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Motion tracking with finite time sampling causing an associated unknown residual motion between two motion measurements is one of the factors contributing to resolution loss in small animal PET motion correction. The aim of this work is (i) to provide a means to estimate the effect of the finite motion sampling on the spatial resolution of the motion correction reconstructions and (ii) to correct for this residual motion thereby minimizing resolution loss. We calculate a tailored spatially variant deconvolution kernel from the measured motion data which is then used to deconvolve the motion corrected image using a 3D Richardson-Lucy algorithm. A simulation experiment of numerical phantoms as well as a microDerenzo phantom experiment wherein the phantom was manually moved at different speeds was performed to assess the performance of our proposed method. In the motion corrected images of the microDerenzo phantom there was an average rod FWHM differences between the slow and fast motion cases of 9.7%. This difference was reduced to 5.8% after applying the residual motion deconvolution. In awake animal experiments, the proposed method can serve to mitigate the finite sampling factor degrading the spatial resolution as well as the resolution differences between fast-moving and slow-moving animals. Graphical abstract Motion correction of positron emission tomography (PET) scans of moving subjects can be performed by measuring the motion of the subject during the PET scan with an optical tracking camera. The motion tracking data obtained from the tracking camera is then used to correct the PET image reconstructions for motion. Due to finite time sampling of the motion data, the motion corrected reconstructions suffer from loss of spatial resolution. In the proposed method, a spatially variant deconvolution kernel is calculated from the motion tracking data, which is then used to correct the motion-corrected PET reconstructions for the blurring effect of the finite motion sampling through a Richardson-Lucy deconvolution. [ABSTRACT FROM AUTHOR]

Purpose: GANEA2 study was designed to assess accuracy and safety of sentinel lymph node (SLN) after neo-adjuvant chemotherapy (NAC) in breast cancer patients.Methods: Early breast cancer patients treated with NAC were included. Before NAC, patients with cytologically proven node involvement were allocated into the pN1 group, other patient were allocated into the cN0 group. After NAC, pN1 group patients underwent SLN and axillary lymph node dissection (ALND); cN0 group patients underwent SLN and ALND only in case of mapping failure or SLN involvement. The main endpoint was SLN false negative rate (FNR). Secondary endpoints were predictive factors for remaining positive ALND and survival of patients treated with SLN alone.Results: From 2010 to 2014, 957 patients were included. Among the 419 patients from the cN0 group treated with SLN alone, one axillary relapse occurred during the follow-up. Among pN1 group patients, with successful mapping, 103 had a negative SLN. The FNR was 11.9% (95% CI 7.3-17.9%). Multivariate analysis showed that residual breast tumor size after NAC ≥ 5 mm and lympho-vascular invasion remained independent predictors for involved ALND. For patients with initially involved node, with negative SLN after NAC, no lympho-vascular invasion and a remaining breast tumor size 5 mm, the risk of a positive ALND is 3.7% regardless the number of SLN removed.Conclusion: In patients with no initial node involvement, negative SLN after NAC allows to safely avoid an ALND. Residual breast tumor and lympho-vascular invasion after NAC allow identifying patients with initially involved node with a low risk of ALND involvement. [ABSTRACT FROM AUTHOR]

Aromatase inhibitor (AI) therapy for estrogen receptor-positive breast cancer is known to induce or enhance musculoskeletal problems. We have previously reported that loss of grip strength is more pronounced in AI-users with extremes in BMI. We here report results from a larger prospective study. Postmenopausal early breast cancer patients scheduled to start AI or tamoxifen therapy were recruited. A functional assessment grip strength test was performed at baseline, 3, 6, and 12 months of therapy. BMI was assessed, and a rheumatologic questionnaire was completed at each visit. 188 patients on an AI and 104 patients on tamoxifen were enrolled. 74 % of AI-users reported new/worsened musculoskeletal complaints compared with 37 % in the tamoxifen group. This was translated in a larger grip strength decrease in patients experiencing AI-induced pain opposed to patients without new/worsened complaints ( p = 0.0002). 15 % of AI-users discontinued therapy due to musculoskeletal symptoms, who were characterized by a larger grip strength reduction versus adherent patients ( p = 0.0107). Young age ( p = 0.0135), taxane-based chemotherapy ( p = 0.0223), and baseline VAS score >4 ( p = 0.0155) were predictors for AI-related musculoskeletal pain. In addition, a quadratic trend of BMI with grip strength change ( p = 0.0090) and probability of discontinuation was observed ( p = 0.0424). Musculoskeletal events were a substantial problem in AI-treated patients and an important reason for treatment discontinuation. The decrease in grip strength was larger in AI- than in tamoxifen-users, with a more pronounced change in symptomatic patients. The inverse relationship between BMI extremes and grip strength change was confirmed in this large group of AI-patients. [ABSTRACT FROM AUTHOR]

