Host population effects on ectomycorrhizal fungi vary between low and high phosphorus soils of temperate rainforests

Geographic distinctions in the affinity of tree populations for select ectomycorrhizal fungi (EMF) may occur where strong edaphic pressures act on fungal communities and their hosts. We examine this premise for Pseudotsuga menziesii var. menziesii of southwest British Columbia, using ten native seedlots collected from a range of mean annual precipitation (MAP), as a proxy for podzolization extent and phosphorus (P) deficiencies, and evaluated in contrasting low P and high P soils. After two growing seasons, seedling biomass in the high P soil dwarfed that of the low P soil, and better growth rates under high P were detected for populations from very dry and very wet origins. EMF communities on the high P soil displayed more symmetry among host populations than the low P soil (average community dissimilarity of 0.20% vs. 0.39%, respectively). Seedling foliar P% differed slightly but significantly in relation to MAP of origin. EMF species richness varied significantly among host populations but independently of climatic parameters. There were significant shifts in EMF species abundance related to seedlot MAP, particularly on the low P soil where nonlinear relationships were found for Wilcoxina mikolae, Hyaloscypha finlandica, and Rhizopogon villosulus. Despite efforts to enhance colonization by native fungi, the predominance of ruderal EMF species hindered a realistic evaluation of local adaptation among host-fungi populations. Nevertheless, the shifting affinity in taxa abundance and wider community disparity on low P soil reflected the potential for a consequential host genetic effect related to geographical patterns in P availability across temperate rainforests.

Efficacy and safety of a supplement combination on hand pain among people with symptomatic hand osteoarthritis an internet-based, randomised clinical trial the RADIANT study

OBJECTIVE

The RADIANT study aimed to investigate the efficacy and safety of a complementary medicine supplement combination in people with hand osteoarthritis (HOA).

METHOD

This was an internet-based, double-blind, randomised, placebo-controlled trial. Participants aged over 40 years with symptomatic HOA with radiographic confirmation (Kellgren Lawrence grade ≥ 2) throughout Australia were recruited and randomly assigned (1:1) to receive either a supplement combination composed of Boswellia serrata extract 250 mg/day, pine bark extract 100 mg/day, methylsulfonylmethane 1,500 mg/day and curcumin 168 mg/day or placebo for 12 weeks. The primary outcome was change in hand pain assessed using a visual analogue scale (VAS 0-100) from baseline to week 12. A range of secondary outcomes and additional measures were recorded. Adverse events were monitored weekly.

RESULTS

One hundred and six participants were included with mean age 65.6 years and 81% were women. 45% of the participants were graded as KLG 4, 40% KLG three and 39 (37%) had erosive OA. There was no significant difference in pain VAS reduction between groups. The adjusted between group difference in means (95%CI) was 5.34 (-2.39 to 13.07). Five participants (10%) in the supplement combination group discontinued study treatment due to AE vs four participants (7%) in the placebo group.

CONCLUSION

There were no significant differences in symptomatic relief between the two groups over 12 weeks. These findings do not support the use of the supplement combination for treating hand pain in people with HOA.

REGISTRATION

Prospectively registered (Australian New Zealand Clinical Trials Registry ACTRN12619000835145, 31/05/2019).

Pan-Canadian Framework for Palliative and End-of-Life Care Research

Background and context: Ongoing advances have been made in the conceptualization and operationalization of palliative and end-of-life care (PEOLC) (e.g., palliative approaches to care, early identification of people who would benefit from palliative care). In addition, Canada has been a leader in PEOLC research and continues to have an internationally recognized research community. However, many Canadians continue to experience unnecessary pain and suffering at the end of life and receive care inconsistent with their goals and preferences. Within this context, the Canadian Cancer Research Alliance (CCRA) sought to develop a national research framework to guide Canada's cancer research funders in response to their strategic priority to improve the patient experience and quality of life for all cancer patients. Aim: To develop and implement a national framework and recommendations to enable funders to capitalize on existing research strengths and build capacity to address unmet needs to advance the field and broaden the scope, beyond its historical affiliation with advanced cancer, to include PEOLC for all those living and dying with life-limiting conditions. Strategy/Tactics: The framework's development was informed by multiple approaches, including: a strategic literature review; an analysis of PEOLC research funding in Canada from 2005-13; and an online survey and key informant interviews from the broader stakeholder community. Program/Policy process: A working group of CCRA member representatives and palliative care experts met regularly to provide guidance and feedback to a consultant who synthesized the data and formulated recommendations. In total, > 200 stakeholders (e.g., patients, caregivers, researchers, volunteers, practitioners, decision-makers, and policy-makers) provided input through the survey and interviews. Outcomes: The Pan-Canadian Framework for Palliative and End-of-Life Research was released March 2017. It emphasizes priorities for research funding across three broad themes: 1) Transforming models of care; 2) Patient and family centredness; and 3) Ensuring equity. The identified research priorities are underpinned by four building blocks: capacity building; knowledge, synthesis, exchange, and implementation; data access and standardization; and research network development. What was learned: Successful implementation of the framework's recommendations requires strong leadership from champions within the community. The formation of the Pan-Canadian Palliative Care Research Collaborative led by palliative care clinician-researchers, in response to the identified need for a research network, is an example of an early success resulting from release of the framework. Continued efforts are needed to ensure ongoing uptake of the framework's recommendations. CCRA members have commenced planning to identify next steps for joint action.

Historical epidemiology of hepatitis C virus in select countries-volume 4

Due to the introduction of newer, more efficacious treatment options, there is a pressing need for policy makers and public health officials to develop or adapt national hepatitis C virus (HCV) control strategies to the changing epidemiological landscape. To do so, detailed, country-specific data are needed to characterize the burden of chronic HCV infection. In this study of 17 countries, a literature review of published and unpublished data on HCV prevalence, viraemia, genotype, age and gender distribution, liver transplants and diagnosis and treatment rates was conducted, and inputs were validated by expert consensus in each country. Viraemic prevalence in this study ranged from 0.2% in Hong Kong to 2.4% in Taiwan, while the largest viraemic populations were in Nigeria (2 597 000 cases) and Taiwan (569 000 cases). Diagnosis, treatment and liver transplant rates varied widely across the countries included in this analysis, as did the availability of reliable data. Addressing data gaps will be critical for the development of future strategies to manage and minimize the disease burden of hepatitis C.

