Isotope Injection Research Articles

Effects of soil heterogeneity and preferential flow on the water flow and isotope transport in an experimental hillslope

Soil water movement plays vital roles in hillslope runoff generation and groundwater and surface water interaction. However, there are still knowledge gaps about the impacts of soil heterogeneity and preferential flow on the internal water flow and transport process. In this study, the vertical soil heterogeneity focused on the variations in soil retention capacity, and the consideration of lateral preferential flow emphasized the higher hydraulic conductivity. We combined isotopic tracing and numerical modeling in an artificial hillslope, focusing on monitored processes of the artificial rainfall and isotopic tracing experiment. The results showed that the soil moisture quickly accumulated at the bottom of the hillslope during rainfall events, while the 2H enrichment occurred in the topsoil derived from enriched isotope injection in the second artificial rainfall. The evaporation process slowed down the mixing of new water in the topsoil and old water in the lower layer. We found that the vertical soil heterogeneity had significant influences on the internal water and isotope transport paths within the hillslope. The lateral preferential flow played an important role in the water flux and transport time to the seepage face. The coupling of isotopic tracing, which reflects the water transport and mixing with the hillslope, effectively improved the model simulation and mechanism analysis of hillslope water flow. Our findings provide new insights into the mechanisms governing soil water flow and transport dynamics in hillslopes, taking into account vertical soil heterogeneity and lateral preferential flow.

Remote ischemic peri-conditioning suppressed the activation of cardiac sympathetic nervous system in patients with acute myocardial infarction: a randomized controlled trial

Abstract Background The activation of cardiac sympathetic nervous system is associated with poor prognosis in patients with acute myocardial infarction (AMI). Remote ischemic peri-conditioning (RIPC) is reported to improve clinical outcome in patients with AMI. However, there is not fully clarified whether RIPC could have an effect on cardiac sympathetic activity. Purpose The purpose of this study is to investigate the effect of RIPC on cardiac sympathetic activity in patients with AMI. Methods We randomly assigned 157 patients with suspected AMI undergoing emergent percutaneous coronary intervention to receive transient limb ischemia (by inflating a cuff at 200 mmHg for 4×5 minutes: RIPC group, n=77) or no procedure (control group, n=80) upon arrival to the cardiac catheterization laboratory. After excluding inappropriate patients such as those who were diagnosed with other than AMI, we analyzed 122 patients (62 patients in RIPC and 60 in control group). The primary endpoint was cardiac sympathetic activity assessed by the cardiac MIBG imaging washout rate (WR) at discharge and 1 year after discharge. WR and late heart-to-mediastinum ratio (HMR) in cardiac MIBG was calculated from the chest anterior view images obtained at 20 and 200 min after isotope injection. Results Patients in RIPC and control group had similar demographic and clinical characteristics at baseline. There was no significant difference in WR between two groups at discharge. Although WR was significantly decreased 1 year after the discharge in both groups, patients in RIPC group showed significantly lower WR than those in control group (22.0 [15.1-30.6]% and 26.5 [18.4-34.4]%, p=0.0269) 1 year after the discharge. Late HMR significantly decreased during 1-year follow-up in patients only in RIPC group (p=0.0133) and patients in RIPC group tended to show higher late HMR compared to those in control group (2.01 [1.79-2.25] and 1.92 [1.72-2.11], p=0.0581) 1 year after the discharge. Conclusion(s) Remote ischemic peri-conditioning could suppress the augmented cardiac sympathetic activity in patients with acute myocardial infarction during 1-year follow-up.

Inhibition of keloid by 32P isotope radiotherapy through suppressing TGF-β/Smad signaling pathway.

Keloid seriously affects the appearance, and is accompanied by some symptoms including pain, burning, itching. Radioactive nuclides such as 32P have been proved to be effective in inhibiting the formation of keloid, but the mechanism remains unclear. The keloid animal model was established through keloid tissues implantation. Hematoxylin-Eosin (HE) and Masson staining were performed to investigate histological changes and collagen deposition. The mRNA and protein expression were assessed using RT-PCR and western blotting, respectively. Cell apoptosis and cycle were evaluated through flow cytometry. Both 32P isotope injection and skin path significantly reduced the size of keloid, and inhibited TGF-β/Smad signaling pathway. SRI-011381, the agonist of TGF-β/Smad signaling pathway, markedly reversed the influence of 32P isotope on cell proliferation, cell apoptosis, cell cycle of LNCaP cells and TGF-β/Smad signaling pathway. 32P isotope injection and skin path greatly reduced the size of keloid, and the TGF-β/Smad signaling pathway was remarkably inhibited by 32P isotope treatment. The regulation of dermal fibroblast by 32P isotope was reversed by SRI-011381. 32P isotope might inhibit keloid through suppressing TGF-β/Smad signaling pathway. Our study provides a novel therapeutic strategy for the treatment of keloid.

