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Coralline algae form complex habitats which are biodiversity hotspots. Experimental studies suggest that climate change will decrease coralline algal structural integrity. These experiments, however, lack information on local morphological variability and how much structural change would be needed to threaten habitat formation. Here, using finite element modelling, we assess variability in cellular structure and chemical composition of the carbonate skeleton of four coralline algal species from Britain in contemporary and historical specimens collected over the last 130 years. Cellular and mineral properties are highly variable within species, between sites and through time, with structurally weaker cells in the southern species and contemporary material compared to northern taxa and historical material. Yet, temporal differences in strength were smaller than spatial differences. Our work supports long term experiments which show the adaptation potential of this group. Our results suggest that future anthropogenic climate change may lead to loss of habitat complexity in the south and expansion of structurally weaker southern species into northern sites. [ABSTRACT FROM AUTHOR]

Hintergrund: Auch durch die neue Personalverordnung wird die Peer- und Genesungsbegleitung zunehmend relevant. Dadurch stellt sich die Frage, welche individuellen Gelingensbedingungen es für die Implementierung von Peer- und Genesungsbegleitung gibt.Diese Arbeit ist ein Teilprojekt der vom Innovationsfonds finanzierten ImpPeer-Psy5-Studie, die bundesweite Anforderungen an die Implementierung von Peer- und Genesungsbegleitung in der krankenkassenfinanzierten Versorgung (SGB V) untersucht. 57 problemzentrierte Interviews mit Peer- und Genesungsbegleiter*innen (PGB), Mitarbeiter*innen (MA) und Nutzer*innen sowie eine darauf aufbauende Fokusgruppe wurden mithilfe einer vergleichenden thematischen Analyse untersucht. Diese Arbeit wurde vorrangig durch eine Forscherin umgesetzt, die über eigene Krisen- und Psychiatrieerfahrungen verfügt.Aus Sicht der befragten MA sind Sympathie und Persönlichkeit zentrale Faktoren für eine gelingende Implementierung der Peer- und Genesungsbegleitung. Demgegenüber stehen für die PGB ein professionalisierter Umgang mit der eigenen Krisen- und Recovery-Erfahrung sowie diverse Lebens- und berufliche Vorerfahrungen im Vordergrund.Um die Impulse der Peer- und Genesungsbegleitung wirksam aufzunehmen, braucht es eine Anerkennung der professionellen Identität der PGB. Insbesondere Settings, die Aufgaben zwischen den Berufsgruppen weniger hierarchisch trennen und v. a. auf Beziehungsarbeit setzen, wie das der Zuhausebehandlung, sind für die Implementierung von PGB besonders geeignet.Methode: Auch durch die neue Personalverordnung wird die Peer- und Genesungsbegleitung zunehmend relevant. Dadurch stellt sich die Frage, welche individuellen Gelingensbedingungen es für die Implementierung von Peer- und Genesungsbegleitung gibt.Diese Arbeit ist ein Teilprojekt der vom Innovationsfonds finanzierten ImpPeer-Psy5-Studie, die bundesweite Anforderungen an die Implementierung von Peer- und Genesungsbegleitung in der krankenkassenfinanzierten Versorgung (SGB V) untersucht. 57 problemzentrierte Interviews mit Peer- und Genesungsbegleiter*innen (PGB), Mitarbeiter*innen (MA) und Nutzer*innen sowie eine darauf aufbauende Fokusgruppe wurden mithilfe einer vergleichenden thematischen Analyse untersucht. Diese Arbeit wurde vorrangig durch eine Forscherin umgesetzt, die über eigene Krisen- und Psychiatrieerfahrungen verfügt.Aus Sicht der befragten MA sind Sympathie und Persönlichkeit zentrale Faktoren für eine gelingende Implementierung der Peer- und Genesungsbegleitung. Demgegenüber stehen für die PGB ein professionalisierter Umgang mit der eigenen Krisen- und Recovery-Erfahrung sowie diverse Lebens- und berufliche Vorerfahrungen im Vordergrund.Um die Impulse der Peer- und Genesungsbegleitung wirksam aufzunehmen, braucht es eine Anerkennung der professionellen Identität der PGB. Insbesondere Settings, die Aufgaben zwischen den Berufsgruppen weniger hierarchisch trennen und v. a. auf Beziehungsarbeit setzen, wie das der Zuhausebehandlung, sind für die Implementierung von PGB besonders geeignet.Ergebnisse: Auch durch die neue Personalverordnung wird die Peer- und Genesungsbegleitung zunehmend relevant. Dadurch stellt sich die Frage, welche individuellen Gelingensbedingungen es für die Implementierung von Peer- und Genesungsbegleitung gibt.Diese Arbeit ist ein Teilprojekt der vom Innovationsfonds finanzierten ImpPeer-Psy5-Studie, die bundesweite Anforderungen an die Implementierung von Peer- und Genesungsbegleitung in der krankenkassenfinanzierten Versorgung (SGB V) untersucht. 57 problemzentrierte Interviews mit Peer- und Genesungsbegleiter*innen (PGB), Mitarbeiter*innen (MA) und Nutzer*innen sowie eine darauf aufbauende Fokusgruppe wurden mithilfe einer vergleichenden thematischen Analyse untersucht. Diese Arbeit wurde vorrangig durch eine Forscherin umgesetzt, die über eigene Krisen- und Psychiatrieerfahrungen verfügt.Aus Sicht der befragten MA sind Sympathie und Persönlichkeit zentrale Faktoren für eine gelingende Implementierung der Peer- und Genesungsbegleitung. Demgegenüber stehen für die PGB ein professionalisierter Umgang mit der eigenen Krisen- und Recovery-Erfahrung sowie diverse Lebens- und berufliche Vorerfahrungen im Vordergrund.Um die Impulse der Peer- und Genesungsbegleitung wirksam aufzunehmen, braucht es eine Anerkennung der professionellen Identität der PGB. Insbesondere Settings, die Aufgaben zwischen den Berufsgruppen weniger hierarchisch trennen und v. a. auf Beziehungsarbeit setzen, wie das der Zuhausebehandlung, sind für die Implementierung von PGB besonders geeignet.Schlussfolgerungen: Auch durch die neue Personalverordnung wird die Peer- und Genesungsbegleitung zunehmend relevant. Dadurch stellt sich die Frage, welche individuellen Gelingensbedingungen es für die Implementierung von Peer- und Genesungsbegleitung gibt.Diese Arbeit ist ein Teilprojekt der vom Innovationsfonds finanzierten ImpPeer-Psy5-Studie, die bundesweite Anforderungen an die Implementierung von Peer- und Genesungsbegleitung in der krankenkassenfinanzierten Versorgung (SGB V) untersucht. 57 problemzentrierte Interviews mit Peer- und Genesungsbegleiter*innen (PGB), Mitarbeiter*innen (MA) und Nutzer*innen sowie eine darauf aufbauende Fokusgruppe wurden mithilfe einer vergleichenden thematischen Analyse untersucht. Diese Arbeit wurde vorrangig durch eine Forscherin umgesetzt, die über eigene Krisen- und Psychiatrieerfahrungen verfügt.Aus Sicht der befragten MA sind Sympathie und Persönlichkeit zentrale Faktoren für eine gelingende Implementierung der Peer- und Genesungsbegleitung. Demgegenüber stehen für die PGB ein professionalisierter Umgang mit der eigenen Krisen- und Recovery-Erfahrung sowie diverse Lebens- und berufliche Vorerfahrungen im Vordergrund.Um die Impulse der Peer- und Genesungsbegleitung wirksam aufzunehmen, braucht es eine Anerkennung der professionellen Identität der PGB. Insbesondere Settings, die Aufgaben zwischen den Berufsgruppen weniger hierarchisch trennen und v. a. auf Beziehungsarbeit setzen, wie das der Zuhausebehandlung, sind für die Implementierung von PGB besonders geeignet. [ABSTRACT FROM AUTHOR]