The present and future disease burden of hepatitis C virus infections with today's treatment paradigm: Volume 4

Factors influencing the morbidity and mortality associated with viremic hepatitis C virus (HCV) infection change over time and place, making it difficult to compare reported estimates. Models were developed for 17 countries (Bahrain, Bulgaria, Cameroon, Colombia, Croatia, Dominican Republic, Ethiopia, Ghana, Hong Kong, Jordan, Kazakhstan, Malaysia, Morocco, Nigeria, Qatar and Taiwan) to quantify and characterize the viremic population as well as forecast the changes in the infected population and the corresponding disease burden from 2015 to 2030. Model inputs were agreed upon through expert consensus, and a standardized methodology was followed to allow for comparison across countries. The viremic prevalence is expected to remain constant or decline in all but four countries (Ethiopia, Ghana, Jordan and Oman); however, HCV-related morbidity and mortality will increase in all countries except Qatar and Taiwan. In Qatar, the high-treatment rate will contribute to a reduction in total cases and HCV-related morbidity by 2030. In the remaining countries, however, the current treatment paradigm will be insufficient to achieve large reductions in HCV-related morbidity and mortality.

Strategies to manage hepatitis C virus infection disease burden-Volume 4

The hepatitis C virus (HCV) epidemic was forecasted through 2030 for 17 countries in Africa, Asia, Europe, Latin America and the Middle East, and interventions for achieving the Global Health Sector Strategy on viral hepatitis targets-"WHO Targets" (65% reduction in HCV-related deaths, 90% reduction in new infections and 90% of infections diagnosed by 2030) were considered. Scaling up treatment and diagnosis rates over time would be required to achieve these targets in all but one country, even with the introduction of high SVR therapies. The scenarios developed to achieve the WHO Targets in all countries studied assumed the implementation of national policies to prevent new infections and to diagnose current infections through screening.

Nitrogen uptake over entire root systems of tree seedlings

Uptake of nitrogen (N) by sequential root regions in six tree species was measured in roots of 16- to 26-month-old seedlings at 50 and 1500 µM NH4NO3 concentration, at the cell level using oscillating microelectrodes and at the root region level using enriched (15)N application. Our objective was to determine the root regions making the greatest contribution to total N uptake in each species as measured by the two contrasting techniques. White and condensed tannin zones were the regions with the smallest surface area in all species, but these zones often had the highest net flux of NH4(+) and NO3(-). For most species, little variation was found among root regions in N flux calculated using a (15)N mass balance approach, but where significant differences existed, high N flux was observed in white, cork or woody zones. When N fluxes measured by each of the two methods were multiplied by the estimated surface area or biomass of each root region, the effect of root region size had the greatest influence on regional N uptake. Root regions of greatest overall N uptake were the cork and woody zones, on average. Total N uptake may thus be greatest in older regions of tree seedling roots, despite low rates of uptake per unit area.

Assessing the effectiveness of retrograde autologous priming of the cardiopulmonary bypass machine in isolated coronary artery bypass grafts

INTRODUCTION

Currently, around 35-80% of patients undergoing cardiac surgery in the UK receive a blood transfusion. Retrograde autologous priming (RAP) of the cardiopulmonary bypass circuit has been suggested as a possible strategy to reduce blood transfusion during cardiac surgery.

METHODS

Data from 101 consecutive patients undergoing isolated coronary artery bypass grafts (where RAP was used) were collected prospectively and compared with 92 historic patients prior to RAP use in our centre.

RESULTS

Baseline characteristics (ie age, preoperative haemoglobin [Hb] etc) were not significantly different between the RAP and non-RAP groups. The mean pump priming volume of 1,013ml in the RAP group was significantly lower (p<0.001) than that of 2,450ml in the non-RAP group. The mean Hb level at initiation of bypass of 9.1g/dl in patients having RAP was significantly higher (p<0.001) than that of 7.7g/dl in those who did not have RAP. There was no significant difference between the RAP and non-RAP groups in transfusion of red cells, platelets and fresh frozen plasma, 30-day mortality, re-exploration rate and predischarge Hb level. The median durations of cardiac intensive care unit stay and in-hospital stay of 1 day (inter-quartile range [IQR]: 1-2 days) and 5 days (IQR: 4-6 days) in the RAP group were significantly shorter than those of the non-RAP group (2 days [IQR: 1-3 days] and 6 days [IQR: 5-9 days]).

CONCLUSIONS

In the population group studied, RAP did not influence blood transfusion rates but was associated with a reduction in duration of hospital stay.

Efficacy and safety of long-term low-calorie diet in severely obese patients non-eligible for surgery

The aim of this study was to describe the long-term efficacy and safety of low-calorie diets (LCDs; providing 900 kcal day(-1) ) in obese patients who have failed to achieve adequate weight loss with standard medical management and are non-eligible for surgical therapeutic options. Charts from a regional hospital-based outpatient bariatric programme were reviewed. Eight patients (75% male, age 60.1 ± 7.8 years) with severe obesity (body mass index 57.1 ± 8.8 kg m(-2) ) and undergoing long-term LCD (33 ± 10 months) were identified. Variables of interest included anthropometric, cardiovascular risk and nutritional parameters, thyroid, renal and liver function, changes in medications, side effects and adverse events. Average weight loss was 44 ± 15 kg (27 ± 13% of initial weight) at 24 months. Long-term management with LCD resulted in substantial and sustained improvements in glucose homeostasis, blood pressure and lipid profile. LCD was well tolerated with minor self-limited side effects. Over the follow-up period, two subjects underwent coronary revascularization and one patient underwent knee replacement surgery - all recovered without complications. These findings suggest that in selected obese patients (non-eligible for surgery), long-term management with LCD may provide an alternative option for substantial and sustainable weight loss with significant improvements in metabolic and cardiovascular health.

Adherence to treatment of primary osteoporosis and its association to fractures--the Swedish Adherence Register Analysis (SARA)

SUMMARY

Osteoporosis treatments reduce the risk of fractures. The objective of this study was to investigate adherence to treatment of osteoporosis and its association to fractures in Sweden. Adherence to treatment of osteoporosis in Sweden is poor, and time on treatment was found to be significantly associated with fracture incidence.

