RS Levels Research Articles

No-Tillage Treatment with Total Green Manure Mulching Reduces Soil Respiration by Regulating Soil Water Content Affecting Heterotrophic Respiration

Green manure is widely applied in agricultural production due to its beneficial soil modification and fertilization effects. However, the mechanisms underlying the effects of green manure return methods on soil respiration (Rs) and its components remain unclear. This study aimed to investigate the effects of green manure return methods on Rs in maize fields by quantifying Rs levels. A field experiment was conducted from 2021 to 2023 in the inland river oasis irrigation area of Gansu, with five treatment conditions: tillage with a full quantity of green manure incorporated into the soil (TG), no tillage with a full quantity of green manure mulched on the soil surface (NTG), tillage with roots incorporated into the soil and above-ground green manure removed (T), no tillage with above-ground manure removed (NT), and conventional tillage and leisure (CT). The results showed that, compared with CT, the NTG treatment increased the maize grain yield while reducing the soil heterotrophic respiration rate (Rh) by 8.5–9.8% and Rs by 6.7–8.7%, but did not significantly affect the soil autotrophic respiration rate (Ra), and decreased the carbon emission efficiency (CEE) by 20.8–25.6%. The increase in the soil water content (SWC) significantly reduced Rh during all growth periods, which was the primary factor in the reduction of Rs. Additionally, the net ecosystem productivity carbon sequestration (NEP-C) of the farmland ecosystem was positive under this system, indicating that the soil acts as a carbon “sink”. Therefore, a no-tillage treatment with a full quantity of green manure mulched on the soil surface can be used as a reasonable green manure return method to reduce carbon emissions from farmland in arid oasis irrigation regions.

Comparative study: how dry heating treatment and annealing influence the multi-structure, physicochemical properties and in vitro digestibility of black highland barley starch.

In this study, comparative investigation on the effect of dry heating treatment (DHT) and annealing (ANN) on multi-structure, physicochemical properties and in vitro digestibility of black highland barley (BHB) starch was done. Results revealed that both DHT and ANN did not affect the "A"-type crystalline pattern and FT-IR spectroscopy of BHB starch, but changed the morphology, raised water absorption capacity and lowered viscosities. Compared to native starch, DHT- and ANN-modified samples had totally opposite alteration trends in amylose content, color characteristics, oil absorption capacity, gelatinization parameters and pasting temperature. These changes were positively related to treatment temperature and time for DHT-modified starches, while which were dependant on treatment duration for ANN-modified starches. Total in vitro hydrolysis rate and rapidly digestive starch content in starch markedly raised after DHT, whereas slowly digestive starch and RS levels decreased. Nevertheless, ANN significantly improved the hydrolyzation stability with treatment time prolonging, especially increased RS content and lowered RDS level. Therefore, this study identified both DHT and ANN were effective methods to alter the properties of BHB starch, and more importantly, they had distinguishing influence by different mechanisms, which would remind user to select appropriate means for physical starch modification based on different application purposes.

Improvement of Prebiotic Properties and Resistant Starch Content of Corn Flour (Zea mays L.) Momala Gorontalo Using Physical, Chemical and Enzymatic Modification.

Probiotics are a non-digestible food ingredient that promotes the growth of beneficial microorganisms in the intestines. One of the functional food ingredients, Momala corn flour, is a source of prebiotics with a resistant starch content of 4.42%. Thi s study aimed to improve the prebiotic properties and resistant starch content of modified corn flour (MCF) Momala Gorontalo by using physical, chemical, and enzymatic modification processes. The research methods include physical modification (heat moisture treatment, annealing, autoclaving-cooling cycling, microwave), chemical modification (acid hydrolysis), and enzymatic modification (debranching pullulanase). The results showed that the modified by heat moisture treatment (HMT) increased RS levels 1-fold, annealing modification (ANN) 8.9-fold, autoclaving-cooling one cycle modification (AC-1C) 2.9-fold, autoclaving-cooling two cycles modification (AC-2C) 2.0-fold, microwave modification (MW) 1.3-fold, acid hydrolysis (HA) modification 5.0-fold, and debranching pullulanase (DP) modification 3.8-fold compared with corn flour control without modification. The value of the prebiotic activity of MCF hydrolysed acid (HA) is 0.03, and debranching pullulanase (DP) is 0.02 against Enteropathogenic Escherichia coli (EPEC). The prebiotic effect value of MCF HA and DP were 0.76 and 0.60, respectively. The prebiotic index value of MCF HA and DP were 0.60 and 0.48, respectively. This study confirms that MCF HA and DP are good prebiotic candidates because they have resistant starch content, low starch digestibility, and resistance to simulated gastric fluid hydrolysis than unmodified corn flour.

