Pulmonary Pathology of COVID-19 Following 8 Weeks to 4 Months of Severe Disease: A Report of Three Cases, Including One With Bilateral Lung Transplantation.

Objectives: Current knowledge of the pulmonary pathology of coronavirus disease 2019 (COVID-19) is based largely on postmortem studies. In most, the interval between disease onset and death is relatively short (<1 month). Information regarding lung pathology in patients who survive for longer periods is scant.

Extraneural metastases of primary central nervous system tumors identified by fine needle aspiration: a retrospective analysis.

Objective: Extraneural metastasis (EM) of primary central nervous system (PCNS) neoplasms is rare and signifies a poor clinical outcome. Due to its infrequent occurrence, relatively few reports on the cytomorphology of these neoplasms have been published. We describe a series of 19 cases from 16 patients at a single, large tertiary care center.

Thyroglobulin measurements in fine-needle aspiration cytology of lymph nodes for the detection of metastatic papillary thyroid carcinoma.

Background: Ultrasound-guided fine-needle aspiration (US-FNA) cytology is a commonly used method in the surveillance of suspicious lymph nodes (LNs) in patients with papillary thyroid carcinoma (PTC). The measurement of thyroglobulin (Tg) levels in LNs during FNA has been suggested to improve the diagnosis. In the current study, the use of US-FNA-Tg in LNs that were suspicious for metastatic PTC was investigated.

CD3 in Lewy pathology: does the abnormal recall of neurodevelopmental processes underlie Parkinson's disease.

CD3ζ is a subunit of the CD3 molecule that, until recently, appeared restricted to T cells and natural killer cells. However, experimental studies have demonstrated a role of CD3ζ in dendritic outgrowth in the visual system as well as in synaptic plasticity. Given the increasing evidence for uncharacteristic recapitulation of neurodevelopmental processes in neurodegenerative diseases, in this study, we evaluated brains from subjects with Parkinson's disease and Lewy body dementia for evidence of aberrant CD3 expression.

Ganglioneuroma presenting as a paraesophageal mass lesion diagnosed by endoscopic ultrasound-guided fine needle aspiration cytology: a case report.

Background: Endoscopic ultrasound-guided fine needle aspiration is a well-established modality in detection and diagnosis of mediastinal lesions. Ganglioneuroma is a benign, rare, soft tissue neoplasm arising from sympathetic ganglion cells, and complete surgical resection is considered to be curative. Ganglioneuroma in a surgical specimen is a straightforward diagnosis; however, due to the infrequent occurrence of this entity, diagnosis by fine needle aspiration is more challenging.

Clear cell sarcoma of soft tissue metastatic to the ovaries: a heretofore unreported occurrence.

Clear cell sarcoma of soft tissue (CCSST) is a rare soft tissue neoplasm with marked variable tumor progression and prognosis. Although morphologically similar to malignant melanoma, CCSST can be distinguished by the presence of a t(12; 22)(q13; q12) and/or associated EWSR1-ATF1 chimeric gene. CCSST has an affinity for the extremities and is capable of metastasizing to a wide variety of sites including bone, lung, and lymph nodes and rarely to skin, liver, heart, muscle, and brain.

Metastatic merkel cell carcinoma of the pancreas mimicking primary pancreatic endocrine tumor diagnosed by endoscopic ultrasound-guided fine needle aspiration cytology: a case report.

Background: Merkel cell carcinoma (MCC) is a relatively infrequent, rapidly progressive and often fatal cutaneous malignancy exhibiting neuroendocrine differentiation. It has a penchant for local recurrence and distant metastasis to various sites, including regional lymph nodes, distant skin, lung, liver, testis and other rare organs, such as the pancreas. There are only 4 cases of MCC metastatic to the pancreas reported in the English-language literature, and they were all diagnosed by histology from pancreatic resection.

Composite signet-ring cell/neuroendocrine carcinoma of the stomach with a metastatic neuroendocrine carcinoma component: a better prognosis entity.

Background: Mixed (composite) exocrine-neuroendocrine cell carcinomas are defined as an intimate admixture of neoplastic glandular exocrine and neuroendocrine cell types. Although gastric adenocarcinoma containing a small number of neuroendocrine cells is a relatively frequent occurrence, gastric neoplasms containing equal proportions of both cell types are rare.

Case Presentation: We present a case of composite exocrine (signet-ring cell)-neuroendocrine cell carcinoma, in which the neoplastic signet-ring cell exocrine and neuroendocrine constituents occurred in fairly equivalent amounts, whereas only the neuroendocrine carcinoma portion of the tumor represented the metastatic component.

Lesions of orbitofrontal cortex and basolateral amygdala complex disrupt acquisition of odor-guided discriminations and reversals.

Recent work indicates that both orbitofrontal cortex (OFC) and the basolateral complex of the amygdala (ABL) are involved in processes by which cues are associated with predicted outcomes. To examine the respective roles of these structures in discrimination learning, rats with bilateral sham or neurotoxic lesions of either OFC or ABL were trained on a series of four 2-odor discrimination problems in a thirst-motivated go, no-go task. After acquisition of the series of odor problems, the rats were trained on serial reversals of the final odor problem.

Orbitofrontal lesions in rats impair reversal but not acquisition of go, no-go odor discriminations.

Recent evidence suggests that orbitofrontal cortex lesions cause an inability to withhold inappropriate responses particularly when learned behavior must be modified to reflect changes in the likely outcome or consequence of responding. By this account, orbitofrontal cortex should not be necessary for acquisition of simple discrimination problems, but should be critical for acquiring reversals of those problems. However, previous work in rats has shown orbitofrontal cortex to be critical for withholding responses even in a simple go, no-go discrimination task.