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The detection of prostate cancer lesions by PET imaging of the prostate-specific membrane antigen (PSMA) has gained highest clinical impact during the last years. 68Ga-labelled Glu-urea-Lys(Ahx)-HBED-CC ([68Ga]Ga-PSMA-HBED-CC) represents a successful novel PSMA inhibitor radiotracer which has recently demonstrated its suitability in individual first-in-man studies. The radiometal chelator HBED-CC used in this molecule represents a rather rarely used acyclic complexing agent with chemical characteristics favourably influencing the biological functionality of the PSMA inhibitor. The simple replacement of HBED-CC by the prominent radiometal chelator DOTA was shown to dramatically reduce the in vivo imaging quality of the respective 68Ga-labelled PSMA-targeted tracer proving that HBED-CC contributes intrinsically to the PSMA binding of the Glu-urea-Lys(Ahx) pharmacophore. Owing to the obvious growing clinical impact, this work aims to reflect the properties of HBED-CC as acyclic radiometal chelator and presents novel preclinical data and relevant aspects of the radiopharmaceutical production process of [68Ga]Ga-PSMA-HBED-CC. [ABSTRACT FROM AUTHOR]

The article discusses social stratification within the peasant communities of late medieval England, with particular focus given to the work of Marxist historian Rodney Hilton. The author utilizes manorial court records as a means to investigate peasants' everyday lives and whether or not the peasantry was divided or a solid social class. She investigates the various levels of rent extracted from peasants by their lords and notes how agricultural communities were influenced by urbanization. The impact of inheritance customs on peasant stratification is also examined.

LC-MS/MS is widely utilized today for quantification of vitamin D in biological fluids. Mass spectrometric assays for vitamin D require very careful method optimization for precise and interference-free, accurate analyses however. Here, we explore chemical derivatization and matrix-assisted laser desorption/ionization (MALDI) as a rapid alternative for quantitative measurement of 25-hydroxyvitamin D3 in human serum, and compare it to results from LC-MS/MS. The method implemented an automated imaging step of each MALDI spot, to locate areas of high intensity, avoid sweet spot phenomena, and thus improve precision. There was no statistically significant difference in vitamin D quantification between the MALDI-MS/MS and LC-MS/MS: mean ± standard deviation for MALDI-MS—29.4 ± 10.3 ng/mL—versus LC-MS/MS—30.3 ± 11.2 ng/mL (P = 0.128)—for the sum of the 25-hydroxyvitamin D epimers. The MALDI-based assay avoided time-consuming chromatographic separation steps and was thus much faster than the LC-MS/MS assay. It also consumed less sample, required no organic solvents, and was readily automated. In this proof-of-concept study, MALDI-MS readily demonstrated its potential for mass spectrometric quantification of vitamin D compounds in biological fluids.ᅟ [ABSTRACT FROM AUTHOR]

Vitamin D measurements in biological fluids by mass spectrometry are challenging at very low concentration levels. As a result, chemical derivatization is often employed to enhance the ionization properties of low abundant vitamin D compounds. Cookson-type reagents such as 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) or similar derivatives work well but require careful, water-free experimental conditions, as traces of water inactivate the reagent and inhibit or stop the derivatization reactions, thus making quantitative measurements in aqueous samples impossible. We describe a novel electrospray liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for determining 25-hydroxyvitamin D 3 (25(OH)D 3 ) directly in aqueous cellular systems using a new derivatization reagent, the ionic liquid 12-(maleimidyl)dodecyl-tri-n-butylphosphonium bromide (MDBP). The proof-of-concept for the MDBP assay was demonstrated by measuring the levels of 25(OH)D 3 in four different human cell types, namely T cells, helper T cells, B cells, and macrophages. In addition to the ability to determine the levels of 25(OH)D 3 directly in aqueous samples, the cellular integrity was maintained in our application. We show the time-dependent uptake of 25(OH)D 3 into the investigated cells to demonstrate the applicability of the new label. Furthermore, the MDBP derivatization technique may be equally useful in imaging mass spectrometry, where it could be used for response enhancements of spatially localized vitamin D metabolites on wet tissue surfaces, without destroying the integrity of the tissue surface. Graphical Abstract MDBP labelling of 25-hydroxyvitamin D in the extracellular space.