INTRODUCTION

The objective of this study was to estimate persistence and compliance to treatment of primary osteoporosis in Sweden. A second aim was to investigate the determinants of non-persistence and the association between adherence and fracture incidence.

METHODS

Patients were identified through filled prescriptions for alendronate, risedronate, strontium ranelate, and raloxifene between 2005 and 2009 from the Swedish Prescribed Drug Register. Persistence was investigated using survival analysis. Medication possession ratio (MPR) was used to measure compliance in persistent patients. The outcome measure in the analysis of adherence and fracture incidence was hospitalized osteoporotic fractures.

RESULTS

The final cohort consisted of 56,586 treatment-naïve patients (mean age 71, 86% women). A total of 51%, 35%, 25%, and 14% were still on treatment (switching allowed) after 1, 2, 3, and 4 years, respectively. Average MPR in persistent patients was 94.2% (CI(95) 94.2-94.3%). Compared with <1 month of therapy, treatment for 1 month to 1 year, 1 to 2 years, and 2 to 3 years was associated with a lower 3-year fracture incidence (HR 0.86, p = 0.091; HR 0.67, p < 0.001; and HR 0.59, p < 0.001, respectively). No significant relationship was identified between MPR and fracture risk.

CONCLUSIONS

Persistence to treatment of osteoporosis in Sweden is poor and approximately 50% of all treatment-naïve patients discontinue therapy within 1 year. Average refill compliance, estimated only while the patients were persistent, was found to be close to perfect. A strong association was identified between treatment persistence and fracture incidence, which calls for action to improve the current situation.

Limits on the high-energy gamma and neutrino fluxes from the SGR 1806-20 giant flare of 27 December 2004 with the AMANDA-II detector

On 27 December 2004, a giant gamma flare from the Soft Gamma-Ray Repeater 1806-20 saturated many satellite gamma-ray detectors, being the brightest transient event ever observed in the Galaxy. AMANDA-II was used to search for down-going muons indicative of high-energy gammas and/or neutrinos from this object. The data revealed no significant signal, so upper limits (at 90% C.L.) on the normalization constant were set: 0.05(0.5) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the gamma flux and 0.4(6.1) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the high-energy neutrino flux.

Pall eBDS: an enhanced bacterial detection system for screening platelet concentrates

Bacterial contamination of blood components remains a significant problem in transfusion medicine. The Pall enhanced bacterial detection system (Pall eBDS) detects the presence of bacteria in leucodepleted platelet concentrates by measuring the reduction of oxygen in the sample, due to aerobic bacterial growth. Pooled platelet concentrates were spiked at 10 cfu mL(-1) with 10 organisms (one species per bag). Pall eBDS pouches were inoculated with the spiked platelet concentrates. After 24 and 30 h of incubation, the oxygen level was measured. A further set of pouches were taken from the inoculated platelet concentrates at 24 h. Incubation and reading intervals were as for the initial set of pouches. A sensitivity study was also performed comparing the Pall eBDS with the BacT/ALERT system. Spiking at 10 cfu mL(-1) and immediately sampling into Pall eBDS pouches resulted in 97.6 and 100% detection after an incubation period of 24 and 30 h, respectively. After 24 h of incubation of the spiked platelet concentrates and then sampling into Pall eBDS pouches, 99.1% detection was obtained after incubation for both 24 and 30 h. The sensitivity of the Pall eBDS and BacT/ALERT is similar and in the order of 1 cfu mL(-1). Implementation of either BacT/ALERT or Pall eBDS for routine screening of platelet concentrates has the potential to further increase the safety of the blood supply.

Use of a solid-phase fluorescent cytometric technique for the detection of bacteria in platelet concentrates

Blood services worldwide are now striving to reduce the risk of transmission of bacteria by transfusion. The BacT/ALERT microbial detection system (bioMerieux, Basingstoke, Hants, UK) is currently regarded as the 'gold standard' for bacterial screening of platelet concentrates. The BacT/ALERT is a culture system and will not generate an 'instant' (within 2 h) determination. We report on the Scansystem (Hemosystem, Marseille, France), a solid-phase fluorescent cytometric technique, which enables the rapid detection of bacteria (within 90 min) in platelet concentrates. The study was performed in two parts - one involving the routine screening of platelet concentrates and the other determining the sensitivity of the system. In both arms of the study, the BacT/ALERT was used for comparative purposes. In total, 900 platelet concentrates were screened (63 apheresis and 837 buffy coat pooled). No bacteria were detected in any of the platelet concentrates tested by means of either the Scansystem or the BacT/ALERT. The sensitivity of the Scansystem was in the order of 10(3) cfu mL(-1). Escherichia coli and Staphylococcus aureus were detected by using the Scansystem at 1 cfu mL(-1). The BacT/ALERT detected all organisms tested (n = 6) at 1 cfu mL(-1). The Scansystem offers a sensitive alternative technology to bacterial culture, with the benefit of a rapid test time.

A novel method for the detection of bacteria in platelet concentrates utilizing oxygen consumption as a marker for bacterial growth

Bacterial transfusion-transmission remains a significant problem in transfusion medicine. Diversion and improved donor arm disinfection has been introduced by blood services to reduce bacterial transmissions. These interventions are not 100% effective and, therefore, there is still a requirement to screen blood donations, particularly platelet concentrates which are responsible for the majority of transmissions. Pall BDS, a novel bacterial testing system, detects the presence of bacteria in platelet concentrates by measuring the reduction in oxygen content associated with bacterial growth. Buffy coat-derived pooled platelet concentrates were spiked with 12 aerobic and two anaerobic organisms (one species per bag, n = 10) at 100-700 cfu mL(-1). Samples were taken into Pall BDS sample pouches and incubated for 0, 24, 30 and 48 h. An initial incubation was undertaken at 35 degrees C for 24 h and subsequent incubation was at 22 degrees C. At the end of the incubation period the oxygen content in the Pall BDS pouches was measured using a gas analyser. An oxygen content less than or equal to 19.5% was deemed to be positive. Pall BDS pouches tested positive in 80, 94 and 98% units spiked with aerobic bacteria at 24, 30 and 48 h, respectively. Anaerobic bacteria were not detected by the system. Positive BDS pouches contained 10(6) cfu mL(-1) or greater. The system was simple and easy to perform. Pall BDS has a closed sampling system which prevents exogenous contamination. This initial study indicates that the Pall BDS offers a practicable system for detecting bacteria present in leucodepleted platelet concentrates.

