Phase equilibria in the MnO-Mn2O3-FeO-Fe2O3-Sb2O3-Sb2O5 System in Air at 1200℃

Using the methods of X-ray phase and X-ray Densitometric analysis, the phase equilibria between oxides of manganese, iron and antimony have been investigated in an air atmosphere at temperatures up to 1250? in an air mosphere at normal pressure. The phase diagram of the system at 1200? was built MnO-Mn2O3-FeO-Fe2O-Sb2O3-Sb2O5. A new phase was found Mn12-2x,sup>2+Fe2x2+Sb3+Sb55+O26(0?x?1), with edge compositions FeMn5Sb3O13 and Mn6Sb3O3 (a=8.5003?0.0025Å; b=8.0064?0.0025Å; c=11.5779?0.0025Å; Z = 3; ?obs. = 5.7 g/cm3; ?calc = 5.6991 g/cm3). The phase exists in the temperature range 1180-1230oC and can be obtained by quenching, but always with a large admixture of Mn2Sb2O7 and spinel Mn112+Mn133+Sb93+O44.The reason for this behavior is that air molecules have different temperatures, as a result of which the phase composition of the reaction mixture cannot be strictly related to one temperature, and different phases can be stable at different temperatures.

Semiautomatic VWF Multimer Densitometric Analysis: Validation of the Clinical Accuracy and Clinical Implications in Von Willebrand Disease

Introduction Von Willebrand factor (VWF) multimer analysis is an essential tool in the diagnosis and classification of von Willebrand disease (VWD). Current visual VWF multimer analysis is observer dependent, time consuming and is inaccurate in detecting subtle changes in multimer patterns. Therefore, recent studies have investigated VWF multimer quantification using semiautomatic densitometric analysis. The accuracy of VWF multimer densitometric analysis in clinical practice needs further investigation before it can be widely used. The aim of the study was to validate the accuracy of VWF multimer densitometric analysis in clinical practice. Additionally, we aimed to identify patient characteristics associated with VWF multimer densitometry outcomes in type 1 and type 2 VWD patients, and we investigated whether subtle differences in VWF multimer pattern are associated with the bleeding phenotype of VWD patients. Methods We included patients from the nationwide Willebrand in the Netherlands (WiN) study. The inclusion criteria of the WiN study were a personal hemorrhagic diathesis or family history of VWD, and historically lowest VWF antigen (VWF:Ag), VWF activity (measured with the monoclonal antibody assay: VWF:Ab) or VWF collagen binding (VWF:CB) ≤0.30 IU/mL or FVIII activity (FVIII:C) ≤0.40 IU/mL in case of type 2N VWD. At inclusion in the WiN study, blood was drawn and patients filled in an extensive questionnaire containing a self-administered Tosetto bleeding score (BS). For multimer analysis, citrated blood samples were separated on 0.9% agarose gel and visualized by Western blotting. We used IMAGEJ for densitometric analysis. The five smallest bands on densitometric images were defined as small multimers, next five bands were defined as medium multimers and the remaining bands were defined as large multimers. Medium-large VWF multimer index was calculated by dividing the patient's multimer ratio (intensity of the medium and large multimers divided by the total intensity of all multimers) by the multimer ratio of a normal control in the same western blot. If no multimers could be detected, the multimer index was set as 0. Results We included 561 VWD patients: 328 type 1, 211 type 2 and 21 type 3 patients. The median age was 44 [IQR 29-58] and 351 patients (62.7%) were female (Table 1). Figure 1 illustrates typical densitometric outcomes of a type 1 VWD patient with normal VWF multimers (A) and a type 2A patient with reduced high-molecular-weight (HMW) VWF multimers (B). Medium-large VWF multimer index was 1.06 [0.99-1.12] in type 1 and 0.53 [0.29-0.89] in type 2 and 0.00 [0.00-0.00] in type 3 VWD. Medium-large VWF multimer index was in patients visually classified as normal, reduced and absent HMW VWF multimers, respectively 1.07 [1.02-1.12], 0.84 [0.71-0.91] and 0.31 [0.20-0.44] (p<0.001, Figure 2A). With visual examination as gold standard, medium-large VWF multimer index had a very good accuracy in distinguishing normal VWF multimers from reduced HMW VWF multimers (AUC: 0.96 (0.94-0.98) p<0.001, Figure 2B). It could also accurately distinguish reduced HMW VWF multimers from absence of HMW multimers, with an AUC of 0.95 (0.92-0.97, p<0.001), and type 2A and 2B from type 2M and 2N (AUC: 0.96 (0.94-0.99), p<0.001, Figure 2C and 2D). From VWF activity measurements, medium-large VWF multimer index was strongest correlated with VWF:CB (ρ=0.79, p<0.001). From the ratio of the various functional VWF measurements (divided by VWF:Ag), the strongest correlation was again found for VWF:CB/VWF:Ag ratio (ρ=0.80, p<0.001). In type 1 VWD, an increased clearance of VWF (defined as VWFpropeptide/VWF:Ag ratio ≥2.2) was independently associated with lower medium-large VWF multimer index (β=-0.10 (-0.14; -0.07), p<0.001). Also, type 1 VWD patients with a VWF gene variant had relatively lower medium-large VWF multimer index compared to type 1 patients without a VWF variant, respectively 1.03 [0.95-1.10] vs 1.08 [1.04-1.12] (p<0.001). In the total population, higher medium-large VWF multimer index was associated with a lower bleeding score: β=-4.6 (-7.2; -2.0), p=0.001, adjusted for age, sex, blood group and type of VWD. Conclusion Semiautomatic densitometric analysis of VWF multimers has an excellent accuracy in clinical practice, and may have an additional value in providing a better understanding of the clinical features such as the bleeding phenotype of VWD patients. Disclosures Atiq: CSL Behring: Research Funding; SOBI: Other: travel grant. Boender:SOBI: Current Employment; CSL Behring: Research Funding. Cnossen:Bayer: Research Funding; Novo Nordisk: Research Funding; Nordic Pharma: Research Funding; Sobi: Research Funding; Takeda: Research Funding; CSL behring: Research Funding; Pfizer: Research Funding; Shire: Research Funding; Baxter: Research Funding. van der Bom:Bayer: Speakers Bureau. Fijnvandraat:SOBI: Research Funding; NovoNordisk: Consultancy; Grifols: Consultancy; Takeda: Consultancy; Roche: Consultancy; CSL Behring: Research Funding; NovoNordisk: Research Funding. Van Galen:Bayer: Research Funding; Takeda: Speakers Bureau; CSL Behring: Research Funding. Laros-Van Gorkom:Baxter: Other: Educational grant; CSL Behring: Other: Educational grant. Meijer:Bayer: Research Funding; Sanquin: Research Funding; Pfizer: Research Funding; Bayer: Speakers Bureau; Sanquin: Speakers Bureau; Boehringer Ingelheim: Speakers Bureau; BMS: Speakers Bureau; Aspen: Speakers Bureau; Uniqure: Consultancy. Eikenboom:CSL Behring: Research Funding; Roche: Other: Teacher on educational activities. Leebeek:Roche: Other: DSMB member for a study; SOBI: Other: Travel grant; Novo Nordisk: Consultancy; Shire/Takeda: Consultancy; Uniqure: Consultancy; Shire/Takeda: Research Funding; CSL Behring: Research Funding.

