bimatoprost is pharmacologically distinct from PG FP receptor agonist prodrugs. Bimatoprost is a structural analog of PGF2alpha-ethanolamide (prostamide F2alpha), which is formed from the endocannabinoid anandamide by a biosynthetic pathway involving cyclooxygenase-2 (COX-2). Their pharmacology is remarkably similar, such that bimatoprost may be regarded as a prostamide mimetic. The target receptor for bimatoprost and the prostamides appears unique and unrelated to PG- and endocannabinoid-sensitive receptors. Extensive ocular distribution/metabolism studies in non-human primates demonstrate that bimatoprost is not a prodrug, it remains essentially intact. Its profound ocular hypotensive effects may, therefore, be attributed to its prostamide-mimetic properties.

A GRASP55-rab2 effector complex linking Golgi structure to membrane traffic

Membrane traffic between the endoplasmic reticulum (ER) and Golgi apparatus and through the Golgi apparatus is a highly regulated process controlled by members of the rab GTPase family. The GTP form of rab1 regulates ER to Golgi transport by interaction with the vesicle tethering factor p115 and the cis-Golgi matrix protein GM130, also part of a complex with GRASP65 important for the organization of cis-Golgi cisternae. Here, we find that a novel coiled-coil protein golgin-45 interacts with the medial-Golgi matrix protein GRASP55 and the GTP form of rab2 but not other Golgi rab proteins. Depletion of golgin-45 disrupts the Golgi apparatus and causes a block in secretory protein transport. These results demonstrate that GRASP55 and golgin-45 form a rab2 effector complex on medial-Golgi essential for normal protein transport and Golgi structure.

Alcohol home delivery services: a source of alcohol for underage drinkers

OBJECTIVE

This study describes the use of alcohol home delivery services by underage drinkers, and characteristics of grocery and liquor stores that deliver alcohol. The availability of alcohol home delivery services across the United States is also described.

METHOD

Individuals surveyed were from 15 small- and medium-sized midwestern communities. Of all enrolled 12th graders, 83.5% (N = 4,487) responded, and of a randomly selected cohort of 18- to 20-year-olds, 93.9% (N = 1,721) responded. All grocery stores that sold alcohol and liquor stores in the corresponding communities were invited to participate in the study and 124 (92.5%) of those businesses completed surveys regarding outlet characteristics and practices. Data for the surveys were based on a nested cross-sectional design with individual respondents nested within the 15 communities.

RESULTS

Purchases of delivered alcohol were made by 10% of 12th graders and 7.3% of 18- to 20-year-olds within the past year; 20.2% of outlets delivered alcohol. Using bivariate analyses, purchasing delivered alcohol was associated with male gender, high-risk drinking (drinking five or more drinks on an occasion), more recent and more frequent drinking. Providing delivery services was more common among outlets selling keg beer and/or single servings. Multivariate analyses revealed positive associations between purchasing delivered alcohol and male gender for the 12th graders, and high risk and more recent drinking for both the 12th graders and 18- to 20-year-olds. For outlets, selling keg beer was positively associated with providing delivery services. A separate survey indicated that home delivery services appear to be available in many areas of the country.

CONCLUSIONS

Home delivery is a previously unidentified source of alcohol for underage drinkers that could be curtailed with effective alcohol policies.

Conservation, class and custom: lifespace and conflict in a nineteenth-century forest environment

Cannon… is busy now bringing fern from the moor to use as bedding, he has cut it about a mile off up the lane behind Belle Green. It is a rough road to bring it down. I think I will go up next time with the cart and help the children to rake it, it is such a nice crackly fern.

At the East Grinstead Petty Sessions in March 1868 Charles, sixth Earl De La Warr brought ten poor men forward charged with oak and beech underwood cutting and trespass. George Edwards the Reeve had discovered six men cutting and tying, another three with handbills but who were not actually cutting at the time, and Abraham Card ‘a woodbuyer, etc.’ loading the wood onto his wagon. Edwards had cautioned the men against cutting: ‘When I got to them I read a paragraph from Mr Hunt's letter [Hussey Hunt, De La Warr's steward, warning against litter cutting]. They laughed and went on cutting. I then gave them all into custody’. It appears that the men were handcuffed and led away. Daniel Heasman, one of the men once again, was convicted and originally imprisoned for 21 days, the other defendants were originally fined 1s. damages, 1s. penalty and costs.