Evaluation of the 3D BacT/ALERT automated culture system for the detection of microbial contamination of platelet concentrates

Bacterial transmission remains the major component of morbidity and mortality associated with transfusion-transmitted infections. Platelet concentrates are the most common cause of bacterial transmission. The BacT/ALERT 3D automated blood culture system has the potential to screen platelet concentrates for the presence of bacteria. Evaluation of this system was performed by spiking day 2 apheresis platelet units with individual bacterial isolates at final concentrations of 10 and 100 colony-forming units (cfu) mL-1. Fifteen organisms were used which had been cited in platelet transmission and monitoring studies. BacT/ALERT times to detection were compared with thioglycollate broth cultures, and the performance of five types of BacT/ALERT culture bottles was evaluated. Sampling was performed immediately after the inoculation of the units, and 10 replicates were performed per organism concentration for each of the five types of BacT/ALERT bottles. The mean times for the detection of these 15 organisms by BacT/ALERT, with the exception of Propionibacterium acnes, ranged from 9.1 to 48.1 h (all 10 replicates were positive). In comparison, the time range found using thioglycollate was 12.0-32.3 h (all 10 replicates were positive). P. acnes' BacT/ALERT mean detection times ranged from 89.0 to 177.6 h compared with 75.6-86.4 h for the thioglycollate broth. BacT/ALERT, with the exception of P. acnes, which has dubious clinical significance, gave equivalent or shorter detection times when compared with the thioglycollate broth system. The BacT/ALERT system detected a range of organisms at levels of 10 and 100 cfu mL-1. This study validates the BacT/ALERT microbial detection system for screening platelets. Currently, the system is the only practically viable option available for routinely screening platelet concentrates to prevent bacterial transmission.

Vertical impact increase in middle age may explain idiopathic weight-bearing joint osteoarthritis

OBJECTIVE

To test the hypothesis that ground reaction force increases when a standard stepping task is performed in late middle age.

DESIGN

Consecutive sample.

SETTING

Internal medicine practice.

PARTICIPANTS

Thirty-six male patients (age range, 17-72yr) from an internal medicine practice.

INTERVENTION

Subjects performed 20 consecutive footfall impacts onto a force platform while barefoot and while wearing shoes.

MAIN OUTCOME MEASURES

Ground reaction forces were recorded for each footfall.

RESULTS

Impact is positively related to age both when barefoot (r = .84, p < .001) and when wearing shoes (r = .71, p < .001). Impact remains constant until age 50, after which it increases by 13.3% for barefoot subjects. Barefoot impact was significantly lower and less variable than impact when shod (barefoot = 1.18 body weight [BW]; shod = 1.22 BW; F(1,5) = 169.91, p < .001).

CONCLUSION

An increase in impact force during locomotion was identified that occurs in late middle age, when stability declines and idiopathic weight-bearing joint osteoarthritis develops. Because impact is negatively related to stability, the impact rise is probably caused by postural adjustments to instability resulting from irreversible neurologic decline. This heightened impact may account for the accelerated rate of weight-bearing joint osteoarthritis that begins in late-middle age.

Evaluation of the BacT/Alert automated blood culture system for detecting bacteria and measuring their growth kinetics in leucodepleted and non-leucodepleted platelet concentrates

BACKGROUND AND OBJECTIVE

To evaluate the BacT/Alert automated blood culture system for the detection of bacteria in platelet concentrates, and to determine bacterial growth kinetics in leucodepleted and non-leucodepleted units.

MATERIALS AND METHODS

Apheresis (Cobe Leucocyte Reduction System [LRS]) and pooled buffy coat-derived (Optipress) platelet concentrates (PCs) were tested. Six organisms were used for spiking the PCs: Clostridium perfringens, Bacillus cereus, Group B Streptococcus, Staphylococcus epidermidis, Staphylococcus aureus and Escherichia coli. Units were inoculated to give a final concentration of approximately equal to 1 and 50 colony-forming units (CFU)/ml. On days 0, 2 and 5, BacT/Alert standard aerobic and anaerobic bottles were inoculated with a 5-ml fill volume and bacteria were enumerated.

RESULTS

The BacT/Alert Automated blood culture system gave rapid determination times of spiked units, with all positives detected within 48 h and 98.1% detected within 24 h. In general, as the inoculum concentration increased, the detection time decreased. Rapid growth was obtained with all organisms tested except for B. cereus, which failed to grow on four occasions. Bacterial numbers on day 2 ranged from 10(5) to 10(11) CFU/ml and on day 5 ranged from 10(4) to 10(12) CFU/ml. Growth was not significantly greater in leucodepleted units.

CONCLUSIONS

The study confirmed that PCs are an excellent growth medium for bacteria. Rapid and substantial growth was obtained with all organisms under test. Leucodepletion does not appear to enhance bacterial proliferation. The BacT/Alert automated blood culture system could rapidly detect contamination of units. Bacterial screening using an automated blood culture system is therefore a potential option.

Loss of functional caveolae during senescence of human fibroblasts

Primary human fibroblasts have a finite replicative lifespan in culture that culminates in a unique state of growth arrest, termed senescence that is accompanied by distinct morphological and biochemical alterations. Senescent cell responses to extracellular stimuli are believed to be altered at a point after receptors are bound by ligand, leading to improper integration of the signals which initiate DNA replication. In this study we demonstrate that one of the key organizing membrane microdomains for receptor signaling, caveolae, are absent in senescent cells. A comparison of young and senescent cells indicated that senescent cells contained a higher total amount of caveolins 1 and 2 but had significantly less of both proteins in the caveolar fraction. Additionally, caveolar fractions from senescent cells completely lacked the tyrosine-kinase activity associated with functional caveolae. Furthermore, old cells had little caveolar protein exposed to the outer plasma membrane as estimated by using an in vivo biotinylation assay and no detectable caveolin 1 on the cell surface when processed for immunofluoresence and confocal microscopy. Together, these data suggest that a fundamental loss of signal integration at the plasma membrane of senescent cells is due to the loss of signaling competent caveolae.

