Preliminary Experience with Small Animal SPECT Imaging on Clinical Gamma Cameras

The traditional lack of techniques suitable for in vivo imaging has induced a great interest in molecular imaging for preclinical research. Nevertheless, its use spreads slowly due to the difficulties in justifying the high cost of the current dedicated preclinical scanners. An alternative for lowering the costs is to repurpose old clinical gamma cameras to be used for preclinical imaging. In this paper we assess the performance of a portable device, that is, working coupled to a single-head clinical gamma camera, and we present our preliminary experience in several small animal applications. Our findings, based on phantom experiments and animal studies, provided an image quality, in terms of contrast-noise trade-off, comparable to dedicated preclinical pinhole-based scanners. We feel that our portable device offers an opportunity for recycling the widespread availability of clinical gamma cameras in nuclear medicine departments to be used in small animal SPECT imaging and we hope that it can contribute to spreading the use of preclinical imaging within institutions on tight budgets.This work was supported in part by public Fondo de Investigaciones Sanitarias ISCIII PS09/01206 and PI11/01806. P. Aguiar was awarded a public fellowship from Xunta de Galicia, POS-A/2013/001S

Preliminary experience with small animal SPECT imaging on clinical gamma cameras

The traditional lack of techniques suitable for in vivo imaging has induced a great interest in molecular imaging for preclinical research. Nevertheless, its use spreads slowly due to the difficulties in justifying the high cost of the current dedicated preclinical scanners. An alternative for lowering the costs is to repurpose old clinical gamma cameras to be used for preclinical imaging. In this paper we assess the performance of a portable device, that is, working coupled to a single-head clinical gamma camera, and we present our preliminary experience in several small animal applications. Our findings, based on phantom experiments and animal studies, provided an image quality, in terms of contrast-noise trade-off, comparable to dedicated preclinical pinhole-based scanners. We feel that our portable device offers an opportunity for recycling the widespread availability of clinical gamma cameras in nuclear medicine departments to be used in small animal SPECT imaging and we hope that it can contribute to spreading the use of preclinical imaging within institutions on tight budgets

Prognostic value of changes in the expression of stem cell markers in the peripheral blood of patients with colon cancer

Cancer stem cells play an important role in carcinogenesis and resistance to treatment and may lead to metastasis. The isolation of circulating stem cells involves cell sorting based on the presence of cell surface markers. Many surface markers such as CD133, c-Kit, SOX, OCT4 and TWIST have been reported. In the present study, we determined the expression of different stem cell markers and their variation in expression at different stages of the treatment process. Samples of EDTA blood were collected from metastatic colorectal cancer patients, and circulating cancer stem cells were isolated for the analysis of the expression of stem cell markers using RT-PCR. These findings were correlated with the response to therapy. All statistical analyses were performed using the GraphPad Prism 5.03 software. Significant differences were found in the expression levels of the markers CD133, SOX2, OCT4 and TWIST1. No differences were found in c-Kit expression. Correlation in the expression levels of most of the markers was observed. Expression of CD133, OCT4, SOX2 and TWIST1 had a predictive value for colon cancer behavior. Evaluation of this stem cell gene expression panel may be useful for predicting the response during the process of treatment, and the relative easy access to samples facilitates this method. Moreover the correlation between CD133 and TWIST1 expression may be associated with tumor regrowth and metastatic relapse

Clinicopathological characteristics of infiltrating lobular breast carcinoma in elderly women: Preliminary results

