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NaClO 3 is achiral in solution. If crystallization is performed under a static set-up, it is recognized that the stochastic nucleation probability results in a racemic mixture of the conglomerate. In this paper, we report a reexamination of the crystallization of NaClO 3 from static solution in petri dishes that was conducted over a number of years and is based on the count and analysis of several thousand d- vs. l-NaClO 3 crystals. Remarkably, instead of an expected nearly 50/50 coin-tossing situation for the d/l crystal frequency, in most of our experiments a statistically significant bias in favor of d- over l-NaClO 3 crystals was found. The experiments also showed that the NaClO 3 system was relatively insensitive regarding the intentional addition of a variety of optically active agents. Only in some cases, the persisting d-bias observed in the unseeded experiments slightly increased upon the presence of such additives. Nevertheless, experiments in plastic petri dishes or in presence of fungal spores were able to reverse this bias. A literature survey shows that mainly d-directed non-stochastic behavior in the NaClO 3 system has been previously observed in other laboratory settings and by the application of different crystallization techniques. So far, the kind of chiral influence that could be at the origin of the observed bias remains unknown. After the examination of several possible chiral influences of physical, chemical and biological origin, we carefully consider the presence of bio-contaminants as most likely for the cause of this effect., (© 2019 Wiley Periodicals, Inc.)

Background: Missed oesophageal cancer (MEC) at upper gastrointestinal endoscopy (UGE) is poorly documented., Objective: The objectives of this study were: (1) to assess the rate, predictors and survival of MEC; (2) to compare MEC and non-MEC tumours., Methods: This was a retrospective cohort study conducted at four tertiary centres. Oesophageal cancers (ECs) diagnosed between 2008 and 2015 were included. Patients with a premalignant condition (Barrett, achalasia), prior diagnosis of EC or oesophagogastric junction tumour of gastric origin were excluded. MEC was defined as EC detected within 36 months after negative UGE., Results: 123,395 UGEs were performed during the study period, with 502 ECs being diagnosed (0.4%). A total of 391 ECs were finally included. Overall MEC rate was 6.4% (95% confidence intervals (CI): 4.4-9.3%). The interval between negative and diagnostic UGE was less than 2 years in 84% of the cases. Multivariate analysis showed that a negative endoscopy was associated with proton pump inhibitor (PPI) therapy and less experienced endoscopists. MEC was smaller than non-MEC at diagnosis (25 versus 40 mm, p  = 0.021), more often flat or depressed ( p  = 0.013) and less frequently diagnosed as metastatic disease ( p  = 0.013). Overall 2-year survival rate was similar for MEC (20%) and non-MEC (24.1%) ( p  = 0.95)., Conclusions: MEC accounted for 6.4% of all ECs and was associated with poor survival. High-quality UGE and awareness of MEC may help to reduce its incidence.

Anosmin-1 participates in the development of the olfactory and GnRH systems. Defects in this protein are responsible for both the anosmia and the hypogonadotrophic hypogonadism found in Kallmann's syndrome patients. Sporadically, these patients also manifest some neurological symptoms that are not explained in terms of the developmental defects in the olfactory system. We describe the pattern of Anosmin-1 expression in the central nervous system during rat development using a novel antibody raised against Anosmin-1 (Anos1). The areas with Anos1-stained neurons and glial cells were classified into three groups: (1) areas with immunoreactivity from embryonic day 16 to postnatal day (P) 15; (2) areas with Anosmin-1 expression only at postnatal development; (3) nuclei with immunoreactivity only at P15. Our data show that Anos1 immunoreactivity is detected in projecting neurons and interneurons within areas of the brain that may be affected in patients with Kallmann's syndrome that develop both the principal as well as sporadic symptoms.

One of the problems associated with the modern biomaterials used in prostheses is osteolysis, which, although its exact origin is unknown, has been associated with wear particles. Osteoblasts seem to participate directly in this phenomenon. This paper investigates in vitro cellular response to the wear particles from the metal substrate and ceramic covering (alpha-alumina) of a new titanium yttrium aluminum alloy, MA 956, that has been proposed as a biomaterial because of its exceptional mechanical and electrochemical properties. The effect of different sizes (10 and 80 microm) of MA 956 and alpha-alumina particles on osteoblast function was studied in primary human bone cell cultures. Cells were harvested from trabecular bone fragments obtained during knee arthroplasty. Osteoblastic cell response to the particles was measured by assaying C-terminal type I procollagen (PICP), alkaline phosphatase, and osteocalcin secretion, with and without 1.25(OH)(2)D(3) stimulation, in the cell-conditioned medium. Both sizes of MA 956 and alpha-alumina particles decreased PICP secretion in nonstimulated osteoblastic cells, but this secretion was not affected in the cultures stimulated with 1.25(OH)(2)D(3). Only the 10 microm alpha-alumina particles inhibited alkaline phosphatase activity in 1.25(OH)(2)D(3)-stimulated and nonstimulated cultures. The rise in osteocalcin levels after 1.25(OH)(2)D(3) stimulation was lower in the presence of the 10 microm MA 956 particles than in the presence of alpha-alumina particles. Although both materials seem to have directly affected in vitro osteoblastic cell function, the increase in osteocalcin levels after 1.25(OH)(2)D(3) stimulation was lower after exposure to MA 956 particles than the increase observed after exposure to alpha-alumina particles. Therefore, it does not seem that osteocalcin stimulated bone resorption, suggesting that MA 956 would be less likely to provoke osteolysis., (Copyright 2000 John Wiley & Sons, Inc.)