Parathyroid adenoma presenting with spontaneous cervical and anterior mediastinal hemorrhage: A case report

RATIONALE

Spontaneous anterior cervical or mediastinal hemorrhage is a rare presentation of parathyroid adenoma.

PATIENT CONCERNS

A 69-year-old woman presented with neck hematoma and dysphagia and was found to have a soft tissue mass adjacent to her thyroid gland as seen on MRI and neck ultrasound.

DIAGNOSIS

Laboratory testing demonstrated elevated calcium and parathyroid hormone supporting diagnosis of parathyroid adenoma.

INTERVENTIONS

She underwent right inferior parathyroidectomy and en bloc right hemithyroidectomy due to significant fibrosis.

OUTCOMES

Pathology confirmed hypercellular parathyroid and normal thyroid tissue. Postoperatively, patient's calcium and parathyroid hormone levels had normalized.

LESSONS

In conclusion, imaging may not always be specific in identifying the source of neck hematoma and so laboratory studies should be done to rule out parathyroid adenoma as the underlying etiology.

Adipocyte differentiation-related protein in human skeletal muscle: relationship to insulin sensitivity

OBJECTIVE

To determine whether adipocyte differentiation-related protein (ADRP), a lipid droplet-associated protein that binds to and sequesters intracellular fatty acids, is 1) expressed in human skeletal muscle and 2) differentially regulated in human skeletal muscle obtained from obese non-diabetic (OND) and obese diabetic (OD) subjects.

RESEARCH METHODS AND PROCEDURES

Ten OND subjects and 15 OD subjects underwent a weight loss or pharmacological intervention program to improve insulin sensitivity. Anthropometric data, hemoglobin A(1C), fasting glucose, lipids, and glucose disposal rate were determined at baseline and at completion of studies. Biopsies of the vastus lateralis muscle (SkM) were obtained in the fasting state from OND and OD subjects. Protein expression was determined by Western blotting.

RESULTS

ADRP was highly expressed in SkM from OND (4.4 +/- 1.54 AU/10 microg, protein, n = 10) and OD (5.02 +/- 1.33 AU/10 microg, n = 12) subjects. OND subjects undergoing weight loss had decreased triglyceride levels and improved insulin action. SkM ADRP content increased with weight loss from 5.14 +/- 2.15 AU/10 microg to 9.92 +/- 1.57 AU/10 microg (p < 0.025). OD subjects were treated with either troglitazone or metformin, together with glyburide, for 3 to 4 months. Both treatments attained similar levels of glycemic control. OD subjects with lower baseline ADRP content (2.85 +/- 1.07 AU/10 microg, n = 6) displayed up-regulation of ADRP expression (to 9.27 +/- 2.76 AU/10 microg, p < 0.025).

DISCUSSION

ADRP is the predominant lipid droplet-associated protein in SkM, and low ADRP expression is up-regulated in circumstances of improved glucose tolerance. Up-regulation of ADRP may act to sequester fatty acids as triglycerides in discrete lipid droplets that could protect muscle from the detrimental effects of fatty acids on insulin action and glucose tolerance.

A colourimetric dye assay to detect anti-viral activity of interferons: sensitivity for measuring cellular responsiveness to interferons

Colourimetric assays which rely on the conversion of metabolic dyes are becoming increasingly used for measuring cell proliferation and cytotoxicity. We developed a method for measuring cellular responsiveness to interferons based on the property of interferons to induce cell defenses to virus-mediated killing. The assay has several advantages over previous assays for measuring anti-viral activity and efficiently detected cytoprotective responses to human interferon of five human melanoma cell lines infected with Semliki Forest virus. The melanoma cell lines showed a varying cytoprotective response to interferons alpha 2, alpha 4, beta and gamma, in agreement with the results of previous assays for measuring melanoma cell responsiveness to interferons based upon the inhibition of cell growth (1).