Gut-derived β-amyloid: Likely a centerpiece of the gut–brain axis contributing to Alzheimer’s pathogenesis

ABSTRACT Peripheral β-amyloid (Aβ), including those contained in the gut, may contribute to the formation of Aβ plaques in the brain, and gut microbiota appears to exert an impact on Alzheimer’s disease (AD) via the gut-brain axis, although detailed mechanisms are not clearly defined. The current study focused on uncovering the potential interactions among gut-derived Aβ in aging, gut microbiota, and AD pathogenesis. To achieve this goal, the expression levels of Aβ and several key proteins involved in Aβ metabolism were initially assessed in mouse gut, with key results confirmed in human tissue. The results demonstrated that a high level of Aβ was detected throughout the gut in both mice and human, and gut Aβ42 increased with age in wild type and mutant amyloid precursor protein/presenilin 1 (APP/PS1) mice. Next, the gut microbiome of mice was characterized by 16S rRNA sequencing, and we found the gut microbiome altered significantly in aged APP/PS1 mice and fecal microbiota transplantation (FMT) of aged APP/PS1 mice increased gut BACE1 and Aβ42 levels. Intra-intestinal injection of isotope or fluorescence labeled Aβ combined with vagotomy was also performed to investigate the transmission of Aβ from gut to brain. The data showed that, in aged mice, the gut Aβ42 was transported to the brain mainly via blood rather than the vagal nerve. Furthermore, FMT of APP/PS1 mice induced neuroinflammation, a phenotype that mimics early AD pathology. Taken together, this study suggests that the gut is likely a critical source of Aβ in the brain, and gut microbiota can further upregulate gut Aβ production, thereby potentially contributing to AD pathogenesis.

Effect of Gallium-68 isotope injection on hemoglobin derivatives concentrations after instant injection and its recovery in male rabbits (Oryctolagus cuniculus)

Oxidizing effects of ionizing radiation are well established and almost understood. However, exposure to low doses of widely used isotopes may result in minor and hidden oxidative stress in some forms of hemoglobin. This formation alteration regarding the legends of hemoglobin's stereochemical function may play a role in hemoglobin dysfunction. There are limited studies related to the effect of gallium isotope injections. The study intends to find the effect of gallium-68 isotope injection on male rabbits. It was conducted on thirty-two male rabbits (Orycytolagus cuniculus) divided into Group I: control and Group II: animals exposed to gallium-68 isotope at a similar dose commonly used in diagnostic protocols for humans. Blood samples were collected twice: the first was after two hours of injection with isotopes and the second was after twelve hours of injection. A linear, four-mathematical-equations matrix based on the Lamber-Beer law was used to measure the concentration of different hemoglobin derivatives. Results revealed a significant elevation (P<0.05) of methemoglobin, the oxidized form of hemoglobin, two hours after injection (Total hemoglobin = 4.463 ± 0.83), but this effect was completely reversed after twelve hours. This concluded that even low doses of isotopes result in oxidation of hemoglobin that recovers shortly. Furthermore, the outcome of the study supports the healthcare centres to understand the effect of gallium-68 injections on animals.

Giant Cell Tumor of Bone Versus Tenosynovial Giant Cell Tumor - Similarities and Differences.

Giant cell tumor of bone (GCTB) and tenosynovial giant cell tumor (TGCT) share misleadingly similar names, soft texture and brown color macroscopically, osteoclast-like multinucleated giant cells microscopically and localisation in the musculoskeletal system. However, these two tumor types are biologically and clinically two distinct entities with different natural courses of progression and considerably different modes of surgical and medical treatment. In this article, we provide a detailed update on the similarities and the differences between both tumor types.GCTB is a locally aggressive osteolytic bone tumor, commonly seen in patients in their third decade of life. It usually occurs as a solitary lesion in the meta-epiphyseal region of long bones. It can be diagnosed using plain radiographic imaging, CT radiography or MRI to estimate the tumor extent, soft tissue and joint involvement. GCTB is usually treated with intralesional excision by curettage. Systemically, it can be treated with bisphosphonates and denosumab or radiotherapy.TGCT is a rare, slowly progressing tumor of synovial tissue, affecting the joint, tendon sheath or bursa, mostly seen in middle-aged patients. TGCT is usually not visible on radiographs and MRI is mostly used to enable assessment of potential bone involvement and distinguishing between two TGCT types. Localised TGCT is mostly treated with marginal surgical resection, while diffuse TGCT is optimally treated with total synovectomy and is more difficult to remove. Additionally, radiotherapy, intraarticular injection of radioactive isotopes, anti-TNF-α antibodies and targeted medications may be used.

