A Rare Case of Donor-Derived Renal Cell Carcinoma in a Kidney Transplant Recipient.

BACKGROUND The incidence of renal cell carcinoma (RCC) in transplanted kidneys is reported to be about 0.2%, which makes this case exceedingly rare. Risk factors include older age of the donors, smoking, obesity, and hypertension. Higher incidences of allograft RCC have been seen in patients who received a kidney from a deceased donor rather than from a living donor. CASE REPORT A 71-year-old woman with end-stage renal disease underwent deceased donor kidney transplantation (DDKT) 1 year before presentation. The immune-suppressive regimen was Envarsus, Myfortic, and prednisone. Allograft functioned with a baseline creatinine of 1.4-1.5 mg/dL. The patient presented due to recurring UTIs, which prompted the ultrasound that showed a mass on the allograft. Abdominal MRI demonstrated a 3.5-cm mass in the upper pole. Biopsy showed clear-cell RCC, Fuhrman nuclear grade 3. The patient underwent a partial nephrectomy. Following the nephrectomy, baseline serum creatinine was 1.7-2 mg/dL. The patient was discharged with immunosuppressive therapy consisting of Myfortic, prednisone, and Rapamune after diagnosis. CONCLUSIONS There are no standard treatment guidelines or optimal immune therapy for the management of allograft RCC in renal transplant recipients. Options include radical nephrectomy, nephron-sparing surgery (NSS), radiofrequency ablation (RFA), and active surveillance. According to a systematic review, the recurrence of cancer after partial nephrectomy was 3.6% after 3.1 years, which was similar to non-transplanted kidneys. There is not enough evidence to support screening for RCC in patients with transplanted kidneys, but constitutional symptoms like recurrent UTIs should prompt further investigation for potential malignancies in these patients.

Graves' Disease Exacerbation with Impending Thyroid Storm After SARS-CoV-2 Infection: A Case Report.

BACKGROUND Since the COVID-19 pandemic, several cases of COVID-19 have been linked to the development of autoimmune disorders, including of the thyroid. Graves' disease (GD) is a rare complication that can occur following SARS-CoV-2 infection. Reports have linked COVID-19 to new onset and exacerbation of GD. We present a case of a 42-year-old woman with a history of GD presenting with impending thyroid storm 3 weeks following a diagnosis of COVID-19. CASE REPORT A 42-year-old woman with a history of GD presented to the Emergency Department (ED) for an acute exacerbation of hyperthyroidism 3 weeks after SARS-CoV-2 infection was diagnosed on a home test. Symptoms included daily headaches, increased bilateral eye pressure, fatigue, muscle weakness, episodes of confusion and agitation, persistent heart palpitations, and goiter. Elevated free T4 of 5.57, free T3 of 15.68, total T3 of 4.43, and near-absent thyroid stimulating hormone were noted. The Burch-Wartofsky scale was 40, which was concerning for an impending thyroid storm; however, at the time of admission, she was not in a thyroid storm. Treatment included propylthiouracil, potassium iodide oral solution, and propranolol, with symptom improvement. Due to prior history of intolerance to antithyroid medications and recent exacerbation, a thyroidectomy was performed once she was in a euthyroid state. CONCLUSIONS Our case demonstrates the importance of recognizing COVID-19 as an etiology or a trigger for new onset or exacerbation of GD. Our case highlights that being vigilant to recognize the association between COVID-19 and thyroid abnormalities for early diagnosis and treatment is imperative.

Background-Free Detection of Spin-Exchange Dynamics at Ultra-Low Magnetic Field.

Ultra-low field nuclear magnetic resonance spectroscopy (NMR) and imaging (MRI) inherently suffer from a low signal-to-noise ratio due to the small thermal polarization of nuclear spins. Transfer of polarization from a pre-polarized spin system to a thermally polarized spin system via the Spin Polarization Induced Nuclear Overhauser Effect (SPINOE) could potentially be used to overcome this limitation. SPINOE is particularly advantageous at ultra-low magnetic field, where the transferred polarization can be several orders of magnitude higher than thermal polarization. Here we demonstrate direct detection of polarization transfer from highly polarized 129 Xe gas spins to 1 H spins in solution via SPINOE. At ultra-low field, where thermal nuclear spin polarization is close to background noise levels and where different nuclei can be simultaneously detected in a single spectrum, the dynamics of the polarization transfer can be observed in real time. We show that by simply bubbling hyperpolarized 129 Xe into solution, we can enhance 1 H polarization levels by a factor of up to 151-fold. While our protocol leads to lower enhancements than those previously reported under extreme Xe gas pressures, the methodology is easily repeatable and allows for on-demand enhanced spectroscopy. SPINOE at ultra-low magnetic field could also be employed to study 129 Xe interactions in solutions.

Genetics, Treatment, and New Technologies of Hormone Receptor-Positive Breast Cancer.

