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Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive neurostimulation technique for the treatment of various neurological and psychiatric disorders. To investigate the working mechanism of this treatment approach, we designed a small-animal coil for dedicated use in rats and we combined this neurostimulation method with small-animal positron emission tomography (microPET or µPET) to quantify regional 2-deoxy-2-(18F)fluoro-D-glucose ([18F]-FDG) uptake in the rat brain, elicited by a low- (1 Hz) and a high- (50 Hz) frequency paradigm. Rats (n = 6) were injected with 1 mCi of [18F]-FDG 10 min after the start of 30 min of stimulation (1 Hz, 50 Hz or sham), followed by a 20-min µPET image acquisition. Voxel-based statistical parametric mapping (SPM) image analysis of 1-Hz and 50-Hz versus sham stimulation was performed. For both the 1-Hz and 50-Hz paradigms we found a large [18F]-FDG hypermetabolic cluster (2.208 mm³ and 2.616 mm³, resp.) (analysis of variance (ANOVA), p < 0.05) located in the dentate gyrus complemented with an additional [18F]-FDG hypermetabolic cluster (ANOVA, p < 0.05) located in the entorhinal cortex (2.216 mm³) for the 50-Hz stimulation. The effect on [18F]-FDG metabolism was 2.9 ± 0.8% at 1 Hz and 2.5 ± 0.8% at 50 Hz for the dentate gyrus clusters and 3.3 ± 0.5% for the additional cluster in the entorhinal cortex at 50 Hz. The maximal (4.19 vs. 2.58) and averaged (2.87 vs. 2.21) T-values are higher for 50 Hz versus 1 Hz. This experimental study demonstrates the feasibility to combine µPET imaging in rats stimulated with rTMS using a custom-made small-animal magnetic stimulation setup to quantify changes in the cerebral [18F]-FDG uptake as a measure for neuronal activity. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Because of the extensive variability in paracetamol clearance in young women, published data were pooled with newly collected observations in search of covariates of paracetamol pharmacokinetics (PK) within this specific population. SUBJECTS AND METHODS: PK estimates and clinical characteristics [pregnant, weight, exposure to oral contraceptives (OC)] in young women following IV loading dose (2 g paracetamol) were pooled, using a non-compartmental linear disposition model in individual time-concentration profiles. Data were reported by median and range. Rank correlation was used to link clearance (l/h) to weight, Mann Whitney U test to compare clearance (l/h.m-2) between subgroups (pregnant, OC exposure). Finally, a multiple regression model with clearance (l/h) in all women and all non-pregnant women was performed. RESULTS: Based on 73 paracetamol PK estimates, a 8-fold variability in clearance (range 7.1-62.2 l/h) was documented, in part explained by a correlation (r2=0.36) between clearance (l/h) and weight. Clearance (l/h and l/h.m-2) and distribution volume (l) at delivery (n=36) were higher compared to non-pregnant observations. In nonpregnant women, women on OC (n=20) had a higher paracetamol clearance (l/h.m-2) compared to women (n=17) not on OC (p = 0.023).Weight (p = 0.0043) and pregnancy (p = 0.02) were independent variables (r=0.56) of paracetamol clearance (l/h). In non-pregnant women, weight (p = 0.009) and OC exposure (p = 0.03) were independent variables (r=0.51). CONCLUSIONS:Weight, pregnancy and OC result in higher clearance of IV paracetamol in young women. Besides compound specific relevance, these findings also unveil covariates of drug metabolism in young women. [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: To evaluate the levels of insulin-like growth factor-binding protein-1 (IGFBP-1) in cervicovaginal secretions before and after midtrimester amniocentesis and relate to clinical outcome. Methods: 100 consecutive amniocentesis procedures were studied. We measured the IGFBP-1 concentration by radioimmunoassay in a cervicovaginal specimen before and after mid-trimester amniocentesis. The post-amniocentesis occurrence of vaginal loss of fluid or blood and abdominal pain was assessed by questionnaire. Results: In 6 cases there was a 100-fold increase in IGFBP-1 levels after amniocentesis. Loss of fluid per vaginam occurred in 4 (67%) of these pregnancies, compared to 3.2% of pregnancies without significant surge (p < 0.0001). In addition, post-procedural abdominal pain was more common among women with increased IGFBP-1 levels after amniocentesis (50 vs. 14%, p = 0.05). Two (33%) of the 6 patients with increased IGFBP-1 after amniocentesis delivered prior to 37 weeks as a result of spontaneous preterm labor and/or preterm ruptured membranes, compared to 7 (7%) in the group without surge in IGFBP-1 (p = 0.09). Conclusion: Increased post-procedure IGFBP-1 levels are after mid-trimester amniocenteses are related to procedure-related complications like abdominal pain and subsequent amniotic fluid leakage. