Validasi Metode dan Penetapan Kadar Nitrit (NO2) pada Hasil Rebusan Sayuran Hijau (Kangkung, Brokoli, Seledri) Menggunakan Spektrofotometer UV-Vis

Telah dilakukan penelitian tentang penetapan kadar nitrit (NO2) pada beberapa sayuran yaitu kangkung, brokoli, dan seledri. Sayur kangkung diperoleh dari kebun warga daerah Kenten, Palembang, sedangkan sayur brokoli dan seledri diperoleh dari salah satu swalayan di kota Palembang. Kandungan nitrit ditentukan dari hasil air rebusan sampel sayuran dengan metode spektrofotometer UV-Vis. Dari hasil penelitian ini diperoleh nilai kandungan nitrit untuk hasil air rebusan sayuran dengan variasi waktu 5, 15, 20, 25, dan 30 menit. Untuk hasil air rebusan sayur kangkung diperoleh 0,664 mg/kg; 0,665 mg/kg; 0,685 mg/kg; 0,702 mg/kg; 0,710mg/kg. Untuk hasil air rebusan sayur brokoli diperoleh 0,646 mg/kg; 0,647 mg/kg; 0,650 mg/kg; 0,680 mg/kg; 0,704 mg/kg. Untuk hasil air rebusan sayur seledri diperoleh 0,718 mg/kg; 0,730 mg/kg; 0,818 mg/kg; 0,821 mg/kg; 0,849 mg/kg. Dari hasil perebusan pada sayuran kangkung, brokoli, seledri masih aman sesuai dengan ketentuan ADI (Acceptable Daily Intake)/ jumlah asupan harian menurut WHO (World Health Organization)

Impact of Baseline Magnetic Resonance Imaging on Neurologic, Functional, and Safety Outcomes in Patients With Acute Traumatic Spinal Cord Injury

Study Design: Systematic review. Objective: To perform a systematic review to evaluate the utility of magnetic resonance imaging (MRI) in patients with acute spinal cord injury (SCI). Methods: An electronic search of Medline, EMBASE, the Cochrane Collaboration Library, and Google Scholar was conducted for literature published through May 12, 2015, to answer key questions associated with the use of MRI in patients with acute SCI. Results: The literature search yielded 796 potentially relevant citations, 8 of which were included in this review. One study used MRI in a protocol to decide on early surgical decompression. The MRI-protocol group showed improved outcomes; however, the quality of evidence was deemed very low due to selection bias. Seven studies reported MRI predictors of neurologic or functional outcomes. There was moderate-quality evidence that longer intramedullary hemorrhage (2 studies) and low-quality evidence that smaller spinal canal diameter at the location of maximal spinal cord compression and the presence of cord swelling are associated with poor neurologic recovery. There was moderate-quality evidence that clinical outcomes are not predicted by SCI lesion length and the presence of cord edema. Conclusions: Certain MRI characteristics appear to be predictive of outcomes in acute SCI, including length of intramedullary hemorrhage (moderate-quality evidence), canal diameter at maximal spinal cord compression (low-quality evidence), and spinal cord swelling (low-quality evidence). Other imaging features were either inconsistently (presence of hemorrhage, maximal canal compromise, and edema length) or not associated with outcomes. The paucity of literature highlights the need for well-designed prospective studies. © 2017, © The Author(s) 2017

Differences in Hand Grip Strength in Division I Male Student-Athletes Across Multiple Sports

Hand grip strength (HGS) is often used as a marker of hand and forearm muscular strength, but also as an indirect gauge of upper-body muscular strength and shoulder stability. For sport athletes that utilize grasping actions (e.g., tennis, lacrosse, wrestling), HGS measures can be used to help guide programming to increase strength and stability of the upper extremity and to monitor progress through rehabilitation programs following upper extremity injury. However normative values for HGS for different sport athletes are scarce. PURPOSE: The purpose of this study was to compare potential differences between bilateral HGS across multiple sports in Division I male student-athletes. METHODS: During a preseason screening, 146 Division I male student athletes (19.9 ± 1.5 y, 182.3 ± 8.0 cm, 83.2 ± 11.1 kg) volunteered to complete a standard hand-grip test. A hand-held dynamometer was used to determine HGS for the right (HG-R) and left (HG-L) hands using standard procedures. The highest of three trials was recorded for each hand. One-way ANOVAs with Tukey’s post-hoc test were conducted to assess differences across the different sport athletes using SPSS v30 (a = 0.05). RESULTS: Normative data showed significant differences in HG-R and HG-L across sports (F[5] = 3.940, p = 0.002 and F[5] = 5.871, p \u3c 0.001, respectively). Wrestlers had the highest HG-R and HG-L (52.1 ± 10.1 and 51.9 ± 8.1 kg), whereas tennis had the lowest HG-R and HG-L (42.7 ± 4.2 and 35.7 ± 5.0 kg, respectively). Wrestlers had significantly higher HG-R than basketball and soccer, and significantly higher HG-L than soccer, tennis, and lacrosse (p \u3c 0.05). Male tennis athletes had significantly lower HG-L than basketball, baseball and lacrosse (p \u3c 0.05). CONCLUSION: These findings suggest absolute HGS varies across different male sport athletes, therefore, normative values for HGS should be sport specific. Future research that explores the relationship between HGS and injury risk is recommended to assess the utility of using HGS to monitor fatigue and injury risk in athletes, especially those where grasping and grip is inherent to the sport-related tasks. Furthermore, this study focused exclusively on male Division I athletes, which may limit the generalizability of the findings to female athletes or those in different divisions or levels of competition