The current molecular classification divides breast cancer into four major subtypes, including luminal A, luminal B, HER2-positive, and basal-like, based on receptor gene expression profiling. Luminal A and luminal B are hormone receptor (HR, estrogen, and/or progesterone receptor)-positive and are the most common subtypes, accounting for around 50-60% and 15-20% of the total breast cancer cases, respectively. The drug treatment for HR-positive breast cancer includes endocrine therapy, HER2-targeted therapy (depending on the HER2 status), and chemotherapy (depending on the risk of recurrence). In this review, in addition to classification, we focused on discussing the important aspects of HR-positive breast cancer, including HR structure and signaling, genetics, including epigenetics and gene mutations, gene expression-based assays, the traditional and new drugs for treatment, and novel or new uses of technology in diagnosis and treatment. Particularly, we have summarized the commonly mutated genes and abnormally methylated genes in HR-positive breast cancer and compared four common gene expression-based assays that are used in breast cancer as prognostic and/or predictive tools in detail, including their clinical use, the factors being evaluated, patient demographics, and the scoring systems. All these topic discussions have not been fully described and summarized within other research or review articles.

A Comprehensive Review of COVID-19 Virology, Vaccines, Variants, and Therapeutics.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative pathogen of the coronavirus disease 2019 (COVID-19), has caused more than 179 million infections and 3.8 million deaths worldwide. Throughout the past year, multiple vaccines have already been developed and used, while some others are in the process of being developed. However, the emergence of new mutant strains of SARS-CoV-2 that have demonstrated immune-evading characteristics and an increase in infective capabilities leads to potential ineffectiveness of the vaccines against these variants. The purpose of this review article is to highlight the current understanding of the immunological mechanisms of the virus and vaccines, as well as to investigate some key variants and mutations of the virus driving the current pandemic and their impacts on current management guidelines. We also discussed new technologies being developed for the prevention, treatment, and detection of SARS-CoV-2. In this paper, we thoroughly reviewed and provided crucial information on SARS-CoV-2 virology, vaccines and drugs being used and developed for its prevention and treatment, as well as important variant strains. Our review paper will be beneficial to health care professionals and researchers so they can have a better understanding of the basic sciences, prevention, and clinical treatment of COVID-19 during the pandemic. This paper consists of the most updated information that has been available as of June 21, 2021.

The role of thoracic endovascular repair in elective, symptomatic and ruptured thoracic aortic diseases.

OBJECTIVES: Thoracic endovascular aortic repair (TEVAR) has emerged as a safe procedure in the treatment of a wide spectrum of descending thoracic aortic pathologies, with satisfactory results both in elective and urgent settings. We investigated the results of our elective, urgent and emergency TEVAR interventions. METHODS: A single-centre retrospective analysis of all consecutive patients undergoing TEVAR from 2010 to 2016 was performed. Primary end point of the study was early mortality, whereas the secondary end points included major complications according to the urgency of the procedure. The analysis was further conducted comparing symptomatic, asymptomatic and ruptured cases. RESULTS: Two hundred and eight patients were treated with TEVAR between January 2010 and April 2016 (mean age 67 ± 12 years, 142 men, 68.3%). Patients undergoing TEVAR as a first-stage procedure for complex thoraco-abdominal repair were excluded. The indication for treatment was a dissection in most cases (n = 92, 44.2%; acute dissection in 40 cases, 19.2%), followed by thoracic aneurysms (n = 64, 30.8%), penetrating aortic ulcers (n = 37, 17.8%), intramural haematomas (n = 8, 3.8%), traumatic ruptures (n = 3, 1.4%) and other indications (n = 4, 1.8%). One hundred and eight procedures were performed electively and 100 urgently. Forty-three patients were treated on an emergency bas for aortic rupture, 44 urgently for thoracic pain and 13 for acute ischaemic complications of aortic dissection or other indications. Ischaemic complications of dissection included 1 case of mesenteric ischaemia, 3 cases of acute renal failure, 4 cases of limb ischaemia and multiple ischaemic complications in 4 cases. Other causes of urgent TEVAR included 1 patient bleeding from a bronchial artery treated with TEVAR after several embolization attempts. In-hospital mortality was 7.7%, significantly higher in the urgent setting (14% vs 1.9%, P = 0.001). Urgent procedures were also more frequently associated with major adverse clinical events (7.4% vs 26%, P = 0.0003) and specifically with paraplegia (2.8% vs 10%, P = 0.043). Perioperative mortality was significantly higher in the ruptured group compared to the symptomatic group (25.6% vs 2.3%, P = 0.002). When the analysis was conducted to compare the symptomatic and the asymptomatic patients, no differences in terms of perioperative mortality were detected. CONCLUSIONS: TEVAR is an effective treatment strategy in thoracic aortic disease. Though emergency repair of the ruptured thoracic aorta still shows high rates of perioperative mortality and morbidity, symptomatic non-ruptured and asymptomatic patients have comparable early outcomes.

Reductive Elimination of Hydrogen from Bis(trimethylsilyl)methyltin Trihydride and Mesityltin Trihydride.