A Novel Machine Learning Approach for Solar Radiation Estimation

Solar irradiation (Rs) is the electromagnetic radiation energy emitted by the Sun. It plays a crucial role in sustaining life on Earth by providing light, heat, and energy. Furthermore, it serves as a key driver of Earth’s climate and weather systems, influencing the distribution of heat across the planet, shaping global air and ocean currents, and determining weather patterns. Variations in Rs levels have significant implications for climate change and long-term climate trends. Moreover, Rs represents an abundant and renewable energy resource, offering a clean and sustainable alternative to fossil fuels. By harnessing solar energy, we can actively reduce greenhouse gas emissions. However, the utilization of Rs comes with its own challenges that must be addressed. One problem is its variability, which makes it difficult to predict and plan for consistent solar energy generation. Its intermittent nature also poses difficulties in meeting continuous energy demand unless appropriate energy storage or backup systems are in place. Integrating large-scale solar energy systems into existing power grids can present technical challenges. Rs levels are influenced by various factors; understanding these factors is crucial for various applications, such as renewable energy planning, climate modeling, and environmental studies. Overcoming the associated challenges requires advancements in technology and innovative solutions. Measuring and harnessing Rs for various applications can be achieved using various devices; however, the expense and scarcity of measuring equipment pose challenges in accurately assessing and monitoring Rs levels. In order to address this, alternative methods have been developed with which to estimate Rs, including artificial intelligence and machine learning (ML) models, like neural networks, kernel algorithms, tree-based models, and ensemble methods. To demonstrate the impact of feature selection methods on Rs predictions, we propose a Multivariate Time Series (MVTS) model using Recursive Feature Elimination (RFE) with a decision tree (DT), Pearson correlation (Pr), logistic regression (LR), Gradient Boosting Models (GBM), and a random forest (RF). Our article introduces a novel framework that integrates various models and incorporates overlooked factors. This framework offers a more comprehensive understanding of Recursive Feature Elimination and its integrations with different models in multivariate solar radiation forecasting. Our research delves into unexplored aspects and challenges existing theories related to solar radiation forecasting. Our results show reliable predictions based on essential criteria. The feature ranking may vary depending on the model used, with the RF Regressor algorithm selecting features such as maximum temperature, minimum temperature, precipitation, wind speed, and relative humidity for specific months. The DT algorithm may yield a slightly different set of selected features. Despite the variations, all of the models exhibit impressive performance, with the LR model demonstrating outstanding performance with low RMSE (0.003) and the highest R2 score (0.002). The other models also show promising results, with RMSE scores ranging from 0.006 to 0.007 and a consistent R2 score of 0.999.

Long-Term Consumption of Resistant Starch Induced Changes in Gut Microbiota, Metabolites, and Energy Homeostasis in a High-Fat Diet.

Considering that the study on the impact of the long-term consumption of resistant starch on metabolic syndromes induced by a high-fat diet (HFD) is rare, this investigation designed a 36-week consumption of HFD containing three RS levels (LRS, MRS, and HRS) for measuring changes in serum parameters, liver transcriptome, and gut microbiota. Results indicated that all levels of RS in HFD significantly reduced food intakes and body gain, followed by increased leptin and PYY, but did not show dose-dependence. Furthermore, MRS triggered a greater number of enriched pathways than the other RS groups, whereas no enriched pathway was noted in the HRS group. The Firmicutes/Bacteroidetes ratio can still predict changes in body weight for long-term observation, and isobutyrate was found to be positively related to Blautia. Importantly, a shifted ratio of Ruminococcaceae/Lactobacillaceae quickly occurred in the early stage of 12 weeks for all groups, but the ratio remained constant in HRS rather than in LRS and MRS, which might indicate both similarity and difference in the regulation of the metabolic syndromes among the three RS interventions.

