Well-differentiated chrondrosarcoma in a cynomolgus macaque (Macaca fascicularis).

A cynomolgus macaque presented with an osteolytic lesion of the left femur. Histopathology was consistent with well-differentiated chondrosarcoma. No metastasis was found in chest radiographs out to 12 months. This case suggests survival out to 1 year without metastasis following amputation may be possible in NHPs with this condition.

Maternal risk factors and neonatal outcomes in placental abruption among patients with equal access to health care.

INTRODUCTION: Placental abruption complicates 1% of pregnancies, and is associated with significant morbidity and mortality. The objective was to examine risk factors and outcomes in pregnancies complicated by abruption in a health care system with equal access to care. METHODS: This was a retrospective cohort study of all deliveries at Walter Reed National Military Medical Center (WRNMMC) between 1 January 2014 and 1 June 2017. The primary outcome was maternal factors that influenced abruption. The secondary outcome evaluated the neonatal outcomes after abruption. RESULTS: A total of 4351 patients delivered at WRNMMC and met the inclusion criteria. 52 patients (1.2%) had a pathology confirmed abruption. There was an association with smoking (p < .05; OR 4.25) and African American race (p = .005). Neonatal variables demonstrated an association between abruption and gestational age at delivery, low birth weight, Apgar scores, NICU admissions, and fetal demise all with p < .005. CONCLUSIONS: Our results demonstrate an association between both smoking and African American race with placental abruption. Unlike previous studies, there were no barriers to access to care. Further, there was no association with age, hypertension, diabetes, autoimmune disease, or trauma. Results did reaffirm an association between abruption and preterm birth, low birth weight, lower Apgars, NICU admissions, and fetal demise.PrécisIn a medical system with no barriers to access to care, maternal risk factors and neonatal outcomes associated with placental abruptions were investigated in over 4300 deliveries.

Comprehensive study on critical micellar concentrations of SDS in acetonitrile-water solvents.

The CMC is one of the fundamental characteristics of surfactants and its determination is crucial for detail understanding of micelles formation. In this study the CMC of SDS in presence of ACN was determined by two independent experimental techniques, capillary electrophoresis and fluorescence correlation spectroscopy (FCS). Yet, studies of SDS micellization in solutions containing ACN as organic modifier are sparse and inconsistent in literature. The measurements were performed for various ACN contents in the range of 0-50% v/v. At ACN contents of up to 10% v/v the CMC is lower when compared to the aqueous solution, while increasing ACN content causes a significant increase of the CMC. Formation of micelles was observed up to ACN concentrations of 35% v/v, which is in contrast to most of the reports in literature. Based on the results of the FCS experiments, we were able to confirm that presence of ACN causes a gradual increase of the size of the micelles with increasing concentration of SDS. Simultaneously, we proved that the classical conductivity approach for the determination of the CMC does not yield reliable results in the presence of higher content of an organic modifier such as ACN.

Investigation of the enantiomerization barriers of the phthalimidone derivatives EM12 and lenalidomide by dynamic electrokinetic chromatography.

The phthalimidone derivatives EM12 and lenalidomide, which are both structurally related to thalidomide, are highly interesting drugs and very recently lenalidomide attracted great attention as an antitumor and immune-modulating drug in the therapy for multiple myeloma. EM12 and lenalidomide are chiral, and the stereogenic carbon C-3 in the piperidine-2,6-dione moiety of these phthalimidone derivatives is prone to interconversion due to keto-enol tautomerization. The knowledge of the enantiomerization barrier is mandatory for pharmacokinetic studies and to develop a tailored therapy using the enantiopure or racemic drug. Here, we used dynamic EKC in combination with direct-calculation methods to determine the enantiomerization barriers of EM12 and lenalidomide. The separations of the enantiomers of EM12 and lenalidomide were performed in 50 mM aqueous disodium hydrogen phosphate buffer at pH 8 and 50 mM aqueous sodium tetraborate buffer at pH 9.3, respectively, using 20 mg/mL heptakis-(2,3-diacetyl-6-sulfato)-ß-CD as a chiral additive. Enantiomerization of the compounds during the electrokinetic chromatographic separation resulted in pronounced plateau formation between the well-separated enantiomers. Peak form analysis of the experimentally obtained interconversion profiles yielded the enantiomerization rate constants k1 of EM12 and lenalidomide as well as the kinetic activation parameters ΔG(‡), ΔH(‡‡), and ΔS(‡) of enantiomerization by the evaluation of temperature-dependent measurements. The enantiomerization barrier ΔG(‡) was determined to be 98.3 ± 1.0 kJ/mol; the activation parameters ΔH(‡) = 46.1 ± 2.4 kJ/mol and ΔS(‡) = -170 ± 61 J/(K·mol) for EM12 and ΔG(‡) = 91.5 ± 1.0 kJ/mol, ΔH(‡) = 62.4 ± 5.4 kJ/mol, and ΔS(‡) = -98 ± 7 J/(K·mol) for lenalidomide. These findings were corroborated by density functional theory calculations at the B3LYP/3-21G level of theory of the ground state and intermediates considering an enantiomerization pathway via a keto-enol tautomerism.