Copyright of Kölner Zeitschrift für Soziologie und Sozialpsychologie ( KZfSS) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The major depressive disorder is one of the most common mental illnesses worldwide. Current treatment standards recommend a combined therapy with medication and psychotherapy. As an additive component and to further improvements in treatment, physical activity such as yoga may be integrated into conventional treatment. This study investigates the impact of a 3-month body-oriented yoga in patients with major depressive disorder (MDD). In total, n = 83 patients were included. An intervention group received a vigorous Ashtanga-Yoga three times a week. The waiting-list control group obtained a treatment as usual (TAU). As a primary outcome depression scores (Beck Depression Inventory-II (BDI-II), Montgomery Asberg Depression Rating Scale (MADRS)) were tested at three time points. Secondary outcome was the positive and negative affect [Positive and Negative Affect Scale (PANAS)] and remission rates. To analyze the data, multilevel models and effect sizes were conducted. The results showed an improvement in BDI-II scores for both groups over time [γ = − 3.46, t(165) = − 7.99, p < 0.001] but not between groups [γ = 0.98, t(164) = 1.12, p = 0.263]. An interaction effect (time x group) occurred for MADRS [γ = 2.10, t(164) = 2.10, p < 0.038]. Positive affects improved over time for both groups [γ = 1.65, t(165) = 4.03, p < 0.001]. Negative affects decreased for all over time [γ = − 1.00, t(165) = − 2.51, p = 0.013]. There were no significant group differences in PANAS. Post hoc tests revealed a greater symptom reduction within the first 6 weeks for all measurements. The effect sizes for depression scores showed a positive trend. Remission rates indicated a significant improvement in the yoga group (BDI-II: 46.81%, MADRS: 17.02%) compared to the control group (BDI: 33.33%, MADRS: 8.33%). The findings suggest that there is a trendsetting additive effect of Ashtanga-Yoga after 3 months on psychopathology and mood with a greater improvement at the beginning of the intervention. Further research in this field can help to achieve more differentiated results. [ABSTRACT FROM AUTHOR]

