Radiation dose of the lens in trans-sphenoidal pituitary surgery: pros and cons of a conventional setup using fluoroscopic guidance and CT-based neuronavigation

BACKGROUND AND PURPOSE

We determined the radiation dose in patients' lenses during pituitary surgery with either conventional fluoroscopy or CT-guided neuronavigation.

MATERIALS AND METHODS

Thermoluminescent dosimeters (TLD-100H) were attached to the lenses of an anthropomorphic Alderson-Rando head phantom. Simulation of the conventional setup of continuous fluoroscopy (61 kV peak, 2.01 mAs) with collimation and automatic exposure control was used with 1 TLD being removed every 5 seconds, followed by another experiment with 1 being removed every 30 seconds. For CT-guided neuronavigation, a spiral of 3-mm-thick sections without gap was performed (140 kV, 220 mA). Patients' charts (n = 87) were reviewed in terms of radiation exposure and perioperative complications.

RESULTS

Radiation dose is distance-dependent (P < .002), with an exposure-time-dependent linear increase (R(2) = 99.27, P < .0001) close to the primary beam only. The radiation dose of the CT (mean, 39.39 mGy) was fivefold higher compared with the maximal time of 3 minutes (8 mGy) reached in our patients by using the conventional setup. CT offers more detailed 3D anatomy available at any time intraoperatively. Tolerance doses needed to develop cataracts were not reached, and perioperative complications occurred without significant differences (Mann-Whitney U test, P = .39) using either method. Continuous use of fluoroscopy reached the mean value of CT after 14.33 minutes.

CONCLUSION

Neuronavigation provides better anatomic information and avoids repetitive exposure and accumulation to the staff, with the disadvantage of an increased radiation exposure to the patient causing at least no acute harm. Long-term effects are hard to prove but cannot be neglected either.

Number of nitrate groups determines reactivity and potency of organic nitrates: a proof of concept study in ALDH-2-/- mice

BACKGROUND AND PURPOSE

Mitochondrial aldehyde dehydrogenase (ALDH-2) has been shown to provide a pathway for bioactivation of organic nitrates and to be prone to desensitization in response to highly potent, but not to less potent, nitrates. We therefore sought to support the hypothesis that bioactivation by ALDH-2 critically depends on the number of nitrate groups within the nitrovasodilator.

EXPERIMENTAL APPROACH

Nitrates with one (PEMN), two (PEDN; GDN), three (PETriN; glyceryl trinitrate, GTN) and four (pentaerithrityl tetranitrate, PETN) nitrate groups were investigated. Vasodilatory potency was measured in isometric tension studies using isolated aortic segments of wild type (WT) and ALDH-2-/- mice. Activity of the cGMP-dependent kinase-I (reflected by levels of phosphorylated VAsodilator Stimulated Phosphoprotein, P-VASP) was quantified by Western blot analysis, mitochondrial dehydrogenase activity by HPLC. Following incubation of isolated mitochondria with PETN, PETriN-chromophore and PEDN, metabolites were quantified using chemiluminescence nitrogen detection and mass spectrometry.

KEY RESULTS

Compared to WT, vasorelaxation in response to PETN, PETriN and GTN was attenuated about 10fold in ALDH-2-/- mice, identical to WT vessels preincubated with inhibitors of ALDH-2. Reduced vasodilator potency correlated with reduced P-VASP formation and diminished biotransformation of the tetranitrate- and trinitrate-compounds. None of these findings were observed for PEDN, GDN and PEMN.

CONCLUSIONS AND IMPLICATIONS

Our results support the crucial role of ALDH-2 in bioactivating highly reactive nitrates like GTN, PETN and PETriN. ALDH-2-mediated relaxation by organic nitrates therefore depends mainly on the number of nitrate groups. Less potent nitrates like PEDN, GDN and PEMN are apparently biotransformed by other pathways.