Management of postmenopausal osteoporosis for primary care

OBJECTIVE

The shift in health care delivery from a subspecialty to primary care system has transferred the responsibility of preventing osteoporotic fractures from specialists in metabolic bone disease to the web of physicians--family practitioners, general internists, pediatricians, and gynecologists--who provide the bulk of primary care. The challenge for this group of physicians is to decrease the rising prevalence of osteoporotic hip and vertebral fractures while operating within the cost parameters. It is the goal of this brief summary to provide primary practitioners with focused guidelines for the management of postmenopausal osteoporosis based on new and exciting developments. Prevention and treatment will change rapidly over the next decade and these advances will require changes in these recommendations.

DESIGN

We identified patients at risk for osteoporosis and provided indications for bone mass measurement, criteria for diagnosis of osteoporosis, therapeutic interventions, and biochemical markers of the disease.

RESULTS

Prevention and treatment are discussed, including hormone replacement therapy and use of calcitonin, sodium fluoride, bisphosphonates, and serum estrogen receptor modulators.

CONCLUSIONS

Postmenopausal osteoporosis should no longer be an accepted process of aging. It is both preventable and treatable. Primary care physicians must proactively prevent and treat osteoporosis in their daily practice, and combination therapies are suggested.

Anger of African American women in the south

In this existential-phenomenological investigation middle-class African American women (n = 9) in the Southern United States were interviewed about their experience of anger in daily life. The purpose of the study was to examine what African American women's anger is about, what it means, and how it is experienced. Transcribed interviews were analyzed using a hermeneutic process. The thematic structure of African American women's anger comprises three main elements that stand out as figural: power, control, and respect. These figural elements can be understood only when seen against the ground of a racist Southern culture that produces pervasive mistrust. These findings are of importance to clinicians, who cannot deliver culturally competent interventions to African American female clients without a clear understanding of the complexity and meaning of their anger experience.

Effects of endothelin receptor antagonism and angiotensin-converting enzyme inhibition on cardiac and renal remodeling in the rat

The effects of a nonpeptide, orally active mixed endothelin (ET) ETA/ETB receptor antagonist, SB 217242, and an angiotensin-converting enzyme (ACE) inhibitor, ramipril, were evaluated after inter-renal aortic banding in the rat. Separate sham, vehicle, and treatment groups were compared in each study. In vehicle-treated animals in the ramipril group, aortic banding for 4 weeks produced significant cardiac hypertrophy (247 +/- 5 mg/100 g bw vs. 305 +/- 11 mg/100 g bw; p < 0.001), right (upstream) renal hypertrophy (380 +/- 6 mg/100 g bw vs. 559 +/- 28 mg/100 g bw; p < 0.001), and significant left (downstream) renal atrophy (405 +/- 4 mg/100 g bw vs. 192 +/- 25 mg/100 g bw; p < 0.001). Continuous ramipril treatment (1 mg/kg p.o. once daily), begun 3 days before aortic banding, inhibited cardiac hypertrophy (305 +/- 11 mg/100 g bw vs. 266 +/- 7 mg/100 g bw; p < 0.05) but did not alter renal hypertrophy or atrophy. In a similarly designed study, SB 217242 (30 mg/kg p.o. b.i.d.) had no effect on the development of cardiac hypertrophy (298 +/- 7 mg/100 g bw vs. 310 +/- 12 mg/100 g bw) or renal hypertrophy (561 +/- 15 mg/100 g bw vs. 575 +/- 19 mg/100 g bw), but abolished the development of renal atrophy (158 +/- 16 mg/100 g bw vs. 395 +/- 19 mg/100 g bw; p < 0.001). [125I]ET-1 radioligand binding experiments indicated that the density of both ETA and ETB receptors was increased dramatically (three- to fourfold) in the atrophic kidney cortex compared to sham or hypertrophic kidneys. In situ hybridization studies indicate an upregulation of ETB receptor mRNA in the glomeruli of atrophic kidneys within 5 days of aortic banding. In conclusion, an angiotensin-dependent mechanism may mediate cardiac hypertrophy associated with aortic banding, whereas ET-dependent mechanisms may mediate an atrophic response in the hypoperfused kidney, perhaps through an interaction with upregulated ETA and/or ETB receptors.

