Transformed Testicular Teratoma to Embryonic-Type Neuroectodermal Tumor With Metastasis to Mediastinum.

Testicular teratomas may present in both prepubertal and adult men; however, the prognosis differs greatly between these 2 populations. In children, teratomas (prepubertal type) most often occur before the age of 4, are generally seen in their pure form, and behave in a benign fashion. In adults (postpubertal type), teratomas are usually part of a mixed germ cell tumor, and they have the potential to be found at metastatic sites, especially following chemotherapy for non-teratomatous germ cell tumor. Analyses of metastases from germ cell tumors and teratomas from the same patient have demonstrated a high degree of concordance in the observed genetic abnormalities. In rare cases, testicular teratoma can transform into a malignant germ cell tumor. One such type of transformation is into a primitive neuroectodermal tumor. These tumors are malignant and often metastasize to the retroperitoneum but may also metastasize to other sites. A multimodal treatment approach is needed, including surgery and adjuvant chemotherapy. We describe a rare case of malignant transformation of a testicular teratoma into a primitive neuroectodermal tumor with metastasis to the mediastinum. The patient was treated with radical orchiectomy, retroperitoneal lymph node dissection, and adjuvant vincristine, adriamycin, and cyclofosfamide alternating with ifosfamide and etoposide (VAC/IE therapy).

Hematologic Abnormalities After COVID-19 Infection: A Case of Coombs-Negative Hemolytic Anemia and Thrombocytopenia.

The occurrence of hemolytic anemia in patients with active SARS-CoV-2 infection has been documented in medical literature. While relatively uncommon, there have been instances where this condition presents as a Coombs-negative hemolytic anemia. In this research study, we report a distinctive case of Coombs-negative hemolytic anemia and thrombocytopenia in a patient with a known history of COVID-19 infection. The patient demonstrated a favorable response to treatment involving the administration of steroids and intravenous immunoglobulin (IVIG) therapy. This case adds to the existing body of evidence regarding the hematological manifestations of SARS-CoV-2 infection, highlighting the importance of considering and managing hematological complications in patients with COVID-19.

Multiple Dermatomyofibromas in a Patient with Ehlers-Danlos Syndrome.

Dermatomyofibromas are a rare, benign, acquired neoplasm with less than 150 reported cases worldwide. The etiologic factors that contribute to the development of these lesions are currently unknown. To our knowledge, there have been only six previously reported cases of patients presenting with multiple dermatomyofibromas, and in each of these cases, there were less than ten lesions present. Herein, we describe a patient who developed more than 100 dermatomyofibromas over a period of years, and we argue that the patient's concurrent Ehlers-Danlos syndrome could have contributed to this unique presentation by inducing an increased fibroblast-to-myofibroblast transition.

Going Nuclear with Amino Acids and Proteins: Basic Biochemistry and Molecular Biology Primer for the Technologist.

In recent years, there has been an influx of new tracers into the field of nuclear medicine and molecular imaging. Most of those that have been Food and Drug Administration-approved for clinical imaging exploit various mechanisms of protein biochemistry and molecular biology to bring about their actions, such as amino acid metabolism, protein folding, receptor-ligand interactions, and surface transport mechanisms. In this review, we attempt to paint a clear picture of the basic biochemistry and molecular biology of protein structure, translation, transcription, posttranslational modifications, and protein targeting, in the context of the various radiopharmaceuticals currently used clinically, all in an easy-to-understand language for entry-level technologists in the field. Tracer characteristics, including indications, dosage, injection-to-imaging time, and the logic behind the normal and pathophysiologic biodistribution of these newer molecular tracers, are also discussed.

Internalized Nanoceria Modify the Radiation-Sensitivity Profile of MDA MB231 Breast Carcinoma Cells.

Owing to its unique redox properties, cerium oxide (nanoceria) nanoparticles have been shown to confer either radiosensitization or radioprotection to human cells. We investigated nanoceria's ability to modify cellular health and reactive oxygen species (ROS) at various absorbed doses (Gray) of ionizing radiation in MDA-MB231 breast carcinoma cells. We used transmission electron microscopy to visualize the uptake and compartmental localization of nanoceria within cells at various treatment concentrations. The effects on apoptosis and other cellular health parameters were assessed using confocal fluorescence imaging and flow cytometry without and with various absorbed doses of ionizing radiation, along with intracellular ROS levels. Our results showed that nanoceria were taken up into cells mainly by macropinocytosis and segregated into concentration-dependent large aggregates in macropinosomes. Confocal imaging and flow cytometry data showed an overall decrease in apoptotic cell populations in proportion to increasing nanoparticle concentrations. This increase in cellular health was observed with a corresponding reduction in ROS at all tested absorbed doses. Moreover, this effect appeared pronounced at lower doses compared to unirradiated or untreated populations. In conclusion, internalized nanoceria confers radioprotection with a corresponding decrease in ROS in MDA-MB231 cells, and this property confers significant perils and opportunities when utilized in the context of radiotherapy.

RNA interference microarrays: high-throughput loss-of-function genetics in mammalian cells.

RNA interference (RNAi) is a biological process in which a double-stranded RNA directs the silencing of target genes in a sequence-specific manner. Exogenously delivered or endogenously encoded double-stranded RNAs can enter the RNAi pathway and guide the suppression of transgenes and cellular genes. This technique has emerged as a powerful tool for reverse genetic studies aimed toward the elucidation of gene function in numerous biological models. Two approaches, the use of small interfering RNAs and short hairpin RNAs (shRNAs), have been developed to permit the application of RNAi technology in mammalian cells. Here we describe the use of a shRNA-based live-cell microarray that allows simple, low-cost, high-throughput screening of phenotypes caused by the silencing of specific endogenous genes. This approach is a variation of "reverse transfection" in which mammalian cells are cultured on a microarray slide spotted with different shRNAs in a transfection carrier. Individual cell clusters become transfected with a defined shRNA that directs the inhibition of a particular gene of interest, potentially producing a specific phenotype. We have validated this approach by targeting genes involved in cytokinesis and proteasome-mediated proteolysis.

Representational oligonucleotide microarray analysis: a high-resolution method to detect genome copy number variation.

We have developed a methodology we call ROMA (representational oligonucleotide microarray analysis), for the detection of the genomic aberrations in cancer and normal humans. By arraying oligonucleotide probes designed from the human genome sequence, and hybridizing with "representations" from cancer and normal cells, we detect regions of the genome with altered "copy number." We achieve an average resolution of 30 kb throughout the genome, and resolutions as high as a probe every 15 kb are practical. We illustrate the characteristics of probes on the array and accuracy of measurements obtained using ROMA. Using this methodology, we identify variation between cancer and normal genomes, as well as between normal human genomes. In cancer genomes, we readily detect amplifications and large and small homozygous and hemizygous deletions. Between normal human genomes, we frequently detect large (100 kb to 1 Mb) deletions or duplications. Many of these changes encompass known genes. ROMA will assist in the discovery of genes and markers important in cancer, and the discovery of loci that may be important in inherited predispositions to disease.