While the biological function of the 3α epimer of 25-hydroxyvitamin D 3 (25(OH)D 3 ) remains unknown, its presence needs to be accurately captured and separated from the main 3β epimer, to avoid positive bias in vitamin D status analyses. Several recent LC-MS/MS assays for 25(OH)D 3 successfully separate the 3α and 3β epimers by chromatography. Unfortunately, none of the existing LC-MS/MS assays, which utilize dried blood spots (DBS) as sampling/storage vessels, is able to quantify the individual epimers. DBS are often used for analysis of infant blood, however, and these samples are particularly likely to contain significant levels of interfering 3α epimer. Furthermore, proper calibration of DBS samples is much more difficult to achieve than for liquid serum or plasma samples. We addressed this important issue by creating an artificial vitamin D-free whole blood for calibration and then quantified 3α- and 3β-25(OH)D 3 levels from DBS. After chemical derivatization, the vitamin D epimers were separated on a PFP column and concentrations determined by electrospray ionization LC-MS/MS on a triple quadrupole mass spectrometer. Calibration with artificial whole blood showed improved precision over standard addition (7.6 versus 31.5% RSD for 3β-25(OH)D 3 ). The limits of quantification for 3β-25(OH)D 3 and for 3α-25(OH)D 3 were 1.0 and 0.1ng/mL, respectively. Excellent intra/interday precisions between 2.1 and 2.2% CV (intra) and 4.4-5.3% CV (inter) were established for 3β-25(OH)D 3 and 3α-25(OH)D 3 . For 3β-25(OH)D 3 , only small concentration-independent bias and deviation of <3.3ng/mL were seen between serum LC-MS/MS and DBS-LC-MS/MS measurements; analyses of 3α-25(OH)D 3 showed deviations of <0.8ng/mL in all experiments., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this study, 98 families with 101 mutations were analyzed in depth in which a mutation had been observed at one of the four loci D3S1358, FGA, ACTBP2, and VWA. To determine the origin (male/female) of the mutation, five to seven polymorphic flanking markers were selected for each locus concerned and used to construct family-specific haplotypes. Additionally, all alleles of the STR system concerned were sequenced. With this duplicate approach, it was possible to identify the mutated structure and/or mutation event in the vast majority of cases. The ratio of one-step to two-step mutations was 100:1. The ratio of paternal to maternal mutations was 76:8. The ratio of gains to losses was 47:50. Also, the mutation rates in two systems, ACTBP2 and VWA, were clearly higher than those given in the literature.

This study assessed the clinical and radiological outcomes after treatment of scaphoid non-union of the proximal third by non-vascularised bone grafts and stabilisation by Mini-Herbert Screws from a dorsal approach. Thirty-one patients, one woman and 30 men, were reviewed retrospectively at a mean of 42 (12-77) months. All patients received pre- and postoperative CT scans to assess bone union. In addition to demographic data, the range of motion, grip strength, DASH score, Krimmer score, Mayo wrist score and radiological parameters (carpal height, scapholunate and radiolunate angles) were recorded. Bone union was achieved in 21 patients. The average DASH score in patients with bone union was 12 and that in patients with persistent non-union it was 30. No progression into carpal collapse or increase of scapholunate angles was detected. Our study demonstrates that acceptable union rates can be achieved with non-vascularised bone grafts, and this technique compares favourably with other reports in the literature.

Background: Stress fractures are frequent injuries among athletes. In vitro, decreases in pH stimulate osteoclasts and inhibit osteoblasts. We hypothesized that exercise-induced lactacidosis stimulates osteoclasts and reduces osteoblast activity in vivo., Methods: A total of 32 volunteers (MA, male athletes; MCo, male controls; female athletes; and female controls) performed three 60-min cycle ergometer tests at 75%, 95% and 110% of their individual anaerobic threshold (IAT). Blood was taken before and at 3 and 24 h after exercise. Osteocalcin (OC), pro-collagen type I N-terminal peptide (PINP), C-terminal telopeptides of collagen I (CTx) and tartrate-resistant acid phosphatase (TRAP) were measured., Results: At 75% and 95% IAT, pH did not change. At 110% IAT, pH decreased in MA by 0.08 units (p=0.041) and in MCo by 0.03 units (p=0.017). The pH results were substantiated by circulating lactate concentrations. The bone resorption markers TRAP and CTx were not consistently modified by any of the exercise tests. Exercise at 75% decreased OC and PINP in all groups. Exercise at 95% and 110% did not induce homogeneous effects., Conclusions: Anaerobic exercise does not systemically affect bone turnover, suggesting that exercise-induced acidosis is not involved in the pathogenesis of stress fractures.

In the course of routine genotyping of forensic reference samples by multiplex PCR, an allelic drop-out due to mutations in the primer binding regions of the highly polymorphic STR marker ACTBP2 was observed in 17 samples. The variation rate was estimated to be 0.0014 (95% confidence interval: 0.0006-0.003). The most frequently found mutation was an G to A transition in the reverse primer binding region which was present in 14 out of 17 cases. To overcome the problem we have added a modified reverse primer to different multiplex kits that led to the correct genotype.