Alcohol-related problems among black, Hispanic and white men: the contribution of neighborhood poverty

OBJECTIVE

We examined the cross-sectional relationships between race/ethnicity, neighborhood poverty and alcohol-related problems among black, Hispanic and white male drinkers. Test hypotheses were that black and Hispanic men living in more impoverished neighborhoods would report increased numbers of alcohol-related problems than comparable white men.

METHOD

Study hypotheses were tested in a sample of 744 black, Hispanic and white men participating in the 1992 National Alcohol Follow-up Survey. Study hypotheses were analyzed using generalized linear model regression analysis.

RESULTS

Neighborhood poverty had a greater effect on alcohol-related problems in black than in white men, partially supporting our hypothesis. Black men living in more impoverished neighborhoods reported greater numbers of alcohol-related problems than comparable white men; there were no race differences among more affluent men. Neighborhood poverty had little effect on alcohol-related problems in Hispanic men.

CONCLUSIONS

Findings suggest that, giving unfavorable economic conditions, black men will report greater numbers of alcohol-related problems than comparable white men.

An interdisciplinary team approach to implementing the ketogenic diet for the treatment of seizures

The ketogenic diet is becoming a more recognized method of treating seizures in some children with epilepsy. Texas Scottish Rite Hospital for Children (TSRHC) developed an interdisciplinary team that uses a comprehensive approach to implementing this innovative therapy. Anticipated outcomes of this unique approach are increased family satisfaction and improved dietary compliance, which maximizes the diet to its fullest potential. These outcomes are validated by anecdotal information by families' reports of satisfaction and successful diet maintenance for increased number of months (this population from 3-31 months). Of the 27 children ages 1-16 years, approximately 40% have experienced reduction of seizures of more than 50%, 25% are seizure free, and 35% have discontinued the diet for a variety of reasons including difficulty in consistently maintaining the diet. Originally introduced in the 1920s, the ketogenic diet has once again become cutting edge treatment for nonresponsive seizure activity.

Relationships among alcohol availability, drinking location, alcohol consumption, and drinking problems in adolescents

We examined relationships among perceived alcohol availability, drinking location, alcohol consumption, and drinking problems. Subjects were 3,372 adolescent drinkers, ages 16-18, who participated in the Communities Mobilizing for Change on Alcohol Project baseline survey. Mixed-model regression was employed to identify predictors of alcohol consumption and drinking consequences. Perceived alcohol availability was significantly associated with higher levels of alcohol consumption for males. Drinking in a public location with higher levels of alcohol consumption for females. Results underscore the importance of youth alcohol assessibility.

Thrombin increases clusterin mRNA in glomerular epithelial and mesangial cells

Clusterin, a multifunctional protein with complement blocking activity, and fibrin, a product of thrombin's enzymatic activity, are present in the kidney during acute and chronic renal failure. The role of thrombin in regulating clusterin mRNA in the kidney is not known. The effect of thrombin on clusterin mRNA expression was examined in rat glomerular mesangial and glomerular epithelial cells, and cultured human renal proximal tubular epithelial cells by northern blot. Thrombin (10(-8) M) increased clusterin mRNA levels two- to fourfold in glomerular mesangial, glomerular epithelial, and proximal tubule epithelial cells. This was a specific effect of thrombin receptor activation because peptides corresponding to the tethered ligand of the thrombin receptor were also able to increase clusterin mRNA levels. Epidermal growth factor, insulin-like growth factor-1, and transforming growth factor-beta 1 had little or no effect on clusterin mRNA levels. The protein kinase C inhibitor RO-32-0432 (1 microM) inhibited the thrombin-induced increase in clusterin mRNA, suggesting that thrombin receptor activation may regulate renal clusterin mRNA levels through protein kinase C.

