D614G spike glycoprotein (sgp) mutation in rapidly spreading severe acute respiratory syndrome coronavirus‐2 (SARS‐COV‐2) is associated with enhanced fitness and higher transmissibility in new cases of COVID‐19 but the underlying mechanism is unknown. Here, using atomistic simulation, a plausible mechanism has been delineated. In G614 sgp but not wild type, increased D(G)614‐T859 Cα‐distance within 65 ns is interpreted as S1/S2 protomer dissociation. Overall, ACE2‐binding, post‐fusion core, open‐state and sub‐optimal antibody‐binding conformations were preferentially sampled by the G614 mutant, but not wild type. Furthermore, in the wild type, only one of the three sgp chains has optimal communication route between residue 614 and the receptor‐binding domain (RBD); whereas, two of the three chains communicated directly in G614 mutant. These data provide evidence that D614G sgp mutant is more available for receptor binding, cellular invasion and reduced antibody interaction; thus, providing framework for enhanced fitness and higher transmissibility in D614G SARS‐COV‐2 mutant.

Sickle cell disease is one of the most common inherited hemoglobinopathies diagnosed in the United States. Patients often present with severe anemia, pain crises, infections, and vaso-occlusive phenomena. Complications of these disorders can lead to significant debilitating morbidity and mortality. Fat embolism syndrome (FES) is a rare and devastating complication of sickle cell disease. It usually presents with a rapidly deteriorating clinical course, and the prognosis is dismal. We report a case of FES in a 19-year-old African American male with a history of sickle cell disease who presented with tonic-clonic seizures and was found to have multi-organ failure. FES was diagnosed 20 days from a presentation based on blood cytopenias and magnetic resonance imaging findings that were obscured at the initial presentation. We describe in this report, the patient's course from presentation until diagnosis and resolution. Our case is peculiar as the patient had a very good outcome without the need for red blood cell (RBC) exchange; instead, supportive treatment and simple RBC transfusions were enough to change the clinical course of this almost fatal syndrome.

Pancreatic lymphoepithelial cysts are rare, benign, non-neoplastic unilocular or multilocular cystic lesions. These circumscribed pancreatic lesions are filled with keratinous material grossly and exhibit distinct microscopic features. Pancreatic lymphoepithelial cysts are like the more common lymphoepithelial cysts of the parotid glands, which have been associated with the diffuse infiltrative lymphocytosis syndrome often seen in patients with HIV infection. However, pancreatic lymphoepithelial cysts are rare and their association with HIV infection has not been established. The presence of secondary changes in non-neoplastic cysts such as goblet cell metaplasia that was present in our case is an important feature to be included in the differential diagnosis and not to be interpreted as a mucinous neoplasm, particularly on fine-needle aspiration specimen microscopic evaluation that would impact further management. Here we describe the diagnosis and treatment of lymphoepithelial cysts in a patient who was on highly active antiretroviral therapy for HIV infection and we provide a brief literature review. Defining the clinical characteristics of lymphoepithelial cysts in patients with HIV and determining accurate preoperative diagnostic procedures will be critical for establishing effective surgical and medical approaches to treating these cysts, which differ substantially from other more serious pancreatic cystic lesions.

Breast cancer is a heterogeneous disease that represents a major public health problem, it is the most common cancer and leading cause of cancer deaths among Nigerian women, a condition that may be predicated upon by inadequate knowledge about fundamental regimen necessary for cancer prevention, early detection and unavailability of necessary health requirement. Immunohistochemistry is now a standard methodology in pathology laboratories used in providing substantial information with regard to diagnosis, therapeutic prediction and prognosis of breast cancer. Little is known about the biology, molecular profile and optimal treatment of African Nigerian breast cancer. This article discusses the immunohistochemical and prognostic markers of breast cancer in Nigeria. Literature was reviewed mainly through Public Medline search with the terms "immunohistochemical, prognosis markers of breast cancer in Nigeria", hard copies of journal pages and conference paper on prognostic markers of breast cancer in Nigeria. There are many markers that characterizes breast cancer and provide information about choice of therapy and prognosis, but as a developing country, the need for effective enlightenment and screening programs at an earlier age is required to boost the fight against the dreaded disease called breast cancer ravaging our women.

Background Essential thrombocythemia (ET) is associated with increased risk of bleeding secondary to acquired von Willebrand syndrome (AVWS). Bleeding in ET requires urgent platelet reduction by cytoreductive therapy such as hydroxyurea or thrombocytapheresis. We report on the efficacy and safety of thrombocytapheresis in managing AVWS in a patient with ET and multivisceral transplantation. Case report The patient was a 51‐year‐old female who underwent multivisceral transplantation. Her postoperative course was complicated by bleeding from oral cavity, IV lines, gastrointestinal and upper respiratory tracts as well as vaginal bleeding, which coincided with ET flare with a platelet count of 1512 × 109/L. Coagulation studies including von Willebrand factor (vWF) antigen and activity, vWF propeptide antigen, and vWF multimer analysis were consistent with AVWS. Hydroxyurea was initiated. However, due to major bleeding, rapidly increasing platelet count, and uncertainty of response to hydroxyurea being given through the enteral tube, thrombocytapheresis was initiated for rapid platelet reduction. The patient tolerated the procedure well. Platelet count was reduced from 1636 × 109/L to 275 × 109/L with rapid cessation of bleeding. The patient's condition stabilized over the next few days; however, bleeding recurred with increasing platelet count, which required a second thrombocytapheresis 8 days after the first one. The patient was maintained on hydroxyurea 500 mg twice/day. At 11‐month follow‐up, she had a normal platelet count and no recurrence of bleeding. Discussion Thrombocytapheresis is safe and efficient in managing postoperative bleeding due to ET/AVWS in solid organ transplant patients. The procedure can be an adjunct to bridging therapy before response to hydroxyurea is achieved.