Combining the effects of increased atmospheric carbon dioxide on protein, iron, and zinc availability and projected climate change on global diets: a modelling study.

BACKGROUND: Increasing atmospheric concentrations of carbon dioxide (CO2) affect global nutrition via effects on agricultural productivity and nutrient content of food crops. We combined these effects with economic projections to estimate net changes in nutrient availability between 2010 and 2050. METHODS: In this modelling study, we used the International Model for Policy Analysis of Agricultural Commodities and Trade to project per capita availability of protein, iron, and zinc in 2050. We used estimated changes in productivity of individual agricultural commodities to model effects on production, trade, prices, and consumption under moderate and high greenhouse gas emission scenarios. Two independent sources of data, which used different methodologies to determine the effect of increased atmospheric CO2 on different key crops, were combined with the modelled food supply results to estimate future nutrient availability. FINDINGS: Although technological change, market responses, and the effects of CO2 fertilisation on yield are projected to increase global availability of dietary protein, iron, and zinc, these increases are moderated by negative effects of climate change affecting productivity and carbon penalties on nutrient content. The carbon nutrient penalty results in decreases in the global availability of dietary protein of 4·1%, iron of 2·8%, and zinc of 2·5% as calculated using one dataset, and decreases in global availability of dietary protein of 2·9%, iron of 3·9%, and zinc of 3·4% using the other dataset. The combined effects of projected increases in atmospheric CO2 (ie, carbon nutrient penalty, CO2 fertilisation, and climate effects on productivity) will decrease growth in the global availability of nutrients by 19·5% for protein, 14·4% for iron, and 14·6% for zinc relative to expected technology and market gains by 2050. The many countries that currently have high levels of nutrient deficiency would continue to be disproportionately affected. INTERPRETATION: This approach is an improvement in estimating future global food security by simultaneously projecting climate change effects on crop productivity and changes in nutrient content under increased concentrations of CO2, which accounts for a much larger effect on nutrient availability than CO2 fertilisation. Regardless of the scenario used to project future consumption patterns, the net effect of increasing concentrations of atmospheric CO2 will slow progress in decreasing global nutrient deficiencies. FUNDING: US Environmental Protection Agency, Consultative Group on International Agricultural Research (CIGAR) Research Program on Policies, Institutions and Markets (PIM), and the CGIAR Research Program on Climate Change and Food Security (CCAFS).

Levamisole-Adulterated Cocaine Nephrotoxicity: Ultrastructural Features.

OBJECTIVES: The issue of levamisole-adulterated cocaine is emerging as a rapidly growing public health concern due to an increasing number of reports describing its role in cutaneous vasculitis and agranulocytosis. Of note, levamisole is recognized as a contaminant in 69% of the cocaine used within the United States. METHODS: We describe a patient who was a chronic cocaine user and developed systemic vasculitis characterized by polyarthralgia, bullous skin lesions, agranulocytosis, and antineutrophil cytoplasmic antibody-positive rapidly progressive glomerulonephritis. RESULTS: The skin biopsy specimen demonstrated leukocytoclastic vasculitis. The renal biopsy specimen revealed pauci-immune necrotizing and crescentic glomerulonephritis and unusual deposits with medium electron density composed of granules, microspherules, and rare single fibrils on electron microscopy. CONCLUSIONS: The electron microscopic features of levamisole-adulterated cocaine toxicity are novel findings that are presented for the first time, to our knowledge, in this report.

Visual field defects after radiosurgery for mesial temporal lobe epilepsy.

PURPOSE: Gamma knife radiosurgery (RS) may be an alternative to open surgery for mesial temporal lobe epilepsy (MTLE), but morbidities and the anticonvulsant mechanisms of RS are unclear. Examination of visual field defects (VFDs) after RS may provide evidence of the extent of a postoperative fixed lesion. VFDs occur in 52-100% of patients following open surgery for MTLE. METHODS: This multicenter prospective trial of RS enrolled patients with unilateral hippocampal sclerosis and concordant video-electroencephalography (EEG) findings. Patients were randomized to low (20 Gy) or high (24 Gy) doses delivered to the amygdala, hippocampal head, and parahippocampal gyrus. Postoperative perimetry were obtained at 24 months after RS. Visual field defect ratios (VFDRs) were calculated to quantify the degree of VFDs. Results were contrasted with age, RS dose and 50% isodose volume, peak volume of radiation-induced change at the surgical target, quality of life measurements, and seizure remission. KEY FINDINGS: No patients reported visual changes and no patients had abnormal bedside visual field examinations. Fifteen (62.5%) of 24 patients had postoperative VFDs, all homonymous superior quadrantanopsias. None of the VFDs were consistent with injury to the optic nerve or chiasm. Clinical diagnosis of VFDs correlated significantly with VFDRs (p = 0.0005). Patients with seizure remission had smaller (more severe) VFDRs (p = 0.04). No other variables had significant correlations. SIGNIFICANCE: VFDs appeared after RS in proportions similar to historical comparisons from open surgery for MTLE. The nature of VFDs was consistent with lesions of the optic radiations. The findings support the hypothesis that the mechanism of RS involves some degree of tissue damage and is not confined entirely to functional changes in neuromodulation.

North Carolina tobacco farmers' changing perceptions of tobacco control and tobacco manufacturers.