Environmental predictors of drinking and drinking-related problems in young adults

We examined relationships among drinking norms, peer alcohol use, alcohol availability, drinking location, alcohol consumption, and drinking-related problems among young adult drinkers. The specific objectives of our study were to assess the relative contribution of normative and physical environmental factors to drinking and drinking consequences. Subjects were 3,095 young adults, aged eighteen to twenty years old who participated in the Communities Mobilizing for Change on Alcohol Project baseline survey. Alcohol consumption (i.e., number of drinks on the last occasion) and drinking consequences served as dependent variables. Multiple linear regression was used to identify predictors of alcohol consumption, and logistic regression was employed to identify predictors of drinking consequences. Drinking norms and peer alcohol use were positively related to alcohol consumption and to drinking consequences. Drinking in a public setting was positively related to alcohol consumption, but not to drinking-related problems. Findings suggest that policies and programs that alter the normative and physical environment surrounding drinking may reduce alcohol consumption and subsequent problems in young adults.

Measurement of alcohol and tobacco availability to underage students

Communities Mobilizing for Change on Alcohol (CMCA) and Tobacco Policy Options for Prevention (TPOP) are randomized multicommunity trials designed to reduce the availability of alcohol (CMCA) and tobacco (TPOP) products to underage youth. We assessed the test-retest reliability and internal consistency of perceived availability measures developed for surveys of middle and high school students. Two questionnaires were administered twice, each to separate student populations (CMCA: 9th graders; TPOP; 8th graders) 21 to 26 days apart. A total of 111 (CMCA) and 70 (TPOP) subjects participated at both times (participation rate of 93.3% and 84.3%, respectively). There were no statistically significant differences in the distribution of demographic variables, alcohol or tobacco use variables, or availability variables across administrations. The scales assessing perceived access to alcohol or tobacco had high internal consistency (Cronbach's alpha of 0.84 for alcohol and 0.77 for tobacco), but moderate to low test-retest correlations (0.58 and 0.13, respectively). Single-item measures of sources of alcohol and tobacco and reported buy attempts also had moderate to low test-retest correlates (0.10-0.65). We recommend that items assessing tobacco and alcohol availability to underage youth be further developed.

Intraclass correlation among measures related to alcohol use by school aged adolescents: estimates, correlates and applications in intervention studies

School-based alcohol use prevention studies frequently employ designs in which schools are assigned to treatment conditions while observations are made on individuals. The nesting of schools within treatment conditions requires that the treatment effect be assessed against the between-school variance; unfortunately, that variance is usually larger than for randomly constituted groups and its precision is usually less than that for the within-school variance. These factors often combine to reduce power substantially. To address these problems, investigators need good estimates for the intraclass correlation which together with the number of observations per school determines the magnitude of the extra variation in the nested design. This article presents estimates of school-level intraclass correlation for measures related to alcohol use among ninth and twelfth grade students and discusses their use in planning new studies and analyzing previous or current studies.

Intraclass correlation among measures related to alcohol use by young adults: estimates, correlates and applications in intervention studies

OBJECTIVE

Alcohol intervention studies that allocate intact social groups to study conditions require adjustment to the usual analytic methods to account for the positive intraclass correlation that exists in such groups. This article presents intraclass correlations for measures related to alcohol use among young adults and discusses the use of those estimates to plan new studies.

METHOD

Young adults aged 18-20 were selected at random from driver's license lists in each of the 15 communities participating in the Communities Mobilizing for Change on Alcohol project. Respondents were surveyed by telephone to assess their drinking habits and other factors related to alcohol use. Community-level intraclass correlations were computed for those measures, both prior to and after adjustment for person- and community-level covariates.

RESULTS

The community-level intraclass correlations tend to be small, with larger values for belief and attitude items than for self-reported behaviors. Even so, correlations of this magnitude can have important deleterious effects on the power to detect important treatment effects in an otherwise well-designed and well-executed study. Adjustment for person-level covariates often reduced those correlations, and adjustment for community-level covariates often reduced them substantially.

