Antimicrobial efficacy of sequentially applied eugenol against food spoilage micro-organisms

AIMS

Compare the survival behaviour of food spoilage micro-organisms treated with sequential doses or all at once treatments of eugenol.

METHODS AND RESULTS

Staphylococcus carnosus, Listeria innocua, Escherichia coli and Pseudomonas fluorescens were exposed to a minimal lethal concentration (MLC) initially, or to half doses over time, with first half dose applied immediately and a second half dose applied after 3, 4, 6 and 8 h, of eugenol. Direct plate counts were determined at regular time intervals. Population dynamics were analysed using a combined growth and mortality model. Effect of sequential dosing varied significantly between tested organisms. High antimicrobial efficacy on E. coli K12 was observed regardless of timing of the two doses. Reduced effectiveness was observed against Staph. carnosus and L. innocua the later the second half dose was applied. Complete cell reduction occurred after immediate exposure to full MLC dose, while sequential half doses were bacteriostatic regardless of application times.

CONCLUSION

Time in between antimicrobial dose application had substantial impact on effectiveness, attributed to organisms becoming more tolerant.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study contributes to the evaluation of encapsulated antimicrobial systems, where antimicrobials are released over time and antimicrobial concentrations may only reach MLC levels after some time.

Fundamentalism, Multiculturalism and Problems of Conducting Research with Populations in Developing Nations

A growing number of nurse researchers travel globally to conduct research in poor and underserved populations in developing nations. These researchers, while well versed in research ethics, often find it difficult to apply traditional ethical standards to populations in developing countries. The problem of applying ethical standards across cultures is explained by a long-standing debate about the nature of ethical principles. Fundamentalism is the philosophical stance that ethical principles are universal, while the anthropologically-based ‘multicultural’ model claims the philosophical position that principles are culturally bound. The authors explicate the two philosophical stances and advocate a morally sensitive but moderate position of ‘ethical multiculturalism’ rather than favouring either of the above philosophical positions. The final section suggests ways to promote ethical multiculturalism while planning and conducting nursing research.

Outbreak of Botulism After Consumption of Illicit Prison-Brewed Alcohol in a Maximum Security Prison--Arizona, 2012

The authors investigated the second botulism outbreak to occur in a maximum security prison in Arizona within a 4-month period. Botulism was confirmed in eight men aged 20 to 35 years who reported sharing a single batch of pruno made with potatoes. Initial symptoms included blurred vision, slurred speech, muscle weakness, ptosis, and dysphagia. All patients received heptavalent botulinum antitoxin, seven required mechanical ventilation, and all survived. The median incubation period was 29 hours. Sera from all patients and leftover pruno tested positive for botulinum toxin type A. Botulism should be considered among prisoners with cranial nerve palsies and descending, symmetric flaccid paralysis. Prison-brewed alcohol, particularly when made with potatoes, can be a vehicle for botulism and is associated with outbreaks of botulism in prisons.

Pertinent parameters in photo-generation of electrons: Comparative study of anatase-based nano-TiO2 suspensions

In the field of solar fuel cells, the development of efficient photo-converting semiconductors remains a major challenge. A rational analysis of experimental photocatalytic results obtained with material in colloïdal suspensions is needed to access fundamental knowledge required to improve the design and properties of new materials. In this study, a simple system electron donor/nano-TiO2 is considered and examined via spin scavenging electron paramagnetic resonance as well as a panel of analytical techniques (composition, optical spectroscopy and dynamic light scattering) for selected type of nano-TiO2. Independent variables (pH, electron donor concentration and TiO2 amount) have been varied and interdependent variables (aggregate size, aggregate surface vs. volume and acid/base groups distribution) are discussed. This work shows that reliable understanding involves thoughtful combination of interdependent parameters, whereas the specific surface area seems not a pertinent parameter. The conclusion emphasizes the difficulty to identify the key features of the mechanisms governing photocatalytic properties in nano-TiO2.