This study was conducted to investigate the clinicopathological parameters in elderly women (aged >70 years) with infiltrating lobular carcinoma (ILC) of the breast and compare the results with those obtained from younger patients (aged 55-70 years). The study sample included a total of 46 women with ILCs, 10 aged >70 and 36 aged 55-70 years. The parameters analysed were tumor size, histological grade (HG), axillary lymph node involvement, distant metastasis and immunohistochemical expression of estrogen, progesterone and androgen receptors, Ki67, p53 and B cell lymphoma 2. Compared to women aged 55-70 years, ILCs in women aged >70 years were commonly of larger size (P=0.068) and were more frequently HG3 (P=0.024). There were no statistically significant differences in the other parameters analysed. Furthermore, we were unable to determine differences in cancer recurrence and mortality in the two patient subgroups during our follow-up. In conclusion, our preliminary results, based on the limited number of cases included in this study, indicate that i) ILCs in women aged >70 years tended to be larger compared to those in women aged 55-70 years and were more frequently of grade 3; and ii) there were no significant differences in terms of recurrence and mortality between the two patient subgroups during our follow-up

Association between tumor size and immunohistochemical expression of Ki-67, p53 and BCL2 in a node-negative breast cancer population selected from a breast cancer screening program

BACKGROUND/AIM: Breast cancer is the most common type of cancer among women. Breast infiltrating ductal carcinoma (IDC) is the most common type of breast cancer, approximately 80% of all breast carcinomas. The aim of this study was to analyze the association of tumor size, evaluated after histopathological analysis, with different clinical and biological parameters in IDC. MATERIALS AND METHODS: The study group included 251 women with IDC without axillary lymph node involvement, aged between 27 and 81 years. Analyzed parameters were: age, histological grade, menopausal status, menarche, pregnancy, abortion, breastfeeding, contraceptive use, hormone replacement therapy, estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), Ki-67, p53 and BCL2. RESULTS: Pathological tumor size was between 0.2 and 5.1 cm (1.43±0.86 cm). Tumors in 45 cases exceeded 2 cm, in eight 3 cm and only in one 5 cm. Pathological size was significantly associated with age >70 vs. 70 years, histological grade 3 and immunohistochemically-augmented expression of Ki-67 and p53

CA15.3 Serum Concentrations in Older Women with Infiltrating Ductal Carcinomas of the Breast

Breast cancer is currently becoming a disease of the elderly. We have studied the relation between CA 15.3 serum concentrations and clinical-pathological parameters in 69 women with IDC aged over 70 years (76.3 ± 4.2; range: 71–88; median 76). A group of 205 women with the same tumor but aged <70 years (62.8 ± 4.0; range: 55–70; median 63) was also considered for comparison. Tumor size, axillary lymph node involvement, distant metastasis and histological grade were taken account. Serum CA 15.3 was determined by luminescence assay. CA 15.3 serum concentrations ranged between 6 and 85 U/mL (median 22.9 U/mL), and were higher only in patients with greater (qualitative and quantitative; p: 0.041) tumor size. Our results show that in women with IDCs, and aged over 70 years, serum CA 15.3 serum concentrations are associated exclusively with a greater tumor size, being these findings different to those described in women with the same subtype of tumor considered as a whole or with lower age.This work was supported by grant PI11/01806 from ISCIII (Spain)S

Structure of the catalytic sites in Fe/N/C-catalysts for O-2-reduction in PEM fuel cells

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Fe-based catalytic sites for the reduction of oxygen in acidic medium have been identified by 57Fe Mössbauer spectroscopy of Fe/N/C catalysts containing 0.03 to 1.55 wt% Fe, which were prepared by impregnation of iron acetate on carbon black followed by heat-treatment in NH3 at 950 °C. Four different Fe-species were detected at all iron concentrations: three doublets assigned to molecular FeN4-like sites with their ferrous ions in a low (D1), intermediate (D2) or high (D3) spin state, and two other doublets assigned to a single Fe-species (D4 and D5) consisting of surface oxidized nitride nanoparticles (FexN, with x ≤ 2.1). A fifth Fe-species appears only in those catalysts with Fe-contents ≥0.27 wt%. It is characterized by a very broad singlet, which has been assigned to incomplete FeN4-like sites that quickly dissolve in contact with an acid. Among the five Fe-species identified in these catalysts, only D1 and D3 display catalytic activity for the oxygen reduction reaction (ORR) in the acid medium, with D3 featuring a composite structure with a protonated neighbour basic nitrogen and being by far the most active species, with an estimated turn over frequency for the ORR of 11.4 e− per site per s at 0.8 V vs. RHE. Moreover, all D1 sites and between 1/2 and 2/3 of the D3 sites are acid-resistant. A scheme for the mechanism of site formation upon heat-treatment is also proposed. This identification of the ORR-active sites in these catalysts is of crucial importance to design strategies to improve the catalytic activity and stability of these materials

