Toward the improvement of total nitrogen deposition budgets in the United States

Frameworks for limiting ecosystem exposure to excess nutrients and acidity require accurate and complete deposition budgets of reactive nitrogen (Nr). While much progress has been made in developing total Nr deposition budgets for the U.S., current budgets remain limited by key data and knowledge gaps. Analysis of National Atmospheric Deposition Program Total Deposition (NADP/TDep) data illustrates several aspects of current Nr deposition that motivate additional research. Averaged across the continental U.S., dry deposition contributes slightly more (55%) to total deposition than wet deposition and is the dominant process (>90%) over broad areas of the Southwest and other arid regions of the West. Lack of dry deposition measurements imposes a reliance on models, resulting in a much higher degree of uncertainty relative to wet deposition which is routinely measured. As nitrogen oxide (NOx) emissions continue to decline, reduced forms of inorganic nitrogen (NHx = NH3 + NH4+) now contribute >50% of total Nr deposition over large areas of the U.S. Expanded monitoring and additional process-level research are needed to better understand NHx deposition, its contribution to total Nr deposition budgets, and the processes by which reduced N deposits to ecosystems. Urban and suburban areas are hotspots where routine monitoring of oxidized and reduced Nr deposition is needed. Finally, deposition budgets have incomplete information about the speciation of atmospheric nitrogen; monitoring networks do not capture important forms of Nr such as organic nitrogen. Building on these themes, we detail the state of the science of Nr deposition budgets in the U.S. and highlight research priorities to improve deposition budgets in terms of monitoring and flux measurements, leaf- to regional-scale modeling, source apportionment, and characterization of deposition trends and patterns.

Exploring a United States Maize Cellulose Biofuel Scenario Using an Integrated Energy and Agricultural Markets Solution Approach

Biofuel feedstock production in the United States (US) is an emergent environmental nutrient management issue, whose exploration can benefit from a multi-scale and multimedia systems modeling approach that explicitly addresses diverging stakeholder interests. In the present analysis, energy and agricultural markets models and a hybrid process-based agricultural production model are integrated to explore the potential environmental consequences of increased biofuel production from maize grain and stover feedstocks. Yield and cropland reallocation projections are simulated for 20 agricultural crops at a 12km grid resolution across the continental United States. Our results are presented across multiple, spatially expanding domains, and our results for the Upper Mississippi River Basin (UMRB) are compared to previous studies. Our analysis highlights the critical continuing role of agricultural and crop science to provide physically plausible estimates and physical process drivers of yield increases, and suggests that while the UMRB is the target of the greatest agricultural changes under our scenarios, its response does not necessarily reflect the interests of a broad stakeholder community.

Results of complete soft tissue clubfoot release combined with calcaneocuboid fusion in the 4-year to 8-year age group following failed clubfoot release

A subset of postoperative recurrent clubfeet was isolated in a group of patients 4 to 8 years old. Twenty-seven consecutive patients who underwent redo surgery consisting of complete soft tissue clubfoot release combined with a calcaneocuboid fusion were reviewed for this study. Twenty-six feet of 27 feet in 20 patients had a long-term good result, suggesting that this procedure is the one of choice for this age group.

Rel/NF-kappaB can trigger the Notch signaling pathway by inducing the expression of Jagged1, a ligand for Notch receptors

Jagged1 belongs to the DSL family of ligands for Notch receptors that control the proliferation and differentiation of various cell lineages. However, little is known about the transcription factors that regulate its expression. Here, we show that Jagged1 is a Rel/NF-kappaB-responsive gene. Both c-Rel and RelA induced jagged1 gene expression, whereas a mutant defective for transactivation did not. Importantly, jagged1 transcripts were also upregulated by endogenous NF-kappaB activation and this effect was inhibited by a dominant mutant of IkappaBalpha, a physiological inhibitor of NF-kappaB. Cell surface expression of Jagged1 in c-Rel-expressing cell monolayers led to a functional interaction with lymphocytes expressing the Notch1/TAN-1 receptor. This correlated with the initiation of signaling downstream of Notch, as evidenced by increased levels of HES-1 transcripts in co-cultivated T cells and of CD23 transcripts in co-cultivated B cells. Consistent with its Rel/NF-kappaB-dependent induction, Jagged1 was found to be highly expressed in splenic B cells where c-Rel is expressed constitutively. These results demonstrate that c-Rel can trigger the Notch signaling pathway in neighboring cells by inducing jagged1 gene expression, and suggest a role for Jagged1 in B-cell activation, differentiation or function. These findings also highlight the potential for an interplay between the Notch and NF-kappaB signaling pathways in the immune system.