Effect of heat moisture treatment on resistant starch content among carbohydrate sources: a meta‐analysis

SummaryResistant starch (RS) can be generated through heat moisture treatment (HMT). The HMT was conducted by modifying starch using different ratio of moisture content, high temperature and heating time. A number of studies showed that the effects of HMT on RS contents in cereals, pulses, tubers and fruits were inconsistent. This study aimed to analyse the impact of HMT on RS level in various carbohydrate sources through a meta‐analysis approach. Study selection was conducted with the PRISMA method. There were 21 relevant studies and 67 data used for meta‐analysis. The database was analysed by using Hedges’ d. The results showed that there was a significant impact of HMT on RS level of cereals, especially wheat. The highest increase in RS levels for various carbohydrate sources in starch was influenced by the interaction of treatment between water content at 15 ≤ x < 25%, heating time at 0.25 < x ≤ 6 h and temperature at 120 ≤ x ≤ 130 °C.

Assessing self-criticism and self-reassurance: Examining psychometric properties and clinical usefulness of the Short-Form of the Forms of Self-Criticizing/Attacking & Self-Reassuring Scale (FSCRS-SF) in Spanish sample.

The Forms of Self-Criticizing/Attacking and Self-Reassuring Scale (FSCRS) was designed to measure self-criticism (SC) through Inadequate Self (IS) and Hated Self (HS) factors, as well as self-reassurance (RS). However, its long and short forms have yet to be validated in the Spanish Population. The present study examines the psychometric properties of the short form (FSCRS-SF) and its clinical usefulness in a sample of 576 adult individuals, 77 with psychiatric disorders and 499 without. Non-clinical participants were split according to their previous experience with meditation (active meditators, n = 133; non-active meditators, n = 41; and non-meditators, n = 325) and differences between these subgroups were explored. Additionally, a subsample of 20 non-clinical participants took part in a mindfulness- and compassion- based intervention (MCBI) to assess the usefulness of the scale as an outcome measure. Results confirmed the original three-factorial structure, good internal consistency, acceptable test-retest reliability, and a pattern of correlations consistent with previous literature. Regarding differences between groups, the clinical subsample showed significant higher SC and lower RS levels than non-clinical participants and active meditators had significant lower IS and higher RS levels than non-meditators. Participants who participated in the MCBI showed significant RS improvement and a decrease in IS and HS levels. Moreover, a hierarchical multiple regression showed that RS made a significant predictive contribution to distress at three months’ time. In conclusion, results show that the Spanish version of the FSCRS-SF is a reliable and valid measure of SC and RS in non-clinical populations and an adequate instrument to detect changes after MCBIs.

High Rainfall Inhibited Soil Respiration in an Asian Monsoon Forest in Taiwan

Soil respiration represents the second largest carbon flux, next to photosynthesis of the terrestrial biosphere, and thus plays a dual role in regional and global carbon cycles. However, soil respiration in Asian monsoon forests with high rainfall has rarely been studied. In this study, we continuously measured soil respiration using a 12-channel automated chamber system in a 61-year-old Japanese cedar forest in central Taiwan with annual rainfall greater than 2500 mm. A 4-year (2011–2014) continuous half-hourly dataset was used to quantify the influences of soil temperature and moisture, especially rainfall events, on both total soil respiration (Rs) and heterotrophic respiration (Rh). The annual mean Rs was approximately 10.8 t C ha−1 (ranging from 10.7 to 10.9) t C ha−1, with Rh contributing approximately 74.6% (ranging from 71.7% to 80.2%). Large seasonal variations in both Rs and Rh were primarily controlled by soil temperature. Over 45.8% of total annual rainfall amounts were provided by strong rainfall events (over 50 mm), and over 40% of rainfall events occurred during summers between 2012 and 2014. These strong rainfall events caused rainwater to enter soil pores and cover the soil surface, which resulted in limited soil microorganism activity and, consequently, restricted CO2 production. The mean Q10 values were 2.38 (ranging from 1.77 to 2.65) and 2.02 (ranging from 1.71 to 2.34) for Rs and Rh, respectively. The Q10 values in this study, which were lower than in global forest ecosystems, may imply that the interannual Rs values observed in this study that were caused by high rainfall were less temperature-dependent than the Rs levels in global forest ecosystems. Both Rs and Rh were negatively correlated with soil moisture, which indicated that the soil moisture levels in the studied forest were usually under saturated conditions. These results also provide the lack of data for respiration in the Asian monsoon region under high-rainfall conditions.