Preoperative Axillary Ultrasound-guided Wire Localization and Lymphoscintigraphy for Sentinel Lymph Node Biopsy in Breast Cancer Patients

Background: Breast cancer has the highest incidence and mortality among female malignant tumors. Breast cancer with negative axillary lymph nodes has been diag- nosed mainly at an early stage. Sentinel lymph node biopsy (SLNB) is a standard screening technique for patients with early-stage breast cancer and clinically nega- tive lymph nodes. Lymphoscintigraphy (sentinel lymph node mapping) has been reg- ularly used as the standard method for SLNB. Today, ultrasound-guided wire locali- zation (USGWL) is a well-established technique with superior outcomes. Therefore, we attempted to determine whether preoperative UGWL and lymphoscintigraphy (blue dye and isotope injection) improve SLN detection and false-negative rate in breast cancer patients undergoing SLNB and identify clinical factors that may affect the diagnostic accuracy of axillary ultrasound (AUS). Methods: Between December 2018 and June 2019, 55 patients with clinical T1- 3N0 breast cancer eligible for an SLNB at Imam Khomeini Hospital in Tehran were included in our study. Tumor characteristics and demographic data were collect- ed by reviewing medical records and questionnaires prepared by our surgical team. The day before SLNB, all patients underwent ultrasound-guided wire localization of SLN. Lymphoscintigraphy was performed with an unfiltered 99mTc-labelled sulfur colloid peritumoral injection followed by methylene blue dye injection. The results were analyzed based on the permanent pathology report. Results: Among the 55 patients, 71.8% of SLNs were detected by wire localization, while 57.8% were found by methylene blue mapping and 59.6% by gamma probe detection. Compared with wire localization and isotope injection, the methylene blue dye technique had a low sensitivity (72.2%), while both wire localization and isotope injection reached 77.8%. The sensitivity, specificity, and accuracy of UGWL were 77.8%, 42.1%, and 65.4%, respectively. Otherwise, methylene blue dye and isotope injection accuracy was 47.3% and 50.1%, respectively. Furthermore, there was a significant relationship between BMI, tumor size, laterality, reactive ALN, and the accuracy of preoperative AUS. But there was no significant correlation between age, weight, height, tumor biopsy, tumor location, the time interval between methylene blue dye and isotope injection to surgery, and also the type of surgery to the accuracy of preoperative AUS. Conclusion: Preoperative UGWL can effectively identify SLNs compared to lym- phoscintigraphy (blue dye and isotope injection) in early breast cancer patients un- dergoing SLNB.

Abstract 10510: Prognostic Value of the Combination of Cardiac MIBG Imaging and Serum Cholinesterase Level in Patients Admitted for Acute Decompensated Heart Failure

Backgrounds: Cardiac MIBG imaging provides prognostic information in patients with acute decompensated heart failure (ADHF). On the other hand, serum cholinesterase (CHE) level, which reflect various factors such as hepatic function, inflammation and nutritional status, has been reported to be associated with poor outcome in ADHF patients. However, there is no information available on the prognostic value of the combination of cardiac MIBG imaging and CHE level in patients admitted for ADHF. Methods: We studied 579 consecutive patients admitted for ADHF. Cardiac MIBG imaging, echocardiography and venous blood sampling were performed just before discharge. The cardiac MIBG heart-to-mediastinum ratio (late HMR) was measured on the chest anterior view images obtained at 200 min after the isotope injection. The primary endpoint was cardiac event (CE) defined as unplanned heart failure hospitalization and cardiac death. Results: During a follow up period of 2.8±0.9 years, 196 patients reached the primary endpoint. On multivariate Cox analysis, late-HMR (p<0.0001, HR 1.82 [1.34-2.47) and serum CHE level (p=0.047, HR 1.40 [1.01-1.94]) were significantly associated with CE after adjustment for age, sex, left ventricular ejection fraction, history of hypertension, diabetes mellitus, hemoglobin, blood urea nitrogen and albumin. Kaplan-Meier survival curve analysis demonstrated that patients with both low serum CHE level (<217 U/L=median value) and late-HMR (<1.66=median value) had a significantly increased risk of CE in than those either or none of them. Conclusion: The combination of cardiac MIBG imaging and serum CHE level would be useful for stratifying ADHF patients at risk for cardiac events.

