Structural and Functional Characterization of Acetoacetate Decarboxylase-Like Enzymes

The acetatoacetate decarboxylase-like superfamily (ADCSF) is a largely unexplored group of enzymes that may be a potential source of new biocatalysts. Bioinformatic analysis has grouped these approximately 2000 enzymes into seven different families based on comparison of predicted active site residues. To date, only the prototypical ADCs (Family I) that catalyze the decarboxylation of acetoacetate have been studied. Analysis of gene context suggests that Family V contains predominantly enzymes predicted to be involved in secondary metabolism. On average, these share about 20% sequence identity to the true ADCs. To learn more about the diversity of chemistries performed by members of Family V, we have been studying two enzymes annotated as acetoacetate decarboxylase in the GenBank database. These are Sbi_00515 from Streptomyces bingchenggensis and Swit_4259 from Sphingomonas wittichii. Steady state analyses of these enzymes demonstrate that both lack decarboxylase activity with any of the substrates tested. This was surprising given that the crystal structures of both enzymes show that their overall folds are almost indistinguishable from that of the prototypical ADCs, though the quaternary structures are different. An important observation from the bioinformatic and crystallographic analyses is that the catalytic lysine and putative acid/base catalyst residues of the true ADCs are retained in both groups of enzymes, but the active site architectures are different. Specifically, two residues shown to be important for the acetoacetate decarboxylase reaction, Arg29 and Glu61 in Clostridium acetobutylicum ADC (CaADC), are not retained in the Family V enzymes. Site-directed mutagenesis, steady state and transient kinetics, and mass spectroscopy data suggest evidence for reversible aldolase-dehydratase and retro-aldolase activities mediated through a Schiff-base mechanism. These are the first Schiff-base-forming aldolases that do not use the TIM barrel fold. Although the physiologically relevant reactions of these Family V enzymes are unknown, these studies illustrate that the ADC fold is a versatile platform that can be adapted to perform different chemistries

Human Rights and Professions Museums as Interlocutors of Buraku Identity in Japan

Members of the Buraku minority group in contemporary Japan are traditionally perceived as descendants of outcaste communities who performed work deemed impure according to Shinto and Buddhist taboos in Japan’s caste system during the Tokugawa Era (1603-1867). After receiving emancipation in 1871, they continued to experience severe discrimination. Following successful activism culminating in government-issued affirmative action “special measures” funding beginning in 1969, Buraku people have now approached social and economic parity with mainstream Japanese. Partially due to these successes, the Buraku Liberation League, the largest Buraku rights organization in the country, has now embraced a new globalized, UN-centric Buraku identity that situates the Buraku equality movement amongst those of other caste-based minorities. During the special measures programs of the 1990s, many Buraku communities established human rights and/or professions museums to educate the populace on Buraku discrimination while performing a reclaimed Buraku identity centering on pride in the role of Buraku professions in Japanese state-building. This project examines how Buraku identity is currently performed in those museums in light of the evolving globalized Buraku collective memory. A qualitative content analysis was performed on the websites, handouts, and publications of five different museums in various regions of Japan. Data were triangulated through fieldwork and interviews. Three main themes emerged from this analysis. First, all five museums were strongly rooted in their local communities but engaged with these communities using different mechanisms. Second, while two museums demonstrated evidence of embracing the global turn in the Buraku movement, three museums appeared to reject it. Finally, while all of the museums discuss discrimination as a salient aspect of Buraku identity, the museums in western Japan locate the root of the discrimination as stigmatized space while those in Tokyo identify pollution ideology associated with traditional Buraku professions as the source of the discrimination. This study assists in elucidating for museums some of the challenges inherent in constructing a cohesive narrative within a social minority group with an uncertain and contested master narrative. In addition, this dissertation adds to research methodology literature by synthesizing the qualitative content analysis literature and creating stepwise instructions for its use

Brainstem atrophy in focal epilepsy destabilizes brainstem-brain interactions: Preliminary findings.

BACKGROUND: MR Imaging has shown atrophy in brainstem regions that were linked to autonomic dysfunction in epilepsy patients. The brainstem projects to and modulates the activation state of several wide-spread cortical/subcortical regions. The goal was to investigate 1. Impact of brainstem atrophy on gray matter connectivity of cortical/subcortical structures and autonomic control. 2. Impact on the modulation of cortical/subcortical functional connectivity. METHODS: 11 controls and 18 patients with non-lesional focal epilepsy (FE) underwent heart rate variability (HRV) measurements and a 3 T MRI (T1 in all subjects, task-free fMRI in 7 controls/ 12 FE). The brainstem was extracted, and atrophy assessed using deformation-based-morphometry. The age-corrected z-scores of the mean Jacobian determinants were extracted from 71 5x5x5 mm grids placed in brainstem regions associated with autonomic function. Cortical and non-brainstem subcortical gray matter atrophy was assessed with voxel-based-morphometry and mean age corrected z-scores of the modulated gray matter volumes extracted from 380 cortical/subcortical rois. The profile similarity index was used to characterize the impact of brainstem atrophy on gray matter connectivity. The fMRI was preprocessed in SPM12/Conn17 and the BOLD signal extracted from 398 ROIs (16 brainstem). A dynamic task-free analysis approach was used to identify activation states. Connectivity HRV relationship were assessed with Spearman rank correlations. RESULTS: HRV was negatively correlated with reduced brainstem right hippocampus/parahippocampus gray matter connectivity in controls (p \u3c .05, FDR) and reduced brainstem to right parietal cortex, lingual gyrus, left hippocampus/amygdala, parahippocampus, temporal pole, and bilateral anterior thalamus connectivity in FE (p \u3c .05, FDR). Dynamic task-free fMRI analysis identified 22 states. The strength of the functional brainstem/cortical connectivity of state 15 was negatively associated with HRV (r = -0.5, p = .03) and positively with decreased brainstem-cortical (0.49, p = .03) gray matter connectivity. CONCLUSION: The findings of this small pilot study suggest that impaired brainstem-cortex gray matter connectivity in FE negatively affects the brainstem\u27s ability to control cortical activation

