Characterization of neurological morbidity associated with thyroid antibodies: Hashimoto's encephalopathy and beyond.

BACKGROUND: Hashimoto's Encephalopathy (HE) manifests with various neurologic symptoms associated with elevated thyroglobulin (TG) and/or thyroperoxidase (TPO) antibodies. Some patients with thyroid antibodies exhibit neurological presentations not consistent with HE. This study aims to characterize the spectrum of neurological morbidity in patients with thyroid antibodies. METHODS: We reviewed all patients tested for TG or TPO antibodies from 2010 to 2019. Patients tested for thyroid antibodies as part of a neurological workup for new symptoms were classified into the following categories: patients meeting full criteria for HE, patients with other neuroimmunological disorders, patients with unexplained neurological symptoms not fully meeting HE criteria, and patients with incidental non neuroimmunological disorders. RESULTS: There were 2717 patients with positive thyroid antibodies in the dataset including 227 patients (78% female, age 54 ± 19 years) who met inclusion criteria. Twelve patients (5%) met HE criteria, 30 (13%) had other neuroimmunological disorders, 32 (14%) had unexplained neurological symptoms, and 153 (67.4%) had incidental disorders. In addition to cognitive dysfunction, seizures, movement disorders, motor weakness, and psychosis, HE patients were also more likely to have cerebellar dysfunction, language impairment, and sensory deficits. They were more likely to carry a Hashimoto's thyroiditis diagnosis and had higher titers of thyroid antibodies. They all had a robust response to steroids. CONCLUSION: The neurological spectrum of HE may be wider than previously reported, including frequent cerebellar, sensory, and language dysfunction. A subgroup of thyroid antibody positive patients with unexplained neurological symptoms may represent further expansion of thyroid antibody-related neurological disorders.

The effect of stress on learning in surgical skill acquisition.

BACKGROUND: An excessive level of stress and anxiety in medical education can have a negative impact on learning. In particular, the interaction between attending surgeons and trainees in the operating room could induce stress on trainees that is counterproductive, especially if the teaching style or feedback is unduly harsh or critical. AIM: To characterize the effects of stress resulting from attending-trainee interaction during surgical skill acquisition. METHODS: Forty medical students learned to perform the FLS pattern-cutting task for the first time in one of four scenarios. In the control condition, no mentor was present. In the three experimental conditions, participants were observed, encouraged, or criticized by an expert surgeon. RESULTS: Task performance, as well as physiological and subjective indicators of stress, were measured. Taking both speed and accuracy into account, participants who were criticized performed the worst on the task, and those who were encouraged performed best. Physiological and subjective measures indicated that the criticized participants experienced the highest level of stress and anxiety. CONCLUSION: Even though providing constructive criticism to trainees is inevitable during the course of teaching, an exceedingly critical and negative mentoring style by attending physicians could be detrimental to trainees' acquisition of surgical skills.

Deoxynucleoside salvage facilitates DNA repair during ribonucleotide reductase blockade in human cervical cancers.

Cells generate 2'-deoxyribonucleoside triphosphates (dNTPs) for both replication and repair of damaged DNA predominantly through de novo reduction of intracellular ribonucleotides by ribonucleotide reductase (RNR). Cells can also salvage deoxynucleosides by deoxycytidine kinase/thymidine kinase 1 in the cytosol or by deoxyguanosine kinase/thymidine kinase 2 in mitochondria. In this study we investigated whether the salvage dNTP supply pathway facilitates DNA damage repair, promoting cell survival, when pharmacological inhibition of RNR by 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, NSC no. 663249) impairs the de novo pathway. Human cervical cancer cells were subjected to radiation with or without 3-AP under medium deoxynucleoside concentrations of 0, 0.05, 0.5 and 5.0 µM. Efficacy of DNA damage repair was assessed by γ-H2AX flow cytometry and focus counts, by single cell electrophoresis (Comet assay), and by caspase 3 cleavage assay as a marker of treatment-induced apoptosis. Cell survival was assessed by colony formation. We found that deoxyribonucleotide salvage facilitates DNA repair during RNR inhibition by 3-AP and that salvage reduces the radiochemosensitivity of human cervical cancer cells.