Experimental design applied in the semolina pasta cooking to increase the resistant starch formation

Pasta that undergoes the cooking exhibits several structural changes that can mainly affect protein and starch availability. In this study a central composite rotatable design (CCRD) 22 was applied to find the best cooking times and pasta:water ratios to prepare commercial semolina pasta (spaghetti) to increase RS levels. Time intervals applied to cooking ranged from 7 to 13 min while the pasta:water ratio ranged from 1:33 to 1:4 (m v−1; g mL−1). Composition of the spaghetti samples was also determined. Cooking times strongly influenced RS formation and water absorption (WA) capacity, since there was mean decrease of 17% in WA and increase of 164% in the RS content when both extreme points (−1.41 and + 1.41) of the experimental design where applied. Protein and ash contents also affected the RS level. Cooking time between 7 and 10 min and pasta:water ratios (from 1:4 to 1:10, m v−1) enabled satisfactory RS contents (from 72.2 to 138.0 mg g−1), which should improve the functional fiber content in the pasta.

Dietary resistant starch preserved through mild extrusion of grain alters fecal microbiome metabolism of dietary macronutrients while increasing immunoglobulin A in the cat.

Dietary digestion-resistant starch (RS) provides health benefits to the host via gut microbiome-mediated metabolism. The degree to which cats manifest beneficial changes in response to RS intake was examined. Healthy cats (N = 36) were fed identically formulated foods processed under high (n = 17) or low (n = 19) shear extrusion conditions (low and high RS levels [LRS and HRS], respectively). Fecal samples collected after 3 and 6 weeks' feeding were assayed for stool firmness score, short-chain fatty acids, ammonia, and changes to the global metabolome and microbiome; fecal immunoglobulin A (IgA) was analyzed at week 6. Few differences were seen in proximate analyses of the foods; stool firmness scores did not differ. In cats consuming HRS food, concentrations of fecal butyrate and the straight chain:branched chain fatty acid ratio were significantly greater in feces at both weeks 3 and 6, while fecal ammonia was reduced at week 6 relative to feces from LRS-fed cats. Fecal IgA concentrations were significantly higher at week 6 with HRS food. RS consumption altered 47% of the fecal metabolome; RS-derived sugars and metabolites associated with greater gut health, including indoles and polyamines, increased in the cats consuming HRS food relative to those fed the LS food, while endocannabinoid N-acylethanolamines decreased. Consumption of HRS food increased concentrations of the ketone body 3-hydroxybutyrate in feces and elevated concentrations of reduced members of NADH-coupled redox congeners and NADH precursors. At the microbiome genus-level, 21% of operational taxonomic units were significantly different between food types; many involved taxa with known saccharolytic or proteolytic proclivities. Microbiome taxa richness and Shannon and Simpson alpha diversity were significantly higher in the HRS group at both weeks. These data show that feline consumption of grain-derived RS produces potentially beneficial shifts in microbiota-mediated metabolism and increases IgA production.

Efficacy of Erymicin 200 Injections for Reducing Renibacterium salmoninarum and Controlling Vertical Transmission in an Inland Rainbow Trout Brood Stock.

Bacterial Kidney Disease, caused by Renibacterium salmoninarum (Rs), is widespread and can cause significant mortality at most life stages in infected salmonids. Rs is commonly found in inland trout, which can be carriers of the bacterium. Lethal spawns can be used to control vertical transmission to progeny through the culling of eggs from infected parents, but can be costly, time-consuming, and can negatively impact important and rare brood stocks. Erymicin 200 is an Investigational New Animal Drug (INAD) intended to reduce Rs levels in hatchery brood stocks and control vertical transmission to progeny. We tested the efficacy of Erymicin 200 injections in a positive, hatchery-resident rainbow trout (Oncorhynchus mykiss) brood stock in Colorado, USA. Brood fish age two and three were injected with 25 mg per kg of body weight Erymicin 200 three times prior to spawning. Erymicin 200 was effective in reducing Rs to below detectable levels in treated fish. However, both negative treated and control brood fish produced positive progeny, suggesting that Erymicin 200 did not prevent the vertical transmission of Rs.

