Plant invasion impacts on fungal community structure and function depend on soil warming and nitrogen enrichment.

The impacts of invasive species on biodiversity may be mitigated or exacerbated by abiotic environmental changes. Invasive plants can restructure soil fungal communities with important implications for native biodiversity and nutrient cycling, yet fungal responses to invasion may depend on numerous anthropogenic stressors. In this study, we experimentally invaded a long-term soil warming and simulated nitrogen deposition experiment with the widespread invasive plant Alliaria petiolata (garlic mustard) and tested the responses of soil fungal communities to invasion, abiotic factors, and their interaction. We focused on the phytotoxic garlic mustard because it suppresses native mycorrhizae across forests of North America. We found that invasion in combination with warming, but not under ambient conditions or elevated nitrogen, significantly reduced soil fungal biomass and ectomycorrhizal relative abundances and increased relative abundances of general soil saprotrophs and fungal genes encoding for hydrolytic enzymes. These results suggest that warming potentially exacerbates fungal responses to plant invasion. Soils collected from uninvaded and invaded plots across eight forests spanning a 4 °C temperature gradient further demonstrated that the magnitude of fungal responses to invasion was positively correlated with mean annual temperature. Our study is one of the first empirical tests to show that the impacts of invasion on fungal communities depends on additional anthropogenic pressures and were greater in concert with warming than under elevated nitrogen or ambient conditions.

A preliminary study investigating effects of oral monensin sodium in an enteric Mycobacterium avium ssp. paratuberculosis infection model of calves.

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of Johne's disease, an enteric infection of ruminants that causes significant economic burden for dairy and beef producers. Efforts to control MAP in endemic herds typically focus on herd management practices such as limiting exposure or early culling of infected animals and, occasionally, vaccination. The ionophore monensin sodium may have protective effects against MAP both in vivo and in vitro; however, this has not been thoroughly evaluated experimentally. Using a direct intestinal MAP challenge model, we have observed similarities regarding persistence of MAP in tissues and apparent resilience to infection compared with experimental oral infection or natural disease. Here we sought to investigate the effects of oral monensin supplementation in experimentally MAP-infected calves. We examined the persistence of MAP in the intestinal tissues, MAP-induced intestinal inflammation, fecal MAP shedding, and seroconversion using a commercial serologic assay. Monensin-supplemented MAP-infected calves demonstrated evidence for resilience to MAP infection earlier in this study compared with monensin-free MAP-infected calves. However, statistical modeling did not identify a significant effect of monensin on outcomes of infection, and more work is required to understand how monensin affects early tissue colonization of MAP in calves.

Clinician Compliance with Laboratory Monitoring and Prescribing Guidelines in HIV-1-Infected Patients Receiving Tenofovir

BACKGROUND:Tenofovir is part of the preferred first-line regimen for HIV-infected patients in South Africa (SA); but is associated with kidney toxicity. SA antiretroviral therapy (ART) guidelines recommend creatinine monitoring at baseline (ART start) and at 3; 6 and 12 months; and substituting tenofovir with zidovudine; stavudine or abacavir should creatinine clearance (CrCl) decrease to etlt;50 mL/min. OBJECTIVE:To assess clinician compliance with tenofovir monitoring and prescribing guidelines.METHODS:We described the proportion of adult patients on tenofovir-based first-line ART who were screened for baseline renal impairment; were monitored according to the SA antiretroviral treatment guidelines; and were switched from tenofovir if renal function declined.RESULTS:We included 13 168 patients who started ART from 2010 to 2012. Creatinine concentrations were recorded in 11 712 (88.9%) patients on tenofovir at baseline; 9 135/11 657 (78.4%) at 3 months; 5 426/10 554 (51.4%) at 6 months; and 5 949/ 8 421 (70.6%) at 12 months. At baseline; 227 (1.9%) started tenofovir despite a CrCl etlt;50 mL/min. While on tenofovir; 525 patients had at least one CrCl of etlt;50 mL/min. Of 382 patients with =3 months' follow-up after a CrCl etlt;50 mL/min; 114 (29.8%) stopped tenofovir within 3 months. Clinicians were more likely to stop tenofovir in patients with lower CrCl and CD4 count. Of 226 patients who continued to receive tenofovir and had further CrCls available; 156 (69.0%) had a CrCl =50 mL/min at their next visit.CONCLUSIONS:Creatinine monitoring is feasible where access to laboratory services is good. Kidney function recovered in most patients who continued to receive tenofovir despite a CrCl etlt;50 mL/min. Further research is needed to determine how best to monitor renal function with tenofovir in resource-limited settings

Diagnostic accuracy of tuberculin skin test self-reading by HIV patients in a low-resource setting.

BACKGROUND: The World Health Organization recommends tuberculin skin tests (TSTs) where feasible to identify individuals most likely to benefit from isoniazid preventive therapy (IPT). The requirement for TST reading after 48-72 h by a trained nurse is a barrier to implementation and increases loss to follow-up. METHODS: Patients with human immunodeficiency virus (HIV) infection were recruited from a primary care clinic in South Africa and trained by a lay counsellor to interpret their own TST. The TST was placed by a nurse, and the patient was asked to return 2 days later with their self-reading result, followed by blinded reading by a trained nurse (reference). RESULTS: Of 227 patients, 210 returned for TST reading; 78% interpreted their test correctly: those interpreting it as negative were more likely to be correct (negative predictive value 93%) than those interpreting it as positive (positive predictive value 42%); 10/36 (28%) positive TST results were read as negative by the patient. CONCLUSIONS: Patients with HIV in low-resource settings can be trained to interpret their own TST. Those interpreting it as positive should return to the clinic within 48-72 h for confirmatory reading and IPT initiation; those with a negative interpretation can return at their next scheduled visit and initiate IPT at that time if appropriate.

