Recent Publications by CFE Educators

Spinal cord transplants of embryonic cortical GABAergic progenitor cells derived from the medial ganglionic eminence (MGE) can reverse mechanical hypersensitivity in the mouse models of peripheral nerve injury- and paclitaxel-induced neuropathic pain. Here, we used electrophysiology, immunohistochemistry, and electron microscopy to examine the extent to which MGE cells integrate into host circuitry and recapitulate endogenous inhibitory circuits. Whether the transplants were performed before or after nerve injury, the MGE cells developed into mature neurons and exhibited firing patterns characteristic of subpopulations of cortical and spinal cord inhibitory interneurons. Conversely, the transplanted cells preserved cortical morphological and neurochemical properties. We also observed a robust anatomical and functional synaptic integration of the transplanted cells into host circuitry in both injured and uninjured animals. The MGE cells were activated by primary afferents, including TRPV1-expressing nociceptors, and formed GABAergic, bicuculline-sensitive, synapses onto host neurons. Unexpectedly, MGE cells transplanted before injury prevented the development of mechanical hypersensitivity. Together, our findings provide direct confirmation of an extensive, functional synaptic integration of MGE cells into host spinal cord circuits. This integration underlies normalization of the dorsal horn inhibitory tone after injury and may be responsible for the prophylactic effect of preinjury transplants.

SIGNIFICANCE STATEMENT

Spinal cord transplants of embryonic cortical GABAergic interneuron progenitors from the medial ganglionic eminence (MGE), can overcome the mechanical hypersensitivity produced in different neuropathic pain models in adult mice. Here, we examined the properties of transplanted MGE cells and the extent to which they integrate into spinal cord circuitry. Using electrophysiology, immunohistochemistry, and electron microscopy, we demonstrate that MGE cells, whether transplanted before or after nerve injury, develop into inhibitory neurons, are activated by nociceptive primary afferents, and form GABA-A-mediated inhibitory synapses with the host. Unexpectedly, cells transplanted into naive spinal cord prevented the development of nerve-injury-induced mechanical hypersensitivity. These results illustrate the remarkable plasticity of adult spinal cord and the potential of cell-based therapies against neuropathic pain.

OBJECTIVES/HYPOTHESIS

To characterize clinical, imaging, and sialendoscopy findings in patients with chronic parotitis and multiple parotid calcifications.

STUDY DESIGN

Retrospective review.

METHODS

Clinical history, radiographic images and reports, lab tests, and operative reports were reviewed for adult patients with chronic parotitis and multiple parotid calcifications who underwent parotid sialendoscopy.

RESULTS

Thirteen of 133 (10%) patients undergoing parotid sialendoscopy for chronic sialadenitis had more than one calcification in the region of the parotid gland. Seven patients (54%) were diagnosed with immune-mediated disease from autoimmune parotitis (positive Sjögren's antibodies or antinuclear antibodies) or human immunodeficiency virus (HIV) disease. The six patients (46%) who did not have an immune-mediated disorder had most calcifications located anterior or along the masseter muscle. Eight of 13 patients (61%) had at least one calculus found in the parotid duct on sialendoscopy. Four patients (38%) had multiple punctate calcifications within the parotid gland, all of whom had either autoimmune parotitis or HIV. None of the proximal or punctate parotid calcifications posterior to the masseter were visualized on sialendoscopy.

CONCLUSIONS

Chronic parotitis in conjunction with multiple parotid calcifications is uncommon and was identified in 10% of our cohort. We contrast two classifications of parotid calcifications: 1) intraductal stones that cause recurrent duct obstruction and are often located within the main parotid duct along or anterior to the masseter and 2) punctate intraparenchymal parotid gland calcifications that are not visualized on sialendoscopy and may represent underlying inflammatory disease.

LEVEL OF EVIDENCE

4 Laryngoscope, 127:1565-1570, 2017.

BACKGROUND

There is a paucity of literature to direct physicians in the prescribing of immunomodulators for patients with severe atopic dermatitis (AD).

OBJECTIVE

To survey systemic agent prescribing practices for severe childhood AD among clinicians in the United States and Canada.

METHODS

The TREatment of severe Atopic dermatitis in children Taskforce (TREAT), US&CANADA, a project of the Pediatric Dermatology Research Alliance (PeDRA), developed an online multiple-response survey to assess clinical practice, gather demographic information and details of systemic agent selection, and identify barriers to their use in patients with recalcitrant pediatric AD.