The prosurvival Bcl-2 homolog Bfl-1/A1 is a direct transcriptional target of NF-kappaB that blocks TNFalpha-induced apoptosis

Bcl-2-family proteins are key regulators of the apoptotic response. Here, we demonstrate that the pro-survival Bcl-2 homolog Bfl-1/A1 is a direct transcriptional target of NF-kappaB. We show that bfl-1 gene expression is dependent on NF-kappaB activity and that it can substitute for NF-kappaB to suppress TNFalpha-induced apoptosis. bfl-1 promoter analysis identified an NF-kappaB site responsible for its Rel/NF-kappaB-dependent induction. The expression of bfl-1 in immune tissues supports the protective role of NF-kappaB in the immune system. The activation of Bfl-1 may be the means by which NF-kappaB functions in oncogenesis and promotes cell resistance to anti-cancer therapy.

Rel blocks both anti-Fas- and TNF alpha-induced apoptosis and an intact Rel transactivation domain is essential for this effect

The v-Rel oncoprotein must be continuously expressed to prevent the apoptosis of transformed lymphoid cells, and also inhibits TNF alpha-induced cell death. A tetracycline-regulated cell system was used to characterize the functions necessary for the anti-apoptotic activity of Rel proteins. v-Rel mutants defective for DNA binding or transactivation showed no protective effect. Similarly, whereas the transcription-competent c-Rel and RelA proteins inhibited TNF alpha-induced cytolysis, the transactivation-negative p50/NF-kappa B1 did not. Importantly, this study is the first to show that c-Rel can also confer significant protection from Fas-mediated cell death. Since the TNFR1- and Fas-signaling pathways involve some intermediates that are common and others that are unique to each pathway, these findings indicate that c-Rel may regulate the expression of genes that function to antagonize either or both death-signaling pathways.

c-Rel arrests the proliferation of HeLa cells and affects critical regulators of the G1/S-phase transition

A tetracycline-regulated system was used to characterize the effects of c-Rel on cell proliferation. The expression of c-Rel in HeLa cells led to growth arrest at the G1/S-phase transition, which correlated with its nuclear localization and the induction of endogenous IkappaB alpha expression. These changes were accompanied by a decrease in E2F DNA binding and the accumulation of the hypophosphorylated form of Rb. In vitro kinase assays showed a reduction in Cdk2 kinase activity that correlated with elevated levels of p21WAF1 Cdk inhibitor and p53 tumor suppressor protein. While the steady-state levels of WAF1 transcripts were increased, pulse-chase analysis revealed a sharp increase in p53 protein stability. Importantly, the deletion of the C-terminal transactivation domains of c-Rel abolished these effects. Together, these studies demonstrate that c-Rel can affect cell cycle control and suggest the involvement of the p21WAF1 and p53 cell cycle regulators.

v-Rel prevents apoptosis in transformed lymphoid cells and blocks TNFalpha-induced cell death

The v-Rel oncoprotein belongs to the Rel/NF-kappaB family of transcription factors. It transforms chicken lymphoid cells in vitro and induces fatal lymphomas in vivo. In this study, we used a tetracycline-regulated system to characterize the role of v-Rel in cell transformation. We show that the continued expression of v-Rel is necessary to maintain the viability of transformed lymphoid cells and enables primary spleen cells to escape apoptosis in vitro culture. In agreement with a possible role for v-Rel in the inhibition of programmed cell death, its inducible expression in HeLa cells prevented TNFalpha-induced apoptosis. While the repression of v-Rel was accompanied by the rapid degradation of IkappaBalpha, changes in the steady-state levels of the apoptosis inhibitors Bcl-2 and Bcl-X(L) were only observed following the onset of cell death in transformed lymphoid cells. This suggests that the anti-apoptotic activity of v-Rel may affect other apoptosis inhibitors or other factors in the death pathway. Together, these findings demonstrate that v-Rel blocks apoptosis and suggest that this activity may be an important component of its transforming function.