Sentinel lymph node mapping with patent blue dye in patients with breast cancer: a retrospective single institution study.

Since the end of the last century, sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) as standard of care for axillary staging in early breast cancer in patients without any clinical sign of axillary lymph node infiltration. The worldwide most frequently used mapping method consists in the injection of radioactive technetium-99 isotope alone or in combination with blue dye. As a specific infrastructure and dedicated personnel are needed for the use of a radioactive tracer, the CHC in Liege (Belgium) decided to test the use of patent blue dye alone to detect sentinel lymph nodes in a large consecutive cohort of patients and compared the results with radioactive mapping methods and guidelines recommendations. Patent blue dye was used in 456 consecutive patients with early breast cancer who underwent conservative breast cancer surgery or radical mastectomy between 1/1/2000 and 31/12/2007 in a community hospital (CHC Liège, Belgium). After SLNB, an ALND was performed in each patient. Sentinel lymph nodes were identified in 444 patients among the 456 patients evaluated by this mapping method during this time period, which represents a detection rate of 97.4%. Infiltrated lymph nodes were detected in 32.7% of patients (149/456) while in the 444 patients with sentinel lymph nodes identified and resected, 137 patients have at last one positive lymph node (30.9%). The false negative rate was 4.9% and the predictive negative value was 97.7% with the blue dye mapping method. In addition of the simplicity of the method and the large economic advantage, SNLB using blue dye alone showed a quite acceptable performance in our retrospective analysis concerning its ability to find the SLN as well as its reliability to remove the good ones.

The use of radiosynovectomy in patients with juvenile idiopathic arthritis. Assessment of treatment efficacy and safety.

ObjectivesThe aim of the study was to evaluate the usefulness of knee joint radiosynovectomy (RS) in patients suffering from juvenile idiopathic arthritis (JIA).Material and methodsOne hundred RS procedures performed in 58 patients with JIA in average age 10.4 years were evaluated.ResultsAfter 6 weeks, a decrease in the number of cases with joint pain from 90.3% to 29%, with joint oedema from 100% to 74.5%, with joint exudate from 100% to 60.6%, with gait disorders from 19.4% to 3.2%, with joint mobility disorders from 51.1% to 26.6% in the RS cases was observed. A reduction of the score in the Colorado scale from 10.9 to 4.66, in the pain visual analogue scale (VAS) from 50 to 10, in the illness VAS assessed by the patient/parent from 69.9 to 32.4, in the illness VAS assessed by the physician from 68.8 to 36.9 was observed. Six months after the RS procedure, a reduction in the number of cases with joint pain from 89.5% prior to the procedure to 29.5%, with oedema from 100% to 58.3%, with exudate from 100% to 46.9%, with gait disorders from 20% to 2.1%, with joint motility disorders from 51.1% to 26.1% was achieved. The score in the Colorado scale was reduced from 10.9 to 4.04, in the pain VAS from 40 to 0, in the illness VAS assessed by the patient/parent from 69.7 to 27.9, in the illness VAS assessed by the physician from 68.8 to 32.4. In ultrasound examinations, the greatest improvement compared to the initial condition was recorded in the 6th month after the RS. Radiosynovectomy was positively evaluated by parents and patients in 34 anonymous surveys. Early and late observations (average 1473 days) did not show lesions at the isotope injection site, and no neoplastic lesions were observed.ConclusionsRadiosynovectomy is a valuable therapeutic option for local treatment in patients with JIA.

Intermittent Leucine Pulses Enhance Skeletal Muscle mTOR Signaling and Protein Synthesis in Continuously Fed Preterm Pigs

