Rapidly Fatal Ectopic Adrenocorticotropic Hormone Syndrome in a 9-Year-Old Girl With Ewing Sarcoma.

Background: Ewing sarcoma (ES) with ectopic adrenocorticotropic hormone (ACTH) syndrome (ectopic ACTH) is extremely unusual. This report details the first case in English literature of pediatric ES involving the proximal aspect of the humerus with florid ectopic ACTH. Case Report: A 9-year-old girl presented with mooning of the face and abdominal distension for the past 5 months with an unremarkable history. Her serum cortisol level measured at 8 AM was 42 µg/dL (reference range, 4.3-22.4 µg/dL). Serum ACTH level of 225 pg/mL (reference range, 10-46 pg/mL) suggested ACTH-dependent Cushing syndrome. Her serum cortisol level after the overnight dexamethasone suppression test was 60 µg/dL (reference value, <1.8 µg/dL), suggesting nonsuppressibility. The high-dose dexamethasone suppression test was nonsuppressible, suggesting ectopic ACTH secretion. Findings of magnetic resonance imaging of the brain were normal. Chest x-ray demonstrated a lytic lesion in the left humerus. Magnetic resonance imaging and 3-dimensional computed tomography scans of the left shoulder showed an expansile lesion in the proximal aspect of the humerus. A tru-cut bone biopsy with histopathology and immunostaining revealed clusters of small round cells with a mitotic index of 6/10 hpf to 8/10 hpf. CD99 staining confirmed ES. Ketoconazole was initiated. She received 1 cycle of chemotherapy with cyclophosphamide, vincristine, and doxorubicin and succumbed to the illness 1 week after chemotherapy. Discussion: Ectopic ACTH in the pediatric age group is rare and, coupled with the underlying etiology as ES, makes this case unique. Only 4 cases of ectopic ACTH with ES have been previously reported in the tibia, retroperitoneum, ischiopubic rami, and ribs. This is the first case of ES to have its origin in the humerus with ectopic ACTH. Conclusion: This case highlights an atypical presentation of ectopic ACTH caused by ES arising from the humerus. The etiology of ectopic ACTH as ES was confirmed by chance radiographic evidence of a lytic humerus lesion rather than symptoms.

Antigen levels and antibody titers after DNA vaccination.

DNA vaccination generates strong cellular and humoral immunity in animal models. The mechanisms by which plasmid DNA uptake and expression after intramuscular injection lead to immune responses are not well understood. In particular, the importance of antigen expression levels on subsequent antibody immune responses has not been established. We found that a chemiluminescent assay for alkaline phosphatase allows measurement of antigen levels of secreted alkaline phosphatase (SEAP) in vivo after intramuscular injection of a wide range of plasmid doses. The mice produced antibodies to the alkaline phosphatase reporter gene and both antigen levels and antibody titers were measured over time. We found that the correlation between initial antigen level and antibody response was high (r = 0.74, p < 0.001) and remained high even after accounting for the dose of plasmid injected (r = 0.61, p < 0.001). The correlation between DNA dose and antibody titer was statistically significant (r = 0.53, p < 0.001) but was reduced to almost zero after we accounted for initial antigen levels.

Using differential scanning calorimetry to elucidate metal-protein binding sites in alpha- and gamma-chymotrypsin.

Crystalline alpha-chymotrypsin preparations are contaminated by the post translational variant, gamma-chymotrypsin. The contaminant can account for 5-50 weight percent of the preparation based on thermal analysis. Such contamination can be problematic because this serine protease has both commercial and deactivation model system utility, and the presence of the contaminant may not be detectable by activity assays. Prior work has shown that simple pH gradient elution can separate the two chymotrypsins when loaded to a Cu(2+)-IMAC column; gamma-chymotrypsin eluted first indicating that its interaction with immobilized Cu2+ is weaker. The molecular features that endow these serine proteases with metal affinity has been investigated further by performing differential scanning calorimetry (DSC) studies in the presence and absence of Cu2+, and at different pH values. The dependence of thermostability on pH for fixed metal concentration reveals an interplay between stabilizing and destabilizing metal binding events. The results are consistent with Cu(2+)-chymotrypsin interaction occurring, in part, through binding to a glutamate- or aspartate-containing chelation site. The strength of this site may differ in the two chymotrypsins.

Protein speciation and potential effects on membrane transport and immobilization illustrated by alpha-chymotrypsin.

Protein speciation via physiochemical and biochemical processes presents both challenges and opportunities for membrane applications and research. Different types of speciation and its potential effects are illustrated with the well-known enzyme, alpha-chymotrypsin. This enzyme is capable of self-association and undergoing post-translational modifications. Self-association is shown to alter transport fluxes and also be manipulable. The post-translational modifications generate catalytically-active species that are difficult to detect and different in stability. The presence of different species can conceivably impact on the fabrication, performance, and analysis of immobilized enzyme systems.

Metal-based affinity separation of alpha- and gamma-chymotrypsin and thermal stability analysis of isolates.

Chymotrypsin preparations are contaminated by autolysis products and other post-translational products derived from the zymogen. Some prevalent contaminants are difficult to detect with activity assays and molecular weight separation. However, our differential scanning calorimetry (DSC) studies of alpha-chymotrypsin have revealed that gamma-chymotrypsin is a common contaminant in commercial preparations, and the alpha- and gamma-species differ significantly in thermal stability. Thus, DSC analysis provides a sensitive and rapid means to assess the homogeneity of preparations. Moreover, free metal ion binding studies conducted indicate that the alpha- and gamma-species differ substantially in the number of metal binding sites and metal affinity. Therefore, to attempt to repurify a commercial preparation of alpha-chymotrypsin, a resolubilized sample of alpha-chymotrypsin was subjected to immobilized metal (Cu+2) affinity chromatography with pH elution and the fractions were subjected to DSC analysis. The process successfully removed the majority of the contaminating gamma-chymotrypsin.

A study on immunisation status of children in 1,000 family planning adopted families.

PIP: In a survey, conducted in Tirupati, India, information on the immunization status of the children of a random sample of 1000 family planning acceptors were obtained. The children of all the acceptors were protected against smallpox; however, only 81.5% were protected against polio, 57.2% against tuberculosis, and 10.7% against diphtheria, whooping cough, and tetanus. 863 of the family planning acceptors had adopted temporary family planning methods and 137 had chosen sterilization. 750 of the acceptors had 1-3 children and 250 had 4 or more children. Additional efforts should be made to encourage family planning acceptors to have their children immunized. This would help reduce child morbidity and mortality rates in those families in which the parents have decided to limit family size. Tables showed 1) the number and % of acceptors whose children were immunized for each disease by type of family planning method and 2) the distribution of acceptors by income and by parity.^ieng