Impacts of metal mining on river systems: a global assessment

An estimated 23 million people live on floodplains affected by potentially dangerous concentrations of toxic waste derived from past and present metal mining activity. We analyzed the global dimensions of this hazard, particularly in regard to lead, zinc, copper, and arsenic, using a georeferenced global database detailing all known metal mining sites and intact and failed tailings storage facilities. We then used process-based and empirically tested modeling to produce a global assessment of metal mining contamination in river systems and the numbers of human populations and livestock exposed. Worldwide, metal mines affect 479,200 kilometers of river channels and 164,000 square kilometers of floodplains. The number of people exposed to contamination sourced from long-term discharge of mining waste into rivers is almost 50 times greater than the number directly affected by tailings dam failures.

Mobile App to Enhance Patient Activation and Patient-Provider Communication in Major Depressive Disorder Management: Collaborative, Randomized Controlled Pilot Study

BACKGROUND

Enhanced patient-provider engagement can improve patient health outcomes in chronic conditions, including major depressive disorder (MDD).

OBJECTIVE

We evaluated the impact of a digitally enabled care mobile app, Pathway, designed to improve MDD patient-provider engagement. Patients used a mobile interface to assess treatment progress and share this information with primary care providers (PCPs).

METHODS

In this 52-week, real-world effectiveness and feasibility study conducted in primary care clinics, 40 patients with MDD who were recently prescribed antidepressant monotherapy were randomized to use a mobile app with usual care (20/40, 50%) or usual care alone (20/40, 50%). Patients in the app arm engaged with the app daily for 18 weeks; a report was generated at 6-week intervals and shared with the PCPs to facilitate shared treatment decision-making discussions. The patients discontinued the app at week 18 and were followed through year 1. Coprimary outcome measures, assessed via research visits, included change from baseline in the 13-item Patient Activation Measure (PAM-13) and 7-item Patient-Provider Engagement Scale scores at week 18. Additional outcome measures included depression severity (9-item Patient Health Questionnaire [PHQ-9]) and cognitive symptoms (5-item Perceived Deficits Questionnaire-Depression).

RESULTS

All 37 patients (app arm: n=18, 49%; usual care arm: n=19, 51%) who completed the 18-week follow-up period (n=31, 84% female, mean age 36, SD 11.3 years) had moderate to moderately severe depression. Improvements in PAM-13 and PHQ-9 scores were observed in both arms. Increases in PAM-13 scores from baseline to 18 weeks were numerically greater in the app arm than in the usual care arm (mean 10.5, SD 13.2 vs mean 8.8, SD 9.4; P=.65). At 52 weeks, differences in PAM-13 scores from baseline demonstrated significantly greater improvements in the app arm than in the usual care arm (mean 20.2, SD 17.7 vs mean 1.6, SD 14.2; P=.04). Compared with baseline, PHQ-9 scores decreased in both the app arm and the usual care arm at 18 weeks (mean 7.8, SD 7.2 vs mean 7.0, SD 6.5; P=.73) and 52 weeks (mean 9.5, SD 4.0 vs mean 4.7, SD 6.0; P=.07). Improvements in 7-item Patient-Provider Engagement Scale and WHO-5 scores were observed in both arms at 18 weeks and were sustained through 52 weeks in the app arm. Improvements in WHO-5 scores at 52 weeks were significantly greater in the app arm than in the usual care arm (41.5 vs 20.0; P=.02).

CONCLUSIONS

Patients with MDD will engage with a mobile app designed to track treatment and disease progression. PCPs will use the data generated as part of their assessment to inform clinical care. The study results suggest that an app-enabled clinical care pathway may enhance patient activation and benefit MDD management.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03242213; https://clinicaltrials.gov/ct2/show/NCT03242213.

Reconsidering the efficiency of grazing exclusion using fences on the Tibetan Plateau

Grazing exclusion using fences is a key policy being applied by the Chinese government to rehabilitate degraded grasslands on the Tibetan Plateau (TP) and elsewhere. However, there is a limited understanding of the effects of grazing exclusion on alpine ecosystem functions and services and its impacts on herders' livelihoods. Our meta-analyses and questionnaire-based surveys revealed that grazing exclusion with fences was effective in promoting aboveground vegetation growth for up to four years in degraded alpine meadows and for up to eight years in the alpine steppes of the TP. Longer-term fencing did not bring any ecological and economic benefits. We also found that fencing hindered wildlife movement, increased grazing pressure in unfenced areas, lowered the satisfaction of herders, and rendered substantial financial costs to both regional and national governments. We recommend that traditional free grazing should be encouraged if applicable, short-term fencing (for 4-8 years) should be adopted in severely degraded grasslands, and fencing should be avoided in key wildlife habitat areas, especially the protected large mammal species.

Refining China’s grassland policies: an interdisciplinary and ex-ante analysis

China is about to embark on a new round of grassland policies as part of its 14th Five-Year-Plan. Although current grassland policies have generally been perceived positively in arresting widespread grassland degradation, concerns have arisen that the current policies may not be effective in achieving the desired reduction in livestock numbers. Furthermore, there are concerns the incentive-based payments that are part of these policy programs may not reflect herder opportunity costs or the marginal environmental benefits of the program, with associated issues of herder satisfaction and compliance. Changes to current policy settings are being considered in response to these concerns. This paper reports on an interdisciplinary and ex-ante analysis of alternative policy settings affecting grazing and livestock management in terms of their environmental impacts, net social benefits and other impacts. The analysis finds that a bundle of instruments involving both positive and negative herder incentives is needed if desired stocking rates are to be achieved. The impact on herder incomes, both positive and negative depending on the grassland biome, along with transaction costs of implementing the policies, have the most influence on net social benefits.