In affluent societies, median age at menarche has dropped to below 13 years. Younger age at menarche is associated with earlier sexual activity. To avoid unintended teenage pregnancies, barriers to contraception provision must be kept low, i.e. availability without prescription or through a low-threshold prescription system, low-cost options and long-term prescriptions or easy refills. Since many adolescents are (over)concerned about side effects, these should be addressed. A gynaecological examination prior to prescription is no longer recommended. All effective reversible contraceptive methods are available to adolescents: user-based hormonal contraceptives, trimonthly depot medroxyprogesterone acetate (DMPA), and long-acting reversible contraception (LARC). User-based hormonal contraceptives carry a small absolute risk of venous thromboembolism (~4 per 10,000 patient-years), but the risk is more than tenfold higher among young women with an inherited clotting defect. DMPA reduces bone mineral accumulation, but this is a reversible effect; the metabolic risks, including weight gain and insulin resistance, appear to be greater. LARC, including intrauterine contraceptive devices and the progestogen-containing implant, is gaining popularity among teenagers; abnormal bleeding is the main side effect. Any effective contraceptive should preferably be combined with consistent condom use to prevent sexually transmitted infections ("the double Dutch"). [ABSTRACT FROM AUTHOR]

Background: Telerobotic-assisted laparoscopic attempts to provide technological solutions to the inherent limitations of traditional laparoscopic surgery. The aim of this study is to report the first experience of two teams concerning telerobotic-assisted laparoscopic hysterectomy for benign and malignant pathologies.Methods: This study included 14 patients at the University Hospital Saint Pierre of Brussels (Belgium) and 16 patients at the Cancer Center of Nancy (France) from September 1999 to July 2003.Results: The indications for surgery were uterine malignant diseases in 12 cases (stade I) (41%), and benign pathologies of the uterus in 18 cases (59%). Five postoperative complications (17%) occurred, none related to the robotic system.Conclusion: Robotic surgery can be safely performed in gynecologic and gynecologic-oncologic surgery with no increase in complication rates. A significant advance is represented by the surgeon's ergonomic improvement. [ABSTRACT FROM AUTHOR]

Oral contraceptives (OC) modulate the risk for developing cardiovascular (CV) diseases. The aim of this study was to determine whether the use of third-generation OC has an impact on markers of CV disease in genetically identical women. We performed an intrapair comparison in 27 monozygotic twin pairs, one of whom was taking third-generation OC, whereas the other was not using OC. Biometric parameters were ascertained and conventional and 24-h ambulatory blood pressure (BP) was recorded. A fasting blood sample was taken for the measurement of glucose, insulin, proinsulin, lipids, and insulin-like growth factor binding protein-1 (IGFBP-1). Insulin resistance and b-cell function were calculated by homeostasis model assessment (HOMA). A 24-h urine sample for cortisol was obtained. Third-generation OC use increased 24-h ambulatory systolic and diastolic BP by 5.2 and 3.9 mmHg, respectively (both P =0.0003). There was no effect on glucose, insulin and proinsulin levels, and on HOMA parameters, but the IGFBP-1 levels were markedly raised (P =0.0009). The lipid profile showed a 34% increase in triglyceride levels (P<0.0001), but also a 7% increase in HDL-cholesterol levels (P =0.037). Use of third-generation OC impacts on CV disease markers in young-adult genetically identical women. Some changes are beneficial (increased HDL-cholesterol), whereas others may be deleterious (increased BP and triglyceride levels) or have unknown effects at this time (increased IGFBP-1 levels). [ABSTRACT FROM AUTHOR]