Weight gain associated with clozapine, olanzapine and risperidone in children and adolescents

The study was aimed at the evaluation of weight gain associated with atypical antipsychotics and its clinical risk factors in children and adolescents. Weight and body mass index (BMI) of initially hospitalised patients treated with clozapine (n = 15), olanzapine (n = 15), and risperidone (n = 15) were prospectively monitored on a weekly basis for the first 6 weeks. Different clinical risk factors were tested for their association with weight gain in the three groups. All three groups experienced significant weight gain between baseline and endpoint (p < 0.0001). For all weight measures, planned comparisons were all significant between olanzapine vs. clozapine and risperidone, respectively. Average weight gain was significantly higher for the olanzapine group (mean = 4.6 kg, SD = 1.9) than for the risperidone (mean = 2.8 kg, SD = 1.3) and clozapine (mean = 2.5 kg, SD = 2.9) groups. Olanzapine and risperidone, but not clozapine, caused a disproportionately higher weight gain in children and adolescents in comparison to adults.

Forty-two-years later: the outcome of childhood-onset schizophrenia

This paper describes the long-term course of 76 patients who had been consecutively admitted to the Department of Child and Adolescent Psychiatry, Philipps University, between 1920 and 1961 with a suspected diagnosis of childhood-onset schizophrenia. By means of a consensus analysis of available data in accordance with ICD-10 criteria, the diagnosis of schizophrenia was confirmed in only 50% of the original sample (n = 38, childhood-onset schizophrenia group); whereas the rest of the sample were allotted other diagnoses (n = 38, non-schizophrenia group). A follow-up investigation was conducted, interviewing all available patients, if possible, or their first-degree relatives or doctors. In the childhood-onset schizophrenia group, age at onset (mean +/- S.D.) was 12.7 +/- 2.5 (range 5-14) years and age at follow-up was 55.0 +/- 4.8 (range 42-62) years. The outcome of this group was poor. According to the Global Assessment Scale (GAS), only 16% had a good (GAS score 71-100) and 24% had a moderate (GAS score 41-70) outcome. In the 16 childhood-onset schizophrenia patients who could be personally investigated at follow-up, 10 (62.5%) displayed severe or moderate depressive symptoms according to the BPRS depressive score. The death rate (including suicide) was significantly higher in the schizophrenia group (n = 15; 39.5%) than in the non-schizophrenia group (n = 7; 18.4%). A comparison of the life-time diagnoses of the total sample (n = 76) at follow-up with the ICD-10 diagnoses made retrospectively revealed a diagnostic stability in 69 (91%) and a change of diagnosis in 7 (9%) cases, among them 4 who were originally diagnosed as having childhood-onset schizophrenia.

Influence of the matrix on analyte fragmentation in atmospheric pressure MALDI

In this paper, we report the measurement of the degree of analyte fragmentation in AP-MALDI as a function of the matrix and of the laser fluence. The analytes include p-OCH3-benzylpyridinium, three peptides containing the sequence EEPP (which cleave very efficiently at the E-P site), and three deoxynucleosides (dA, dG, and dC), which lose the neutral sugar to give the protonated base. We found that the matrix hardness/softness was consistent when comparing the analytes, with a consensus ranking from hardest to softest: CHCA >> DHB > SA approximately THAP > ATT > HPA. However, the exact ranking can be fluence-dependent, for example between ATT and HPA. Our goal here was to provide the scientific community with a detailed dataset that can be used to compare with theoretical predictions. We tried to correlate the consensus ranking with different matrix properties: sublimation or decomposition temperature (determined using thermogravimetry), analyte initial velocity, and matrix proton affinity. The best correlation was found with the matrix proton affinity.