Abstract Objectives Extrauterine growth restriction in premature infants is associated with reduced lean mass and long-term morbidities. We have reported previously that intermittent parenteral pulses of Leu promote skeletal muscle mTOR signaling and protein synthesis of continuously fed neonatal pigs born at term. The objective of this study was to determine the effect of prematurity on the response of skeletal muscle anabolic pathways to intermittent parenteral Leu pulses in continuously fed pigs. Methods Pigs delivered 10 d preterm by C-section were fitted with jugular vein and carotid artery catheters and an orogastric feeding tube. Pigs were advanced from parenteral to enteral feeding over 4 d (195 kcal · kg−1 · d−1; 13.5 g protein · kg−1 · d−1). On day 4, pigs were assigned to 1 of 4 treatments: 1) ALA (continuous feeding, 7.5 mL · kg−1 · h−1; 800 μmol Ala · kg−1 · h−1 every 4 h; n = 7); 2) L1 × (continuous feeding; 800 μmol Leu · kg−1 · h−1 every 4 h; n = 6); 3) L2 × (continuous feeding; 1600 μmol Leu · kg−1 · h−1 every 4 h; n = 6); and 4) INT (intermittent feeding; 30 mL · kg−1 fed over 15 min every 4 h; n = 5). On day 5, pigs received L-[ring-2H5]-Phe 30 min after starting the pulse (groups 1, 2, and 3) or meal feeding (group 4). Pigs were euthanized 30 min after isotope injection and longissimus dorsi muscle was collected. Protein synthesis was determined by LC/MS-MS. Indices of amino acid signaling and mTOR activation were determined by immunoprecipitation and immunoblot assays. Results Skeletal muscle protein synthesis was higher in L2 × (+37%) and INT (+31%) compared to ALA (P < 0.05), but was not different between L2 × and INT; protein synthesis in L1 × was intermediate and not different from all other groups. The phosphorylation of 4EBP1, downstream of mTOR, was higher in L2 × and INT compared to ALA (P < 0.05), whereas 4EBP1 phosphorylation in L1 × was lower compared to INT (P < 0.05) but not different compared to ALA and L2 × . The abundance of mTOR · RagA complex, upstream of mTOR and activated in response to Leu, was higher in L2 × and INT compared to ALA and L1 × (P < 0.05). Conclusions These results show that parenteral Leu can enhance anabolic signaling and protein synthesis in skeletal muscle during continuous feeding in preterm pigs, but the dose required is higher than in pigs born at term. Funding Sources Research was supported by NIH and USDA.

Novel nanotech antioxidant cocktail prevents medical diagnostic procedures ionizing radiation effects

Ionizing radiation (IR) exposure results in oxidative damage causing cytotoxic and genotoxic effects. Double-strand breaks (DSBs) are considered the most significant DNA lesions induced by ionizing radiation. The present study evaluates the radio protective effect of a novel antioxidant cocktail through quantification of DSB in peripheral blood lymphocytes (PBL) in vivo. The study included 16 consecutive patients who were divided into 2 groups, 6 patients received the novel antioxidant cocktail and 10 control patients. Blood samples were drawn from the patients undergoing bone scan, before the injection of the 99mTc MDP tracer and 2 h after the injection. Quantification of the IR damage was done by Immunofluorescence analysis of the phosphorylated histone, γ-H2AX, used to monitor DSB induction and repair in PBL. The radiation effect of the control group was measured by 2 variables, the average DBSs foci per nucleus and the percent of the DSB bearing cells in PBL. The findings showed a significant increase in the DSBs after isotope injection with an average increment of 0.29 ± 0.13 of foci/nucleus and 17.07% ± 7.68 more DSB bearing cells (p < 0.05). The cocktail treated group showed a lower difference average of − 2.79% ± 6.13 DSB bearing cells. A paired t-test revealed a significant difference between the groups (p < 0.005) confirming the cocktail’s protective effect. The novel anti-oxidant treatment decreases the oxidative stress-induced DNA damage and can be considered as a preventative treatment before radiation exposure.

Abstract PS1-62: Two decades of experience with sentinel node staging of axilla - is false negative no longer a worry?

Abstract Aim: To review current literature and standard practices in various techniques of sentinel node biopsy for staging the axilla for treating early breast cancer. The purpose is to provide evidence based recommendation as guidance platform for optimal true sentinel node retrieval irrespective of surgeon expertise. Background: Axillary conservation is the way forward after game changing trials like ACOSOG Z0011, surrogate trials like IBCSG,AMAROS, ALMANAC, ongoing POSNOC, and newbie ATNEC have progressively or plan to decrease the need to unnecessarily fiddle with the axilla thereby increasing the chances of arm related and other morbidities. Axillary sentinel node biopsy entails retrieval of first draining lymph node in the breast-axilla pathway to plan treatment in breast cancer by appropriate staging of axilla. Current standard is the utilisation of double agent technique with radioactive isotope and blue dye injection to decrease false negative rates for true sentinel node retrieval. Novel techniques like magnetic and infrared tracing are still being investigated for validation. Method: PMC, Medline, EMBASE, PubMed and Cochrane library searched for clinical trials, randomised trials, systematic reviews and meta-analysis on techniques of axillary sentinel node biopsy in early breast cancer. This covered the last 25 years literature on the topic. Results: The search yielded 197 publications which were subjected to a meticulous review and narrowed to a select pertinent body of evidence to extrapolate suggested guidance rationally, the bibliography of which is provided at the end. Conclusion: Single agent preferably radioisotope for lymphatic mapping is recommended in palpable and good biology tumours. Use of single agent blue dye can be standardised in axillary tail tumours. It is also recommended as being effective when isotope mapping is logistically not feasible or during pandemics like COVID 19 where looming infrastructure challenges are prevalent. Dual agent technique should be considered in previously treated breast and axilla, neoadjuvant chemotherapy cohort, bad tumour biology, high BMI and macromastia groups for true nodal retrieval. Optimal number of nodes taken out should not be more than three (n=3). Lower axillary sampling of not more than 3 nodes is recommended for troubleshooting with any localising agent technique. Triple site injection at peri-tumoural, subcutaneous and sub areolar regions and larger volume of blue dye agent injection of up to 8mls increases the localisation success in the dual technique group for lymphatic mapping. Magnetic tracing can be used as an adjunct to either single agent radioactive isotope or blue dye (RI/BD) technique when there is failure to localise the sentinel node. Citation Format: Tahera Arif, Mohammed Shamim Absar. Two decades of experience with sentinel node staging of axilla - is false negative no longer a worry? [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-62.