Distinctive waves of innate immune response in the retina in experimental autoimmune encephalomyelitis

Neurodegeneration mediates neurological disability in inflammatory demyelinating diseases of the CNS. The role of innate immune cells in mediating this damage has remained controversial with evidence for destructive and protective effects. This has complicated efforts to develop treatment. The time sequence and dynamic evolution of the opposing functions are especially unclear. Given limits of in vivo monitoring in human diseases such as multiple sclerosis (MS), animal models are warranted to investigate the association and timing of innate immune activation with neurodegeneration. Using noninvasive in vivo retinal imaging of experimental autoimmune encephalitis (EAE) in CX3CR1GFP/+–knock-in mice followed by transcriptional profiling, we are able to show 2 distinct waves separated by a marked reduction in the number of innate immune cells and change in cell morphology. The first wave is characterized by an inflammatory phagocytic phenotype preceding the onset of EAE, whereas the second wave is characterized by a regulatory, antiinflammatory phenotype during the chronic stage. Additionally, the magnitude of the first wave is associated with neuronal loss. Two transcripts identified — growth arrest–specific protein 6 (GAS6) and suppressor of cytokine signaling 3 (SOCS3) — might be promising targets for enhancing protective effects of microglia in the chronic phase after initial injury

Smoothelin-like 2 Inhibits Coronin-1B to Stabilize the Apical Actin Cortex during Epithelial Morphogenesis

The actin cortex is involved in many biological processes and needs to be significantly remodeled during cell differentiation. Developing epithelial cells construct a dense apical actin cortex to carry out their barrier and exchange functions. The apical cortex assembles in response to three-dimensional (3D) extracellular cues, but the regulation of this process during epithelial morphogenesis remains unknown. Here, we describe Smoothelin-like 2 (SMTNL2) function, a member of the smooth-muscle related Smoothelin protein family, in apical cortex maturation. SMTNL2 is induced during the development of multiple epithelial tissues and localizes to the apical and junctional actin cortex in intestinal and kidney epithelial cells. SMTNL2 deficiency leads to membrane herniations in the apical domain of epithelial cells, indicative of cortex abnormalities. We find that SMTNL2 binds to actin filaments and is required to slow down the turnover of apical actin. We also characterize the SMTNL2 proximal interactome and find that SMTNL2 executes its functions partly through inhibition of Coronin-1B. While Coronin-1B-mediated actin dynamics are required for early morphogenesis, its sustained activity is detrimental for the mature apical shape. SMTNL2 binds to Coronin-1B through its N-terminal coiled-coil region and negates its function to stabilize the apical cortex. In sum, our results unveil a mechanism for regulating actin dynamics during epithelial morphogenesis, providing critical insights on the developmental control of the cellular corte

International standardisation work on the measurement of radon in air and water

Radon is considered to be the main source of human exposure to natural radiation. As stated by the World Health Organization, the exposure due to the inhalation of indoor radon is much greater than the one via the ingestion of water as radon degasses from water during handling. In response to these concerns about the universal presence of radon, environmental assessment studies are regularly commissioned to assess the radon exposure of public and workers. The credibility of such studies relies on the quality and reliability of radon analysis as well as on the sample representativeness of the radiological situation. The standard-setting approach, based on consensus, seemed to lend itself to a settlement of technical aspects of potential comparison. At present, two Working Groups of the International Standardization Organization are focussing on drafting standards on radon and its decay products measurement in air and water. These standards, which aim for a set of rigorous metrology practices, will be useful for persons in charge of the initial characterisation of a site with respect to natural radioactivity as well as to those performing the routine surveillance of specific site