VALIDATION OF THE LYMPHEDEMA LIFE IMPACT SCALE (LLIS): A CONDITION-SPECIFIC MEASUREMENT TOOL FOR PERSONS WITH LYMPHEDEMA

Evidence-based practice supports the use of validated outcome measures to assess the impact of lymphedema; however, condition-specific lymphedema assessment measures are needed. The Lymphedema Life Impact Scale (LLIS) was developed as a comprehensive, lymphedema-specific instrument to assess the effects of lymphedema in any extremity. The LLIS is an 18-item measure of physical, psychosocial, and functional impairments caused by lymphedema. The purpose of this multicenter, cross sectional study was to investigate the reliability and validity of the LLIS. Test-retest reliability was assessed in a subgroup of 17 participants. Internal consistency and validity was assessed in 71 participants with upper (nUE = 37) or lower limb (nLE = 34) lymphedema, and a control group of 31 participants without lymphedema. Intraclass correlation coefficients for test-retest reliability ranged from .965 to .990. Cronbach's alpha coefficients for internal consistency ranged between .841 and .926. Construct validity of the LLIS was upheld with symptoms, but not with edema severity. The LLIS correlated highly with other comparison measures used in this study. Minimal clinically important difference of the LLIS was 7.31; MDC95 = 11.53. Our results showed the LLIS to be a valid and reliable tool for the assessment of severity of impairment among patients with lymphedema.

Alcohol Production, Prevention Strategies, and Inmate Knowledge About the Risk for Botulism From Pruno Consumption in a Correctional Facility--Arizona, 2013

During July to November 2012, two botulism outbreaks (12 cases total) occurred in one all-male prison; both were associated with illicitly brewed alcohol (pruno) consumption. Inmate surveys were conducted to evaluate and develop prevention and education strategies. Qualitative surveys with open-ended questions were performed among inmates from rooms where outbreaks occurred to learn about pruno consumption. Quantitative surveys assessed knowledge gained after the outbreaks and preferred information sources. For the quantitative surveys, 250 inmates were randomly selected by bed from across the correctional facility and 164 inmates were interviewed. Only 24% of inmates reported any botulism knowledge before the outbreaks and education outreach, whereas 73% reported knowledge after the outbreaks (p < .01). Preferred information sources included handouts/fliers (52%) and the prison television channel (32%).

Notes from the Field: Tickborne Relapsing Fever Outbreak at an Outdoor Education Camp - Arizona, 2014

Tickborne relapsing fever (TBRF) is a bacterial infection characterized by recurring episodes of fever, headache, muscle and joint aches, and nausea. In North America, TBRF primarily is caused by Borrelia hermsii spirochetes transmitted by Ornithodoros hermsii ticks. Once infected, these soft ticks are infectious for life and transmit the spirochete to sleeping humans quickly (possibly within 30 seconds) during short feeds (15-90 minutes). On August 10, 2014, the Coconino County Public Health Services District in Arizona was notified by a local hospital that five high school students who attended the same outdoor education camp had been hospitalized with fever, headache, and myalgias. Hantavirus infection initially was suspected because of reported exposure to rodent droppings, but after detecting spirochetes on peripheral blood smears from all five hospitalized students, TBRF was diagnosed. The camp was instructed to close immediately, and the health department, in collaboration with local university experts, investigated to identify additional cases, determine the cause, and prevent further infections. A total of 11 cases (six confirmed and five probable) were identified.

[First data concerning the medical supply of patients with non-alcoholic fatty liver disease in Germany - a survey in university hospital centers of hepatology]

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) currently is one oft the most common reasons for chronic liver injury in the western world. In the European and American population the prevalence is up to 30 %. The medical supply of German patients with NAFLD is variable and has not been analyzed to date.

METHODS

We sent questionnaires to all university liver centers in Germany (11 questions) concerning the medical supply of patients with NAFLD. Questions included the rate of patients with fatty liver disease in the outpatient clinics, metabolic comorbidities and the kind of assignment. Besides that, individual clinical standards were documented. We compared longitudinal changes between 2008 and 2013.

RESULTS

The return rate of questionnaires was 65 % (n = 20). Analysis showed that the portion of NAFLD patients in the university outpatient clinics had increased between 2008 and 2013 with the predominant part of patients being assigned from external practitioners and not from internal departments of the hospital. Only few patients were assigned by diabetologists or endocrinologists, but on the other hand most liver outpatient clinics investigated their NAFLD patients for metabolic disorders. Cooperation between liver outpatient clinics and other medical services was moderate and was rated average, joint conferences were held rarely. Follow-up visits of patients with NAFLD take place regularly in all centers, however based on different criterions. A consistent algorithm concerning risk assessment and invasive workup does not exist.

CONCLUSION

The awareness concerning patients with NAFLD seems to have grown in recent years. Nevertheless, the medical supply of these patients is quite heterogenous and consistent standards do not exist. Therefore, a common guidline is urgently required.

