Implications at the ocular level of miRNAs modifications induced by SARS-CoV-2 infection.

The coronavirus disease 2019 (COVID-19) pandemic determined the use of different research methods and investigations in the management of this novel infectious disease. The impact and development of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at cellular level is still a challenge and many directions of investigation have been opened, a complex topic that has been explored is the bidirectional interaction between host micro-ribonucleic acids (miRNAs) and viral miRNA. The main point of this study is to analyze the transcriptional modifications induced by the viral infection at ocular level, mediated by miRNAs. It is known that the ocular transmission is a route of infection, and it can cause multiple neuro-ophthalmological manifestations, such as optic nerve dysfunction, eye movement abnormalities, oscillopsia and intracranial hypertension. We have managed to identify more than six miRNAs specifically involved in eye disorders that are strongly dysregulated by the SARS-CoV-2. These miRNAs regulate different pathways, such as the nuclear factor-kappa B (NF-κB) pathway, the expression of complement factor H (CFH) gene, the expression of transforming growth factor-beta (TGF-ß), fibroblast growth factor (FGF) and platelet-derived growth factor (PDGF) genes. In the context of SARS-CoV-2 infection, many more molecular changes at ocular level need to be elucidated to better understanding the COVID-19.

Giant and multiple cardiac papillary fibroelastomas masquerading as acute cerebrovascular events.

Cardiac papillary fibroelastomas are rare benign cardiac tumors. Their clinical significance results from their very high propensity for embolization. We present two such cases, which are rare regarding the size and multiplicity of these tumors.

Clinical, ultrasound and histopathological correlation of clinically N0 neck nodes in patients with cancers of the pharynx and larynx.

BACKGROUND: The presence of metastatic cervical adenopathy is essential for treatment planning and prognosis assessment. Treatment of patients with head and neck cancer with clinically negative cervical lymphadenopathy (N0) remains controversial. Neck palpation, as the method used in tumor, node, metastasis (TNM) staging, has limitations and can provide false negative results in some cases. Lymph node metastases are associated with a reduced survival rate but at the same time, neck dissection for the patient with N0 neck is not without risks or complications. OBJECTIVES: In prospective study, we compared palpation, ultrasonography (US) examination of the neck and histopathological examination in patients with cancers of the pharynx and larynx. PATIENTS, MATERIALS AND METHODS: Forty-six patients with cancers of the pharynx and larynx that presented with a N0 neck were prospectively analyzed. They were divided in two groups: 23 patients operated with an external approach including the control of the lymph node areas, and a second group of 23 patients operated using endoscopy and carbon dioxide (CO2) laser, no neck dissection - "watchful waiting policy". All patients have had a flexible endoscopy of the pharynx and larynx, US of the neck and all received surgical treatment for their primary tumor. Imaging was performed in selected cases. All the removed lymph nodes were sent for histopathology. US was also used as a follow-up method. The US features of the examined lymph nodes were: diameters [longitudinal (L) and transverse (T)]; the ratio of the two diameters (L∕T); shape; lymph node area; central hypodensity; regular∕irregular margins; aspect (homogeneous or not). RESULTS: US has detected 25 lymph nodes in the open surgery group and intraoperatively, we excised 31 (sensitivity of 80.6%). Ten lymph nodes showed metastases, with 100% accuracy of US, which have been confirmed both pathologically and immunohistochemically. US in the second group - patients treated with CO2 laser - detected at four patients 10 cervical lymph nodes that did not presented any malignant features. At recurrence alone, the US confirmed 100% presence of nodes metastases. CONCLUSIONS: US was superior to palpation and this method can be recommended as a diagnostic tool in preoperative assessment of patients without palpable metastasis (N0).

The value of the reprocessing method of paraffin-embedded biopsies for transmission electron microscopy.

Transmission electron microscopy (TEM) implies an elaborate preparation protocol that includes: fixation in glutaraldehyde followed by osmium tetraoxide postfixation, specimen dehydration, infiltration, resin embedding, ultrathin sectioning and staining with heavy metal salts. The aim of TEM is to examine the ultrastructure of specimens in ways that cannot be examined using other equipments or techniques. In some cases, when the requirement for TEM were made after tissue collection, useful information can be obtained from reprocessing the formalin-fixed, wax-embedded tissue used for light microscopy.