Optimising grazing for livestock production and environmental benefits in Chinese grasslands

Overgrazing has extensively degraded Chinese grasslands. A reduction in stocking rate of 30–50% below the district averages is required to increase the profitability of livestock production and protect vital ecosystem services such as mitigation of greenhouse gases (GHG). Grazing experiments located in the desert steppe, typical steppe and alpine meadow verified the influence of stocking rate and grazing management on livestock production, grassland composition and associated ecosystem services. The desert steppe experiment found lower stocking rates of ~150 SE (where SE is sheep equivalent, which is a 50kg animal) grazing days ha–1 (1 SE ha–1 over 150 days) enhanced botanical composition, maintained profitable lamb growth rates and reduced GHG emissions intensity. The typical steppe experiment found moderate grazing pressure of ~400 SE grazing days ha–1 (4 SE ha–1 over 100 days) maintained higher lamb growth rates, an average herbage mass >0.5t DM ha–1 that maintained the content of Leymus chinensis above 70% and Artemisia frigida below 10% of the grassland and had the highest level of net carbon sequestration. In the alpine meadow experiment the district average stocking rate of ~16 SE ha–1 (1440 SE grazing days ha–1 over 90 days) was not too high, but extending grazing into the non-growing season had no benefit. The findings of these experiments highlight that many of the benefits to ecosystem services can be achieved with reduced stocking rates which also generate profitable levels of livestock production. In both the desert and typical steppe experiments, the results were optimal when the stocking rates were adjusted to maintain average herbage mass over summer above ~0.5t DM ha–1, whereas herbage mass was higher with the local, conservative stocking rates in the alpine meadow.

Using graphic warning labels to counter effects of social cues and brand imagery in cigarette advertising

Exposure to cigarette advertising can increase the likelihood of youth smoking initiation and may encourage people who already smoke to continue. Requiring prominent, graphic warning labels could reduce these effects. We test whether graphic versus text-only warning labels in cigarette advertisements influence cognitive and emotional factors associated with youth susceptibility to smoking and adult intentions to quit. We conducted two randomized, between-subjects experiments with middle-school youth (n = 474) and adult smokers (n = 451). Both studies employed a two (graphic or text-only warnings) by two (advertisements with social cues or brand imagery) factorial design with a fifth, offset control group (social cue advertisements with the current US Surgeon General's Warning). Graphic warnings outperformed text-only warnings in reducing visual attention to the advertisement, generating visual attention to the warning and arousing more negative affect. Graphic warnings also reduced the appeal of cigarette brands among youth relative to social cue advertisements with the Surgeon General's warnings. None of the warnings (graphic or textual) influenced health risk beliefs. Graphic warning labels on cigarette advertisements appear to have effects similar to those observed on cigarette packs in previous work, with an added benefit of reducing cigarette brand appeal among youth.

Timing of the reticular lamina and basilar membrane vibration in living gerbil cochleae

Auditory sensory outer hair cells are thought to amplify sound-induced basilar membrane vibration through a feedback mechanism to enhance hearing sensitivity. For optimal amplification, the outer hair cell-generated force must act on the basilar membrane at an appropriate time at every cycle. However, the temporal relationship between the outer hair cell-driven reticular lamina vibration and the basilar membrane vibration remains unclear. By measuring sub-nanometer vibrations directly from outer hair cells using a custom-built heterodyne low-coherence interferometer, we demonstrate in living gerbil cochleae that the reticular lamina vibration occurs after, not before, the basilar membrane vibration. Both tone- and click-induced responses indicate that the reticular lamina and basilar membrane vibrate in opposite directions at the cochlear base and they oscillate in phase near the best-frequency location. Our results suggest that outer hair cells enhance hearing sensitivity through a global hydromechanical mechanism, rather than through a local mechanical feedback as commonly supposed.

What is the quietest sound the ear can detect? All sounds begin as vibrating air molecules, which enter the ear and cause the eardrum to vibrate. We can detect vibrations that move the eardrum by a distance of less than one picometer. That’s one thousandth of a nanometer, or about 100 times smaller than a hydrogen atom. But how does the ear achieve this level of sensitivity?

Vibrations of the eardrum cause three small bones within the middle ear to vibrate. The vibrations then spread to the cochlea, a fluid-filled spiral structure in the inner ear. Tiny hair cells lining the cochlea move as a result of the vibrations. There are two types of hair cells: inner and outer. Outer hair cells amplify the vibrations. It is this amplification that enables us to detect such small movements of the eardrum. Inner hair cells then convert the amplified vibrations into electrical signals, which travel via the auditory nerve to the brain.

The bases of outer hair cells are connected to a structure called the basilar membrane, while their tops are anchored to a structure called the reticular lamina. It was generally assumed that outer hair cells amplify vibrations of the basilar membrane via a local positive feedback mechanism that requires the hair cells to vibrate first. But by comparing the timing of reticular lamina and basilar membrane vibrations in gerbils, He et al. show that this is not the case. Outer hair cells vibrate after the basilar membrane, not before. This indicates that outer hair cells use a mechanism other than commonly assumed local feedback to amplify sounds.

The results presented by He et al. change our understanding of how the cochlea works, and may help bioengineers to design better hearing aids and cochlea implants. Millions of patients worldwide who suffer from hearing loss may ultimately stand to benefit.