Evaluation of donor arm disinfection techniques

BACKGROUND AND OBJECTIVE

To validate a standardized optimal national procedure for donor arm disinfection.

MATERIALS AND METHODS

A direct swabbing and plating technique was used to enumerate bacteria present on the arm pre- and postdisinfection. Twelve donor arm disinfection techniques were evaluated.

RESULTS

The Medi-Flex Adapted method, consisting of a two-stage process with an initial application of isopropyl alcohol followed by tincture of iodine, produced the best arm disinfection. A percentage reduction in bacterial counts of 99.79% (logarithmic reduction of 2.67) was obtained. Postdisinfection, 70% of donors had bacterial counts of zero, and 98% had counts of 10 or less.

CONCLUSION

The Medi-Flex disinfection method offers the English National Blood Service a validated, optimal 'best practice' disinfection technique and should contribute significantly to the reduction in risk of transmission of bacteria by transfusion.

The effects of active immunization against gnRH on testicular development, feedlot performance, and carcass characteristics of beef bulls

The objective was to determine the effects of a recombinant fusion protein anti-GnRH vaccine on testicular development, feedlot performance, and carcass quality of beef bulls. Crossbred beef bulls (n = 58, average weight 306 kg, 9 mo of age), were randomly allocated to two groups and received either an anti-GnRH vaccine (GnRH) or placebo (Control) by intramuscular injection on d 0, 56, and 112. There were group effects (P < 0.01; as a percentage of Control) on testicular weight (53%), daily sperm production (40%), and epididymal sperm reserves (16%). There were group x time interactions (P < 0.0001) for scrotal circumference and serum testosterone concentrations; at slaughter, bulls in the GnRH group had a smaller (P < 0.05) scrotal circumference (28.3 vs 33.9 cm) and lower (P < 0.05) serum testosterone concentrations (2.2 vs 8.6 ng/mL) than those in the Control group. Average daily gain, feed intake, and feed efficiency were not different between treatments during the backgrounding phase (d 0 to 84). During the finishing phase (d 98 to 182), ADG was greater (P < 0.05) for bulls in the Control group (1.69 vs 1.42 kg/d), as was carcass weight (6.9%; P < 0.01). However, GnRH bulls had numerically better feed efficiency (6.12 vs 7.08 kg DMI/kg gain; P < 0.23) and shear force values for ribeye that were 16% lower (P < 0.14) than Control bulls, warranting further investigation. Vaccinating bulls against GnRH suppressed testicular function, with growth and carcass characteristics similar to that expected with steers.

Robotic selective sampling and total automation for anti-CMV screening

The provision of anti-cytomegalovirus (CMV)-negative blood products causes the blood banking community considerable logistical problems. This is due firstly to the fact that only a select group of patients require anti-CMV-negative units, namely the immunocompromised. Secondly, the prevalence of CMV antibody in the blood donor population is high and, thirdly, the demand for anti-CMV-negative blood components continues to increase. To address this problem, a system of robotic selective sampling and total assay automation for anti-CMV screening has been developed. An in-house computer program generates a worklist from the donation database of samples requiring screening to meet clinical demand. Algorithms incorporated in the program ensure that the minimum number of samples possible are selected for provision of anti-CMV-negative products. This 'intelligent' selection of samples substantially reduces reagent cost. Robotic pipetting from the electronically derived worklist, masterplate to test plate robotic transfer and use of an automated assay processor maintains specific sample identification throughout. Results are read mechanically and transmitted directly to the main computer system. Robotic selective sampling and total assay automation produces an efficient, secure, auditable and completely traceable system for the provision of anti-CMV-negative units. The system produced a substantial reduction in labour costs with a 40% reduction in reagent usage. This system can be readily adapted for screening other markers on a selective basis.

Improving balance

OBJECTIVE

To test the hypothesis that shoes made with a sole material that retains compressed thickness between steps (low resiliency) provide balance better than and comfort equal to shoes composed of high resiliency sole material.

SETTING

Older subjects were recruited from a medical clinic population, and younger subjects came from a recreational sports population.

DESIGN

A randomized-order, cross-over, controlled comparison design.

PARTICIPANTS

Groups comprised random samples of 30 older (mean age 66 years, SD+/-3.0), and 30 younger (mean age 34 years, SD+/-6.0) healthy men who met age selection criteria.

MEASUREMENTS

Stability was inferred by sway measures: sway velocity (cm x s(-1)), X-Y area (cm2), and radial area (cm2). Comfort was measured by direct scaling and magnitude estimation using an 11-point ratio scale.

RESULTS

Stability inferred by sway velocity was 311% (P < .001) and 31% (P < .001) poorer for younger and older groups, respectively, for high and low resiliency interfaces. Sway velocity with low resiliency interface was lower than bare platform, the lowest ever recorded under equivalent conditions (P < .001). All interfaces were equally comfortable.

CONCLUSIONS

Stability rises with low resiliency interfaces and declines with high resiliency interfaces: sway velocity in older people wearing hard-soled footwear incorporating low resiliency technology would be 20% lower than in younger people wearing most current athletic and walking shoes. Inasmuch as existing theory can not account for improved balance with interfaces, we propose that when humans are supported by rigid support surfaces, elastic biologic tissues store energy from postural adjustments and locomotion, which is returned as a reaction force causing overshoot. This amplifies frontal plane foot movement and attenuates foot position awareness, causing less precise postural adjustments and instability. Low resiliency interfaces dissipate energy and thereby moderate overshoot. Low resiliency interface technology is capable of improving stability, which portends improved health for unstable older people in particular.

Osteoclastic activation is the principal mechanism leading to secondary osteoporosis in rheumatoid arthritis

OBJECTIVE

To use clinical measures and biochemical markers of bone turnover to investigate mechanisms of generalized bone loss in early rheumatoid arthritis (RA).