Alteration of mucins in the submandibular gland during aging in mice

ObjectiveMucins are large glycosylated glycoproteins that are produced in the salivary glands, and their changes may contribute to the development of xerostomia due to aging and the accompanying deterioration of oral hygiene. This study aimed to characterize the changes in the mucins produced in submandibular gland (SMG) during the aging process.MethodsSMG mucins derived from mice of each age were separated using supported molecular matrix electrophoresis (SMME). Subsequently, the membranes were stained with AB or blotted with MAL-II lectin. The SMME membranes stained with AB were subjected to densitometric analysis and glycan analysis. The detailed structures of O-glycan were investigated by MS/MS spectra.ResultsThe SMG of mice secreted three mucins with different glycan profiles: age-specific mucin, youth-specific mucin, and a mucin expressed throughout life, and the expression patterns of these mucins change during aging. Additionally, age-specific mucin began to be detected at about 12 months of age. A mucin expressed throughout life and age-specific mucin had the same mass of major glycans but different structures.Furthermore, the proportion of mucin glycan species expressed throughout life changed during the aging process, and aging tended to decrease the proportion of fucosylated glycans and increase the proportion of sialoglycans.ConclusionThere are three secretory mucins with different glycan profiles in the SMG of mice, and their expression patterns change according to the period of the aging process. The proportion of glycan species of mucin expressed throughout life also changes during the aging process.HighlightsThree secreted mucins with different glycan profiles are detected in SMG using SMME.Each mucin has its own peak production age during the aging process.Age-specific mucin begins to be detected at about 12 months of age.Same mass of major glycans but different structures in mucins expressed throughout life vs. age-specific mucins.Proportion of mucin glycan species expressed throughout life changes during aging.