Physical modification of starch: changes in glycemic index, starch fractions, physicochemical and functional properties of heat-moisture treated buckwheat starch.

Native buckwheat starch was extracted and modified by heat-moisture treatment (HMT) with different treatment time (15, 30 and 45min) to investigate its effect on physicochemical, morphological, functional properties, starch profile (rapidly digestible starch, RDS; slowly digestible starch, SDS and resistant starch, RS fractions) and expected glycemic index (eGI). Results revealed that with increasing time duration of HMT from 15 to 45min, amylose content, pasting temperature and thermostability increased substantially whereas swelling power, solubility and viscosity parameters decreased. The SEM micrographs showed that HMT caused fissures in the granule and surface indentation. HMT-45 (starch treated for 45 min) had the lowest RDS content (29.33%) and the highest SDS (51.30%) and RS (8.21%) levels. The decreased hydrolysis rate, high amylose and RS content of HMT-45 resulted in a significant decrease in estimated glycemic index (eGI) values from 51.49% (Native) to 44.16% (HMT-45) thus indicating its role in prevention of non-insulin- dependent diabetes.

Assessing the toxicant effect of spontaneously volatilized 4-vinylcyclohexane exposure in nymphs of the lobster cockroach nauphoeta cinerea

Vinylcyclohexene (VCH) is an environmental contaminant well known for its ovotoxicant effects in several organisms. However, the mechanisms underlying the toxicity of VCH as well as its harmful effects toward other organs are until unclear. In this work, we assess some endpoint signals of toxicity induced by volatilized VCH exposure using nymphs of the lobster cockroach Nauphoeta cinerea. Nymphs were exposed to VCH via inhalation for 70 days. The levels of volatilized VCH were quantified by headspace gas chromatography and the concentration varied between 3.41 and 7.03 nmol/μl. VCH inhalation caused a reduction of 35% in the survival rate of the exposed animals. Nymphs exposed to volatilized VCH for 35 and 70 days had a reduction in the body weight gain of 1.8− and 2.6−fold, respectively with a reduction in dissected head, fat body, and maturing reproductive organs. The exposure did not change water consumption, excepting on the 20th day (with a 3-fold change) and decreased the food intake significantly. Regarding biochemical markers, we found that the activity of GST from the dissected organs was increased by volatilized VCH after both 35 and 70 days of exposure. The fat body presented the most prominent GST activity especially after 35 days of exposure with 1.6-fold higher than the control group. Exposure also caused an increase in RS levels in the fat body of 1.35-fold and 1.47-fold after 35 and 70 days, respectively and did not affect the activity of the AChE from the head. Our findings support the harmful impact of volatilized VCH inhalation, highlighting the cockroach N.cinerea as a valuable insect model to investigate environmental toxicants.

Interactions among yeast and probiotic bacteria enhance probiotic properties and metabolism offering augmented protection to Artemia franciscana against Vibrio anguillarum

The interactions of the probiotics Bacillus subtilis, Lactococcus lactis and Lactobacillus plantarum with the yeast Saccharomyces cerevisiae were examined in terms of probiotic and biochemical characteristics. Yeast supernatant had a positive effect on the aggregation biofilm formation capacity and hydrophobicity of probiotics, and resulted in increased lactic acid levels, reduced pH values as well as lower RS and FAN levels of probiotics. The effect of probiotics supernatants on yeast was more complex but best results were obtained in the yeast: probiotic CFS ratio of 1:2 for B. subtilis and of 2:1 for the other probiotics. The observed effects depended on the volume ratio of the cell free supernatant to the culture it was applied on. Best results were obtained by the volume ratio probiotic: yeast of (2:1) for B. subtilis and of (1:2) probiotic: yeast for L. plantarum and L. lactis. These ratios were used for further evaluation in vitro against V. anguillarum, resulting in reduced survival and attachment properties of the pathogen. Moreover, the administration of the corresponding combination of bacteria and yeast to Artemia nauplii greatly improved their survival following a challenge with the pathogen. Our results demonstrate that yeast enhances the protective effect of probiotics in a strain specific manner.