From mild to wild fluctuations in crystal plasticity

Macroscopic crystal plasticity is classically viewed as an outcome of uncorrelated dislocation motions producing Gaussian fluctuations. An apparently conflicting picture emerged in recent years emphasizing highly correlated dislocation dynamics characterized by power-law distributed fluctuations. We use acoustic emission measurements in crystals with different symmetries to show that intermittent and continuous visions of plastic flow are not incompatible. We demonstrate the existence of crossover regimes where strongly intermittent events coexist with a Gaussian quasiequilibrium background and propose a simple theoretical framework compatible with these observations.

Tickborne relapsing fever - United States, 1990-2011

Tickborne relapsing fever (TBRF) is a zoonosis caused by spirochetes of the genus Borrelia and transmitted to humans by ticks of the genus Ornithodoros. TBRF is endemic in the western United States, predominately in mountainous regions. Clinical illness is characterized by recurrent bouts of fever, headache, and malaise. Although TBRF is usually a mild illness, severe sequelae and death can occur. This report summarizes the epidemiology of 504 TBRF cases reported from 12 western states during 1990-2011. Cases occurred most commonly among males and among persons aged 10‒14 and 40‒44 years. Most reported infections occurred among nonresident visitors to areas where TBRF is endemic. Clinicians and public health practitioners need to be familiar with current epidemiology and features of TBRF to adequately diagnose and treat patients and recognize that any TBRF case might indicate an ongoing source of potential exposure that needs to be investigated and eliminated.

Kristall- und Molekülstruktur von 5.10-Dihydro-5.10-diniethylphenaziniiimtniodid und 5.10-Dihydro-5.10-diethylphenaziniumtriiodid / Molecular and Crystal Structure of 5,10-Dihydro-5.10-dimethylphenaziniumtriiodide and 5.10-Dihydro-5.10-diethylphenazinium triiodide

Oxidation of 5,10-dihydro-5,10-dimethylphenazine and 5,10-dihydro-5,10-diethyl-phenazine under different reaction conditions leads to several iodine containing solids. The preparation and X-ray structure of two of them, 5,10-dihydro-5,10-dimethyl-phcnaziniumtriiodide (3) and 5,10-dihydro-5,10-diethylphenaziniumtriiodido (4) are reported here.

Compound 3 crystallizes in space group P21/n with lattice parameters a = 8.552(6) Å, b= 16.953(2) Å, c- 12.157(9) Å and β= 103.46(2)° with four formula units in the unit cell. The structure was refined to an R-value of 0.046 using 2387 independent reflections. The lattice constains distinct, slightly distorted triiodide ions and bent 5,10-dihydro-5,10-dimethylphenazinium radical cations. Compound 4 crystallizes in the same space group P21/n with lattice parameters a = 8.531(6) Å, b = 8.332(21) Å, c = 13.320(15) Å and β= 94.44(19)° with two formula units in the unit cell. The structure was refined to an R-value of 0.076 using 1195 independent reflections. The lattice contains strictly linear symmetrical triiodide ions and planar centrosymmetrical 5,10-dihydro-5,10-diethyl- phenazinium radical cations.

Electrostatic interactions of cationic lauric arginate with anionic polysaccharides affect antimicrobial activity against spoilage yeasts

AIMS

To investigate the effect of anionic polysaccharides often used in beverage applications (xanthan and λ-carrageenan) on the antimicrobial efficacy of the cationic surfactant lauric arginate (LAE) against typical spoilage yeasts.

METHODS AND RESULTS

The antimicrobial efficacy of LAE against Saccharomyces cerevisiae, Candida albicans and Zygosaccharomyces bailii in the absence and presence of anionic polysaccharides was assessed by microtitre and macrobroth dilution assays. Combining LAE with either xanthan or λ-carrageenan caused a pronounced decrease in LAE's antimicrobial efficacy, with the minimal inhibitory and lethal concentrations (MIC and MLC) both increasing with increasing polysaccharide concentration. This reduction in antimicrobial efficacy was more pronounced for the addition of λ-carrageenan. To determine the cause of loss of activity, physical properties of solutions were examined. Turbidity and sedimentation measurements indicated that complexes between LAE and anionic polysaccharides had been formed. Electrophoresis measurements showed that complexes had varying electrical charges and dimensions depending on solution composition.

CONCLUSION

Results suggest that electrostatic interactions between LAE and anionic polysaccharides play a major role in complex formation and loss of antimicrobial activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

Results have important implications for the utilization of LAE as an antimicrobial agent in beverage and food products containing anionic polysaccharides.