Despite the economic and ecological importance of corals' skeletal structure, as well as their predicted vulnerability to future climate change, few studies have examined the skeletal mechanical properties at the nanoscale. As climate change is predicted to alter coral growth and physiology, as well as increase mechanical stress events (e.g., bioerosion, storm frequency), it is crucial to understand how skeletal mechanical properties change with environmental conditions. Moreover, while material properties are intimately linked to the chemical composition of the skeleton, no previous study has examined mechanical properties alongside carbonate geochemical composition. Using Porites coral cores from a wide range of reef environments (Thailand, Singapore, Taiwan), we correlated coral's micro-mechanical properties with chemical composition. In contrast to previous mechanical measurements of reef-building corals, we document unprecedented variability in the hardness, stiffness, and micro-cracking stress of Porites corals across reef environments, which may significantly decrease the structural integrity of reef substrate. Corals from environments with low salinity and high sedimentation had higher organic content and fractured at lower loads, suggesting that skeletal organic content caused enhanced embrittlement. Within individual coral cores, we observed seasonal variability in skeletal stiffness, and a relationship between high sea surface temperature, increased stiffness, and high-density. Regionally, lower Sr/Ca and higher Mg/Ca coincided with decreased stiffness and hardness, which is likely driven by increased amorphous calcium carbonate and skeletal organic content. If the coral is significantly embrittled, as measured here in samples from Singapore, faster erosion is expected. A decrease in skeletal stiffness will decrease the quality of reef substrate, enhance the rate of bioerosion by predators and borers, and increase colony dislodgement, resulting in widespread loss of structural complexity. [ABSTRACT FROM AUTHOR]

Detailed knowledge about radiation exposure is crucial for radiology professionals. The conventional calculation of effective dose (ED) for computed tomography (CT) is based on dose length product (DLP) and population-based conversion factors (k). This is often imprecise and unable to consider individual patient characteristics. We sought to provide more precise and individual radiation exposure calculation using image based Monte Carlo simulations (MC) in a heterogeneous patient collective and to compare it to phantom based MC provided from the National Cancer Institute (NCI) as academic reference. Dose distributions were simulated for 22 patients after whole-body CT during Positron Emission Tomography-CT. Based on MC we calculated individual Lifetime Attributable Risk (LAR) and Excess Relative Risk (ERR) of cancer mortality. EDMC was compared to EDDLP and EDNCI. EDDLP (13.2 ± 4.5 mSv) was higher compared to EDNCI (9.8 ± 2.1 mSv) and EDMC (11.6 ± 1.5 mSv). Relative individual differences were up to −48% for EDMC and −44% for EDNCI compared to EDDLP. Matching pair analysis illustrates that young age and gender are affecting LAR and ERR significantly. Because of these uncertainties in radiation dose assessment automated individual dose and risk estimation would be desirable for dose monitoring in the future. [ABSTRACT FROM AUTHOR]

