Soluble cytochrome b5 reductase from human erythrocytes

1. An enzyme that catalyzes the reduction of erythrocyte cytochrome b5 has been isolated from the supernatant fraction of erythrocyte hemolysates by chromatography on DEAE-cellulose, Amberlite CG-50, and Bio-Gel P-60.2. Erythrocyte cytochrome b5 reductase has been shown to contain FAD. Incubation of the reductase in the absence of EDTA results in both the appearance of flavin fluorescence and the loss of enzymatic activity with time.3. The reductase catalyzes the reduction of erythrocyte cytochrome b5 50 times faster with NADH than with NADPH. The apparent Km of NADH was calculated to be 1.6 x 10-6 M and the turnover number is 1280 moles of cytochrome b5 per min per mole of flavin. The reduction of electron acceptors proceeded in the following decreasing order of rate: K3Fe(CN)6, 2,6-dichlorophenolindophenol (DCIP), cytochrome b5, methylene blue, cytochrome c, O2, oxidized glutathione, and methemoglobin.4. The FAD prosthetic group, the substrate specificity, and the effect of ionic strength, pH, and EDTA on activity suggest that the reductase is the same enzyme as NADH dehydrogenase I, the enzyme lacking in many cases of congenital methemoglobinemia. The properties of the reductase, including its molecular weight, are very similar to those of the cytochrome b5 reductases solubilized from microsomes and mitochondria of other tissues.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34070/1/0000348.pd

A New Dataset Integrating Public Socioeconomic, Physical Risk, and Housing Data for Climate Justice Metrics: A Test-Case Study in Miami

Assessing the impact of climate change on vulnerable populations and the implications of such impacts is a critical step toward climate and environmental justice. In general, indices or metrics that aim at studying linkages between climatic environmental impacts and vulnerable populations lack housing information. Financially relevant real estate data (e.g., mortgages, evictions) alongside other socioeconomic and physical risk information can, however, provide a crucial lens to assess climate justice. In addition, standard socioeconomic and demographic variables aggregated at census units lack the granularity required to capture inequalities, especially in heterogeneous communities, so there is a need for publicly available, ready-to-use, digitized, and distributed datasets containing relevant inequality metrics using real estate and financial information. Also, studies focusing on damages and financial impacts of climate change often use commercial datasets, which must be acquired for hundreds of thousands of dollars, making the inclusion of such information prohibitive for advocacy groups, journalists, and other interested people. With this in mind, we integrated multiple publicly available datasets that include socioeconomic, climate risk scores, evictions, and housing variables at the census tract level over the United States to be used to investigate environmental justice themes. Our goal is that the dataset proposed here will allow for testing, assessing, and generating new analysis and metrics that can address inequalities and climate injustice. To demonstrate the potential of the new dataset, we report examples of application to the Miami area, where the recent increased risk of floods and extreme events has exposed socially vulnerable populations to the consequences of climate change

Soluble cytochrome b5 from human erythrocytes

1. A hemeprotein with properties similar to microsomal cytochrome b5 has been detected in the supernatant fraction of hemolysates of human, beef, and rabbit erythrocytes. A method has been developed for determining the amount of this soluble cytochrome in small volumes of blood. The amount of the protein decreases during cell storage at 4 [deg]C. Blood cells rich in reticulocytes contain more of the protein than do mature cells.2. The cytochrome has been purified from human erythrocytes by a procedure which employs chromatography on Amberlite CG-50 and DETE-cellulose, ultrafiltration, and gel filtration. The purified protein sedimented in the ultracentrifuge as a single peak with an s20, w of 1.40. However, minor impurities were detected by polyacrylamide disc electrophoresis.3. The molecular weight of the purified protein has been calculated to be 14600 from sedimentation and diffusion measurements and 18400 as determined by gel filtration. The prosthetic group has been identified as protoheme IX. The spectral properties of the hemeprotein are those of a low spin heme complex. The EPR spectrum of the oxidized form shows g values of 3.03, 2.21, and 1.39 and the visible spectrum has a Soret absorbance maximum at 413 nm. The protein is reducible by dithionite or NADH plus cytochrome b5 reductase and the reduced form shows absorbance maxima at 423, 527, and 556 nm with a shoulder at 560 nm.4. The cytochrome b5 differs from the other B-type cytochrome of erythrocyte, S-protein (hemeprotein 559), and is not derived from this protein. The erythrocyte cytochrome b5 is similar to the cytochrome b5 solubilized from liver microsomes in terms of spectral properties, molecular weight, prosthetic group, and reactivity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34069/1/0000347.pd

Are Underserved Populations Left Out of National Flood Mitigation Efforts and Facing Greater Impact? A Method to Assess Racial Inequality at the Census Tract Level