Effects of shed modifications on ewe reproductive performance and lamb growth rate in Inner Mongolia

The effects of warm sheds on the performance of ewes and their lambs in winter are poorly understood. The aim of the present study was to examine the effects of traditional sheds (TS + grazing) and modified warm sheds (WS, no grazing) on the reproductive performance of ewes (as well as their liveweight) and their lambs during the winter–spring period. Cross-bred ewes (n = 120) were randomly assigned to two treatments, either TS (+ grazing) or WS (no grazing), during the winter–spring period of 2011, 2012 and 2013. This study was conducted on two adjacent farms with the two treatments applied on each. The ewes in the TS treatment were grazed continuously on pasture in the day and housed in traditional sheds each evening, whereas the ewes in the WS treatment were not grazed. The animals in each treatment were fed the same amount of feed. Ewes housed in the WS group had a higher liveweight and lower weight loss than ewes in the TS group (P = 0.004 and 0.005 respectively); over the 3 years, the weight loss of the ewes in both groups was worst in the first 2 months (December–January) compared with the later 2 months, and was significantly alleviated after the first year (2011; P < 0.001). Lamb liveweight and gain were higher in the WS than TS treatment group (P < 0.001) and the growth rates of the lambs increased continuously as shed temperatures increased. Lamb weight gain and birthweight increased significantly with increasing years of the experiment (P < 0.001). There were more lambs born in the WS than in the TS groups (P = 0.020), with higher survival and twinning rates (P < 0.05). As shed temperatures increased, lambing, survival and twinning rates increased continuously. Therefore, keeping livestock in warm sheds during the winter and spring period will lift animal productivity, leading to improved household incomes. Elimination of winter grazing will reduce damage to already degraded grasslands and will assist herders to develop more positive attitudes towards animal production enterprises.

Bipolar CHOICE (Clinical Health Outcomes Initiative in Comparative Effectiveness): a pragmatic 6-month trial of lithium versus quetiapine for bipolar disorder

BACKGROUND

Bipolar disorder is among the 10 most disabling medical conditions worldwide. While lithium has been used extensively for bipolar disorder since the 1970s, second-generation antipsychotics (SGAs) have supplanted lithium since 1998. To date, no randomized comparative-effectiveness study has compared lithium and any SGA.

METHOD

Within the duration of the study (September 2010-September 2013), participants with bipolar I or II disorder (DSM-IV-TR) were randomized for 6 months to receive lithium (n = 240) or quetiapine (n = 242). Lithium and quetiapine were combined with other medications for bipolar disorder consistent with typical clinical practice (adjunctive personalized treatment [APT], excluding any SGA for the lithium + APT group and excluding lithium or any other SGA for the quetiapine + APT group). Coprimary outcome measures included Clinical Global Impressions-Efficacy Index (CGI-EI) and necessary clinical adjustments, which measured number of changes in adjunctive personalized treatment. Secondary measures included a full range of symptoms, cardiovascular risk, functioning, quality of life, suicidal ideation and behavior, and adverse events.

RESULTS

Participants improved across all measures, and over 20% had a sustained response. Primary (CGI-EI, P = .59; necessary clinical adjustments, P = .15) and secondary outcome changes were not statistically significantly different between the 2 groups. For participants with greater manic/hypomanic symptoms, CGI-EI changes were significantly more favorable with quetiapine + APT (P = .02). Among those with anxiety, the lithium + APT group had fewer necessary clinical adjustments per month (P = .02). Lithium was better tolerated than quetiapine in terms of the burden of side effects frequency (P = .05), intensity (P = .01), and impairment (P = .01).

CONCLUSIONS

Despite adequate power to detect clinically meaningful differences, we found outcomes with lithium + APT and quetiapine + APT were not significantly different across 6 months of treatment for bipolar disorder.

TRIAL REGISTRATION

ClinicalTrials.gov identifier for the Bipolar CHOICE study: NCT01331304.

Psychotherapy use in bipolar disorder: Association with functioning and illness severity

OBJECTIVE

This study examines characteristics of individuals with bipolar disorder who sought psychotherapy versus those who did not.

METHODS

Bipolar CHOICE was an 11-site comparative effectiveness study of lithium versus quetiapine in symptomatic outpatients (N = 482) with bipolar disorder. At baseline, participants' psychotherapy use within the past 3 months, mood, functioning, and overall health were assessed. Logistic regressions were used to test whether psychotherapy users and non-users differed on various demographic and clinical variables at baseline. Mixed-effects regression was used to determine whether psychotherapy groups differed on response to treatment over the 6-month study. Kaplan-Meier plots and log-rank tests were employed to test whether there were any differences in time to recovery (CGI-BP ≤ 2 for at least 8 weeks) between the groups.

RESULTS

Thirty one percent of participants reported using psychotherapy services. Psychotherapy users reported greater medication side effect burden than non-users and were more likely to have moderate to high suicide risk and at least one anxiety disorder. Participants not utilizing medications or psychotherapy had greater mania symptom severity, were younger, and less educated than medication only users. Medication only users were more likely to be married than the other participants.

CONCLUSIONS

These data suggest that a minority of individuals with bipolar disorder attend psychotherapy services, and those that do have greater illness burden.

Scabies: important clinical consequences explained by new molecular studies

In 2004, we reviewed the status of disease caused by the scabies mite Sarcoptes scabiei at the time and pointed out that very little basic research had ever been done. The reason for this was largely the lack of availability of mites for experimental purposes and, to a degree, a consequent lack of understanding of its importance, resulting in the trivial name 'itch mite'. Scabies is responsible for major morbidity in disadvantaged communities and immunocompromised patients worldwide. In addition to the physical discomfort caused by the disease, scabies infestations facilitate infection by bacterial pathogens such as Streptococcus pyogenes and Staphylococcus aureus via skin lesions, resulting in severe downstream disease such as in a high prevalence of rheumatic fever/heart disease in affected communities. We now have further evidence that in disadvantaged populations living in tropical climates, scabies rather than 'Strep throat' is an important source of S. pyogenes causing rheumatic fever and eventually rheumatic heart disease. In addition, our work has resulted in two fundamental research tools that facilitate much of the current biomedical research efforts on scabies, namely a public database containing ~45,000 scabies mite expressed sequence tags and a porcine in vivo model. Here we will discuss novel and unexpected proteins encountered in the database that appear crucial to mite survival with regard to digestion and evasion of host defence. The mode(s) of action of some of these have been at least partially revealed. Further, newly discovered molecules that may well have a similar role, such as a family of inactivated cysteine proteases, are yet to be investigated. Hence, there are now whole families of potential targets for chemical inhibitors of S. scabiei. These efforts put today's scabies research in a unique position to design and test small molecules that may specifically interfere with mite-derived molecules, such as digestive proteases and mite complement inhibitors. The porcine scabies model will be available to trial in vivo treatment with potential inhibitors. New therapies for scabies may be developed from these studies and may contribute to reduce the spread of scabies and the subsequent prevalence of bacterial skin infections and their devastating sequelae in the community.