RESULTS

In total, 133 of 290 members (45.9%) of the Society for Pediatric Dermatology completed the survey, and 115 of 133 (86.5%) used systemic treatment for severe pediatric AD. First-line drugs of choice were cyclosporine (45.2%), methotrexate (29.6%), and mycophenolate mofetil (13.0%). The most commonly used second-line agents were methotrexate (31.3%) and mycophenolate mofetil (30.4%); azathioprine was the most commonly cited third-line agent. The main factors that discouraged use of systemic agents were side-effect profiles (82.6%) and perceived risks of long-term toxicity (81.7%).

LIMITATIONS

Investigation of the sequence of systemic medications or combination systemic therapy was limited. Recall bias may have affected the results.

CONCLUSION

Great variation exists in prescribing practices among American and Canadian physicians using systemic agents for treatment of pediatric AD.

BACKGROUND

The recently published 2015 American Thyroid Association guidelines recognize lobectomy as a viable alternative for low-risk cancers and advise more conservative use of radioactive iodine. Some factors indicating adjuvant treatment with radioactive iodine (and therefore completion total thyroidectomy), however, only can be found upon pathologic investigation.

METHODS

We performed a retrospective analysis including patients with American Thyroid Association low- and low-to-intermediate risk well-differentiated thyroid cancer 1-4 cm. We evaluated how often radioactive iodine would be indicated and compared this with our historic rate. A subanalysis was performed to determine the rate of completion total thyroidectomy necessary, based on the indications for adjuvant radioactive iodine therapy.

RESULTS

A total of 394/1,000 (39.4%) patients were included for final analysis. Adjuvant radioactive iodine would have been favored in 101/394 (25.6%) of patients, which is 2.5 times less than was given in our historic cohort. Completion total thyroidectomy to enable adjuvant radioactive iodine would have been recommended in 29/149 (19.5%) patients preoperatively eligible for lobectomy.

CONCLUSION

Despite the tightened regulations for radioactive iodine, about 20% of patients with apparently "low-risk" well-differentiated thyroid cancer who are eligible for lobectomy may need completion total thyroidectomy because of pathologic findings for which radioactive iodine use is listed as considered or favored by the current guidelines.

TGF-β promotes excessive collagen deposition in fibrotic diseases such as idiopathic pulmonary fibrosis (IPF). The amino acid composition of collagen is unique due to its high (33%) glycine content. Here, we report that TGF-β induces expression of glycolytic genes and increases glycolytic flux. TGF-β also induces the expression of the enzymes of the de novo serine synthesis pathway (phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH)) and de novo glycine synthesis (serine hydroxymethyltransferase 2 (SHMT2)). Studies in fibroblasts with genetic attenuation of PHGDH or SHMT2 and pharmacologic inhibition of PHGDH showed that these enzymes are required for collagen synthesis. Furthermore, metabolic labeling experiments demonstrated carbon from glucose incorporated into collagen. Lungs from humans with IPF demonstrated increased expression of PHGDH and SHMT2. These results indicate that the de novo serine synthesis pathway is necessary for TGF-β-induced collagen production and suggest that this pathway may be a therapeutic target for treatment of fibrotic diseases including IPF.

BACKGROUND

The management of low-risk micropapillary thyroid cancer 1 cm in size has come into question, because recent data have shown that nonoperative active surveillance of micropapillary thyroid cancer is a viable alternative to hemithyroidectomy. We conducted a cost-effectiveness analysis to help decide between observation versus operation.

METHODS

We constructed Markov models for active surveillance and hemithyroidectomy. The reference case was a 40-year-old patient with recently diagnosed, low-risk micropapillary thyroid cancer. Costs and health utilities were determined using extensive literature review. The willingness-to-pay threshold was set at $100,000/quality-adjusted life year gained. Deterministic and probabilistic sensitivity analyses were performed to account for uncertainty in the model's variables.

RESULTS

Active surveillance is dominant (less expensive and more quality-adjusted life years) for a health utility 0.01 below that for disease-free, posthemithyroidectomy state, or for a remaining life expectancy of 2 years. For a utility difference ≥0.02, the incremental cost-effectiveness ratio (the ratio of the difference in costs between active surveillance and hemithyroidectomy divided by the difference in quality-adjusted life years) for hemithyroidectomy is $100,000/QALY gained and thus cost-effective. For a utility difference of 0.11-the reference case scenario-the incremental cost-effectiveness ratio for hemithyroidectomy is $4,437/quality-adjusted life year gained.

CONCLUSION

The cost-effectiveness of hemithyroidectomy is highly dependent on patient disutility associated with active surveillance. In patients who would associate nonoperative management with at least a modest decrement in quality of life, hemithyroidectomy is cost-effective.