DSC MRI in the human brain using deoxyhemoglobin and gadolinium—Simulations and validations at 3T

IntroductionDynamic susceptibility contrast (DSC) MRI allows clinicians to determine perfusion parameters in the brain, such as cerebral blood flow, cerebral blood volume, and mean transit time. To enable quantification, susceptibility changes can be induced using gadolinium (Gd) or deoxyhemoglobin (dOHb), the latter just recently introduced as a contrast agent in DSC. Previous investigations found that experimental parameters and analysis choices, such as the susceptibility amplitude and partial volume, affect perfusion quantification. However, the accuracy and precision of DSC MRI has not been systematically investigated, particularly in the lower susceptibility range.MethodsIn this study, we compared perfusion values determined using Gd with values determined using a contrast agent with a lower susceptibility—dOHb—under different physiological conditions, such as varying the baseline blood oxygenation and/or magnitude of hypoxic bolus, by utilizing numerical simulations and conducting experiments on healthy subjects at 3T. The simulation framework we developed for DSC incorporates MRI signal contributions from intravascular and extravascular proton spins in arterial, venous, and cerebral tissue voxels. This framework allowed us to model the MRI signal in response to both Gd and dOHb.Results and discussionWe found, both in the experimental results and simulations, that a reduced intravascular volume of the selected arterial voxel, reduced baseline oxygen saturation, greater susceptibility of applied contrast agent (Gd vs. dOHb), and/or larger magnitude of applied hypoxic bolus reduces the overestimation and increases precision of cerebral blood volume and flow. As well, we found that normalizing tissue to venous rather than arterial signal increases the accuracy of perfusion quantification across experimental paradigms. Furthermore, we found that shortening the bolus duration increases the accuracy and reduces the calculated values of mean transit time. In summary, we experimentally uncovered an array of perfusion quantification dependencies, which agreed with the simulation framework predictions, using a wider range of susceptibility values than previously investigated. We argue for caution when comparing absolute and relative perfusion values within and across subjects obtained from a standard DSC MRI analysis, particularly when employing different experimental paradigms and contrast agents

Spinal Cord Segmentation by One Dimensional Normalized Template Matching: A Novel, Quantitative Technique to Analyze Advanced Magnetic Resonance Imaging Data

Spinal cord segmentation is a developing area of research intended to aid the processing and interpretation of advanced magnetic resonance imaging (MRI). For example, high resolution three-dimensional volumes can be segmented to provide a measurement of spinal cord atrophy. Spinal cord segmentation is difficult due to the variety of MRI contrasts and the variation in human anatomy. In this study we propose a new method of spinal cord segmentation based on one-dimensional template matching and provide several metrics that can be used to compare with other segmentation methods. A set of ground-truth data from 10 subjects was manually-segmented by two different raters. These ground truth data formed the basis of the segmentation algorithm. A user was required to manually initialize the spinal cord center-line on new images, taking less than one minute. Template matching was used to segment the new cord and a refined center line was calculated based on multiple centroids within the segmentation. Arc distances down the spinal cord and cross-sectional areas were calculated. Inter-rater validation was performed by comparing two manual raters (n = 10). Semi-automatic validation was performed by comparing the two manual raters to the semi-automatic method (n = 10). Comparing the semi-automatic method to one of the raters yielded a Dice coefficient of 0.91 +/- 0.02 for ten subjects, a mean distance between spinal cord center lines of 0.32 +/- 0.08 mm, and a Hausdorff distance of 1.82 +/- 0.33 mm. The absolute variation in cross-sectional area was comparable for the semi-automatic method versus manual segmentation when compared to inter-rater manual segmentation. The results demonstrate that this novel segmentation method performs as well as a manual rater for most segmentation metrics. It offers a new approach to study spinal cord disease and to quantitatively track changes within the spinal cord in an individual case and across cohorts of subjects

Resilience and positive feedbacks: Water quality management and eelgrass health in Great Bay Estuary, NH/ME Technical Report