Cognitive triggers of auditory hallucinations: an experimental investigation.

It has proved difficult to establish the internal process by which mental events are transformed into auditory hallucinations. The earlier stages of the generation of hallucinations may prove more accessible to research. Cognitions have been reported by patients as a trigger of auditory hallucinations, but the role of these preceding thoughts has not been causally determined. Therefore, the role of cognition in triggering auditory hallucinations was tested in an experimental study. Thirty individuals who experienced auditory hallucinations in social situations entered a neutral social situation presented using virtual reality. Participants randomised to the experimental condition were instructed to think their hallucination-preceding thoughts, and those randomised to the control condition were instructed to think neutral thoughts. Twenty-seven participants (93%) were able to spontaneously identify a cognition which preceded a hallucination. There was no difference between the experimental and control groups in the occurrence or severity of auditory hallucinations in virtual reality. Virtual reality did not lead to physical side effects or an increase in anxiety. The relationship between antecedent cognitions and auditory hallucinations is likely to be more complex than the one tested. It is argued that the effect of cognition on auditory hallucinations may be mediated by affect but this needs to be investigated through further experimental research.

Electronic tuberculosis surveillance systems: a tool for managing today's TB programs.

The World Health Organization (WHO) released the Stop TB Strategy in 2006, along with a revised version of the tuberculosis (TB) recording and reporting forms and register. These publications illustrate the need for an enhanced TB surveillance system that will include such key elements as rapid assessment of the quality of DOTS services; integration and response to the human immunodeficiency virus/acquired immune-deficiency syndrome (HIV/AIDS) epidemic; TB control challenges, such as increased smear-negative and extra-pulmonary TB and multidrug-resistant TB (MDR-TB); increased engagement of all care providers, such as private health care services and the community; and promotion of research to support program improvement. Electronic surveillance systems utilize computer technology to facilitate the capture, transfer and reporting of the WHO-recommended TB data elements. Electronic surveillance offers several potential advantages over the traditional paper-based systems used in many low-resource settings, such as improved data quality and completeness, more feasible links to other health care programs, quality-enhanced data entry and analysis features and increased data security. These advantages must, however, be weighed against the requirements and costs of electronic surveillance, including implementation and support of a quality paper-based surveillance system and the additional costs associated with infrastructure, training and human resources for the implementation and continuing support of an electronic system. Using examples from three different electronic TB surveillance systems that are being implemented in various resource-limited settings, this article demonstrates the feasibility, requirements and value of such systems to support the WHO-recommended enhancement of TB surveillance.

CO(2) enrichment reduces reproductive dominance in competing stands of Ambrosia artemisiifolia (common ragweed).

Plants growing in dense stands may not equally acquire or utilize extra carbon gained in elevated CO(2). As a result, reproductive differences between dominant and subordinate plants may be altered under rising CO(2) conditions. We hypothesized that elevated CO(2) would enhance the reproductive allocation of shaded, subordinate Ambrosia artemisiifolia L. (Asteraceae) individuals more than that of light-saturated dominants. We grew stands of A. artemisiifolia at either 360 or 720 muL L(-1) CO(2) levels and measured the growth and reproductive responses of competing individuals. To test whether elevated CO(2) altered size and reproductive inequalities within stands, we compared stand-level coefficients of variation (CV) in height growth and final shoot, root, and reproductive organ biomasses. Elevated CO(2) enhanced biomass and reduced the CV for all aspects of plant growth, especially reproductive biomass. Allocation to reproduction was higher in the elevated CO(2) than in the ambient treatment, and this difference was more pronounced in small, rather than large plant positive relationships between the CV and total stand productivity declined under elevated CO(2), indicating that growth enhancements to smaller plants diminished the relative biomass advantages of larger plants in increasingly crowded conditions. We conclude that elevated CO(2) stimulates stand-level reproduction while CO(2)-induced growth gains of subordinate A. artemisiifolia plants minimize differences in the reproductive output of small and large plants. Thus, more individuals are likely to produce greater amounts of seeds and pollen in future populations of this allergenic weed.

Impact of units on rotation at the National Training Center: the Fort Irwin MEDDAC experience.

Soldiers who experience orthopedic injuries during their training cycle at the National Training Center have a major impact on the Fort Irwin MEDDAC. The majority of hospital referrals from the field medical companies and admissions occur during the training days 7 through 20. Vehicular and other training accidents result in a mini-MASCAL at least once during the rotation, requiring the activation of selected MEDDAC personnel.

National Guard training: Fort Irwin MEDDAC experience during Operation Desert Storm.

The expansion of the USA MEDDAC, Fort Irwin, California, during Operation Desert Storm is described. During Operation Desert Storm, Fort Irwin and the National Training Center was responsible for training the 48th Separate Infantry Brigade National Guard from Georgia. The impact of this training upon the MEDDAC is described.