Introduction: The response to induction chemotherapy (IC) predicts local control after conservative treatment of laryngeal, meso- and hypopharyngeal head and neck squamous cell carcinoma (HNSCC) and can thus help to avoid surgery. Single-cycle induction chemotherapy may help to maintain a low local recurrence rate while keeping the overall toxicity manageable. However, long-term data on single-cycle IC response by tumor location is lacking. Methods: N = 102 patients with functionally inoperable primary HNSCC of the larynx (n = 43), hypopharynx (n = 42) or mesopharynx/tongue (n = 17) received one cycle of docetaxel (75 mg/m2, d1) plus cisplatin (30 mg/m2, d1-3) or carboplatin (AUC 1.5, d1-3) and a response evaluation 3 weeks later. Responders (≥ 30% tumor size reduction and ≥ 20% SUVmax decrease in 18F-FDG PET/CT) were recommended chemoradiotherapy (CRT), and non-responders surgery. Results: The overall response rate was 72.5%. All 74 responders and 10 non-responders received primary CRT, and 18 patients received primary surgery after single-cycle IC. Overall 10-year local recurrence-free survival (LRFS) was 73.7%. Three-year LRFS was 88.2% (mesopharynx/tongue), 88.2% (larynx), and 73.3% (hypopharynx); p = 0.17. 3-year distant metastasis-free survival (DMFS) was 94.1% (mesopharynx/tongue), 88.0% (larynx) and 76.4% (hypopharynx); p > 0.05. This influenced the 3-year cancer-specific survival (CSS) for larynx (91.2%) vs. hypopharynx tumors (60.8%); p = 0.003, but CSS was not different to tumors in the mesopharynx/tongue (81.4%); p > 0.05. Conclusions: A single-cycle induction chemotherapy for HNSCC enables surgery plus adjuvant therapy as well as chemoradiotherapy. The long-term local and distant disease control was good but varied between tumors in the larynx and mesopharynx/tongue vs. hypopharynx. [ABSTRACT FROM AUTHOR]

The use of non-metallic composites at floor gratings in offshore platforms is driven by the need for increased component life in corrosive environments. As a result, these floor gratings contribute to a lower demand for maintenance and greater operational continuity. However, these composite materials have limitations when are exposed to high temperatures. The application of these floor gratings, on ships and floating offshore platforms have the requirement to retain a significant level of mechanical integrity during and after exposure to a fire. In this work, the mechanical behavior of two composites materials after being subject to a temperature rise was evaluated. One composite has an isophthalic polyester resin as matrix and the other used a phenolic resin. Before the mechanical characterization, thermogravimetric analysis was performed to determine the temperatures of beginning of the thermal degradation, and the microstructure of the composites was evaluated by digital image analysis. From the results of the thermal analysis a temperature of 250°C was chosen as the maximum one to be used, in order to evaluate the behavior of these composites in regions close to fire but not directly exposed to fire. Flexural properties of the two composites were performed by three-point bending test with 25 specimens of each composite. For the phenolic resin composite, the test specimens were manufactured with the average dimensions of 90.5 mm long, 19.5 mm large and 4.2 mm thick. The average dimensions of isophthalic composite specimens were 135.0 mm long, 25.0 mm large and 6.9 mm thick. The results show that the isophthalic resin matrix composite lost its mechanical integrity with the time of exposure to temperature, while the phenolic matrix composite maintained their properties. For example, regarding the maximum flexural stress a decrease of almost 50% was measured for the isophthalic matrix composite in comparison to only 3% for the phenolic matrix composite. However, the mechanical behavior of this composite was impaired by the presence of a high content of voids (5.7%) and of touching fibers arising from the manufacturing process. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to evaluate the outcome of treatment-naive patients with synchronous metastatic rectal cancer after chemotherapy with FOLFOXIRI followed by local therapeutic procedures of all tumor lesions as complete as possible.Methods: We reviewed data of 30 patients with synchronous distant metastatic rectal cancer who underwent chemotherapy with FOLFOXIRI and subsequent local therapy in our institution.Results: Median follow-up was 28 months (range: 8; 74). Cumulative overall survival (OS) and progression-free survival (PFS) was 93.3, 76.9, 55.6% and 46.2, 29.7, 29.7% after 1, 2, 4 years. Non-response to chemotherapy with FOLFOXIRI was associated with a highly significant decreased OS (p < 0.0001). The consistent use of local ablative procedures led to a statistically significant increase in OS (p < 0.0001), but not in PFS (p = 0.635). Patients with ≤ 4 distant metastases showed a better OS (p = 0.033).Conclusions: Response to intensified first-line chemotherapy with FOLFOXIRI, treatment of the primary rectal tumor, and repeated thorough local ablative procedures in patients with synchronous metastasized rectal cancer may lead to long-term survival, even in a subset of patients with unresectable disease at initial diagnosis. [ABSTRACT FROM AUTHOR]