Effect of automatic injectors on the injection latency, safety, and seizure onset zone localization of ictal single photon emission computed tomography studies in adult epilepsy monitoring unit

BackgroundIctal Single Photon Emission Computed Tomography (iSPECT) is one of the established tools utilized in the presurgical evaluation of patients with drug-resistant epilepsy (DRE). Timely isotope injection for an iSPECT is critical for optimal yield but poses logistical challenges when done manually. We aim to evaluate the added value of automatic iSPECT injectors (ASIs) in overcoming such challenges. MethodsWe retrospectively reviewed all cases admitted to the University of Pittsburgh Medical Center (UPMC) Epilepsy Monitoring Unit from Jan 1, 2010, through Dec 31, 2016, who underwent an iSPECT. We compared the manually injected iSPECTs with those performed with ASIs. ResultsA total of 123 iSPECTs were reviewed. The manually injected iSPECT group consisted of 35 patients (median age, 35 years; and 19 males). The automatically injected iSPECT group consisted of 88 patients (median age, 36 years; and 46 males). The two groups were comparable in age, gender, epilepsy treatment, focal features on neuropsychological testing (NPT), EEG, and MRI, and temporal origin of seizures (p > 0.05).Compared to manually injected iSPECTs, automatically injected ISPECTs’ median injection latency (IL) was shorter (18.5 vs. 60 s, p < 0.001); the ratio of IL/total duration of seizure was lower (0.395 vs. 0.677, p < 0.001); postictal injections were less frequent (4 (4.5 %) vs. 7 (20 %), p = 0.007); the number of isotope spills was less (zero vs. 3, p = 0.022); and successfully localizing iSPECTs were more prevalent (81.8 % vs. 62.9 %, p = 0.025), even after adjusting for focal features on NPT, EEG, and MRI, the temporal origin of seizures, and seizure duration (OR of 5.539, 95 %CI = 1.653–18.563, p = 0.006). ConclusionsUtilization of ASIs leads to a significant shortening of iSPECT IL with less postictal injections, provides a safer injection option for the EMU staff, and leads to a significant improvement in the number of successfully localizing iSPECTs.

Identification isotopique du ganglion sentinelle : comparaison du SNOLL avec la technique isotopique de référence

IntroductionAxillary staging remains the most accurate predictive factor for recurrence risk and survival in patients with invasive breast carcinoma. Sentinel Node Occult Lesion Localization (SNOLL) allows with a single intra-lesion injection both localization of impalpable breast lesion and sentinel node biopsy. Our aim was to compare the efficacy of SNOLL and standard radio isotopic method for sentinel node localization by lymphoscintigraphy. MethodsThis retrospective study enrolled 100 patients treated for breast carcinoma with indication of sentinel node biopsy between may 2017 and January 2019 in breast surgery unit of Montpellier university hospital. ResultsSNOLL and standard radio isotopic method were realized in respectively 65 and 35 patients. Failure rates of sentinel node localization were respectively 34% and 11% by lymphoscintigraphy (P=0.02), 17% and 9% intraoperatively and 11% et 6% using radioisotope combined with colorimetric method. DiscussionFailure rate of sentinel node localization is higher using SNOLL. This rate is reduced by additional radioisope migration in the time between isotope injection and surgery and by the use of combined method. SNOLL should therefore be combined with colorimetric method. These results must be confirmed in a larger study.

Validation of saliva and urine use and sampling time on the doubly labelled water method to measure energy expenditure, body composition and water turnover in male and female cats.