Aminoglycoside antibiotics cochleotoxicity in paediatric cystic fibrosis (CF) patients: A study using extended high-frequency audiometry and distortion product otoacoustic emissions

Despite known ototoxic effects of aminoglycoside (AG) antibiotics, audiological assessment is not routinely undertaken in UK CF patients. Consequently, the incidence of hearing loss is not well established.

OBJECTIVE

To document the incidence of hearing loss in cystic fibrosis (CF) children.

DESIGN

Hearing function of 45 children from Great Ormond Street Hospital was assessed using pure-tone audiometry up to 20kHz and DPOAEs up to 8kHz.

STUDY SAMPLE

39/45 of participants had received intravenous (IV) AGs, 23 of which received repeated IV AGs every 3 months.

RESULTS

In this high exposure group, 8 (21%) had clear signs of ototoxicity; average 8-20kHz thresholds were elevated by ∼50dB and DPOAE amplitudes were >10dB lower at f2 3.2-6.3 kHz. The remaining 31/39 (79%) of AG exposed patients had normal, even exceptionally good hearing. The 21% incidence of ototoxicity we observed is substantial and higher than previously reported. However, our finding of normal hearing in children with equal AG exposure strongly suggests that other unknown factors, possibly genetic susceptibility, influence this outcome.

CONCLUSIONS

We recommend comparable auditory testing in all CF patients with high AG exposures. Genetic analysis may help explain the dichotomy in response to AGs found.

Identification of a dieldrin resistance-associated mutation in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

The southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae), is a major vector of tick fever organisms affecting cattle in many parts of the world, including Australia, Africa, and South America. Control of the southern cattle tick through acaricide use is an important approach in disease management. Resistance has emerged to many of the acaricides currently and previously used, including the cyclodienes. Although cyclodiene resistance mechanisms have been characterized in many insect species, this report is the first to identify mutations associated with dieldrin resistance in the cattle tick. A novel two base pair mutation in the GABA-gated chloride channel gene has been identified at position 868-9 and causes a codon change from threonine to leucine. Analysis of a small number of field-collected samples resistant to dieldrin shows this mutation has been maintained without selection pressure since the withdrawal of dieldrin in Australia > 20 yr ago. The mutation is not found in other laboratory-maintained strains of R. microplus that were subject to selection pressure with various acaricides.

High-energy 13.9 nm table-top soft-x-ray laser at 2.5 Hz repetition rate excited by a slab-pumped Ti:sapphire laser

We have demonstrated repetitive operation of a table-top lambda=13.9 nm Ni-like Ag soft-x-ray laser that generates laser pulses with 10 microJ energy. The soft-x-ray laser is enabled by a Ti:sapphire laser pumped by high-repetition-rate frequency-doubled high-energy Nd:glass slab amplifiers. Soft-x-ray laser operation at 2.5 Hz repetition rate resulted in 20 microwatt average power.

Inhibition of vascular endothelial growth factor receptor tyrosine kinases impairs adipose tissue development in mouse models of obesity

We have studied the effect of PTK787 (Vatalanib), an inhibitor of vascular endothelial growth factor receptor (VEGFR) tyrosine kinases, on adipose tissue development. Oral administration of PTK787 for 4 weeks (2 mg/g high fat diet, HFD) to C57Bl/6 mice resulted in a significant reduction in total body weight and of subcutaneous (SC) and gonadal (GON) adipose tissue mass, as compared to control animals fed HFD only (all p<0.0005). In the GON adipose tissue adipocytes were hypertrophic after PTK787 treatment. Blood vessel size and density were not significantly affected by PTK787 treatment. Expression of Flk-1 (VEGFR-2) mRNA was significantly reduced in SC and GON adipose tissues of PTK787 treated mice. De novo fat pad formation following injection of preadipocytes in NUDE mice was significantly (p<0.005) impaired by PTK787 administration (2 mg/g HFD for 4 weeks), without associated effect on blood vessel size or density. Thus, in nutritionally induced murine obesity models, oral administration of the VEGFR tyrosine kinases inhibitor PTK787 resulted in reduced adipose tissue development.

Acaricide rotation strategy for managing resistance in the tick Rhipicephalus (Boophilus) microplus (Acarina: Ixodidae): laboratory experiment with a field strain from Costa Rica

During the past two decades, resistance to pyrethroids within the cattle tick genus Boophilus has caused tick control problems in various tropical countries, mainly in Latin America, southern Africa, Australia, and New Caledonia. A Rhipicephalus (Boophilus) microplus (Canestrini) strain from Costa Rica, exhibiting resistance to the pyrethroid deltamethrin but only a very low resistance to organophosphates (OP) was kept under selection pressure for 9 to 11 generations by using deltamethrin or coumaphos (OP), either exclusively or in rotation. The objective of this acaricide rotation was to examine the possibility of delaying or reducing the full emergence of pyrethroid resistance. In the substrain selected with deltamethrin at the LD50 concentration, resistance to deltamethrin was measured after five generations (resistance factor [RF] = 9.2) and very high resistance after 11 generations (RF = 756), compared with the starting field strain from Costa Rica. In the substrain selected with deltamethrin then coumaphos in rotation, resistance to deltamethrin was variable from one generation to the next (RF = 1-4.2), but no high, stable resistance developed. After 10 generations of rotation, the deltamethrin RF was 1.6. In the substrains selected continuously with coumaphos or coumaphos and deltamethrin in rotation, no consistent change in resistance to coumaphos was observed. Rotation of deltamethrin with coumaphos seems to delay the development of strong resistance to deltamethrin in a population that had initially a low level of deltamethrin resistance.