Purpose: We aimed at evaluating the role of 68Ga-PSMA-11 PET/CT-derived metabolic parameters for assessment of whole-body tumor burden and its capability to determine therapeutic response in patients with prostate cancer.Methods: A total of 142 patients with biochemical recurrence of prostate cancer underwent PET/CT with [68Ga]Ga-PSMA-HBED-CC (68Ga-PSMA-11). Quantitative assessment of all 641 68Ga-PSMA-11-positive lesions in the field of view was performed to calculate PSMA-derived parameters, including whole-body PSMA tumor volume (PSMA-TV) and whole-body total lesion PSMA (TL-PSMA), as well as the established SUVmax and SUVmean values. All PET-derived parameters were tested for correlation with serum PSA levels and for association with Gleason scores.In 23 patients who underwent 68Ga-PSMA-11 PET/CT before and after therapy with either external beam radiation, androgen deprivation, or docetaxel chemotherapy, SUVmax and TL-PSMA were compared to radiographic response assessment of CT images based on RECIST 1.1 criteria and to biochemical response determined by changes of serum PSA levels.Results: PSMA-TV and TL-PSMA demonstrated a significant correlation with serum PSA levels (P < 0.0001) and TL-PSMA was significantly different for different Gleason scores. The agreement rate between TL-PSMA derived from PET and biochemical response was 87% (95% confidence interval, 0.66-0.97; Cohen’s κ = 0.78; P < 0.01) and, thus, higher than for SUVmax, which was 74% (95% CI, 0.52-0.90; κ = 0.55; P < 0.01). Furthermore, agreement with PSA was higher for TL-PSMA and SUVmax than for CT-based response evaluation. Discordant findings between PET and CT were most likely due to limitations of CT and RECIST in rating small lymph nodes as metastases, as well as bone involvement, which was sometimes not detectable in CT.Conclusion: 68Ga-PSMA-11 PET/CT-derived metabolic tumor parameters showed promising results for evaluation of treatment response. Especially, TL-PSMA demonstrated higher agreement rates with biochemical response compared to SUVmax. Larger, ideally prospective trials are needed to help to reveal the full potential of metabolic parameters derived from PET imaging with 68Ga-PSMA-11. [ABSTRACT FROM AUTHOR]

Copyright of Journal for Labour Market Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Somatic embryogenesis is a morphogenetic route useful for the study of embryonic development, as well as the large-scale propagation of endangered species, such as the Brazilian pine ( Araucaria angustifolia). In the present study, we investigated the morphological and ultrastructural organization of A. angustifolia somatic embryo development by means of optical and electron microscopy. The proembryogenic stage was characterized by the proliferation of proembryogenic masses (PEMs), which are cellular aggregates composed of embryogenic cells (ECs) attached to suspensor-like cells (SCs). PEMs proliferate through three developmental stages, PEM I, II, and III, by changes in the number of ECs and SCs. PEM III-to-early somatic embryo (SE) transition was characterized by compact clusters of ECs growing out of PEM III, albeit still connected to it by SCs. Early SEs showed a dense globular embryonic mass (EM) and suspensor region (SR) connected by embryonic tube cells (TCs). By comparison, early somatic and zygotic embryos showed similar morphology. ECs are round with a large nucleus, nucleoli, and many cytoplasmic organelles. In contrast, TCs and SCs are elongated and vacuolated with cellular dismantling which is associated with programmed cell death of SCs. Abundant starch grains were observed in the TCs and SCs, while proteins were more abundant in the ECs. Based on the results of this study, a fate map of SE development in A. angustifolia is, for the first time, proposed. Additionally, this study shows the cell biology of SE development of this primitive gymnosperm which may be useful in evolutionary studies in this area. [ABSTRACT FROM AUTHOR]

Understanding whether marine calcifying organisms may acclimatise to climate change is important with regard to their survival over the coming century. Due to cold waters having a naturally higher CO uptake, the Southern Ocean provides an especially good opportunity to study the potential impact of climate change. In 2011, a new cheilostome bryozoan species- Chiastosella ettorina sp. nov.-was dredged from Burdwood Bank, Southern Ocean, at 324-219-m depth during the Nathaniel B Palmer Cruise. This species had previously been collected in 1902 from the same area at 100-m depth, but was incorrectly identified as Chiastosella watersi, an encrusting species from New Zealand. The availability of samples of the same species, from the same general location, but collected 109 years apart allowed us to investigate morphological modifications potentially arising from environmental changes. We found a significant difference in zooid size, with the oldest and shallowest specimens having smaller zooids than the recently collected deeper specimens. This difference in zooid size appears to be unrelated to known sources of environmental variation such as temperature and salinity, and it could represent the extremes of the zooid size range of C. ettorina. An alternative explanation is that acidifying waters may have caused zooids to grow more slowly, resulting in a final larger size. [ABSTRACT FROM AUTHOR]