Vitamin D (D) deficiency during human pregnancy appears to disturb fetal growth and mineralization, but fetal development is normal in D-deficient rats and vitamin D receptor gene-ablated mice. We used the guinea pig model to investigate maternal and fetal effects of D deficiency. Pregnant (Pr) and nonpregnant (NPr) animals were fed a D-replete (+D) or D-deficient diet (?D) for 8 weeks. We further studied whether the effects of a ?D diet are reversed by continuous 1,25(OH)2D3 infusion (?D+1,25) and/or by a lactose-, Ca- and P-enriched D-deficient diet (?D+Ca/P). Bone analyses included histomorphometry of the proximal tibiae, dual-energy X-ray absorptiometry (DXA), and quantitative computed tomography (QCT) of the femora. Depletion of 25(OH)D3 and 1,25(OH)2D3 levels and the D-deficiency syndrome were more severe in pregnant animals. Indeed, Pr/?D but not NPr/?D guinea pigs were hypophosphatemic, and showed robust increases in growth plate width and osteoid surface and thickness; in addition, bone mineral density on DXA was lower in Pr/?D animals only, which was exclusively in cortical bone on QCT. Bone phenotype was partly normalized in Pr/?D+1,25 and Pr/?D+Ca/P animals. Compared with +D fetuses, ?D fetuses had very low or undetectable 25(OH)D3 and 1,25(OH)2D3, were hypercalcemic and hypophosphatemic, and had lower osteocalcin levels. In addition, body weight and total body bone mineral content were 10–15% lower; histomorphometry showed hypertrophic chondrocyte zone expansion and hyperosteoidosis. 1,25(OH)2D3 levels were restored in ?D+1,25 fetuses, and the phenotype was partially corrected. Similarly, the fetal +D phenotype was rescued in large part in ?D+Ca/P fetuses, despite undetectable circulating 25(OH)D3 and 1,25(OH)2D3. We conclude that pregnancy markedly exacerbates D deficiency, and that augmenting Ca and P intake overrides the deleterious effects of D deficiency on fetal development. [ABSTRACT FROM AUTHOR]

The HELLP syndrome (hemolysis, elevated liver enzymes, low platelets) is a pathological entity in obstetrics that is related to preeclampsia. Recognition and early treatment are mandatory, because of the high fetal and maternal morbidity and fetal mortality rates. This report features the CT and MRI findings in two patients with HELLP syndrome, upper abdominal pain, and severe liver cell dysfunction. Despite the extensive hepatic abnormalities seen on CT and MRI studies, both patients recovered fully after delivery. The role of imaging studies for diagnosis and treatment planning in the clinical setting of HELLP syndrome is discussed. [ABSTRACT FROM AUTHOR]

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Copyright of Insectes Sociaux 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.)

Copyright of Insectes Sociaux 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.)

Copyright of Insectes Sociaux 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.)

Scintillators for the detection of slow neutrons were obtained by pressing mixtures of HBO and ZnS(Ag) phosphor into thin, slightly transparent disks. In order to obtain optimal conditions, we studied the influence of mixing-ratio, thickness and pressure on detection efficiency. The scintillator obtained in this way was compared with a commercial NE 400 slow neutron boronpolyester detector. [ABSTRACT FROM AUTHOR]

The specific heat of two ferrites with respective chemical composition Mn Zn, Fe O( a ≈ 0.38) and Ni Zn Fe O( a ≈ 0.50) has been measured with a Nernst adiabatic calorimeter in the temperature range 20°C-350°C. Associated with the ferrimagnetic transition an enhanced specific heat, due to the magnetic contribution, is observed, having a maximum at the Curie-point (172°C and 308.5°C respectively). The results of the measurements are tabulated and discussed. [ABSTRACT FROM AUTHOR]