Combined hip surgery in cerebral palsy patients

Seventeen cases of dislocated/subluxated hips in 14 cerebral palsy patients that were relocated by the combined hip procedure were reviewed. The combined hip procedure includes varus derotation osteotomy, open reduction, innominate bone osteotomy, adductor releases, and iliopsoas recession, all done at one stage. Eleven patients were spastic quadriplegic, 1 was spastic diplegic; and 2 were spastic hemiplegic. Average age at operation was 10 years. Average follow-up was 3 years. A total of 16 hips (94%) remained stable at follow-up with almost no change in center edge angle and the migration percentage, although the neck shaft angle remodeled over time. We conclude that the combined hip procedure is effective in maintaining hip reduction in cerebral palsy patients.

Diagnosis of osteoid osteoma in the child

Fifty-two cases of osteoid osteoma in children under 5 years of age were collected from the English literature and reviewed, along with seven cases from the Hospital for Joint Diseases. Analytic emphasis was placed on the clinical and radiologic difficulties encountered in the diagnosis of osteoid osteoma in children. Diagnosis is especially challenging in patients that are just beginning to walk. Osteoid osteoma is often confused with many other entities. Although pain was the most frequent clinical manifestation, it was absent in 12% of cases; limp tenderness, swelling, and atrophy were the next most frequent findings. When standard radiographic findings proved negative for this condition, technetium bone scans were of considerable efficacy in identifying the tumor. When used, computerized tomograms permitted visualization and precise localization of the tumors in all cases. Bone deformities and leg-length discrepancies were found in more than 25% of the cases. Mini-block excision is recommended at diagnosis.

Osteoid osteoma under the age of five years. The difficulty of diagnosis

Ninety-one cases of histologically confirmed osteoid osteoma were collected during an 11-year period; of them, seven (7.6%) had onset of symptoms while younger than five years of age. Special diagnostic difficulties were found in this specific age group: most cases were misdiagnosed or diagnosed incorrectly. The time between the onset of symptoms and the diagnosis varied from three months to five years. Although pain was present in six patients, in four cases, other concomitant signs and symptoms attracted more attention and led to a misdiagnosis and unnecessary invasive procedures. Gait disturbance (limp) was the second most frequent sign and was always present when the lower extremity was affected. In five cases, initial radiographs were not conclusive. Bone scans were very sensitive and conclusive in three cases where radiographs were atypical. Computerized tomograms always located the tumor.

Improvement in disease-free survival of melanoma patients in conjunction with serologic response in a phase Ia/Ib Southeastern Cancer Study Group trial of vaccinia melanoma oncolysate

Thirty-nine patients with malignant melanoma who were disease-free after surgery but at high risk for recurrence were treated with vaccinia melanoma oncolysate (VMO) for 12 months. Clinical results, after a mean follow-up of 17 months showed that 25 of 39 patients had no evidence of disease. Comparison of disease-free survival of patients in this study with that of 39 matched controls from other adjuvant trials shows statistically significant advantage of VMO therapy. Evaluation of serological responses of patients undergoing VMO treatment by an enzyme-linked immunosorbant assay (ELISA) showed a positive correlation between IgG antibody binding to cultured melanoma cells and disease-free survival.

A phase I/II SECSG (Southeastern Cancer Study Group) pilot study of surgical adjuvant immunotherapy with vaccinia melanoma oncolysates (VMO)

Forty-eight patients with nonrecurrent high risk Stage I and II malignant melanoma were treated with Vaccinia Melanoma Oncolysates (VMO). Six different dose levels and two different treatment regimens were tested. Thirty-two out of 48 patients completed the 12 months of therapy. Side effects were mild to moderate. Twenty-eight out of 48 patients remain free from disease with a mean survival of 19 months, while 20/48 patients have recurred with a mean time to recurrence of 6 months.