Purpose: PET/MR hybrid scanners have recently been introduced, but not yet validated. The aim of this study was to compare the PET components of a PET/CT hybrid system and of a simultaneous whole-body PET/MR hybrid system with regard to reproducibility of lesion detection and quantitation of tracer uptake. Methods: A total of 46 patients underwent a whole-body PET/CT scan 1 h after injection and an average of 88 min later a second scan using a hybrid PET/MR system. The radioactive tracers used were F-deoxyglucose (FDG), F-ethylcholine (FEC) and Ga-DOTATATE (Ga-DOTATATE). The PET images from PET/CT (PET) and from PET/MR (PET) were analysed for tracer-positive lesions. Regional tracer uptake in these foci was quantified using volumes of interest, and maximal and average standardized uptake values (SUV and SUV, respectively) were calculated. Results: Of the 46 patients, 43 were eligible for comparison and statistical analysis. All lesions except one identified by PET were identified by PET (99.2 %). In 38 patients (88.4 %), the same number of foci were identified by PET and by PET. In four patients, more lesions were identified by PET than by PET, in one patient PET revealed an additional focus compared to PET. The mean SUV and SUV of all lesions determined by PET were by 21 % and 11 % lower, respectively, than the values determined by PET ( p < 0.05), and a strong correlation between these variables was identified (Spearman rho 0.835; p < 0.01). Conclusion: PET/MR showed equivalent performance in terms of qualitative lesion detection to PET/CT. The differences demonstrated in quantitation of tracer uptake between PET and PET were minor, but statistically significant. Nevertheless, a more detailed study of the quantitative accuracy of PET and the factors governing it is needed to ultimately assess its accuracy in measuring tissue tracer concentrations. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate DNA double-strand breaks (DSBs) in blood lymphocytes of patients undergoing positron emission tomography (PET)/CT using γ-H2AX immunofluorescence microscopy and to differentiate between F-fluorodeoxyglucose (FDG) and CT-induced DNA lesions. Methods: This study was approved by the local Ethics Committee and complies with Health Insurance Portability and Accountability Act (HIPAA) requirements. After written informed consent was obtained, 33 patients underwent whole-body F-FDG PET/CT (3 MBq/kg body weight, 170/100 reference mAs at 120 kV). The FDG PET and CT portions were performed as an initial CT immediately followed by the PET. Blood samples were obtained before, at various time points following F-FDG application and up to 24 h after the CT scan. Distinct foci representing DSBs were quantified in isolated lymphocytes using fluorescence microscopy after staining against the phosphorylated histone variant γ-H2AX. Results: The DSB values at the various time points were significantly different ( p < 0.001). The median baseline level was 0.08/cell (range 0.06-0.12/cell). Peaks of radiation-induced DSBs were found 30 min after F-FDG administration (median excess foci 0.11/cell, range 0.06-0.27/cell) and 5 min after CT (median excess foci 0.17/cell, range 0.05-0.54/cell). A significant correlation between CT-induced DSBs and dose length product was obtained ( ρ = 0.898, p < 0.001). After 24 h DSB values were still slightly but significantly elevated (median foci 0.11/cell, range 0.10-0.14/cell, p = 0.003) compared to pre-exposure levels. Conclusion: PET/CT-induced DSBs can be monitored using γ-H2AX immunofluorescence microscopy. Peak values may be obtained 30 min after F-FDG injection and 5 min after CT. The radionuclide contributes considerably to the total DSB induction in this setting. [ABSTRACT FROM AUTHOR]

In Alzheimer disease, CSF biomarkers and nuclear imaging are of particular interest. Many studies investigated only one technique, limiting comparison. Here, in 76 patients blinded 99mTc-SPECT was compared to CSF. Sensitivity of CSF was 92%; and 51% for SPECT. Specificity favored SPECT (90 vs. 80%). Both techniques showed no coherence ( p = 0.17–0.47). Our results confirm that CSF biomarkers show higher sensitivity. SPECT has higher specificity and can also be used for other dementias without established CSF biomarkers. [ABSTRACT FROM AUTHOR]