Development policies have systematically relegated certain populations to undesirable locations including areas at risk of flooding. Over time many properties will no longer be inhabitable and others will see damage from significant flooding. Current U.S. federal policy funds flood risk mitigation measures, such as property acquisition, relocation, and retrofitting; however, depending on various factors at the subcounty level, these actions can in some contexts provide disproportionate benefit to higher income, mostly White areas, failing to appropriately benefit underserved and exposed populations. Here, we present an exploratory method, building off existing research on programmatic-wide and event-specific analysis to explore patterns allowing state- and county-level decision-makers to identify inequalities in federal funding, potentially supporting reprioritization. This work evaluates the National Flood Insurance Program (NFIP) claims data from 1975 to 2019 and Federal Emergency Management Agency (FEMA) mitigation efforts from 1989 to 2018 to explore the distribution of mitigation measures related to tract to county racial disproportionalities (for example, majority non-White census tracts in majority White counties). We find that for majority non-White census tracts in majority White counties, there are disproportionately fewer NFIP claims. This supports previous work, which shows lower levels of assistance in flood recovery, resilience, and preparedness in these areas

The effect of two different health messages on physical activity levels and health in sedentary overweight, middle-aged women

Background: Most public health guidelines recommend that adults need to participate in 30 minutes of moderate intensity physical activity on most days of the week to maintain good health. Achieving the recommended 30 minutes of exercise a day can be difficult in middle aged, overweight women. This 12 week study evaluated whether a 10,000 steps per day message was more effective than a 30 minutes a day message in increasing physical activity in low active, overweight women. Methods: Thirty participants were randomized into 2 groups: Group 1 was asked to undertake 30 minutes of walking/day, whereas Group 2 was asked to accumulate 10,000 steps/day using their pedometers. Results: Results showed that there were no changes in anthropometric and blood pressure measures between or within groups. However, the 10,000 step and the 30 minutes groups’ daily average number of steps/day were significantly higher than baseline at week 6 (p = 0.038 and p = 0.039 respectively) and at week 12 (p = 0.028 and p = 0.038 respectively). At week 12, the 10,000 steps group were taking an average of 4616 steps per day more (43% increase) than at baseline and the 30 minutes group were taking an average of 2761 steps per day more (35% increase) than at baseline. There was a significant difference in the number of steps with the 10,000 steps group versus 30 minutes group at 12 weeks (p = 0.045).Conclusions: This study found that low active, overweight women undertook significantly more physical activity when they had a daily 10,000 step goal using a pedometer, than when they were asked to achieve 30 minutes of walking/day. Therefore we suggest that a public health recommendation of “10,000 steps/day”, rather than the “30 min/day” could be applied to promote increased physical activity in sedentary middle aged women

Effect of physical activity intervention based on a pedometer on physical activity level and anthropometric measures after childbirth: a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Pregnancy and childbirth are associated with weight gain in women, and retention of weight gained during pregnancy can lead to obesity in later life. Diet and physical activity are factors that can influence the loss of retained pregnancy weight after birth. Exercise guidelines exist for pregnancy, but recommendations for exercise after childbirth are virtually nonexistent. The aim of this study was to evaluate the effect of physical activity intervention based on pedometer on physical activity level and anthropometric measures of women after childbirth.</p> <p>Methods</p> <p>We conducted a randomized controlled trial in which 66 women who had given birth 6 weeks to 6 months prior were randomly assigned to receive either a 12 week tailored program encouraging increased walking using a pedometer (intervention group, n = 32) or routine postpartum care (control group, n = 34). During the 12-week study period, each woman in the intervention group wore a pedometer and recorded her daily step count. The women were advised to increase their steps by 500 per week until they achieved the first target of 5000 steps per day and then continued to increase it to minimum of 10,000 steps per day by the end of 12^thweek. Assessed outcomes included anthropometric measures, physical activity level, and energy expenditure per week. Data were analyzed using the paired t-test, independent t-test, Mann-Whitney, chi-square, Wilcoxon, covariance analysis, and the general linear model repeated measures procedure as appropriate.</p> <p>Results</p> <p>After 12 weeks, women in the intervention group had significantly increased their physical activity and energy expenditure per week (4394 vs. 1651 calorie, <it>p </it>< 0.001). Significant differences between-group in weight (<it>P </it>= 0.001), Body Mass Index (<it>P </it>= 0.001), waist circumference (<it>P </it>= 0.001), hip circumference (<it>P </it>= 0.032) and waist-hip ratio (<it>P </it>= 0.02) were presented after the intervention. The intervention group significantly increased their mean daily step count over the study period (from 3249 before, to 9960 after the intervention, <it>p </it>< 0.001).</p> <p>Conclusion</p> <p>A physical activity intervention based on pedometer is an effective means to increase physical activity; reducing retention of weight gained during pregnancy and can improve anthropometric measures in postpartum women.</p> <p>Trial registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/IRCT201105026362N1">IRCT201105026362N1</a></p