834 research outputs found
Rapid automated measurement of body fat distribution from whole-body MRI
The accurate determination of a person’s total body fat is an important issue in medical analysis because obesity is a significant contributing factor to a variety of serious health problems. The medical literature identifies a wide range of diseases that are closely linked to obesity. Current methods of fat assessment are largely inaccurate, and most current methods of fat determination cannot show regional fat distribution, which is important in defining disease risk. We introduce a method that combines computer-aided techniques with whole-body MRI techniques and enables accurate quantification and visualization of total body fat burden and regional fat distribution. This technique may be important in identifying and treating at-risk populations
American Ginseng Modifies 137Cs-Induced DNA Damage and Oxidative Stress in Human Lymphocytes
The multifold bioactive medicinal properties of ginseng have been closely linked to its antioxidative ability, which is related to its ginsenoside content. Since the key mechanism of radiation-induced cell death and tissue damage is the generation of reactive oxygen species (ROS) that attack cellular DNA, this study focuses on the impact of a standardized North American ginseng extract (NAGE) on 137Cs-induced oxidative stress in human peripheral lymphocytes (PBL) obtained from 10 healthy individuals (6M/4F), 42.7 ± 4.6 years of age. At two different time points (0 h and 24 h before irradiation), we applied NAGE (250 - 1000 µg ml-1) to mononuclear cell cultures for cytokinesisblock micronuclei (MN) assay and determination of the state of oxidative stress in PBL. We found that at both time points, NAGE significantly reduced the MN yields in PBL after irradiation (1 and 2 Gy) in a concentration-dependent manner (P<0.001). Compared with radiation alone, the maximum reduction rate of MN yield were 51.1% and 49.1% after 1 Gy and 2 Gy exposures, respectively. We also found that before irradiation the presence of NAGE in the culture medium resulted in a significant increased intracellular total antioxidant capacity (TAC) in PBL. At both time points, the increment of 137Cs-induced MN yields in PBL was positively correlated with the increment of intracellular ROS production (R = 0.6 - 0.7, P = 0.002), but negatively correlated with the reduction of TAC levels (R = -0.4 - 0.5, P = 0.02 - 0.004). However, the presence of NAGE in the culture medium significantly increased the TAC levels, while concomitantly decreasing both ROS production and MN yields in PBL (P<0.001). Our findings that NAGE is effective in protecting human PBL against radiation-induced oxidative stress should encourage further in vivo study of dietary supplementation with NAGE as an effective natural radiation countermeasure. Originally published Open Nuclear Medicine Journal Vol 1 No. 1, 2009
Radioprotective Effect of American Ginseng on Human Lymphocytes at 90 Minutes Post-irradiation: A Study of 40 Cases
Backgroundâ Ionizing radiation (IR) initiates intracellular oxidative stress through enhanced
formation of reactive oxygen species (ROS) that attack DNA leading to cell death. As the diversity
of IR applied in medicine, agriculture, industry, and the growing threats of global terrorism, the
acquisition of radioprotectors is an urgent need for the nation. However, the applicability of
radioprotectors currently under investigation is limited due to their inherent toxicity.
Objectiveâ This study investigated the effect of a standardized North American ginseng extract
(NAGE, total ginsenoside content: 11.7%) on DNA damage in human lymphocytes at 90 min postirradiation.
Designâ With the application of NAGE (250 â 1000 μg mlâ 1) at 90 min post-irradiation (1 and 2
Gy), DNA damage in lymphocytes obtained from 40 healthy individuals was evaluated by
cytokinesis-block micronucleus (CBMN) assay. Similar experiments were also performed in
lymphocytes treated with WR-1065 (1 mM or 3mM). In addition, before and after irradiation,
lymphocytes obtained from 10 individuals were measured for their total antioxidant capacity (TAC)
and the reactive oxygen species (ROS).
Resultsâ The significant effect of NAGE against 137Cs-induced MN in lymphocytes is
concentration-dependent. NAGE (750 μg mlâ 1) reduced MN yield by 50.7% after 1 Gy and 35.9%
after 2 Gy exposures, respectively; these results were comparable to that of WR-1065. Further, we
also found that NAGE reduces MN yield and ROS but increases TAC in lymphocytes.
Conclusionsâ Our results suggest that NAGE is a relatively non-toxic natural compound that
holds radioprotective potential in human lymphocytes even when applied at 90 min post-irradiation.
One of the radioprotective mechanisms may be mediated through the scavenging of free radicals and
enhancement of the intracellular TAC. Originally published Journal of Alternative and Complementary Medicine Vol. 16, No. 5 2010
Is type II diabetes mellitus (NIDDM) a surgical disease?
