Epstein-Barr virus (EBV), a member of the herpes virus family, is a causative agent for infectious mononucleosis in young adults. It has an asymptomatic and subclinical distribution in about 90% to 95% of the world population based on seropositivity. EBV is associated with various lymphomas, nasopharyngeal carcinoma, and in immunocompromised states can give rise to aggressive lymphoproliferative disorders. Symptomatic patients mostly present with mild hepatitis, rash, oral symptoms, lymphadenopathy, and generalized malaise. Recently with the COVID-19 (coronavirus disease-2019) pandemic, hepatitis has been found to be related to acute EBV and cytomegalovirus reactivation versus acute infection in the absence of other major causes. We describe a case of EBV coinfection in a patient with resolving mild COVID-19 infection.

Slipping rib syndrome is a rare cause of abdominal or lower chest pain that can remain undiagnosed for many years. Awareness among health care personnel of this rare but significant disorder is necessary for early recognition. Prompt treatment can avoid unnecessary testing, radiographic exposure, and years of debilitating pain. A 52-year-old female was evaluated for a 3-year history of recurrent abdominal and lower chest pain. Pain was sharp, primarily located in the lower chest and subcostal region left more than right, waxing and waning, nonradiating, and aggravates with specific movements. She underwent frequent physical therapies, treated with multiple muscle relaxants and analgesics with minimal improvement. Imaging modalities including CT scan, MRI, and X-rays performed on multiple occasions failed to signify any underlying abnormality. Complete physical examination was unremarkable except for positive hooking maneuver. Dynamic flow ultrasound of lower chest was performed which showed slipping of the lowest rib over the next lowest rib bilaterally left worse than right, findings consistent with slipping rib syndrome. Slipping rib syndrome is caused by hypermobility of the floating ribs (8 to 12) which are not connected to the sternum but attached to each other with ligaments. Diagnosis is mostly clinical, and radiographic tests are rarely necessary. Hooking maneuver is a simple clinical test to reproduce pain and can aid in the diagnosis. Reassurance and avoiding postures that worsen pain are usually helpful. In refractory cases, nerve block and surgical intervention may be required.

No abstract

Spontaneous retroperitoneal hematoma is a rare clinical entity that is most commonly caused by renal tumors and vascular disease. In this article, we present a case of spontaneous retroperitoneal hemorrhage caused by polyarteritis nodosa in a patient who presented with severe left flank pain. He underwent computed tomography angiography of his abdomen that showed left retroperitoneal hematoma, which was followed by arteriogram that showed multiple bilateral renal artery aneurysms with active extravasation, findings consistent with polyarteritis nodosa. The patient underwent successful coiling of the bleeding vessel that secured the bleeding and was started on high-dose prednisone, which resulted in resolution of his symptoms.

No abstract

The power balancing is the issue that creates when voltage fluctuations occur in the DC microgrid. In order to compensate for the DC bus voltages in the DC microgrid, the energy storage system is used. This system absorbs or releases the power to make the DC bus voltages is stable. In this research, a bidirectional series resonant (BSR) converter is proposed which operates at the fixed frequency for the energy storage system. A simple PWM control technique is used for the power flow regulation in the system. The gain voltage of the BSR converter depends only on the duty cycle of the applied voltage and does not change the direction and amplitude of the power flow. Theoretically, after the calculations, the gain voltage of the BSR converter changed from minimum (zero) to maximum (unlimited) which means the designed converter is a buck-boost converter as well. This property of the BSR converter will help the researcher to use a wide range of voltage applications. The operations mode i.e. forward and backward modes, and the direction of the power flow can be changed smoothly by Pulse Width Modulation control. Zero voltage switching for all the voltage ranges of the active switches is also achieved in this research.

No abstract

Weissella confusa is a rare gram-positive, non-spore-forming, catalase-negative, gram-positive coccobacillus, and a pleomorphic gram-positive rod (GPR) often misidentified as Lactobacillus genus. It was first discovered in 1993 and is becoming identified due to the increasing use of DNA sequencing. The true incidence of this species has likely been underestimated and it has been implicated in poly-microbial bacteremia. We present an exceedingly rare case of its presentation found incidentally in a patient with a bio-prosthetic aortic and mitral valve that was successfully managed and treated.