METHODS

We studied 232 patients with RA of less than 2 years' duration and 72 healthy controls using serial dual x-ray absorptiometry scanning of lumbar spine and hips. Patients attended the clinic for clinical and laboratory assessment with storage of serum, urine, and plasma at each visit. Change in bone mineral density (BMD) was calculated for patients and controls and compared with baseline and mean serial values of bone markers over the same intervals. Serum was assayed for procollagen I carboxyterminal propeptide (PICP) and skeletal alkaline phosphatase (sALP); urine for pyridinoline and deoxypyridinoline corrected for creatinine; and plasma for interleukin 1 (IL-1) and IL-6.

RESULTS

Patients lost bone significantly faster than controls at all sites (p < 0.01 for all). At first visit patients had significantly lower PICP levels than controls (p < 0.05) and sALP correlated with initial BMD in both patients (p < 0.01, r > 0.35, all sites) and controls (p < 0.0001, r > 0.50, all sites). We rescanned 167 patients at one year and 121 patients at 2 years. Mean urinary pyridinoline and deoxypyridinoline levels correlated strongly with BMD change at all sites, were increased in patients with active disease (p < 0.005), and correlated closely with mean C-reactive protein (CRP) (p < 0.005, r > 0.41 for both).

CONCLUSION

This study suggests that osteoclastic activation, rather than suppression of bone formation, is the dominant process leading to bone loss in early RA. Although urinary pyridinoline and deoxypyridinoline were excellent markers of BMD change, CRP was found to be best overall. This provides a rational approach for selecting and treating patients with RA to reduce their established longterm risk of osteoporotic fracture.

Factors associated with ankle injuries. Preventive measures

A sense of foot position in humans is precise when barefoot, but is distorted by athletic footwear, which accounts for the high frequency of ankle sprains in shod athletes. It is unclear whether taping and rigid and semi-rigid devices protect against ankle sprains, as all of the studies suggesting this are flawed by inadequate controls. If these devices do protect the ankle, it is not through added support but rather through a partial correction of the deceased foot position awareness caused by footwear. Since taping and rigid and semi-rigid devices interfere with normal movement, there is concern that these might actually increase the frequency of injury at the ankle and/or at different locations. In this respect, taping is less of a concern because it interferes least with normal movement. The best solution for reducing ankle sprains in shod athletes is the use of more advanced footwear to retain maximal tactile sensitivity, thereby maintaining an awareness of foot position comparable to that of the barefoot state or perhaps even improving on it.

Hazard of deceptive advertising of athletic footwear

OBJECTIVES

Athletic footwear are associated with frequent injury that are thought to result from repetitive impact. No scientific data suggest they protect well. Expensive athletic shoes are deceptively advertised to safeguard well through "cushioning impact", yet account for 123% greater injury frequency than the cheapest ones. This study tested the hypothesis that deceptive advertising creates a false sense of security with users of expensive athletic shoes, inducing attenuation of impact moderating behaviour, increased impact, and injury.

METHODS

Fifteen young healthy male volunteers confronted four surfaces: a bare force moment platform, and three with this platform covered by identical shoe sole material made to appear different and advertised divergently. Advertising messages suggested superior impact absorption and protection (deceptive message), poor impact absorption and high injury risk (warning message), and unknown impact absorption and safety (neutral message). Ground reaction forces were recorded for 10 barefoot footfalls, according to a protocol requiring stepping forward from perch to a surface 4.5 cm below.

RESULTS

Impact varied as a function of advertising message (p < 0.001). Deceptive message equalled neutral message in eliciting higher impact than the warning message and the bare platform. Differences grew with repetitions (p < 0.001).

CONCLUSIONS

These data provide a plausible mechanism explaining higher injury frequency in users of expensive athletic shoes. This is the first report to suggest: (1) deceptive advertising of protective devices may represent a public health hazard and may have to be eliminated presumably through regulation; (2) a tendency in humans to be less cautious when using new devices of unknown benefit because of overly positive attitudes associated with new technology and novel devices.

Balance and vertical impact in sports: role of shoe sole materials

OBJECTIVE

Athletic shoes and mats are support surface interfaces composed of relatively soft compressible materials designed to protect against injuries occurring in sports through force of vertical impact. Impact remains high with their use because humans land harder with them. We hypothesize that this hard-landing strategy is an attempt by the user to improve stability, by compressing the material to a less destabilizing thinner-stiff variety. We tested this hypothesis by comparing impact and balance on materials consisting of ethyl-vinyl acetate (EVA) foams of varying stiffness, identical to that found in soles of athletic footwear.

DESIGN

Randomized-order, crossover trial, controlled comparison, blinded.

SETTING

Volunteers were selected from the general community.

PARTICIPANTS

A random sample of 12 healthy men from the general population (mean age 30 years, SD +/- 6). Additional selection criteria were absence of disabilities influencing ability to walk, run, and balance, and no history of frequent falls.

METHODS

Impact testing and stability measures were performed on the same test day. Ground reaction forces were measured for ten barefoot footfalls. The protocol required stepping forward from perch to surface 4.5 cm below. Stability testing was performed with one-legged standing consisting of placing left foot on top of right for 30 sec, barefoot, eyes open, and gaze straight, with arms to side. Subjects confronted four surface conditions presented in random order: a bare rigid platform, and the platform covered with one of three 2.5-cm-thick materials.

RESULTS

Steady state vertical impact was a negative function of interface stiffness, with the softest interface producing the greatest vertical impact, and the stiffest interface the least vertical impact. Vertical impact and stability measures were also negatively related, with the strongest correlation obtained with the softest interface (r = -.87, p < .001). No relation between these variables was obtained for the rigid surface.

CONCLUSION

Balance and vertical impact are closely related. This supports the hypothesis that landing hard on soft surfaces is an attempt to transform the interface into a form associated with improved stability. According to these findings, currently available sports shoes and mats are too soft and thick, and should be redesigned to protect the persons using them.

Laparoscopically assisted spinal surgery

BACKGROUND

Spinal surgery is one of the newest frontiers of videolaparoscopic surgery, but requires the cooperative efforts of both the spinal surgeon and the laparoscopic general surgeon.

DATA BASE

We report our experience with 76 cases of laparoscopic spinal surgery, using both a transperitoneal and a retroperitoneal approach. Technical details and complications are described in detail.