Serologic survey for exposure following fatal Balamuthia mandrillaris infection

Granulomatous amebic encephalitis (GAE) from Balamuthia mandrillaris, a free-living ameba, has a case fatality rate exceeding 90% among recognized cases in the USA. In August 2010, a GAE cluster occurred following transplantation of infected organs from a previously healthy landscaper in Tucson, AZ, USA, who died from a suspected stroke. As B. mandrillaris is thought to be transmitted through soil, a serologic survey of landscapers and a comparison group of blood donors in southern Arizona was performed. Three (3.6%) of 83 serum samples from landscapers and 11 (2.5%) of 441 serum samples from blood donors were seropositive (p = 0.47). On multivariable analysis, county of residence was associated with seropositivity, whereas age, sex, and ethnicity were not. Exposure to B. mandrillaris, previously unexamined in North America, appears to be far more common than GAE in Southern Arizona. Risk factors for disease progression and the ameba's geographic range should be examined.

Effect of water velocity on hydroponic phytoremediation of metals

The influence of flow velocity on the uptake of cadmium, copper, lead, and zinc by hydroponically grown soft stem bulrush (Scirpus validus) was investigated. The roots of the plants were exposed to a continually recycled, nutrient enriched, synthetic stormwater. Plants were divided into groups and the roots of each group exposed to different but constant water velocities. The metal concentrations in the roots and stems were compared after three weeks. Metal accumulation in roots was increased for water velocities between 1.3 and 4.0 cm s(-1). In a second experiment, the roots of all plants were exposed to a single velocity and the root and stem metal concentrations were determined as a function of time. Metal concentrations in the roots approached a constant value after three weeks. After this time, accumulation of metals depends upon root growth. The results suggest that long-term accumulation by the roots of hydroponic Scirpus validus can be increased by increasing water velocity, which implies that floating islands with movement will retain more metals from the water column.

Self-reported information sources and perceived knowledge in individuals with lymphedema

Currently, a limited number of studies have been conducted that examine sources of information and knowledge level in individuals with lymphedema. This study aimed (1) to examine self-reported information sources and perceived lymphedema knowledge among individuals with lymphedema; and (2) to examine differences in self-reported information sources and perceived lymphedema knowledge among individuals with primary or secondary lymphedema; and with upper or lower extremity lymphedema. The National Lymphedema Network (NLN) conducted a survey to collect self-report data from March 2006 to January 2010. Overall, participants preferred a variety of sources of information. Participants reported low levels of knowledge about the types of lymphedema, treatment approaches and methods, and self-administrated therapies. In comparison to participants with secondary or upper extremity lymphedema, participants with primary or lower extremity lymphedema reported lower knowledge level regarding causes of lymphedema, risks for and complications of lymphedema, treatment approaches and methods for lymphedema, and self-administered therapies. Opportunities exist to expand lymphedema information sources. Healthcare professionals should focus on delivering high quality information about treatment and self-care management to individuals with lymphedema.

[Is vocational reintegration of young cancer patients possible?]

BACKGROUND

Besides an improvement in quality of life, one of the major targets of rehabilitation programmes is to preserve the ability to work and to integrate the patient into working life again. Cancer in particular is often associated with a loss of employment and joblessness, frequently caused by incomplete rehabilitation.

METHODS

The programme is aimed at young cancer patients aged between 18 and 40 years. In addition to medical rehabilitation, they undergo a specially developed programme which they complete in groups of no more than 5 persons. At baseline and at the end of the 3 weeks rehabilitation, tests on physical and mental capacity are conducted. During rehabilitation, different training programmes concerning mobility at work, fine motor skills and cognitive abilities are held, complemented by an intensive psycho-social training programme. Additionally, patients receive individual social counselling.

RESULTS

So far, 34 patients with an average age of 31.8 years have participated in the programme, 65% of them suffering from malignant haematological diseases. The combination of a medical and a vocational rehabilitation programme was judged extremely positively by the participants, which remained the case 6 months after completion of the programme. The rehabilitation programme significantly reduced work incapacity periods: at baseline, only 6% of the participants had not experienced such periods, but after 3 and 6 months, this rate had increased to 61% and 62% respectively. This was accompanied by an increased health-related quality of life and reduced fatigue.

CONCLUSION

With our pilot project we were able to show that such a programme is feasible, can be well integrated into clinical routine and is successful.