Expression of reactive species related genes is associated with patient survival in luminal B breast cancer.

Increased reactive species (RS; reactive oxygen and nitrogen species) are a byproduct of both enzymatic and non-enzymatic systems, and critical in cancer development, including breast tumorigenesis. To investigate the role of RS-related genes in breast cancer, expression levels of the most common annotated genes involved in regulating cellular RS levels and proteins that are substrates of RS in specific subtypes of breast cancer 9 were evaluated using public data bases. Based on the premise that increased RS promote tumor formation, and breast cancer subtypes vary in aggressiveness, we hypothesized that specific RS gene expression signatures are associated with breast cancer aggressiveness and patient survival. We identified a group of genes (GSTK1, PRDX2, PRDX3 and SLC36A1) that differentiate Luminal B tumors in two clusters and predict survival of patients with Luminal B breast cancers. Furthermore, network analyses of these four genes revealed an overlap of known LumB related pathways with those of RS-related signaling, which included regulation of M-phase and mitochondrial functions.

Contrasting responses of heterotrophic and root-dependent respiration to soil warming in a subtropical plantation

The most advanced global land models remain highly uncertain in their predictions of the magnitude and direction of the effects of global warming on soil respiration. To better understand how soil respiration responds to warming, we conducted a three-year soil warming experiment in a subtropical Castanopsis hystrix plantation. Soil respiration (Rs) is considered the sum of root-dependent respiration (Rrd) and heterotrophic respiration (Rh). We estimated root-dependent respiration using the difference in soil respiration between trenched (100cm deep) and non-trenched plots. Our results showed that soil moisture was significantly higher in the trenched than non-trenched subplots in the second year, but not in the third year. Soil warming increased Rh, and suppressed Rrd. The responses of Rh and Rrd to soil warming varied with the seasons, being greater in the dry–cool than in the wet–warm season. The elevated Rh levels may have resulted from the increased soil temperature and decreased soil moisture due to warming. The decline in soil total nitrogen (STN) content attributed to soil warming decreased arbuscular mycorrhizal fungi (AMF) biomass, which led to the reduced Rrd. The decreased Rrd and increased Rh appear to have offset each other, resulting in unaltered Rs levels under the warming treatment. Our study shows that mycorrhizal colonization can have similar effects on soil carbon as it does abiotic environmental factors such as temperature and moisture, and affects Rs dynamics.

Effect of acid-ethanol treatment and debranching on the structural characteristics and digestible properties of maize starches with different amylose contents

In this study, maize starches with different amylose contents were modified by acid-ethanol treatment (AET) to various degrees, followed by debranching and then recrystallization through temperature cycling to produce resistant starch type III (RS3). The structural characteristics and digestible properties of the AET-debranched starches were investigated. The result indicated significant reductions in amylose and long side-chain length in high-amylose maize starch (HMS) and normal maize starch (NMS), but minor variations in the chain-length distribution in waxy maize starch (WMS). All three maize starches exhibited increased relative crystallinities and RS levels following moderate AET; however, the increment varied according to starch types. The highest RS contents of HMS, NMS, and WMS at 66.8%, 58.7%, and 68.4% were obtained after 8 h, 24 h, and 14 h of AET, respectively. These results indicated that the appropriate reduction in chain length following AET and prior to debranching was beneficial to RS3 formation.

Improving gel formation of rice starch added with cross‐linked resistant starch prepared from rice starch

The gel formation properties of non‐waxy rice starch with cross‐linked resistant starch with phosphate (RS4, 10, 20, and 30% based on rice starch) prepared from three rice varieties with different amylose (AM) content were investigated to increase dietary fiber content, improve gel structure, and reduce the glycemic index of rice products. The AM contents of rice starches were 1.71% in Hanganchal1, 22.47% in Nampyeong, and 33.39% in Goamy. All RS4 showed A‐type crystallinity and their RS levels were 46.91, 54.54, and 66.01%, respectively. The initial pasting temperatures of RS4 added rice starches increased as RS4 contents increased, but peak and breakdown viscosities and enthalpy change (△H) reduced. The RS4 addition improved gel shape and texture properties including hardness, cohesiveness, and gumminess, except the 30% Goamy RS4 added gel. The 20% RS4 addition was appropriate to form rice starch gels. The network structure of RS4 added gel formed more regular and firmer than that of control, because RS4 granules were entrapped within the gel matrix like observed by light microscope and scanning electron microscopy. It is suggested that RS4 not only assist in forming a rigid network structure but also increasing a dietary fiber content.

