A Study of the Structure and Metabolic Processes of a Novel Membrane Cytochrome in an Extreme Microbial Community

The action of iron oxidizing microbes can generate acid mine drainage (AMD), characterized by acidic, toxic metal-tainted water that pollutes various water resources. The acidophilic biofilm community populating the Richmond mine, a pyrite (FeS{sub 2}) deposit in Northern California, is a key component of the oxidation of Fe(II) as well as subsequent pyrite dissolution. These natural biofilms contain many novel proteins that are being studied in order to understand how these microbes oxidize iron. The focus of this study is on the structure and characteristics of one novel, abundant outer membrane protein, cytochrome 572 (Cyt{sub 572}), which is perhaps important to the function of the entire community. To detect and study this cytochrome, monoclonal antibodies (mAb) were produced and screened for specificity to Cyt{sub 572}, both purified and membrane-bound. This was accomplished using enzyme linked immunosorbent assay (ELISA) and western blot analysis. Using western blotting, the presence of three high molecular weight bands at positions of dimer, trimer and tetramer corroborate chromatographic results that Cyt{sub 572} is a tetramer. Immunoprecipitation was used to detect a Cyt{sub 572} specific multiprotein complex, and these experiments are in progress. Apart from its novel amino acid sequence, Cyt{sub 572} binds to a heme group that exhibits unique spectral properties. To characterize the heme further, several biochemical methods were used to examine the purified cytochrome. Ethidium bromide was used in a novel way to detect proteins containing heme. The smallest heme-binding polypeptide fragment, about 23kDa, was identified by gel electrophoresis after proteolytic digestion of purified Cyt{sub 572}. The inability of these enzyme digests to completely degrade the protein reveals a secondary structure protective mechanism surrounding the heme group. This is perhaps associated with biofilm membrane proteins like Cyt{sub 572} that are in contact with an extremely acidic environment. Heme-protein interactions and higher order protein complexes have likely been selected for stability and the efficient transfer of electrons from Fe(II) to cells for energy, an essential function in the biofilm community

Clark County Department of Family Services, Parenting Project

The Clark County Parenting Project offers a series of free programs to help parents become more effective in raising their children. This program evaluation focuses on Teen Triple P, one of the six programs offered by Clark County, evaluating the effectiveness of the program to the community. The Parenting Project partnered with the University of Nevada, Las Vegas, School of Public Policy and Leadership to be a participant in a program evaluation. The evaluation will serve as a tool to determine the overall effectiveness in meeting program goals and objectives as well as determining strengths and weaknesses in program implementation

Reverted exhaustion phenotype of circulating lymphocytes as immune correlate of anti-PD1 first-line treatment in Hodgkin lymphoma

While classical Hodgkin lymphoma (HL) is highly susceptible to anti-programmed death protein 1 (PD1) antibodies, the exact modes of action remain controversial. To elucidate the circulating lymphocyte phenotype and systemic effects during anti-PD1 1st-line HL treatment we applied multicolor flow cytometry, FluoroSpot and NanoString to sequential samples of 81 HL patients from the NIVAHL trial (NCT03004833) compared to healthy controls. HL patients showed a decreased CD4 T-cell fraction, a higher percentage of effector-memory T cells and higher expression of activation markers at baseline. Strikingly, and in contrast to solid cancers, expression for 10 out of 16 analyzed co-inhibitory molecules on T cells (e.g., PD1, LAG3, Tim3) was higher in HL. Overall, we observed a sustained decrease of the exhausted T-cell phenotype during anti-PD1 treatment. FluoroSpot of 42.3% of patients revealed T-cell responses against ≥1 of five analyzed tumor-associated antigens. Importantly, these responses were more frequently observed in samples from patients with early excellent response to anti-PD1 therapy. In summary, an initially exhausted lymphocyte phenotype rapidly reverted during anti-PD1 1st-line treatment. The frequently observed IFN-y responses against shared tumor-associated antigens indicate T-cell-mediated cytotoxicity and could represent an important resource for immune monitoring and cellular therapy of HL

A Kalman Filter Approach for Estimating Tendon Wave Speed from Skin-Mounted Accelerometers

Shear wave tensiometry is a noninvasive approach for assessing in vivo tendon forces based on the speed of a propagating shear wave. Wave speed is measured by impulsively exciting a shear wave in a tendon and then assessing the wave travel time between skin-mounted accelerometers. Signal distortion with wave travel can cause errors in the estimated wave travel time. In this study, we investigated the use of a Kalman filter to fuse spatial and temporal accelerometer measurements of wave propagation. Spatial measurements consist of estimated wave travel times between accelerometers. Temporal measurements are the change in wave arrival at a fixed accelerometer between successive impulsive taps. The Kalman filter substantially improved the accuracy of estimated wave speeds when applied to simulated tensiometer data. The variability of estimated wave speed was reduced by ~55% in the presence of random sensor noise. It was found that increasing the number of accelerometers from two to three further reduced wave speed errors by 45%. The use of redundant accelerometers (>2) also improved the robustness of wave speed measures in the presence of uncertainty in accelerometer location. We conclude that the use of a Kalman filter and redundant accelerometers can enhance the fidelity of using shear wave tensiometers to track tendon wave speed and loading during movement

Limited short-term prognostic utility of cerebral NIRS during neonatal therapeutic hypothermia

Objective: We evaluated the utility of amplitude-integrated EEG (aEEG) and regional oxygen saturation (rSO2) measured using near-infrared spectroscopy (NIRS) for short-term outcome prediction in neonates with hypoxic ischemic encephalopathy (HIE) treated with therapeutic hypothermia. Methods: Neonates with HIE were monitored with dual-channel aEEG, bilateral cerebral NIRS, and systemic NIRS throughout cooling and rewarming. The short-term outcome measure was a composite of neurologic examination and brain MRI scores at 7 to 10 days. Multiple regression models were developed to assess NIRS and aEEG recorded during the 6 hours before rewarming and the 6-hour rewarming period as predictors of short-term outcome. Results: Twenty-one infants, mean gestational age 38.8 ± 1.6 weeks, median 10-minute Apgar score 4 (range 0–8), and mean initial pH 6.92 ± 0.19, were enrolled. Before rewarming, the most parsimonious model included 4 parameters (adjusted R2 = 0.59; p = 0.006): lower values of systemic rSO2 variability (p = 0.004), aEEG bandwidth variability (p = 0.019), and mean aEEG upper margin (p = 0.006), combined with higher mean aEEG bandwidth (worse discontinuity; p = 0.013), predicted worse short-term outcome. During rewarming, lower systemic rSO2variability (p = 0.007) and depressed aEEG lower margin (p = 0.034) were associated with worse outcome (model-adjusted R2 = 0.49; p = 0.005). Cerebral NIRS data did not contribute to either model. Conclusions: During day 3 of cooling and during rewarming, loss of physiologic variability (by systemic NIRS) and invariant, discontinuous aEEG patterns predict poor short-term outcome in neonates with HIE. These parameters, but not cerebral NIRS, may be useful to identify infants suitable for studies of adjuvant neuroprotective therapies or modification of the duration of cooling and/or rewarming