Hybrid imaging combining single photon emission computed tomography (SPECT) with 131I and X-ray computed tomography (CT) performed at radioablation (RA) for thyroid carcinoma more accurately detects regional lymph node metastases (LNM) than does planar imaging. In this bicentric prospective study we used hybrid imaging in conjunction with histopathological examination to measure LNM frequency in a consecutive group of patients referred for RA due to stage T1 papillary thyroid carcinoma (PTC). At the Departments of Nuclear Medicine of the Ludwig Maximilian University of Munich and the Friedrich Alexander University of Erlangen-Nuremberg SPECT/spiral CT is routinely performed in all PTC subjects at the time of RA. Screening of our SPECT/CT databases for PTC patients with T1 histology produced 98 patients from Munich and 53 patients from Erlangen, including 96 of 151 patients with microcarcinoma. In 69 patients of the entire group, cervical lymph node dissection had been performed, whereas nodal staging in the remaining 82 subjects was based on SPECT/CT. LNM incidence in the whole group was 26% [95% confidence interval (CI): 20–33%] versus 22% (95% CI: 15–31%) in the microcarcinoma subgroup. SPECT/CT was more accurate in 24.5% of our patients than planar imaging with regard to nodal staging. LNM occurs in one quarter of all patients with T1 PTC, and also in the subset with microcarcinoma. Performing 131I SPECT/CT, either with therapeutic or diagnostic radioactivities, directly after thyroidectomy should provide more accurate staging of T1 PTC, thus facilitating optimal therapeutic management. [ABSTRACT FROM AUTHOR]

In differentiated thyroid carcinoma (DTC), 131I-SPECT/CT is more accurate in identifying radioiodine-positive lymph node metastases (LNM) than planar whole-body scans (WBS). The purpose of this study was to investigate the value of 131I-SPECT/CT performed at the first radioablation to predict the occurrence and/or persistence of cervical radioiodine-positive LNM 5 months later. The study included 81 DTC patients that had had SPECT/ spiral CT after radioablation of thyroid remnants after thyroidectomy. The patients were re-examined 5 months later using 131I-WBS performed at TSH stimulation. In addition, SPECT/CT of the neck was performed in patients with iodine-positive cervical foci to distinguish between thyroid remnant and LNM. The outcome variable of the study was the detection or exclusion of iodine-positive cervical LNM. Of 61 patients without a SPECT/CT diagnosis of 131I-positive LNM at radioablation, 60 had no 131I-positive LNM at follow-up. In the remaining patient of this group, a new radioiodine-positive LNM was detected. In 17 of 20 patients with a SPECT/CT diagnosis of 131I-positive LNM ( n = 19) or an indeterminate lesion ( n = 1) at first radioablation, no 131I-positive LNM were detected 5 months later. Radioiodine-positive LNM persisted in three patients of this group. 131I-SPECT/CT has a high negative predictive value with regard to the occurrence of radioiodine-positive cervical LNM 5 months after initial therapy. The majority of iodine-positive LNM diagnosed by SPECT/CT at radioablation disappear within 5 months. These findings motivate further research into the value of 131I-SPECT/CT of the neck for predicting recurrence and planning surgical reintervention in DTC. [ABSTRACT FROM AUTHOR]

3-[[sup 123] I]Iodo-α-methyl-L-tyrosine (IMT) is employed clinically as a tracer of amino acid transport in brain tumours using single-photon emission tomography (SPET). This study investigates the role of IMT SPET in the non-invasive histological grading and prognostic evaluation of cerebral gliomas. The files of patients investigated by IMT SPET in our clinic between 1988 and 1996 were evaluated retrospectively. Complete follow-up was available for 58 patients with cerebral gliomas investigated by IMT SPET shortly after tumour diagnosis. Seventeen patients had low-grade gliomas (WHO grade II), 14 had anaplastic gliomas (WHO grade III) and 27 had glioblastomas (WHO grade IV). Thirty-six cases were primary tumours and 22 cases, recurrences. Maximal and mean tumour-to-brain (T/B) ratios of IMT uptake at the first IMT SPET investigation were related to histological grading and survival time. Patients with low-grade gliomas showed significantly longer survival than patients with high-grade (grade III or IV) tumours. Gliomas without contrast enhancement on computed tomography or magnetic resonance imaging scans were associated with longer patient survival than tumours with contrast enhancement. The T/B ratios of IMT SPET showed no differences in relation to histological grading [WHO grade II: 1.73±0.59; WHO grade III: 1.74±0.38; WHO grade IV: 1.59±0.35, (mean±SD, T/B ratios of mean tumour uptake)]. The median survival time of patients with a high T/B ratio on IMT SPET was not significantly different from that of patients with a low T/B ratio (T/B ratio <1.6, 14.8 months; T/B ratio ≥1.6, 13.0 months). Thus, no evidence could be found for a relationship between IMT uptake in cerebral gliomas and either histological grading or survival time. Nevertheless, IMT SPET constitutes a useful method for the detection of primary and recurrent gliomas, determination of tumour extent and individual follow-up. [ABSTRACT FROM AUTHOR]