Gene expression profiling of Hereford Shorthorn cattle following challenge with Boophilus microplus tick larvae

The ability of cattle to resist tick infestations is partly genetically determined. In order to better define the nature of Bos taurus resistance to the cattle tick Boophilus microplus, skin gene expression was studied using a cattle skin derived cDNA microarray. Expression profiles were determined in skin biopsies sampled from three highly tick resistant animals (HR) and two animals with lower tick resistance (LR) at time 0, immediately before challenge, and again 24 h after challenge. The analysis of the resulting expression data addressed two biological questions: first, for any animal exposed to ticks, which genes are differentially expressed in the 24 h following challenge; and second, which genes are differentially expressed between animals of high and low resistance at 24 h after challenge? In total, 214 genes were found to be differentially expressed in response to larval challenge across all the animals. Seventy-two genes were upregulated and 76 were downregulated at 24 h after challenge. Genes with significantly altered gene expression levels following tick infestation were predominantly keratin genes or mitochondrial genes, as well as odorant binding protein (OBP) and Bos taurus major allergen BDA20. In addition, we identified 66 genes with differential expression between HR and LR animals at 24 h. Of these, genes representing the extracellular matrix and immunoglobulin gene expression pathways were overrepresented. Three differentially expressed genes, OBP, Bos taurus major allergen BDA20 and dendritic cell protein HFL-B5 were further analysed by quantitative reverse transcription PCR (qRT-PCR). The qRT-PCR assay results closely mirrored the expression profiles found in the microarray experiment.

Percutaneous coronary interventions in a rural hospital without surgical backup: report of one year of experience

This paper demonstrates that percutaneous coronary intervention (PCI) can be provided in a rural setting with results that are at least as good as the national average without untoward risk to the patient. Percutaneous coronary intervention is the initial treatment of choice for acute myocardial infarction (AMI). Historically, PCI has been available in metropolitan areas, yet 20% of the population lives in rural areas. Rural patients with AMI may not be receiving optimal care, especially if PCI is not readily available. In a rural setting, door-to-balloon time for patients with acute ST-elevation MI was 67.66 +/- 30.80 min. This is significantly better than the 186 min reported in the National Registry Myocardial Infarction (NRMI). These results were achieved with a complication rate that was not significantly different from national averages. This study demonstrates that PCI can be provided safely and with good results in a rural setting.

World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of acaricides against ticks (Ixodidae) on ruminants

These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of acaricides (excluding vaccines and other bio-control agents) against single and multi-host ticks (Ixodidae) on ruminants. Information is provided on the selection of animals, dose determination, dose confirmation and field studies, record keeping and result interpretation. The use of pen facilities is advocated for dose determination and confirmation studies for defining therapeutic and persistent efficacy. A minimum of two studies per tick species for which claims are sought is recommended for each dose determination and dose confirmation investigation. If dose confirmation studies demonstrate greater than 95% efficacy the sponsor may proceed to field studies, where a minimum of two studies per geographical location is preferred to confirm the therapeutic and persistent efficacy under field conditions. If dose confirmation studies demonstrate less than 95% efficacy then longer-term field studies can be conducted over two tick seasons with a minimum of two studies per geographical location. These studies can incorporate other control methods such as tick vaccines, to demonstrate stable long-term tick management. Specific advice is also given on conducting studies with paralysis ticks. These guidelines are also intended to assist investigators on how to conduct specific experiments, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new acaricides, and to facilitate the worldwide adoption of standard procedures.

Characterization of a new Bacillus thuringiensis endotoxin, Cry47Aa, from strains that are toxic to the Australian sheep blowfly, Lucilia cuprina

Sixteen isolates of Bacillus thuringiensis, derived from various soil samples collected in Australia, are highly toxic to larvae of the sheep blowfly (Lucilia cuprina). The toxin gene from one of the strains (CAA890) was cloned by genome walking, and sequencing of the cloned fragments revealed a new cry gene, encoding a protein of 1134 amino acid residues, with a theoretical molecular mass of 139,209Da. Based on the amino acid sequence comparison with known Cry delta-endotoxins, the gene was designated cry47Aa. Homology modelling based on known crystal structures of the Cry toxins reveals the differences to be located in the loops of domain II in the putative toxin-receptor binding surfaces between Cry47Aa and the dipteran active Cry2Aa. We also showed that the cry47Aa gene is present in the other isolates that are highly toxic to the sheep blowfly.

The mitochondrial 12S gene is a suitable marker of populations of Sarcoptes scabiei from wombats, dogs and humans in Australia

We sequenced part of the mitochondrial 12S ribosomal RNA gene of 23 specimens of Sarcoptes scabiei from eight wombats, one dog and three humans. Twelve of the 326 nucleotide positions varied among these mites and there were nine haplotypes (sequences) that differed by 1-8 nucleotides. Phylogenetic analyses indicated that these mites were from two lineages: (1) mites from wombats from Victoria, Australia, and mites from the humans and dog from the Northern Territory, Australia (haplotypes 1-4, 9); and (2) mites from the humans and dog from the Northern Territory (haplotypes 5-8). Mites from the three different hosts (wombats, a dog and humans) had not diverged phylogenetically; rather, these mites had similar 12S sequences. Thus, we conclude that these mites from wombats, humans and a dog are closely related, and that they diverged from a common ancestor relatively recently. This conclusion is consistent with the argument that people and/or their dogs introduced to Australia the S. scabiei mites that infect wombats in Australia . So, S. scabiei, which has been blamed for the extinction of populations of wombats in Australia, may be a parasitic mite that was introduced to Australia with people and/or their dogs. These data show that the mitochondrial 12S rRNA gene may be a suitable population marker of S. scabiei from wombats, dogs and humans in Australia.