This comprehensive technical report outlines the project’s motivations, context, methods, results, and discussion of results in the context of local management concerns. It provides evidence-based recommendations for decision makers in the region looking to better understand water quality, light, and eelgrass relationships

Resilience and positive feedbacks: Water quality management and eelgrass health in Great Bay Estuary, NH/ME “So What” Report

This report provides a high-level summary of the project and its implications. With a focus on lessons learned, the report distills why and how the project\u27s results are important for future eelgrass management. Geared toward broader audiences, this report can be used for public education and engagement with eelgrass management

Heterogeneous motor BOLD-fMRI responses in brain areas exhibiting negative BOLD cerebrovascular reactivity indicate that steal phenomenon does not always result from exhausted cerebrovascular reserve capacity

Introduction: Brain areas exhibiting negative blood oxygenation-level dependent cerebrovascular reactivity (BOLD-CVR) responses to carbon dioxide (CO2) are thought to suffer from a completely exhausted autoregulatory cerebrovascular reserve capacity and exhibit vascular steal phenomenon. If this assumption is correct, the presence of vascular steal phenomenon should subsequently result in an equal negative fMRI signal response during a motor-task based BOLD-fMRI study (increase in metabolism without an increase in cerebral blood flow due to exhausted reserve capacity) in otherwise functional brain tissue. To investigate this premise, the aim of this study was to further investigate motor-task based BOLD-fMRI signal responses in brain areas exhibiting negative BOLD-CVR. Material and methods: Seventy-one datasets of patients with cerebrovascular steno-occlusive disease without motor defects, who underwent a CO2-calibrated motor task-based BOLD-fMRI study with a fingertapping paradigm and a subsequent BOLD-CVR study with a precisely controlled CO2-challenge during the same MRI examination, were included. We compared BOLD-fMRI signal responses in the bilateral pre- and postcentral gyri - i.e. Region of Interest (ROI) with the corresponding BOLD-CVR in this ROI. The ROI was determined using a second level group analysis of the BOLD-fMRI task study of 42 healthy individuals undergoing the same study protocol. Results: An overall decrease in BOLD-CVR was associated with a decrease in BOLD-fMRI signal response within the ROI. For patients exhibiting negative BOLD-CVR, we found both positive and negative motor-task based BOLD-fMRI signal responses. Conclusion: We show that the presence of negative BOLD-CVR responses to CO2 is associated with heterogeneous motor task-based BOLD-fMRI signal responses, where some patients show -more presumed- negative BOLD-fMRI signal responses, while other patient showed positive BOLD-fMRI signal responses. This finding may indicate that the autoregulatory vasodilatory reserve capacity does not always need to be completely exhausted for vascular steal phenomenon to occur

Hemodynamic Failure Staging With Blood Oxygenation Level-Dependent Cerebrovascular Reactivity and Acetazolamide-Challenged (15^{15}O-)H2_{2}O-Positron Emission Tomography Across Individual Cerebrovascular Territories

BACKGROUND Staging of hemodynamic failure (HF) in symptomatic patients with cerebrovascular steno-occlusive disease is required to assess the risk of ischemic stroke. Since the gold standard positron emission tomography-based perfusion reserve is unsuitable as a routine clinical imaging tool, blood oxygenation level-dependent cerebrovascular reactivity (BOLD-CVR) with CO$_{2}$ is a promising surrogate imaging approach. We investigated the accuracy of standardized BOLD-CVR to classify the extent of HF. METHODS AND RESULTS Patients with symptomatic unilateral cerebrovascular steno-occlusive disease, who underwent both an acetazolamide challenge ($^{15}$O-)H$_{2}$O-positron emission tomography and BOLD-CVR examination, were included. HF staging of vascular territories was assessed using qualitative inspection of the positron emission tomography perfusion reserve images. The optimum BOLD-CVR cutoff points between HF stages 0-1-2 were determined by comparing the quantitative BOLD-CVR data to the qualitative ($^{15}$O-)H$_{2}$O-positron emission tomography classification using the 3-dimensional accuracy index to the randomly assigned training and test data sets with the following determination of a single cutoff for clinical application. In the 2-case scenario, classifying data points as HF 0 or 1-2 and HF 0-1 or 2, BOLD-CVR showed an accuracy of >0.7 for all vascular territories for HF 1 and HF 2 cutoff points. In particular, the middle cerebral artery territory had an accuracy of 0.79 for HF 1 and 0.83 for HF 2, whereas the anterior cerebral artery had an accuracy of 0.78 for HF 1 and 0.82 for HF 2. CONCLUSIONS Standardized and clinically accessible BOLD-CVR examinations harbor sufficient data to provide specific cerebrovascular reactivity cutoff points for HF staging across individual vascular territories in symptomatic patients with unilateral cerebrovascular steno-occlusive disease