Less invasive protocols are necessary to study energy expenditure (EE) of cats living in homes for expressing their normal living conditions. The present study compared sampling times and the use of saliva, urine and blood to measure 2H and 18O to apply the doubly labelled water method. In the first study, four cats were used to evaluate the enrichment (2, 4, 6, 7 and 8 h) and elimination (2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 d) of 2H and 18O (subcutaneously injected). The maximum enrichment was after 5 h (R2 0·82) of injection, with an Ln linear elimination of both isotopes (P < 0·001; R2 0·99). The results of EE were similar, regardless of the sampling time used (P = 0·999). In the second study, seven male cats and seven female cats were used. Before and after isotope injection (5 h, 7 d, 10 d and 14 d), blood, saliva and urine were collected. Isotope enrichment was lower in urine (P < 0·05) and at the similar level in blood and saliva. Isotope elimination was similar for all fluids (P < 0·473). The EE calculated with blood and saliva was similar but higher for urine (P = 0·015). According to Bland-Altman statistics, blood and saliva presented low bias and high correlation (P < 0·001), but this was not observed for urine (P = 0·096). Higher EE was observed for male cats (384 (se 39) kJ/kg0·67 per d) than for female cats (337 (se 34) kJ/kg0·67 per d; P < 0·05). The sampling time for the method is flexible, and saliva can be used as a substitute for blood.

Prognostic significance of cardiac I-123-metaiodobenzylguanidine imaging in patients with reduced, mid-range, and preserved left ventricular ejection fraction admitted for acute decompensated heart failure: a prospective study in Osaka Prefectural Acute Heart Failure Registry (OPAR).

Cardiac 123I-metaiodobenzylguanidine (123I-MIBG) imaging provides prognostic information in patients with chronic heart failure (HF). However, there is little information available on the prognostic role of cardiac 123I-MIBG imaging in patients admitted for acute decompensated heart failure (ADHF), especially relating to reduced ejection fraction [HFrEF; left ventricular ejection fraction (LVEF) < 40%], mid-range ejection fraction (HFmrEF; 40% ≤ LVEF < 50%) and preserved ejection fraction (HFpEF; LVEF ≥ 50%). We studied 349 patients admitted for ADHF and discharged with survival. Cardiac 123I-MIBG imaging, echocardiography, and venous blood sampling were performed just before discharge. The cardiac 123I-MIBG heart-to-mediastinum ratio (late H/M) was measured on the chest anterior view images obtained at 200 min after the isotope injection. The endpoint was cardiac events defined as unplanned HF hospitalization and cardiac death. During a follow-up period of 2.1 ± 1.4 years, 128 patients had cardiac events (45/127 in HFrEF, 28/78 in HFmrEF, and 55/144 in HFpEF). On multivariable Cox analysis, late H/M was significantly associated with cardiac events in overall cohort (P = 0.0038), and in subgroup analysis of each LVEF subgroup (P = 0.0235 in HFrEF, P = 0.0119 in HFmEF and P = 0.0311 in HFpEF). Kaplan-Meier analysis showed that patients with low late H/M (defined by median) had significantly greater risk of cardiac events in overall cohort (49% vs. 25% P < 0.0001) and in each LVEF subgroup (HFrEF: 48% vs. 23% P = 0.0061, HFmrEF: 51% vs. 21% P = 0.0068 and HFpEF: 50% vs. 26% P = 0.0026). Cardiac sympathetic nerve dysfunction was associated with poor outcome in ADHF patients irrespective of HFrEF, HFmrEF, or HFpEF.

P762Usefulness of 2-year iodine-123 metaiodobenzylguanidine-based risk model for the post-discharge risk stratification in patients with acute decompensated heart failure