Reduced oviposition of Boophilus microplus feeding on sheep vaccinated with vitellin

The most abundant protein present in Boophilus microplus eggs, vitellin, was isolated and purified as a non-covalent complex of six glyco-polypeptides of Mr 44-107kDa. The protein complex bound haem. Immuno-blots demonstrated that antibodies raised to vitellin recognised a 200kDa polypeptide in the haemolymph of adult female ticks. This is consistent with the general proposal that in arthropods vitellin is derived by proteolytic processing from a large precursor protein, vitellogenin. In parallel with this study, an 80kDa glycoprotein (GP80) was independently purified from larvae of B. microplus using efficacy in vaccination trials as an assay. Antibodies to GP80 also recognised a 200kDa protein in the haemolymph of ticks and a major 87kDa polypeptide present in the vitellin complex. Conversely, antibodies to purified vitellin recognised GP80. The amino-terminal amino acid sequences of the 87kDa vitellin polypeptide and GP80 were identical for at least the first 11 residues and internal peptide sequences from both polypeptides were co-located in a single but incomplete deduced amino sequence of B. microplus vitellogenin. Thus, GP80 is a processed product from vitellogenin and highly related to but not completely identical with the 87kDa vitellin polypeptide. Vaccination trials in the model host sheep were performed with purified vitellin and GP80. Sheep vaccinated with either purified vitellin or GP80 returned significantly reduced numbers of engorged female ticks with decreased weights and reduced oviposition. In contrast, sheep vaccinated with recombinant hexahis-GP80, which was incorrectly folded and not glycosylated showed no significant effects on ticks. It was concluded that vitellin and GP80 could induce immune responses that partially protect sheep from the tick, B. microplus. However, critical protective epitopes are associated with the folding of the protein and/or the oligosaccharides attached to it.

NK cells are essential for effective BCG immunotherapy

Adjuvant intravesical bacillus Calmette-Guérin (BCG) therapy is a well-established and successful adjuvant immunotherapy in the treatment of superficial bladder cancer. Although the function of natural killer (NK) cells in other immunotherapeutic regimens (e.g., lymphokine-activated killer [LAK] cell or interleukin-2 [IL-2] therapy) has been established, the contribution of NK cells to effective BCG immunotherapy is not clear. We used a human in vitro system to analyze the role of NK cells in BCG-induced cellular cytotoxicity. After stimulation of mononuclear cells with BCG for 7 days, these BCG-activated killer (BAK) cells displayed substantial cytotoxicity against bladder tumor cells. Magnetic depletion experiments and fluorescence activated cell sorting revealed that NK cells were the major effector cell population. To address NK cell function in vivo, we studied a syngeneic orthotopic murine bladder cancer model and compared BCG immunotherapy in C57BL/6 wild-type mice, NK-deficient beige mice and mice treated with anti-NK1.1 monoclonal antibody. Four weekly instillations of viable BCG significantly prolonged survival in wild-type mice compared with control mice treated with solvent alone. In contrast, BCG therapy was completely ineffective in NK-deficient beige mice and in mice treated with anti-NK1.1 monoclonal antibody. These findings suggest a key role for NK cells during BCG immunotherapy.

Peritrophins of adult dipteran ectoparasites and their evaluation as vaccine antigens

Several peritrophins of larvae of Lucilia cuprina (sheep blowfly) have demonstrated potential as vaccine antigens, and some have been characterised and cloned. These proteins are tightly associated with the peritrophic matrix, a chitinous tube or sac lining the lumen of the gut of most insects. The peritrophins require strong denaturants for their removal from peritrophic matrix. We now report the preliminary characterisation of peritrophins of the adult stage of L. cuprina and Haematobia irritans exigua (buffalo fly). Similar SDS-PAGE profiles were obtained for proteins extracted in SDS or urea from isolated adult peritrophic matrices of both species. Radioiodination of urea-extracted peritrophins improved sensitivity, indicating numerous proteins of 15-75 kDa. Direct radioiodination of L. cuprina peritrophic matrix preferentially labelled high molecular weight complexes and proteins of 80-90 kDa. Two-dimensional gel analyses of a urea extract of adult L. cuprina peritrophic matrix revealed that most proteins were moderately acidic. Antibodies produced against SDS-extracted peritrophins, or against sonicated peritrophic matrices of these two flies were crossreactive. The sera also appeared to recognise SDS-extracted components of Triton X-100 treated and washed adult peritrophic matrix of the mosquito, Aedes vigilax (Skause). This profile altered as the peritrophic matrix matured. In concordance with extracts from the adult L. cuprina and H.i. exigua peritrophic matrices, proteins in the 50-75 kDa region were immunodominant. The vaccine potential of the peritrophins of these Diptera were examined following vaccination of cattle and rabbits with adult H.i. exigua or L. cuprina peritrophins. When the adult life stages of H.i. exigua or two mosquitoes, A. vigilax and A. aegypti (Linnaeus), were fed on the sera or blood of vaccinated hosts, there were no detrimental effects to any life cycle stages of these Diptera.