Organoselenium Bis Selenide Attenuates 3-Nitropropionic Acid-Induced Neurotoxicity in Rats

This study was designed to evaluate the effects of bis selenide on Huntington disease (HD)-like signs induced by 3-nitropropionic acid (3-NP) in rats. To this aim, rats were treated for 4days with bis selenide (5 or 20mg/kg/day, per oral) 30min before 3-NP (20mg/kg/day, intraperitoneally). The body weight gain, locomotor activity, motor coordination, and biochemical parameters in striatal preparations were assessed 24h after the last injection of 3-NP. The highest dose of bis selenide was effective in protecting against body weight loss and motor coordination deficit induced by 3-NP. The impairment of locomotor activity caused by 3-NP was abolished by bis selenide at both doses. Bis selenide (5 and 20mg/kg) partially restored succinate dehydrogenase activity inhibited after 3-NP exposure. The dose of 20mg/kg of bis selenide recovered partially δ-aminolevulinic acid dehydratase activity, and totally Na(+), K(+)-ATPase activity, two sulfhydryl enzymes sensitive to oxidizing agents, which had their activities inhibited by 3-NP. Also, 3-NP led to an increase in protein carbonyl levels and glutathione reductase activity and inhibited catalase activity-alterations that were reversed by bis selenide administration at both doses. The highest dose of bis selenide was effective against the increase of RS levels, the depletion of reduced glutathione content, and the inhibition of glutathione peroxidase activity induced by 3-NP. Bis selenide was not effective against inhibition of SOD activity caused by 3-NP. These findings demonstrate that bis selenide elicited protective effects against HD-like signs induced by 3-NP in rats.

P1-07-11: Consistency and Control in Clinical Assay Technology over Time: The Oncotype DX Recurrence Score and Assessment of Single Gene Expression Levels.

Abstract Background: ASCO® and CAP have recently highlighted the importance of consistency and control in clinical assay technology. To date the Oncotype DX® Recurrence Score® (RS) has been ordered to assist in individualized treatment decision making in over 200,000 estrogen receptor positive, early stage breast cancer patients. The assay quantifies gene expression using RT-PCR from fixed paraffin embedded tissue (FPET) and employs a large number of controls and calibrators to enhance precision and reproducibility. Over 6 years of data on the assay presents an opportunity to explore consistency over time in the RS and quantitative single gene levels (ER, PR, HER2). Methods: All tumors successfully analyzed in the Genomic Health Laboratory from 1/1/05-3/31/11 were included. Descriptive statistics for the RS, the average reference gene expression level, and expression levels for quantitative single genes were obtained for each calendar year. This was done for the entire data set as well as for subgroups defined by histological tumor type. The associations by year between HER2 and GRB7, ER and HER2, and ER and PR expression levels were explored including scatterplots and summary statistics. Results: There were a total of 207,691 breast cancer cases, and the number in each calendar year increased over time as shown in the Table. In general the median age increased slightly over time, as did the proportion of patients in the low RS Risk Group. There was no systematic change over time in the average reference gene expression level, or in the expression levels for the individual genes ER, PR or HER2 during the period from 2008 to 2011 when individual gene testing was provided as part of the Oncotype DX assay report. The relationships between HER2 and GRB7, ER and HER2, and ER and PR remained consistent over time. Conclusions: Active monitoring of the Oncotype DX assay as mandated by ASCO/CAP shows a high degree of consistency in results for both the multigene Recurrence Score and the quantitative single gene results. These results and the approaches used for monitoring consistency are relevant to other institutions in their efforts to maintain and improve assay quality control. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-07-11.