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Graphical abstract, Highlights • RCC is the most common type of renal cancer. • RCC is capable of passing through the renal vein into the IVC. • Surgical resection requiring cardiopulmonary bypass is currently the only curative treatment. • Metastatic RCC tumor spread into the heart is a poor long-term prognostic factor.

A 69-year-old woman presented with worsening dyspnoea for a month. She had a history of moderately differentiated non-mucinous appendiceal adenocarcinoma, diagnosed 10 months prior based on pathology from an emergent appendectomy for acute appendicitis. Mesenteric margins had been indeterminate but

Serratia marcescens is an aerobic, Gram-negative bacillus first identified in 1819 (Yeung et al. 2018). S. marcescens infective endocarditis is extremely rare accounting for only 0.14% of all cases (Phadke and Jacob 2016, Hadano et al. 2012, Nikolakopoulos et al. 2019). We present the case of a 33-year-old male with a past medical history of Hodgkin lymphoma, nonischemic cardiomyopathy ejection fraction of 25–30%, severe aortic stenosis, hepatitis C, and active intravenous (IV) drug abuse who was admitted following a motor vehicle accident. Approximately 10 days into his admission, he developed a 39.5 degree Celsius fever, which prompted collection of blood cultures. These cultures were positive (2 out of 2) for S. marcescens for which he was treated with intravenous cefepime. Soon after this diagnosis, patient developed a complete AV block. Given the instability of the patient, he required emergent placement of a temporary pacing wire. Transesophageal echocardiogram was ordered and revealed an aortic root abscess. Given the comorbidities and active IV drug use, conservative management was pursued. Although rare, trends suggest that this pathogen may be on the rise. Further research is needed to better understand how to effectively manage this pathogen.

First isolated in 1943, Stenotrophomonas maltophilia (S. maltophilia) has historically been of little significance as it was considered a pathogen of low virulence noted to rarely infect immunocompromised hosts. However, over the last 30 years the prevalence of infection caused by the organism has increased significantly. Bacterial endocarditis from S. maltophilia remains exceedingly rare with only a small number of reported cases in the literature. This case involves a 27 year old male with sickle cell anemia with an indwelling right subclavian port who presented to the emergency department with myalgias, fever, and chills. His initial blood cultures grew Gram negative rods later identified as S. maltophilia. Transthoracic echocardiogram showed a mass in the right atrium. Transesophageal echocardiogram revealed a large C-shaped mass with attachment to the tricuspid annulus, mitral valve wall, and port tip in right atrium. The patient underwent sternotomy with removal of the vegetation to prevent embolization. He was treated with intravenous ciprofloxacin and oral trimethoprim/sulfamethoxazole to complete a full 6 weeks of therapy, making a full recovery. This report will further explore the unique presentation of this pathogen along with its epidemiology, resistance mechanisms, risk factors for infection, diagnosis, and appropriate antimicrobial treatment. Keywords: S. Maltophilia, Endocarditis

Heart valve replacement with a mechanical valve requires lifelong anticoagulation. Guidelines currently recommend using a vitamin K antagonist (VKA) such as warfarin. Given the teratogenic effects of VKAs, it is often favorable to switch to heparin-derived therapies in pregnant patients since they do not cross the placenta. However, these therapies are known to be less effective anticoagulants subjecting the pregnant patient to a higher chance of a thrombotic event. Guidelines currently recommend pregnant women requiring more than 5 mg a day of warfarin be switched to alternative therapy during the first trimester. This case report highlights a patient who was switched to alternative therapy during her first pregnancy and suffered a devastating cerebrovascular accident (CVA). Further complicating her situation was during a subsequent pregnancy; this patient continued warfarin use during the first trimester and experienced multiple transient ischemic attacks (TIAs). This case highlights the increased risk of thrombotic events in pregnant patients with mechanical valves. It also highlights the difficulty of providing appropriate anticoagulation for the pregnant patient who has experienced thrombotic events on multiple anticoagulants.

The term “mycotic aneurysm” was first used by Osler in 1882 to describe a mushroom-shaped aneurysm in subacute bacterial endocarditis. Mycotic aneurysms account for only 2.6% of all aneurysms of the aorta. Rarer still are anaerobic infections secondary to organisms such as Clostridium septicum, which results in emphysematous aortitis. The vast majority of emphysematous aortic infections occur as a result of instrumentation; however, in this case we present an infection de novo. A 75-year-old male presented with a 2-week history of progressive fatigue and chest pain that then developed into constitutional symptoms. Chest radiograph demonstrated an obvious widened mediastinum. CT angiogram of his chest then confirmed this finding as well as significant periaortic gas and focal outpouching. Numerous diverticuli with inflammatory changes consistent with diverticulitis was observed on CT abdomen. Blood cultures returned positive for Clostridium septicum. Definitive treatment was discussed including debridement and graft insertion; however, patient decided on conservative management and was discharged on intravenous antibiotics. Unfortunately, as in most cases of emphysematous aortitis that do not undergo surgical management, the patient succumbed to his illness. The lesson provided will be the epidemiology of emphysematous aortitis, presentation, diagnosis, management, and prognosis through a case report.

A considerable percentage of the genome is dedicated to the ubiquitin-proteasome system, with the yeast genome predicted to encode approximately 100 ubiquitin ligases (or E3s), and the human genome predicted to encode more than 600 E3s. The most abundant class of E3s consists of RING finger-containing proteins. Although many insights have been obtained regarding the structure and catalytic mechanism of the E3s, much remains to be learned about the function of the individual E3s. Here we characterize IRC20, which encodes a dual RING- and Snf/Swi family ATPase domain-containing protein in yeast that has been implicated in DNA repair. We found that overexpression of IRC20 causes two transcription-associated phenotypes and demonstrate that the Irc20 RING domain possesses ubiquitin E3 activity in vitro. Two mass spectrometry approaches were undertaken to identify Irc20-associated proteins. Wild-type Irc20 associated with Cdc48, a AAA-ATPase that serves as an intermediary in the ubiquitin-proteasome system. A second approach using a RING mutant derivative of Irc20 detected increased association of the Irc20 mutant with SUMO. These findings provide a foundation for understanding the roles of Irc20 in transcription and DNA repair.

The availability of an annotated genome sequence for the yeast Saccharomyces cerevisiae has made possible the proteome-scale study of protein function and protein–protein interactions. These studies rely on availability of cloned open reading frame (ORF) collections that can be used for cell-free or cell-based protein expression. Several yeast ORF collections are available, but their use and data interpretation can be hindered by reliance on now out-of-date annotations, the inflexible presence of N- or C-terminal tags, and/or the unknown presence of mutations introduced during the cloning process. High-throughput biochemical and genetic analyses would benefit from a “gold standard” (fully sequence-verified, high-quality) ORF collection, which allows for high confidence in and reproducibility of experimental results. Here, we describe Yeast FLEXGene, a S. cerevisiae protein-coding clone collection that covers over 5000 predicted protein-coding sequences. The clone set covers 87% of the current S. cerevisiae genome annotation and includes full sequencing of each ORF insert. Availability of this collection makes possible a wide variety of studies from purified proteins to mutation suppression analysis, which should contribute to a global understanding of yeast protein function.