Frequency-Unspecific Effects of θ-tACS Related to a Visuospatial Working Memory Task

Working memory (WM) is crucial for intelligent cognitive functioning, and synchronization phenomena in the fronto-parietal network have been suggested as an underlying neural mechanism. In an attempt to provide causal evidence for this assumption, we applied transcranial alternating current stimulation (tACS) at theta frequency over fronto-parietal sites during a visuospatial match-to-sample (MtS) task. Depending on the stimulation protocol, i.e., in- phase, anti-phase or sham, we anticipated a differential impact of tACS on behavioral WM performance as well as on the EEG (electroencephalography) during resting state before and after stimulation. We hypothesized that in- phase tACS of the fronto-parietal theta network (stimulation frequency: 5 Hz; intensity: 1 mA peak-to-peak) would result in performance enhancement, whereas anti-phase tACS would cause performance impairment. Eighteen participants (nine female) received in-phase, anti-phase, and sham stimulation in balanced order. While being stimulated, subjects performed the MtS task, which varied in executive demand (two levels: low and high). EEG analysis of power peaks within the delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–12 Hz), and beta (12–30 Hz) frequency bands was carried out. No significant differences were observed between in-phase and anti-phase stimulation regarding both behavioral and EEG measurements. Yet, with regard to the alpha frequency band, we observed a statistically significant drop of peak power from pre to post in the sham condition, whereas alpha power remained on a similar level in the actively stimulated conditions. Our results indicate a frequency-unspecific modulation of neuronal oscillations by tACS. However, the closer participants’ individual theta peak frequencies were to the stimulation frequency of 5 Hz after anti- phase tACS, the faster they responded in the MtS task. This effect did not reach statistical significance during in-phase tACS and was not present during sham. A lack of statistically significant behavioral results in the MtS task and frequency-unspecific effects on the electrophysiological level question the effectiveness of tACS in modulating cortical oscillations in a frequency- specific manner

Cutaneous Ewing Sarcoma and Ewing Sarcoma of the Bone: Distinct Diseases

Ewing sarcoma is an aggressive mesenchymal malignancy. It is the second most common bone tumor among children and adolescents and less commonly presents as a soft tissue or primary skin lesion. Cutaneous Ewing sarcoma has only been reported in case reports and case series. In this article, we describe a 12-year-old Hispanic female cured of localized, cutaneous Ewing sarcoma (pT1aN0M0) at the 40-month follow-up following surgical resection and adjuvant chemotherapy according to the COG AEWS1031 protocol for Ewing sarcoma of the bone. To our knowledge, this is the first article to provide a potential biological explanation for the differences in the prognosis of Ewing sarcoma of the bone, soft tissue, and skin

Report on the health of Colorado's forests

The reports describes "an annual investigation of critical forest health issues, including the identification of priority areas across the state where current forest conditions demand timely action." They are intended to "expand Coloradans' knowledge of and interest in our state's forest resources.".Reports produced by the Colorado State Forest Service in conjunction with Colorado Department of Natural Resources, Division of Forestry.Includes bibliographical references.January 2017Fire and water. The words themselves evoke contrasting forces of nature - fire, often viewed as an all-consuming inferno of destruction; water, a quenching and life-sustaining means of rejuvenation. But such generalizations are not always accurate, especially in Colorado. Fire is necessary to the ecology of healthy forests, and can be a useful wildland firefighting tool for containment and fuels reduction, while life-giving streams and rivers may turn into raging torrents that cause heavy erosion and loss of property and life. So important are these two natural elements that we've chosen them for the focus of this year's forest health report, to give you a better understanding of their impacts on Colorado's forested lands. Fire and water are integrally linked as necessary components in shaping a healthy, natural forest environment; in return, both are heavily influenced by forests themselves. Fire has significant impacts on people and forests; less obvious are the effects it has on the quality and quantity of water available for human and agricultural consumption. The demand for water, of particular concern in rapidly developing sections of our state, underscores the need to work across organizational boundaries to develop effective solutions. Interagency efforts highlight the importance of forest management to safeguard water supplies from post-fire erosion so water providers can maintain their ability to provide safe, clean water to Colorado residents in a cost-effective, consistent manner. In this report, we take the opportunity to highlight collaborative partnerships and projects with Denver Water, Northern Water, the City of Ouray and professionals implementing Colorado's Water Plan