Abstract Background A four-parameter risk model including cardiac iodine-123 metaiodobenzylguanidine (MIBG) imaging and readily available clinical parameters has been recently developed for the prediction of 2-year cardiac mortality risk in patients with chronic heart failure (CHF) using a Japanese CHF database consisting of 1322 patients. On the other hand, the Acute Decompensated Heart Failure National Registry (ADHERE) and Get With The Guidelines-Heart Failure (GWTG-HF) risk scores, simple tools to predict risk of in-hospital mortality, have been reported to be predictive of post-discharge outcome in patients with acute decompensated heart failure (ADHF). However, there is no information available on the usefulness of 2-year MIBG-based cardiac mortality risk score for the prediction of post-discharge prognosis in ADHF patients and its comparison with the ADHERE and GWTG-HF risk scores. Purpose We sought to validate the predictability of the 2-year MIBG-based cardiac mortality risk score for post-discharge clinical outcome in ADHF patients, and to compare its prognostic value with those of ADHERE and GWTG-HF risk scores. Methods We studied 297 consecutive patients who were admitted for ADHF, survived to discharge, and had definitive 2-year outcomes. Venous blood sampling was performed on admission, and echocardiography and cardiac MIBG imaging were performed just before discharge. In cardiac MIBG imaging, the cardiac MIBG heart-to-mediastinum ratio (HMR) was measured from the chest anterior view images obtained at 20 and 200 min after isotope injection. The 2-year cardiac mortality risk score was calculated using four parameters, including age, left ventricular ejection fraction, NYHA functional class, and HMR on delayed image. The patients were stratified into three groups based on the 2-year cardiac mortality risk score: low- (&lt;4%), intermediate- (4–12%), and high-risk (&gt;12%) groups. The ADHERE and GWTG-HF risk scores were also calculated from admission data as previously reported. The predictive ability of the scores was compared using receiver operating characteristic curve analysis. The endpoint was a composite of all-cause mortality and unplanned hospitalization for worsening heart failure. Results During a follow-up period, 110 patients reached the primary endpoint. There was significant difference in the rate of primary endpoint among the three groups stratified by 2-year cardiac mortality risk score (low-risk group: 18%, intermediate-risk group: 36%, high-risk group: 64%, Figure 1A). The 2-year cardiac mortality risk score demonstrated a greater area under the curve for the primary endpoint compared to the ADHERE and the GWTG-HF risk scores (Figure 1B). Figure 1 Conclusions The 2-year MIBG-based cardiac mortality risk score is also useful for the prediction of post-discharge clinical outcome in ADHF patients, and its prognostic value is superior to those of the ADHERE and the GWTG-HF risk scores.

Comparison between MRS and DWI in MRI of breast cancer

Introduction: Breast cancer is the most common cancer in women and is the second leading cause of cancer death (after lung cancer) in people throughout the world. Today, MRI is being used because of the limitations of x-ray mammography to detect breast cancer. Non-contrast sequences were associated to CE sequences in a breast MRI protocol for the sake of appraising morphologic features for lesion characterization. Two non-contrast MR methods that are mainly used for internal examination of breast tissue: proton MR spectroscopy (1H- MRS) and diffusion-weighted imaging (DWI). In the H-MRS, the total choline peak (tCho) is used as a biomarker for the detection of malignancies. Also, the DWI protocol determines the quantity by measuring the average diffusivity and Apparent diffusion coefficient(ADC). DWI showed that cell diffusivity is correlated with cellularity and tumor aggressiveness. Results: when looking at a clinical perspective, while MRS remained a research tool with important limitations, such as relatively long acquisition times, frequent low quality spectra, difficult standardization, and quantification of tCho tissue concentration. In contrast, the DWI has several advantages, one of its important advantages is its high sensitivity to detect breast cancer without the need for any ionizing radiation, or an isotope injection or any other contrast agent. Additionally, the acquisition time of DWI is relatively short and can be easily repeated to provide quantitative information. This technique is independent of the magnetic’s field strength. The results of two meta-analyzes revealed a overall sensitivity in the DWI of the breast 84 and 86%, and the overall specificity was 79% and 76% respectively ,These values in the MRS are between 71 to 74% and 78 to 88%, respectively40% to 60%. Conclusion: Finally, according to studies on MRS and DWI in breast MRI, are clearly in favor of an easier and more effective use of DWI.

Plant-microbe competition: does injection of isotopes of C and N into the rhizosphere effectively characterise plant use of soil N?

Despite considerable attention over the last 25yr, the importance of early protein breakdown products to plant nitrogen (N) nutrition remains uncertain. We used rhizosphere injection of 15 N-, 13 C- and 14 C-labelled inorganic N and amino acid (l-alanine), with chase periods from 1min to 24h, to investigate the duration of competition for amino acid between roots (Triticum aestivum) and soil microorganisms. We further investigated how microbial modification of l-alanine influenced plant carbon (C) and N recovery. From recovery of C isotopes, intact alanine uptake was 0.2-1.3% of added. Soil microbes appeared to remove alanine from soil solution within 1min and release enough NH4+ to account for all plant 15 N recovery (over 24h) within 5min. Microbially generated inorganic or keto acid C accounted for <25% of the lowest estimate of intact alanine uptake. Co-location of C and N labels appears a reasonable measure of intact uptake. Potential interference from microbially modified C is probably modest, but may increase with chase period. Similarly, competition for l-alanine is complete within a few minutes in soil, whereas NO3- added at the same rate is available for >24h, indicating that long chase periods bias outcomes and fail to accurately simulate soil processes.