CONCLUSIONS

Fifty-one patients had a transperitoneal approach with an average operating time of 117 minutes. Uncomplicated cases stayed 4.4 days. Five patients required conversion. All but one patient had L5-S1 level surgery. Twenty-five patients had a retroperitoneal approach with 150 minutes operating time and a 5.7 day stay. Conversions were minimized with a two-balloon technique. The retroperitoneal approach allows for multiple level surgery with virtually unlimited fusion devices. Laparoscopically assisted spine surgery affords all the benefits of minimally invasive surgery, without limitations for the spinal surgeon.

Foot position awareness in younger and older men: the influence of footwear sole properties

OBJECTIVES

To test the hypotheses that foot position awareness is related positively to stability, positively to shoe sole hardness, and negatively to shoe sole thickness, and that foot position awareness declines with advancing years.

SETTING

Older subjects were consecutive volunteers from a medical clinic; younger subjects were volunteers from the community.

DESIGN

Randomized-order, cross-over, controlled comparison.

PARTICIPANTS

Older subjects were a random sample of 13 healthy men, mean age 72.58 years, SD +/- 4.50. Younger subjects were a random sample of 13 male subjects from the general population, mean age 28.13 years, SD +/- 3.96. Additional selection criteria were absence of disabilities influencing ability to walk and no history of frequent falls.

MEASUREMENTS

Balance failure frequency, defined as falls per 100 meters of beam walking; rearfoot angle in degrees, measured via an optical position measurement system; perceived maximum supination when walking, in degrees, estimated by subjects using a ratio scale; foot position error, in degrees, was defined as the rearfoot angle minus perceived maximum supination.

RESULTS

Foot position error during walking: (1) increases with advancing years; footwear conditions absolute mean error for older sample of 15.48 degrees, SE +/- 1.56 degrees, and younger sample 5.44 degrees, SE +/- 1.03 degrees (P > .001); (2) is positively related to stability (r = .367, P < .001); (3) is positively related to midsole thickness (F(1,11) = 19.89, P < .001); (4) is negatively related to midsole hardness (F(2,22) = 29.80, P < .001); (5) correlates best with perceived maximum supination (r = .901, P < .001).

CONCLUSION

Foot position awareness is related causally to stability; shoes with thin, hard soles provide better stability for men than those with thick, soft midsoles. Foot position awareness declines with advancing years.

Studies on the mutagenicity of mild gasification products of coal and their subfractions by the Salmonella/microsomal assay

Mild gasification of coal is a technology being developed in the United States in order to upgrade lower rank coals and facilitate their use in coal-burning electric generation plants. Thirteen coal-derived mild gasification products from different coal sources and processing conditions have been examined for their potential biohazards. The mutagenicity of these samples was tested with the Ames Salmonella/microsomal assay. Two solvents, dimethyl sulfoxide (DMSO) and polyoxyethylene-sorbitan monooleate (Tween 80), were used to dissolve samples in a manner to facilitate their interaction with the test organisms. The results showed that 9 of the 13 samples displayed mutagenic activity in test strains TA98 and/or TA100 with or without metabolic activation, whether dissolved in Tween 80 or DMSO. Five mutagenic and two nonmutagenic samples were class-fractionated into basic, acidic, nonpolar, and polar neutral subfractions to examine their class-related mutagenic activities. Results of the testing of subfractions of the five mutagenic and one nonmutagenic samples showed mutagenic activity in at least the nonpolar neutral fraction. The subfractions of the another nonmutagenic sample did not display any mutagenic activity. Chemical characterization of the subfractions revealed the existence of aromatic hydrocarbons in certain subfractions, which may be responsible for the mutagenic activity of the coal-derived mild gasification products.

Semirigid instrumentation in the management of lumbar spinal conditions combined with circumferential fusion. A multicenter study

STUDY DESIGN

Patients with the diagnosis of degenerative disc conditions or spondylolisthesis undergoing circumferential fusion with posterior pedicle screw fixation using a semirigid rod were reviewed.

OBJECTIVES

To determine the effectiveness of this approach in achieving a spinal fusion and satisfactory clinical outcome, and to determine the complications associated with the procedure.

SUMMARY OF BACKGROUND DATA

The use of instrumentation to stabilize the lumbar motion segments and thereby enhance the fusion rate has been proposed in a number of studies. Semirigid fixation was believed to be effective in achieving these objectives without concern for stress-shielding, which was suggested by some authors using rigid fixation systems.

METHODS

Patients who required spinal fusion with anterior and posterior approaches because of specific lumbar pathology or previous surgeries were selected. The surgery consisted of an anterior interbody fusion using allograft, followed by a posterolateral fusion and pedicle screw fixation. Fusion was determined by continuity of trabecular bridging, and outcomes were determined by pain reduction and return to previous levels of activity. Fusion was considered solid if the two posterolateral areas were fused (Zones one and two), if the anterior interbody area was fused (Zone three), or if all three zones were fused. Complications were documented during and after surgery.

RESULTS

Sixty-two percent of patients had previous surgery with 25% of these patients having a diagnosis of pseudarthrosis. Fifty-five percent of patients had two or more levels fused, and 43% were heavy smokers. Ninety-seven percent of patients had successful fusions. Pain was significantly reduced on a pain analogue scale from 7.1 to 2.1 in the back and from 5.8 to 1.5 in the leg (p < 0.006 and 0.0001, respectively). Fifty-nine percent of patients returned to their previous level of activity, and 18% returned to lighter work or job retraining, for a total of 77% returning to the same or lighter levels of activity. Complications included metal failure, 4.9%; neurologic deficit, 1.2%; deep infection, 1.2%; deep venous thrombosis, 4.9%; and vascular injury, 2.4%. Fatal pulmonary embolus occurred in one patient.

CONCLUSION

This technique produces a satisfactory fusion rate (97%) and a good clinical outcome based on pain reduction and return to a satisfactory level of activity (77%). It is associated with few, but significant, complications that compare well with other reported series in a difficult group of patients. This procedure should be reserved for patients who are considered to be at high risk for not achieving spinal fusion.