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Radiofrequency (RF) is a method of in situ destruction of liver tumor. Biliary complications are bile ducts stenosis or biliary abcess. The aim of this work was to study consequences of liver RF on bile ducts. Methods: A porcine model of biliary lesions was created using radiofrequency ablation liver. Twenty-two pigs were used for the study. The RF RITA 1500 generator (RITA Medical Systems, Mountain View, Calif., USA) was used for all experiments. The needle was positioned under sonographic control in liver parenchyma beside bile ducts. Two lesions were performed in left liver. Four groups of 5 pigs were treated. The pigs were sacrificed 1 or 3 weeks after the procedure. Pringle maneuver was utilized in half of the RF procedures. An ex vivo cholangiogram was obtained by direct injection into the main bile duct. Samples of RF lesions of liver parenchyma near and at a distance from the RF lesions were taken for pathological studies. Results: Radiological lesions were biliary stenosis, with or without upstream bile duct dilatation, or complete interruption of the bile duct, or extravasation of the radiological contrast agent. Histological lesions of bile ducts were observed near RF lesions and at distance of the RF lesions when a Pringle maneuver was used or when the liver was removed after 3 weeks. Conclusions: RF ablation in contact of the intrahepatic bile duct induced biliary lesions. Therefore, it is required to stay away from the bile duct or to protect it when performing RF ablation. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to examine the regulation of fetal serum concentrations of insulin (C-peptide), insulin-like growth factor-I, insulin-like growth factor-II, and insulin-like growth factor binding protein-1, which are growth-regulating factors in the fetus, in monozygotic and dizygotic twin pairs.Study Design: Cord serum samples were collected from 110 twin pairs and compared with 178 nonsibling singleton pairs with the same gestational age. Five twin pairs were excluded from the statistical analyses because of severe intrauterine growth restriction and placental abnormalities in one. Zygosity was assigned by histologic examination of the placenta and by a questionnaire sent to the mother when the twins were > or = 6 months old. Analyses included the calculation of correlation coefficients, between-pair variation, and univariate genetic analysis.Results: Cord serum C-peptide concentrations were highly correlated in monozygotic (r = 0.94) and dizygotic twins (r = 0.79) but not in singleton pairs (r = -0.05); the between-pair variation was also smaller in twins than in singletons. Genetic analysis demonstrated a large contribution of the common environment to the variance in C-peptide concentrations (80%) and a smaller genetic contribution (12%). Insulin-like growth factor-I concentrations were better correlated in monozygotic (r = 0.82) than in dizygotic twins (r = 0.42), with a smaller between-pair variation in the former group (22% +/- 4% vs 51% +/- 5%). Univariate genetic analysis indicated that insulin-like growth factor-I levels were regulated predominantly by genetic mechanisms (93% in boys and 77% in girls). The regulation of insulin-like growth factor-II was more complex, with a gender-specific genetic contribution (50% for both sexes combined, 63% for girls but only 5% for boys). Insulin-like growth factor binding protein-1 was regulated by genetic mechanisms (41%) and the common environment (32%) but also by the specific or unique environment of each fetus (27%). In all five twins with intrauterine growth restriction of one member insulin-like growth factor binding protein-1 concentrations were markedly higher in the growth-restricted fetus.Conclusions: Insulin secretion in twin fetuses is determined primarily by their common, probably maternal, environment, whereas insulin-like growth factor-I production is predominantly genetically regulated. Insulin-like growth factor-II and insulin-like growth factor binding protein-1 are regulated by both genetic and environmental factors. Of these growth-regulating factors, insulin-like growth factor binding protein-1 appears to be the best marker of intrauterine growth restriction in the individual case. [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]