Immunological aspects of nutritional diabetes prevention in NOD mice: a pilot study for the cow's milk-based IDDM prevention trial

Human epidemiological studies delineated early exposure to intact dietary protein (e.g., most infant formulas) as an environmental risk factor for the development of IDDM. The Trial to Reduce IDDM in the Genetically at Risk (TRIGR), an international IDDM prevention trial, has been designed to determine if avoidance of intact dairy protein in high-risk infants < or =6 months of age can reduce the subsequent diabetes incidence. We here studied the casein hydrolysate-based trial diet (Nutramigen) in NOD mice. When given either continuously or for 10 weeks after weaning, the test diet was highly effective in preventing autoimmune diabetes (32-week incidence: 4.6 vs. 58.8%) and in preserving pancreatic insulin levels, with little effect on islet inflammation. Spleen cells from protected NOD mice failed to adoptively transfer diabetes into irradiated syngeneic recipients. When co-transferred with splenocytes from diabetic donors, cells from diet-protected mice inhibited adoptive diabetes transfer (incidence 50 vs. 94%, P < 0.001). T-cell reactivity to the islet cell autoantigens ICA69 (islet cell antigen 69) and GAD65 developed only in diabetic recipients of spleen cell grafts, indicating that diabetes protection extends to more than one autoantigen. In protected mice, ICA69 T-cell reactivity was not detectable spontaneously nor after priming with this autoantigen; however, priming with the cross-reactive non-self-antigen bovine serum albumin recruited T-cells responsive to ICA69. Thus, diabetes prevention with the clinical trial diet is effective in NOD mice, where it affects some T-cell repertoires and allows development of regulatory cells that interfere with destructive autoimmunity.

Cloning and characterisation of angiotensin-converting enzyme from the dipteran species, Haematobia irritans exigua, and its expression in the maturing male reproductive system

The angiotensin-converting enzymes (ACE) are involved in the regulation of the specific maturation or degradation of a number of mammalian bioactive peptides. A carboxydipeptidase similar to mammalian ACE has now been identified in the adult stage of the haematophagous fly, Haematobia irritans exigua (buffalo fly), a close relative of the horn fly of North America. The enzyme was purified by lectin-affinity chromatography and ion-exchange chromatography and migrated as a doublet of 70 kDa upon reducing SDS/PAGE. Unlike mammalian ACE, the fly carboxydipeptidase (HieACE) is not membrane bound. The amino acid sequence of an internal peptide from HieACE and a conserved amino acid region present in all mammalian ACE were used to design degenerate oligonucleotide primers suitable for PCR. A DNA fragment amplified from adult buffalo fly cDNA was used to identify a cDNA clone that encoded the enzyme. The cDNA sequence encodes a carboxydipeptidase with 41-42% amino acid identity to the mammalian testicular ACE. The active-site regions of mammalian ACE are conserved in the deduced amino acid sequence of HieACE. Enzymatically, HieACE is very similar to its mammalian counterparts, with comparable Km and V(max) values for the synthetic substrate, benzoylglycylglycylglycine, and similar patterns of inhibition by EDTA, ACE inhibitor peptide and captopril. HieACE also specifically activates angiotensin I to angiotensin II and degrades other mammalian ACE substrates such as bradykinin, substance P and cholecystokinin-8. In the adult fly, HieACE is expressed in the compound ganglion and in the posterior region of the midgut. Similar to the mammalian system, expression of this enzyme is induced in the maturing male reproductive system, which suggests conservation of ACE function in these species.

RAPD analysis of isolates of Burkholderia pseudomallei from patients with recurrent melioidosis

Twenty-seven isolates of Burholderia pseudomallei (formerly Pseudomonas pseudomallei) from ten patients with recurrent melioidosis were analysed by RAPD. In two cases RAPD patterns in recurrent isolates differed from the original isolates; one was considered a likely reinfection while the other may represent relapse from one of two strains initially infecting the patient. In two cases where a change in antibiotic resistance had occurred between original and relapse isolates, slight changes in RAPD patterns were found with one of the four primers used. In the other six cases the relapse was clearly due to the original strain re-emerging unchanged, with identical RAPD patterns with all four primers.

Subdivision of Burkholderia pseudomallei ribotypes into multiple types by random amplified polymorphic DNA analysis provides new insights into epidemiology

Ribotyping has previously been used for epidemiological studies of Burkholderia pseudomallei (previously Pseudomonas pseudomallei). We show here that random amplified polymorphic DNA (RAPD) analysis allows subdivision of strains of the same ribotype. With five different primers, no two epidemiologically unrelated isolates of any single ribotype in this study of 102 isolates from humans, goats, cats, and soil had identical RAPD patterns. Conversely, RAPD analysis showed clonality for isolates from each of two animal outbreaks of melioidosis and from a nontropical focus of animal and human melioidosis spanning 25 years. Some soil isolates were identical to epidemiologically related animal and human isolates as determined by RAPD typing. There was no evidence that the clinical outcome of melioidosis was related to RAPD patterns.

Streptokinase alleles and disease association in group A streptococci

Allele-specific oligonucleotides were used for PCR-based typing of the streptokinase locus of group A streptococcal strains, including well characterized type strains, isolates from patients with acute poststreptococcal glomerulonephritis and strains from Aboriginal communities in the Northern Territory of Australia. The streptokinase SKN allele, previously thought to be associated with glomerulonephritis, was no more frequent in nephritogenic than in non-nephritogenic streptococcal strains in this collection.

Forearm pronation and supination: reliability of absolute torques and nondominant/dominant ratios

This study examined the reliability of pronation and supination measurements expressed in absolute units (newton-meters [Nm]) and nondominant/dominant ratios (%), and determined isometrically using the BTE (WS20) and the Cybex (340) dynamometers. Twenty-one healthy men and 22 healthy women were tested twice on each machine, within 14 days. Twelve of 16 reliability coefficients for absolute torques were considered acceptable (> 0.75) when determined as the reliability of two repetitions on one occasion, while 14 of 16 coefficients were acceptable when determined as the reliability of two repetitions on each of two occasions. However, reliability coefficients for the nondominant/dominant ratios were not acceptable on one (0 of 8 coefficients > 0.75) or two (2 of 8 coefficients > 0.75) occasions. Ratio data were also characterized by larger standard errors of measurement (SEMs) and wider 95% confidence intervals, relative to the sample mean and standard deviation. Overall, reliability coefficients, SEMs, and 95% confidence intervals were similar for men and women, pronation and supination movements, and the BTE and Cybex dynamometers. The authors suggest that absolute scores be used when possible, as these data tend to provide more reliable measurements--especially when the clinician has only limited test occasions to establish baseline scores.