CONCLUSIONS

There is measurable variation in measures related to alcohol use among young adults that is attributable to their community of residence. With adjustment for selected person- and community-level covariates, the magnitude of these correlations can be sharply reduced allowing the investigator to plan a more efficient community trial.

High risk sexual behavior and alcohol consumption among bar-going gay men

OBJECTIVES

To determine whether alcohol use prior to sexual behavior influenced the occurrence of unprotected anal intercourse among bar-going gay men.

METHODS

Anonymous AIDS behavioral risk surveys were administered to men entering gay bars in 16 cities on three nights in February 1993 in six states in the United States.

RESULTS

Of the 1519 men who completed the survey, 85% were current alcohol drinkers. Men who had unprotected anal intercourse after consuming alcohol drank more and reported more incidents of unprotected anal intercourse than men who had unprotected anal intercourse but not after drinking. Overall, unprotected anal intercourse occurred less frequently after alcohol consumption than without prior consumption.

CONCLUSIONS

This study found that heavy alcohol use and frequent high-risk sexual behavior occurred among the same individuals. However, we found no evidence for a causal link between alcohol use and unprotected sexual behavior in this sample of bar-going gay men.

Distinguishable groups of musculoskeletal low back pain patients and asymptomatic control subjects based on physical measures of the NIOSH Low Back Atlas

STUDY DESIGN

The authors performed an empirical prospective study of 115 patients referred to physical therapy for low back pain and 112 control subjects of similar age and gender.

OBJECTIVES

The authors defined and compared subgroups based on physical tests and described demographic and psychosocial characteristics by group.

SUMMARY OF BACKGROUND DATA

Prospective studies of intervention for persons with low back pain are limited by inability to randomize subjects into distinguishable groups. Previous attempts have not been empirical and have not focused on musculoskeletal LBP.

METHODS

Ten physical therapists administered 52 tests and 6 questionnaires to subjects in seven different clinics. Data were subjected to reliability and cluster and comparative analyses.

RESULTS

Tests were reliable. Groups were distinguished by measures of symmetry, flexibility, strength, and dynamic mobility.

CONCLUSION

Distinguishable groups can be determined; decreased trunk mobility characterized all groups of patients and imbalances in muscle length, strength, and symmetry described specific groups of subjects with and without low back pain.

Selective inhibition of 5-lipoxygenase attenuates glomerulonephritis in the rat

Three hours following injection of anti-GBM (glomerular basement membrane) antibody (10 mg/kg, i.v.) into rats, glomerular production of LTB4 was significantly increased as compared to untreated rats (497 +/- 26 vs. 244 +/- 18 pg of LTB4/mg protein). Twenty-four hours following administration of anti-GBM antibody, renal function (blood urea nitrogen, BUN; plasma creatinine, PCr; creatinine clearance, CCr; fractional excretion of sodium, FENa; fractional excretion of urea, FEUrea) was determined to be impaired proportionally to the amount of injected antibody (5 to 30 mg/kg, i.v.). In a second series of experiments, a selective 5-lipoxygenase (5-LO) inhibitor, SK&F 107649, was used to investigate the involvement of 5-LO products in the pathophysiology of anti-GBM antibody-induced glomerulonephritis. In preliminary experiments. SK&F 107649 (50 to 200 mg/kg, p.o.) inhibited ionophore (A23187)-stimulated whole blood leukotriene (LT) B4 production in a dose-dependent fashion (P < 0.05 at doses > or = 100 mg/kg). The anti-GBM antibody-mediated decrease in glomerular filtration rate (GFR) and increase in BUN and PCr were dose-dependently attenuated by SK&F 107649 (50 to 200 mg/kg, p.o. BID). These data confirm that glomerular LTB4 production is stimulated in anti-GBM antibody-induced glomerulonephritis, and demonstrate that inhibition of 5-LO by SK&F 107649 normalizes BUN and PCr and attenuate the decrease in GFR following anti-GBM antibody treatment. These results provide additional evidence for a role of 5-LO products in immune-mediated renal disease, and suggest that pharmacologic inhibition of 5-LO may be of therapeutic value.