Since February 1, 1980, 515 morbidly obese patients have undergone
the Greenville gastric bypass (GGB) operation. Of these,
212 (41.2%) were euglycemic, 288 (55.9%) were either diabetic
or had glucose intolerance, and 15 (2.9%) were unable to complete
the evaluation. After the operation, only 30 (5.8%) patients remained
diabetic (and 20 of these improved), 457 (88.7%) became
and have remained euglycemic, and inadequate data prevented
classification of the other 28 (5.4%). The patients who failed to
return to normal glucose values were older and their diabetes
was of longer duration than those who did. The effect of the
GGB was not only limited to the correction of abnormal glucose
levels. The GGB also corrected the abnormal levels of fasting
insulin and glycosylated hemoglobin in a cohort of 52 consecutive
severely obese patients with non-insulin-dependent diabetes. The
GGB effectively controls weight. If morbid obesity is defined as
100 pounds over ideal body weight, 89% of the patients are no
longer "morbidly" obese within 2 years. In most patients, the
control of the weight has been well maintained during the 11
years of follow-up; most of the upward creep in weight of 20.8%
between 24 and 132 months was from the 49 (9.5%) patients
who had staple line breakdowns between the large and small
gastric pouches. Non-insulin-dependent diabetes, previously
considered a chronic unrelenting disease, can be controlled in
the severely obese by the gastric bypass. Whether the correction
of glucose metabolism affects the complications of diabetes is
unknown. Whether the gastric bypass should be considered for
patients with advanced non-insulin-dependent diabetes but who
are not severely obese deserves consideration. The GGB has an
unacceptably high rate of staple line failure. Accordingly, the
authors have recently changed their procedure to one that divides
the stomach rather than partitions it with staples. Originally published Annals of Surgery, Vol. 215, No. 6, June 199
LC-HRMS suspect screening to show spatial patterns of New Psychoactive Substances use in Australia
New Psychoactive Substances (NPS) are an ever-changing class of compounds designed to imitate the effects of current recreational drugs. Such a diverse market is difficult to assess by traditional means, while collected information can become obsolete before it is available. Wastewater-based epidemiology is one technique which can capture information on where and when NPS appear at the community level. The aim of this study was to identify NPS in wastewater samples using a suspect screening approach. Weekend samples were collected from 50 wastewater treatment plants from Australian capital cities and regional areas across all eight States and Territories and screened against a database containing almost 200 NPS. A total of 22 different NPS were found across all regional and metropolitan wastewater treatment plants. Results showed that the most detected compounds were of the cathinone class, with both Alpha-PVP and methcathinone found in every region. In addition, five different synthetic cannabinoids were detected, at least once in half of the regions analysed. Herein, we report the first comprehensive nationwide analysis of NPS and show the utility of liquid chromatography-high resolution mass spectrometry screening for delivering spatial information of the NPS being consumed in communities
A multi-decade record of high quality fCO2 data in version 3 of the Surface Ocean CO2 Atlas (SOCAT)
The Surface Ocean CO2 Atlas (SOCAT) is a synthesis of quality-controlled fCO2 (fugacity of carbon dioxide) values for the global surface oceans and coastal seas with regular updates. Version 3 of SOCAT has 14.7 million fCO2 values from 3646 data sets covering the years 1957 to 2014. This latest version has an additional 4.6 million fCO2 values relative to version 2 and extends the record from 2011 to 2014. Version 3 also significantly increases the data availability for 2005 to 2013. SOCAT has an average of approximately 1.2 million surface water fCO2 values per year for the years 2006 to 2012. Quality and documentation of the data has improved. A new feature is the data set quality control (QC) flag of E for data from alternative sensors and platforms. The accuracy of surface water fCO2 has been defined for all data set QC flags. Automated range checking has been carried out for all data sets during their upload into SOCAT. The upgrade of the interactive Data Set Viewer (previously known as the Cruise Data Viewer) allows better interrogation of the SOCAT data collection and rapid creation of high-quality figures for scientific presentations. Automated data upload has been launched for version 4 and will enable more frequent SOCAT releases in the future. High-profile scientific applications of SOCAT include quantification of the ocean sink for atmospheric carbon dioxide and its long-term variation, detection of ocean acidification, as well as evaluation of coupled-climate and ocean-only biogeochemical models. Users of SOCAT data products are urged to acknowledge the contribution of data providers, as stated in the SOCAT Fair Data Use Statement. This ESSD (Earth System Science Data) “living data” publication documents the methods and data sets used for the assembly of this new version of the SOCAT data collection and compares these with those used for earlier versions of the data collection (Pfeil et al., 2013; Sabine et al., 2013; Bakker et al., 2014). Individual data set files, included in the synthesis product, can be downloaded here: doi:10.1594/PANGAEA.849770. The gridded products are available here: doi:10.3334/CDIAC/OTG.SOCAT_V3_GRID
Real-Time Detection and Filtering of Radio Frequency Interference On-board a Spaceborne Microwave Radiometer: The CubeRRT Mission
The Cubesat Radiometer Radio frequency interference Technology validation mission (CubeRRT) was developed to demonstrate real-time on-board detection and filtering of radio frequency interference (RFI) for wide bandwidth microwave radiometers. CubeRRT’s key technology is its radiometer digital backend (RDB) that is capable of measuring an instantaneous bandwidth of 1 GHz and of filtering the input signal into an estimated total power with and without RFI contributions. CubeRRT’s on-board RFI processing capability dramatically reduces the volume of data that must be downlinked to the ground and eliminates the need for ground-based RFI processing. RFI detection is performed by resolving the input bandwidth into 128 frequency sub-channels, with the kurtosis of each sub-channel and the variations in power across frequency used to detect non-thermal contributions. RFI filtering is performed by removing corrupted frequency sub-channels prior to the computation of the total channel power. The 1 GHz bandwidth input signals processed by the RDB are obtained from the payload’s antenna (ANT) and radiometer front end (RFE) subsystems that are capable of tuning across RF center frequencies from 6 to 40 GHz. The CubeRRT payload was installed into a 6U spacecraft bus provided by Blue Canyon Technologies that provides spacecraft power, communications, data management, and navigation functions.
The design, development, integration and test, and on-orbit operations of CubeRRT are described in this paper. The spacecraft was delivered on March 22nd, 2018 for launch to the International Space Station (ISS) on May 21st, 2018. Since its deployment from the ISS on July 13th, 2018, the CubeRRT RDB has completed more than 5000 hours of operation successfully, validating its robustness as an RFI processor. Although CubeRRT’s RFE subsystem ceased operating on September 8th, 2018, causing the RDB input thereafter to consist only of internally generated noise, CubeRRT’s key RDB technology continues to operate without issue and has demonstrated its capabilities as a valuable subsystem for future radiometry missions
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