Ankle taping improves proprioception before and after exercise in young men

Ankle sprains are common sports injuries. Inadequate foot position awareness is thought to be the fundamental cause of these injuries. Ankle taping may decrease risk of injury through improving foot position awareness. The benefit of taping is thought to decrease with duration of exercise because of poor tape adherence to human skin. This study was a randomized, crossover, controlled comparison experiment that tested the hypothesis that ankle taping improves foot position awareness before and after exercise. A sample of 24 healthy young blindfolded volunteers, wearing their own athletic shoes, indicated perceived slope direction and estimated slope amplitude when bearing full body weight and standing on a series of blocks. The top slope of the blocks varied between 0 degree and 25 degrees, in 2.5 degrees increments, to orient the plantar surface with respect to the leg toward pronation, supination, plantarflexion, and dorsiflexion, relative to its position on a flat surface. Foot position awareness, which was considered the reciprocal of surface slope estimate error, varied with testing condition, particularly when surface slope was greater than 10 degrees, presumably the most important range considering ankle injuries. In this higher range absolute position error was 4.23 degrees taped, and 5.53 degrees untaped (P < 0.001). Following exercise, in the higher range absolute position error was 2.5% worse when taped and 35.5% worse when untaped (P < 0.001). These data support the hypothesis that ankle taping improves proprioception before and after exercise. They also indicate that foot position awareness declines with exercise. Compared to barefoot data (position error 1.97 degrees), foot position error was 107.5% poorer with athletic footwear when untaped (absolute position error 4.11 degrees), and 58.1% worse when taped (position error 3.13 degrees). This suggests that ankle taping partly corrects impaired proprioception caused by modern athletic footwear and exercise. Footwear could be optimized to reduce the incidence of these injuries.

Pharmacological attempts to improve the bioavailability of oral etoposide

Etoposide demonstrates incomplete and variable bioavailability after oral dosing, which may be due to its concentration and pH-dependent stability in artificial gastric and intestinal fluids. The use of agents that may influence etoposide stability and, thereby, bioavailability, was investigated in a number of clinical studies. Drugs that influence the rate of gastric emptying, while modulating the time of drug absorption, did not significantly alter the etoposide area under the concentration-time curve (AUC) or bioavailability. Specifically, metoclopramide had little effect on the etoposide absorption profile and did not significantly alter the AUC (AUC with etoposide alone, 68.4 +/- 20.3 micrograms ml-1 h, versus 74.3 +/- 25.9 micrograms ml-1 h with metoclopramide), suggesting that in most patients the drug is already emptied rapidly from the stomach. In contrast, propantheline produced a dramatic effect on etoposide absorption, delaying the time of maximal concentration tmax from 1.1 to 3.5 h (P < 0.01), but again without a significant improvement in drug AUC or bioavailability across the 24-h study period (AUC with etoposide alone 78.3 +/- 19.1 micrograms ml-1 h, versus 88.1 +/- 23.6 micrograms ml-1 h with propantheline). The effect of these drugs on the absorption of oral paracetamol, a drug included in the study as a marker of gastric emptying, was exactly the same as that found for etoposide, with no change in AUC being observed after metoclopramide or propantheline administration but a significant delay in tmax being seen on co-administration with etoposide and propantheline. The co-administration of ethanol or bile salts (agents that significantly improved the stability of etoposide in artificial intestinal fluid) with oral etoposide similarly had no effect on improving the etoposide AUC or reducing the variability in AUC, suggesting that drug stability in vivo was not affected by these agents. In the third study the co-administration of cimetidine had no effect on the pharmacokinetics of oral or i.v. etoposide, despite the previous observation that etoposide stability was markedly improved at pH 3-5 as compared with pH 1 in artificial gastric fluid. This series of studies, designed to investigate factors that improved etoposide stability in laboratory studies, failed to demonstrate any potentially useful improvement in AUC or bioavailability in the clinical setting.

Proprioception and stability: foot position awareness as a function of age and footwear

We examined the hypothesis that awareness of foot position in terms of the slope of the weight-bearing surface declines with age. We further postulated that the decline would be due to a change in plantar tactile sensibility, and that footwear would further impair position judgments. We compared 15 men aged over 65 years (mean age 73) with 36 men aged under 40 (mean age 30) in terms of estimates of amplitude and direction of surface slopes. We employed a ratio scale of 0-10 representing actual slopes of 0 degrees-25 degrees in increments of 2.5 degrees. In order to examine whether subjects overestimated high angles they were told that the scale ranged from 0 to 15. We found significant differences between the two groups in terms of estimates and the effect of footwear. Psychophysical functions for estimate of slope were 0.95 for the young when barefoot and 0.71 when shod compared with 0.80 and 0.81 respectively for the older men. We conclude that sensitivity to foot position declines with age, mainly owing to loss of plantar tactile sensitivity. Footwear impairs foot position awareness in both young and old. Loss of foot position awareness may contribute to the frequency of falls in later life.

Athletic footwear affects balance in men

Stable equilibrium during locomotion is required for both superior performance of sports and prevention of injuries from falls. A recent report indicated that currently available athletic footwear impairs stability in older men. Since this discovery, if confirmed, seems important to both competitive athletes and the physically active general public, we performed an experiment using similar methods on a younger population. We tested the hypothesis that midsole thickness is negatively, and hardness positively related to dynamic equilibrium, in 17 healthy adult men (mean(s.d.) age 33(11.13) years) via a balance beam method. Subjects walked along a 9-m long beam at 0.5 m s-1 once barefoot and six times wearing identical pairs of experimental shoes which differed only in midsole hardness and thickness which spanned the respective ranges currently available in footwear. Falls from the beam (balance failures) were quantified. Balance failures varied significantly in relation to midsole hardness and thickness, and there was a strong trend toward interaction of these variables (P = 0.09). Midsole hardness was positively related to stability, and midsole thickness was negatively related, which confirms the previous report. Hence, shoes with thick-soft soles, similar to modern athletic footwear and 'walking shoes', destabilize men, and shoes with thin-hard soles provide superior stability. The pair with the poorest stability (A 15-thick; 12.34 balance failures per 100 m) produced 217% more balance failures than those associated with the best stability (A 50-thin; 3.89 balance failures per 100 m). Since most types of athletic footwear and many other shoes incorporate midsoles with hardness and thickness associated with poor stability, we conclude that both athletic performance and public safety could be enhanced through stability optimized footwear.