Alkyltin trihydride [(Me3 Si)2 CHSnH3 ] was synthesized and the reductive elimination of hydrogen from this species was investigated. A methyl-substituted N-heterocyclic carbene reacts with the organotrihydride in dependence on stoichiometry and solvent to give a series of products of the reductive elimination and dehydrogenative tin-tin bond formation. Besides characterization of the carbene adduct of the alkyltin(II) hydride, a Sn4 chain was also isolated, encompassing two stannyl-stannylene sites, which are stabilized each as NHC-adducts. Complete dehydrogenation resulted to give either a carbene-stabilized distannyne or a metalloid Sn9 -cluster salt. Reductive elimination of hydrogen was also achieved with an excess of diethylmethylamine to give the alkyltin(II) hydride as a Lewis base free tetramer [(RSnH)4 ]. The method of cluster formation at low temperatures by hydrogen elimination was also transferred to the mesityl-substituted tin trihydride MesSnH3 . In this case [(MesSn)10 ], showing a [5]prismane structure, was isolated in good yield and characterized. NMR spectroscopic features of the propellane-type cluster [Trip6 Sn6 ] are reported.

Antegrade in situ stent-graft fenestration for the renal artery following inadvertent coverage during EVAR.

PURPOSE: To report the use of antegrade in situ fenestration as a bailout technique to rescue a renal artery after inadvertent coverage during endovascular aneurysm repair (EVAR). TECHNIQUE: The technique is demonstrated in a patient with a 6-cm infrarenal abdominal aortic aneurysm (AAA) and a short, angulated proximal neck. A type I endoleak persisted on completion angiography after implantation of a bifurcated Zenith stent-graft despite dilation with a compliant balloon. A Giant Palmaz stent mounted on a large compliant balloon successfully resolved the endoleak. After placing the stent, the left renal artery was covered completely by the main aortic graft material, leading to only marginal opacification on angiography. To preserve flow to the renal artery, a transseptal sheath and transseptal needle were introduced from the right femoral artery and used to puncture the abdominal stent-graft antegrade at the site of the left renal artery. A 0.018-inch guidewire could then be introduced into the left renal artery; following a number of maneuvers, a balloon-expandable stent was placed through the fenestration into the target vessel. On computed tomographic angiography 4 days postoperatively, the AAA remained excluded and both renal arteries were patent, with all side branches fully preserved. Renal function was completely restored. CONCLUSION: Antegrade in situ fenestration can facilitate immediate revascularization of inadvertently covered side branches in EVAR using a transseptal sheath and needle. If the anatomical features are supportive, antegrade in situ fenestration can be a useful bailout technique.

Hemodynamic impact of transseptal access to the ascending aorta in a porcine model.

PURPOSE: To evaluate the hemodynamic impact of transseptal sheath access to the ascending aorta using increasing sheath diameters. METHODS: Transseptal puncture was performed in 6 pigs (62±9 kg) facilitating guidewire passage across the left heart to the descending aorta to establish transseptal through-and-through access into the ascending aorta. Hemodynamic parameters were evaluated during 6- to 16-F sheath deployments and after sheath retraction according to a standardized protocol. Fluorescent microspheres were injected for quantitative assessment of myocardial and cerebral perfusion and left-right shunting volume. RESULTS: Cardiac output, heart rate, and central venous pressure (CVP) were stable throughout the study in all animals. The ratio between pulmonary artery pressure and mean arterial pressure was significantly higher during sheath deployment compared to after retraction (p<0.01), indicating transient mitral valve insufficiency. The ratio between left atrial pressure and CVP was significantly higher with the sheath in place (p<0.01), signaling transient left-right shunting; the hemodynamic alteration disappeared after sheath retraction. Myocardial perfusion (p=0.224), cerebral perfusion (p=0.209), and left-right shunting volume (p=0.111) were not significantly affected by the transseptal access. CONCLUSION: Transseptal access to the ascending aorta in a porcine model is feasible without persisting hemodynamic impairment or severe influence on myocardial or cerebral perfusion even with up to 16-F sheaths. Potential adverse effects need to be addressed before clinical use of this alternative access to the ascending aorta, aortic arch, and its side branches.

Transapical access for thoracic endograft delivery.

The purpose of this paper is to describe the technique of transapical deployment of a thoracic endograft and to discuss the specifics of this access. The technique of endograft deployment through a transapical access is demonstrated in a patient with a symptomatic 14-cm aortic arch aneurysm. The 73-year-old patient, with concomitant chronic obstructive airway disease and cardiovascular disease, had been denied open surgery. Femoral artery access was deemed contraindicated because of a more distal concomitant type III thoracoabdominal aneurysm, borderline renal failure and heavily calcified iliac arteries. Bilateral iliac-subclavian debranching and thoracic endografting via a combined transapical and left subclavian access successfully excluded the thoracic aortic aneurysm. The patient died within 24 hours postoperatively due to a massive myocardial infarction. In conclusion, transapical access for thoracic endograft delivery is feasible. Combined with complex debranching procedures in a challenging aneurysmal anatomy, it carries a high risk for periprocedural complications.