The synthetic amino acid L-3-[[sup 123]I]iodo-αmethyltyrosine (IMT) is currently under clinical evaluation as a single-photon emission tomography (SPET) tracer of amino acid uptake in brain tumours. So far, dosimetric data in respect of IMT are not available. Therefore we investigated the whole-body distribution of IMT in six patients with cerebral gliomas and the radiation doses were estimated. Whole-body scans were acquired at 1.5, 3 and 5 h after i.v. injection of 370-550 MBq IMT. The bladder was voided prior to each scan and the radioactivity excreted in the urine was measured. Based on the MIRD-11 method and the updated MIRDOSE3, the mean absorbed doses for various organs and the effective dose were calculated from geometric means of the anterior and posterior whole-body scans using seven source organs and the residence time. IMT was predominantly excreted by the kidneys (52.8%±11.5% at 1.5 h p.i., 63.0%±15.7% at 3 h p.i. and 74.6%±9.8% at 5 h p.i.). No organ system other than the urinary tract showed significant retention of the tracer. Early wholebody scans revealed slightly increased tracer uptake in the liver and in the bowel. Highest absorbed doses were found for the urinary bladder wall (0.047 mGy/MBq), the kidneys (0.010 mGy/MBq), the lower large intestinal wall (0.011 mGy/MBq) and the upper large intestinal wall (0.008 mGy/MBq). The effective dose according to ICRP 60 was estimated to be 0.0073 mSv/MBq for adults. This leads to an effective dose of 3.65 mSv in a typical brain SPET study using 500 MBq IMT. The MIRDOSE3 scheme yielded similar results. Thus, in spite of the relatively high tracer dose required for optimal brain scanning, radiation exposure in SPET studies with IMT is in the normal range of routine nuclear medicine investigations. [ABSTRACT FROM AUTHOR]

Abstract. Single-photon emission tomography (SPET) with the amino acid analogue L-3-[[sup 123]I]iodo-alpha-methyl tyrosine (IMT) is helpful in the diagnosis and monitoring of cerebral gliomas. Radiolabelled amino acids seem to reflect tumour infiltration more specifically than conventional methods like magnetic resonance imaging and computed tomography. Automatic tumour delineation based on maximal tumour uptake may cause an overestimation of mean tumour uptake and an underestimation of tumour extension in tumours with circumscribed peaks. The aim of this study was to develop a program for tumour delineation and calculation of mean tumour uptake which takes into account the mean background activity and is thus optimised to the problem of tumour definition in IMT SPET. Using the frequency distribution of pixel intensities of the tomograms a program was developed which automatically detects a reference brain region and draws an isocontour region around the tumour taking into account mean brain radioactivity. Tumour area and tumour/brain ratios were calculated. A three-compartment phantom was simulated to test the program. The program was applied to IMT SPET studies of 20 patients with cerebral gliomas and was compared to the results of manual analysis by three different investigators. Activity ratios and chamber extension of the phantom were correctly calculated by the automatic analysis. A method based on image maxima alone failed to determine chamber... [ABSTRACT FROM AUTHOR]

The immunological mechanisms involved in establishment of herpes simplex virus (HSV) latency were studied in normal and CD4 T-cell depleted C57BL/6J mice following intravaginal infection. During transition from acute to latent ganglionic infection two consecutive processes were observed: first, clearance of infectious virus from the ganglia, and second, reduction of the number of infected ganglia. [ABSTRACT FROM AUTHOR]

Presents a case study of a woman, hospitalized for treatment of a manic and paranoid syndrome, who showed toxic clozapine serum levels during an acute urinary tract infection. Occurrence of toxic clozapine levels due to cytokein-mediated inhibition of cytochrome P450 in intercurrent bacterial infections; Metabolism of clozapine; Finding that prescribed antibiotics, such as trimethroprim, sulfamethoxazol and ampicillin seem not to be responsible for the immense elevation of serum clozapine concentration.