PURPOSE: To examine tobacco farmers' attitudes toward tobacco control, public health, and tobacco manufacturers in order to determine the extent to which rapidly changing economic conditions have influenced North Carolina tobacco farmer attitudes in ways that may provide tobacco control advocates with new opportunities to promote tobacco control policies in tobacco-dependent US communities. METHODS: We used data from a longitudinal sample of North Carolina tobacco farmers across 5 waves of data collection (1997-2005) (baseline N = 749 farmers). Generalized linear mixed models were used to examine changes in attitudes toward tobacco control and tobacco manufacturers, controlling for economic dependence on tobacco, and demographic factors. RESULTS: Over the study period there was reduction in tobacco farmers' perceptions of threat from tobacco control initiatives. CONCLUSIONS: These changes in attitude may signal an opportunity for successful tobacco control activity in traditionally tobacco-dependent states and rural communities.

A multicenter, prospective pilot study of gamma knife radiosurgery for mesial temporal lobe epilepsy: seizure response, adverse events, and verbal memory.

OBJECTIVE: The safety, efficacy, and morbidity of radiosurgery (RS) must be established before it can be offered as an alternative to open surgery for unilateral mesial temporal lobe epilepsy. We report the 3-year outcomes of a multicenter, prospective pilot study of RS. METHODS: RS was randomized to 20 or 24Gy targeting the amygdala, hippocampus, and parahippocampal gyrus. Seizure diaries evaluated the final seizure remission between months 24 and 36. Verbal memory was evaluated at baseline and 24m with the Wechsler Memory Scale-Revised (WMS-R) and California Verbal Learning Test (CVLT). Patients were classified as having "significant improvement," "no change," and "significant impairment" based on relative change indices. RESULTS: Thirteen high-dose and 17 low-dose patients were treated. Both groups showed significant reductions in seizures by 1 year after treatment. At the 36-month follow-up evaluation, 67% of patients were free of seizures for the prior 12 months (high dose: 10/13, 76.9%; low dose: 10/17, 58.8%). Use of steroids, headaches, and visual field defects did not differ by dose or seizure remission. The prevalence of verbal memory impairment was 15% (4/26 patients); none declined on more than one measure. The prevalence of significant verbal memory improvements was 12% (3/26). INTERPRETATION: RS for unilateral mesial temporal lobe epilepsy offers seizure remission rates comparable with those reported previously for open surgery. There were no major safety concerns with high-dose RS compared with low-dose RS. Additional research is required to determine whether RS may be a treatment option for some patients with mesial temporal lobe epilepsy.

Tobacco farmers and tobacco manufacturers: implications for tobacco control in tobacco-growing developing countries.

Assisting tobacco farmers to transition to non-tobacco alternatives is a key element of comprehensive tobacco control's end-game strategy and specifically required by the World Health Organization (WHO) Framework Convention for Tobacco Control (FCTC). We examine the historical relationship between tobacco manufacturers and tobacco farmers in the United States, where the duration of the relationship has been longest and use information obtained to inform possible end-game strategies for tobacco control advocates working with tobacco farmers in developing countries. Tobacco Documents obtained under the Master Settlement Agreement (MSA) provide evidence of conflicts between tobacco manufacturers and tobacco farmers. Findings support WHO FCTC articles aimed at helping developing country tobacco farmers adversely affected by tobacco control efforts and highlight difficulties in discouraging tobacco cultivation as long as it remains relatively profitable. We conclude that successful end-game strategies should take a long-term approach aimed at building alliances with tobacco farmers and at creating mechanisms for tobacco farmer investment in local infrastructure.

Avoided deforestation as a greenhouse gas mitigation tool: economic issues.

Tropical deforestation is a significant contributor to accumulation of greenhouse gases (GHGs) in the atmosphere. GHG emissions from deforestation in the tropics were in the range of 1 to 2 Pg C yr(-1) for the 1990s, which is equivalent to as much as 25% of global anthropogenic GHG emissions. While there is growing interest in providing incentives to avoid deforestation and consequently reduce net carbon emissions, there is limited information available on the potential costs of these activities. This paper uses a global forestry and land use model to analyze the potential marginal costs of reducing net carbon emissions by avoiding deforestation in tropical countries. Our estimates suggest that about 0.1 Pg C yr(-1) of emissions reductions could be obtained over the next 30 to 50 yr for $5 per Mg C, and about 1.6 Pg C yr(-1) could be obtained over the same time frame for $100 per Mg C. In addition, the effects of carbon incentives on land use could be substantial. Relative to projected baseline conditions, we find that there would be around 3 million additional hectares (ha) of forestland in 2055 at $5 per Mg C and 422 million ha at $100 per Mg C. Estimates of reductions in area deforested, GHG mitigation potential, and annual land rental payments required are presented, all of which vary by region, carbon price paid, and time frame of mitigation.

Funding of North Carolina tobacco control programs through the Master Settlement Agreement.

Changing political and economic forces in 1 tobacco-dependent state, North Carolina, demonstrate how the interplay between these forces and public health priorities has shaped current allocation of Master Settlement Agreement funds. Allocation patterns demonstrate lawmakers' changing priorities in response to changes in the economic climate; some of the agreement's funds targeted to tobacco farmers appear to reflect objectives favored by tobacco manufacturers. Funds earmarked for health have underfunded youth tobacco prevention and tobacco control initiatives, and spending for tobacco farmers in North Carolina has not lived up to the rhetoric that accompanied the original agreement. We discuss the implications of these findings for future partnerships between public health advocates and workers as well as tobacco control strategies.