Articles Signifying Renogram Processing Practices-A Systematic Review

The renography represents time activity process detected when one measures the activity in the kidneys after the dose injection of radiolabeled radio tracer(e.g.99mTc- DTPA,99mTc-MAG3). Interpretation of this renal scan helps to diagnose whether the drainage function from the kidney is normal or abnormal. This renal tracer’s data is processed by mathematical models and data processing techniques like Rutland-Patlak and deconvolution methods to produce renograph. This research study is carried out to review previously published research articles incorporating various methods, their applications and image processing algorithms as well as techniques that were applied to process renal radiotracer’s transit time data. This review includes various types, advantages, gaps and possible scopes for existing renogram data processing techniques. After analysis process of 142 articles it is found that, maximum of the articles are associated with renal scan’s processing methods that are limited to renal patient’s related disease categories and having absence of quantifiable measurement and study of parenchymal radio tracer’s transit time counted from renal cortex to renal pelvis path while limited numbers of articles are purely related to applied algorithms for detecting obstruction level qualitatively.

Rainfall Investigation by Means of Marine In Situ Gamma-ray Spectrometry in Ligurian Sea, Mediterranean Sea, Italy

Marine in situ gamma-ray spectrometry was utilized for a rainfall study at the W1M3A observing system in Ligurian Sea, Mediterranean Sea, Italy. From 7 June to 10 October 2016, underwater total gamma-ray counting rate (TCR) and the activity concentration of radon daughters 214Pb, 214Bi and potassium 40K were continuously monitored along with ambient noise and meteorological parameters. TCR was proven as a good rainfall indicator as radon daughters’ fallout resulted in increased levels of marine radioactivity during and 2–3 h after the rainfall events. Cloud origin significantly affects TCR and radon progenies variations, as aerial mass trajectories, which extend upon terrestrial areas, result in higher increments. TCR and radon progenies concentrations revealed an increasing non-linear trend with rainfall height and intensity. 40K was proven to be an additional radio-tracer as its dilution was associated with rainfall height. 40K variations combined with 214Bi measurements can be used to investigate the mixing of rain- and seawater. In comparison with measurements in the atmosphere, the application of marine in situ gamma-ray spectrometry for precipitation investigation provided important advantages: allows quantitative measurement of the radionuclides; 40K can be used, along with radon daughters, as a radio-tracer; the mixing of rain- and seawater can be associated with meteorological parameters.

A case of peritoneal-pericardial leak in a 19-year-old patient on peritoneal dialysis

We report a case of a peritoneal-pericardial leak in peritoneal dialysis.A 19-year-old patient, with no history of heart disease, with unkown chronic kidney disease, treated with continuous ambulatory peritoneal dialysis (CAPD) for 10 months. complained of chest pain and tachycardia, revealing pericardial effusion of great abundance. Pericardial drainage was necessary. The fluid analysis was a transudate with glucose levels 5 times higher than glucose plasma levels. A peritoneal scintigraphy was performed and showed a distribution of the radio-tracer in the peritoneal cavity without any image of a leak. With clinical and especillay biological arguments, the patient was diagnosed with a peritoneal-pericardial leak.After pericardial drainage and temporary switch to hemodialysis, automated peritoneal dialysis was resumed with progressive increase in volumes, without recurrence of the leak after a 6 months follow-up.

A novel mathematical approach to estimate the hepatic, cerebral and renal blood flow from dynamic nuclear imaging studies independently of the used radio tracer

Background The blood flow (BF) is a critical determinant of organ functionality. Its assessment in the course of routine nuclear medicine examinations, including planar scintigraphy and positron emission tomography (PET), can be relevant for the diagnosis and monitoring of various conditions. The aim of this study was to investigate a new mathematical approach developed to estimate the organ BF from dynamic imaging data and to analyze if this method can be applied independent of the used radio tracer or imaging modality. The new approach uses the early phase of time activity curves extracted from animal and human dynamic scintigraphy and PET scans. Independence of tracer characteristics was evaluated with major oxygen-dependent organs (kidneys, liver, brain) of a mouse model. The approach was also applied on renal scans with two different imaging modalities from a representative cohort of 32 human subjects and compared to reference values. Results The mean organ-specific BF determined in the mouse model revealed no significant differences between the administered radiotracers and all calculated values corresponded to normal values (kidneys: 1.0-1.1 ml/min, liver: 1.4–1.6 ml/min, brain: 0.2 ml/min). In the human study cohort, the renal BFs from the two performed imaging modalities showed a good correlation (r = 0.61, p = 0.001) and a small significant difference (p = 0.047) among each other and good correlations to the reference value obtained from blood sampling (r = 0.79 and r = 0.52). Conclusions A mathematical approach was developed to assess the organ BF solely from dynamic imaging scans without the necessity of additional measurements. Preliminary data suggests that several radiotracers might be feasible to estimate the BF in major oxygen-dependent organs.

Quorum sensing and iron regulate a two-for-one siderophore gene cluster inVibrio harveyi

The secretion of small Fe-binding molecules called siderophores is an important microbial strategy for survival in Fe-limited environments. Siderophore production is often regulated by quorum sensing (QS), a microbial counting technique that allows organisms to alter gene expression based on cell density. However, the identity and quantities of siderophores produced under QS regulation are rarely studied in the context of their roles in Fe uptake. We investigated the link between QS, siderophores, and Fe uptake in the model marine organismVibrio harveyiwhere QS is thought to repress siderophore production. We find thatV. harveyiuses a single QS- and Fe-repressed gene cluster to produce both cell-associated siderophores (amphiphilic enterobactins) as well as several related soluble siderophores, which we identify and quantify using liquid chromatography-coupled (LC)-MS as well as tandem high-resolution MS (LC-HR-MS/MS). Measurements of siderophore production show that soluble siderophores are present at ∼100× higher concentrations than amphi-enterobactin and that over the course of growthV. harveyidecreases amphi-enterobactin concentrations but accumulates soluble siderophores.55Fe radio-tracer uptake experiments demonstrate that these soluble siderophores play a significant role in Fe uptake and that the QS-dictated concentrations of soluble siderophores in stationary phase are near the limit of cellular uptake capacities. We propose that cell-associated and soluble siderophores are beneficial toV. harveyiin different environmental and growth contexts and that QS allowsV. harveyito exploit “knowledge” of its population size to avoid unnecessary siderophore production.

Manual Lymphatic Drainage after Subepidermal Tracer Injection Optimizes Results of Sentinel Lymph Node Labeling in Primary Breast Cancer

Introduction: Our aim was to assess the practicability and reliability of a novel labeling regime for axillary sentinel lymph nodes (SLNs) in early breast cancer. Methods: 362 patients with early breast cancer (bilateral in 9 cases, giving a total of 371 cases) underwent intradermal radio tracer injection with simultaneous manual lymphatic drainage. SLN biopsy was performed within 24 h. For retrospective analysis, data were extracted from patient's records. Results: At least 1 SLN was detected intraoperatively in 369 cases (99.5%, range 1-9 nodes). This node was metastatic in 88 and unaffected in 281 cases. Coincidentally removed but unlabeled lymph nodes were affected in 3 cases in which the SLN was unaffected (3/153 = 2%). In all cases, on histological evaluation, tissue removed as SLN contained lymph nodes. After a period of 69.5 months (median 1.7-115.8 months), no axillary recurrences were observed in 213 patients. Conclusion: Manual lymphatic drainage is a simple technique that leads to an extremely high pick-up rate of axillary SLNs after subepidermal radio tracer injection. If unaffected, this node correctly predicts nodal-negative disease in 98% of cases studied.