Sequence- and strand-specific cleavage in oligodeoxyribonucleotides and DNA containing 3'-thiothymidine

Oligonucleotides containing a 3'-thiothymidine residue (T3's) at the cleavage site for the EcoRV restriction endonuclease (between the central T and A residues of the sequence GATATC) have been prepared on an automated DNA synthesizer using 5'-O-monomethoxytritylthymidine 3'-S-(2-cyanoethyl N,N-diisopropylphosphorothioamidite). The self-complementary sequence GACGAT3'sATCGTC was completely resistant to cleavage by EcoRV, while the heteroduplex composed of 5'-TCTGAT3'sATCCTC and 5'-GAGGATATCAGA (duplex 4) was cleaved only in the unmodified strand (5'-GAGGATATCAGA). In contrast, strands containing a 3'-S-phosphorothiolate linkage could be chemically cleaved specifically at this site with Ag+. A T3's residue has also been incorporated in the (-) strand of double-stranded closed circular (RF IV) M13mp18 DNA at the cleavage site of a unique EcoRV recognition sequence by using 5'-pCGAGCTCGAT3'sATCGTAAT as a primer for polymerization on the template (+) strand of M13mp18 DNA. On treatment of this substrate with EcoRV, only one strand was cleaved to produce the RF II or nicked DNA. Taken in conjunction with the cleavage studies on the oligonucleotides, this result demonstrates that the 3'-S-phosphorothiolate linkage is resistant to scission by EcoRV. Additionally, the phosphorothiolate-containing strand of the M13mp18 DNA could be cleaved specifically at the point of modification using iodine in aqueous pyridine. The combination of enzymatic and chemical techniques provides, for the first time, a demonstrated method for the sequence-specific cleavage of either the (+) or (-) strand.

Postoperative urinary retention: Part II--A retrospective study

Postoperative urinary retention, a potential postoperative complication, can lead to discomfort and contribute to atony of bladder wall, need for catheterization and, sometimes, prolonged hospital stays. A retrospective study was conducted to analyze variables related to postoperative urinary retention. Data was collected by a chart review of 100 postoperative cases in a large Veterans Administration Medical Center. All patients were male, had a mean age of 61.1 years, and had received spinal or general anesthesia. Patients with known urologic problems, paraplegic patients, quadruplegic patients, patients undergoing procedures lasting less than 3 hours, and patients with indwelling Foley catheters were excluded. The medical review form was used to collect data from the medical records. Sixty-one percent of the patients required straight catheterization for their first postoperative urinary output. Sixty-five percent of the spinal anesthetic patients and 57% of the general anesthetic patients required straight catheterization. Orthopedic patients were the highest percentage of patients requiring catheterization. The patients who received large volumes of intravenous (IV) fluid in the operating room were more likely to be catheterized in the PACU. Determining whether physical assessment or IV volume indicated need for catheterization of these patients was difficult because documentation on the PACU record was usually incomplete. Complete documentation of assessment and intervention on the PACU record occurred 10% of the time. A need for full assessment on all postsurgical patients in the PACU and improved documentation is indicated.

Postoperative urinary retention: Part I--Overview and implications for the postanesthesia care unit nurse

Postoperative urinary retention and resulting bladder distention are common complications following surgical procedures. The PACU nurse needs a thorough understanding of bladder distention, causes, and how to assess for signs and symptoms in the PACU patient. Unrelieved bladder distention can lead to discomfort and problems with micturation or chronic urinary retention. The anatomy of the bladder, causes and factors related to bladder distention, and methods with which the PACU nurse can assess and evaluate for bladder distention are presented.

Epithelial action potentials in embryos of the Australian lungfish

The epithelial cells of the skin of embryonic Australian lungfish (Neoceratodus forsteri) between stages 30 and 39, are mechanosensitive and excitable, showing overshooting action potentials 400-800 ms long with a rapid rise followed by a slower repolarization (usually with a shoulder on the repolarizing phase), which propagate at around 10 mm s-1. This skin impulse system is very similar to that found in embryonic and larval Amphibia; the significance of this similarity is discussed.

An advanced cochlear echo technique suitable for infant screening

An advanced cochlear echo test technique has been specially developed to tackle some specific problems associated with measurements from infants. The test procedure and data processing combination has greatly improved noise immunity and has given very reliable results on poorly co-operating children. Technical details are given and the results of a study of 105 ears from 55 children are presented. The potential of the advanced technique as a screening test is discussed.

Factors distinguishing couples at risk for nondisjunction

Micronucleus frequencies were determined on 24 young parents of trisomic infants, 21 individuals with recurrent unexplained abortions, and 42 control individuals with proven reproductive success. In addition to measurements of spontaneous micronucleus frequencies, mitomycin C induced frequencies were determined at two doses (2.5 and 5.0 ng/mL). Using the 95% confidence limits established from control data as an arbitrary upper limit, 16 of 24 parents of trisomics and 5 of 21 recurrent aborters were detected by the micronucleus assay to above this cutoff. The effects of sex, age, pregnancy status, and a variety of environmental exposures were studied by comparing the micronucleus frequencies of the exposed and unexposed populations. The data suggested that vitamins were associated with a lower micronucleus frequency and tea drinking with an increased micronucleus frequency in parents of trisomics, an effect not seen in controls. These results suggest that a biologic basis for nondisjunction may be associated with elevation in spontaneous and induced micronuclei. In addition, tea and vitamins may modulate micronucleus frequencies in parents of trisomics who appear to be more sensitive to these influences than the controls.