Wastewater dissolved organic matter: characteristics and sorptive capabilities

An evaluation of the mobility of organic pollutants with wastewater dissolved organic matter (DOM) is essential to better understanding their fate and toxicity to the environment. In this study, DOM from two wastewater treatment plants (in Lachish and Netanya, Israel) were fractionated to hydrophobic-acid (HoA) and hydrophobic-neutral (HoN) fractions. The fractions were characterised and their sorptive capabilities for s-triazine herbicides and polycyclic aromatic hydrocarbons (PAHs) were studied. For all sorbates, binding to the HoN fractions was much higher than to HoA fractions. The high binding coefficients obtained for the studied triazines by the HoN fractions suggested that their sorption is governed by hydrophobic-like interactions rather than H-bonding. The binding coefficients of PAHs measured for the HoN fractions were within the range reported for humic acids and much higher than for the HoA fraction, suggesting that the HoN fraction plays an important role in the overall sorption of these compounds by DOM. Higher sorption coefficients were measured for the Netanya DOM sample containing a higher level of hydrophobic fractions (HoA + HoN) than the Lachish DOM, suggesting that the sorption of hydrophobic organic compounds by DOM is governed by the relative content of these structural substances.

Der Einfluss unterschiedlicher Vaterrassen in praxisüblichen Schweinekreuzungen auf deren Ansatzleistung, Schlachtkörperzusammensetzung sowie Fleisch- und Fettbeschaffenheit

Abstract. Title of the paper: Effect of sire breeds in commercial pig crosses on growth, carcass composition, meat and fat quality 200 weaners from a large field trial in Niedersachsen to test different German and foreign sire breeds for their ability to improve the quality of market products were put at an individual feeding trial at the FAL-Nutrition Institute in Braunschweig. It was the aim of this feeding trial to compare the effects of different fat additions to the diet, sire breeds, sexes and slaughter weights upon growth and usual carcass traits but also upon several additional meat and fat quality traits. The trial was carried out in two blocks with 96 pigs each with the sire breeds Pietrain of the two MHS-genotypes PP (stress susceptible) and NN (stress resistant), Duroc and Hamsphire*Duroc (both NN) as preferrably used in Denmark. As control in both blocks the BHZP-standard boar 65 (PI*HA(NN)) was used. Here only the sire breed effects will be reported. In daily gain and energy conversion only DU-progeny differed significantly from the control (+33g, −1.32 MJ/kg). The tissue dissection showed that PI(PP)-, DU- and HA*DU-progeny had 0.8–1.0% higher bone and respectively lower residual components (lean, fat, tissue). In carcass measurements PI(PP) progeny were the leanest followed by PI(NN), and DU progeny had the smallest loin eye areas and carcass lean contents. This affected the carcass cuts such that PI(PP) progeny had a 1.2 % (= 1.08 kg) higher sum of primal cuts and DU progeny with –0,8% (−400g) below the control were the poorest. In meat quality traits only the heterozygote stress susceptible PI(PP) progeny showed highly significant poorer values than all other crosses, which differed little from each other. This was confirmed by drip losses 2 and 4 days post mortem, which were 1.3–1.6% higher than the control whereas DU progeny were the best with –0.6%. Chemical analysis of a loin sample produced for both Danish sire breeds significantly higher intramuscular fat (+0.36–0.38%) and for PI(PP) progeny with –0.32% the lowest values, but the overall mean reached only 1.3% intramuscular fat. The protein and glycogen contents of loin revieled the expected large deviations of Hamsphire progeny due to the dominant RN- gene (−0.8–1 % protein, +10–14 μmol/g glycogen). All HA-free crossbreds did not differ much. The fatty acid composition of backfat and intramuscular fat showed much smaller differences between sire breeds than between fat supplements to the ration, but Danish sire breeds transmitted higher contents of polyunsaturated and Omega 3 fatty acids than the other sire breeds. Finally, for animals of the second trial also a sensoric test of loin samples was performed at the Federal Meat Research Institute. There subjective scores for tenderness and juiciness as well as grill losses showed significant sire breed differences. But contrary to expectation both Danish sire breeds produced inferior quality in all three traits to PI*HA(NN) control sire groups.