An Epstein-Barr virus-positive diffuse large B-cell lymphoma presenting as multi-organ failure: a catastrophic lymphomatosis with fulminant visceral organ dissemination resulting in a precipitous death in a 59-year-old female with no identifiable etiology for immunodeficiency.

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (EBV+ DLBCL) of the elderly is an aggressive B-cell neoplasm related to age-associated impaired immunity. We report such a case in a 59-year-old woman with a catastrophic disease course. The patient initially presented with fever, fatigue, malaise and weakness over one-week period. Despite empirical treatment with antibiotics and antiviral agents, she subsequently developed multi-organ failure and coagulopathy. Radiographic imaging revealed hepatomegaly, splenomegaly, pleural effusion, and ascites. Her complete blood cell count showed marked leukocytosis, anemia and thrombocytopenia. Morphologic examination of blood smear demonstrated many abnormal plasmacytoid lymphocytes, and flow cytometric analysis detected an intermediate-large mature B-cell population (69%) without detectable surface immunoglobulin. High copy numbers of EBV genome were detected in the blood by PCR. A diagnosis of EBV+ DLBCL, leukemic phase, was made. Despite aggressive treatment and supportive care, the patient succumbed to multi-organ failure one week after initial presentation. Autopsy demonstrated EBV+ DLBCL infiltration in all the organs examined. This case describes an unusual presentation of EBV+ DLBCL and highlights the necessity of pertinent ancillary tests to avoid delay in the diagnosis and treatment.

Acral myxoinflammatory fibroblastic sarcoma fine needle aspiration: a case report.

Cytological diagnosis of low grade sarcomas can be a daunting task, owing to the varied cytomorphological appearances possible. We report a case of acral myxoinflammatory fibroblastic sarcoma (AMIFS) in a woman who presented with a longstanding mass on the dorsum of her left foot. The diagnosis was suggested by fine needle aspiration cytology and established by wide excision. Microscopic examination showed that fine needle aspirate smears of this lesion contained the characteristic features seen in the surgical excision of this AMIFS: myxoid material, spindled to epithelioid cells with variably prominent nucleoli, nuclear pseudoinclusions, bipolar cytoplasmic extensions, globules of extracellular material, and bizarre virocyte or ganglion-like giant cells.

Chondrogenic differentiation of adipose-derived adult stem cells in agarose, alginate, and gelatin scaffolds.

The differentiation and growth of adult stem cells within engineered tissue constructs are hypothesized to be influenced by cell-biomaterial interactions. In this study, we compared the chondrogenic differentiation of human adipose-derived adult stem (hADAS) cells seeded in alginate and agarose hydrogels, and porous gelatin scaffolds (Surgifoam), as well as the functional properties of tissue engineered cartilage constructs. Chondrogenic media containing transforming growth factor beta 1 significantly increased the rates of protein and proteoglycan synthesis as well as the content of DNA, sulfated glycosaminoglycans, and hydroxyproline of engineered constructs as compared to control conditions. Furthermore, chondrogenic culture conditions resulted in 86%, and 160% increases ( p < 0.05 ) in the equilibrium compressive and shear moduli of the gelatin scaffolds, although they did not affect the mechanical properties of the hydrogels over 28 days in culture. Cells encapsulated in the hydrogels exhibited a spherical cellular morphology, while cells in the gelatin scaffolds showed a more polygonal shape; however, this difference did not appear to hinder the chondrogenic differentiation of the cells. Furthermore, the equilibrium compressive and shear moduli of the gelatin scaffolds were comparable to agarose by day 28. Our results also indicated that increases in the shear moduli were significantly associated with increases in S-GAG content ( R2 = 0.36, p < 0.05 ) and with the interaction between S-GAG and hydroxyproline ( R2 = 0.34, p < 0.05 ). The findings of this study suggest that various biomaterials support the chondrogenic differentiation of hADAS cells, and that manipulating the composition of these tissue engineered constructs may have significant effects on their mechanical properties.

A biomechanical comparison of suture constructs used for coracoclavicular fixation.

There is no consensus regarding surgical treatment for severely dislocated acromioclavicular joints. Although many treatments are suture-based, the suture materials and resulting suture-bone constructs have been subjected to limited systematic evaluation. This study identifies the strongest and least deforming suture construct among those commonly used for such repairs. Each suture-based repair was tested on a simulated clavicle and coracoid process with the skeletal components distracted until the suture failed to obtain tensile strength. Additional groups of sutures were subjected to cyclic loading to determine resistance to deformation. Panacryl braid had significantly greater tensile strength than all other constructs: Polydioxanone (PDS) braid, Mersilene tape, and Ethibond #5. Deformation after cyclic loading of Panacryl braid, PDS braid, and two strands of Mersilene tape was significantly less than that of the other constructs. A bioabsorbable suture loop, such as Panacryl, can act as a temporary internal splint, maintaining acromioclavicular joint reduction long enough for ligamentous healing during rehabilitation, and can avoid complications associated with permanent fixation materials. Panacryl braid deserves serious consideration for coracoclavicular fixation because of its strength, resistance to deformation, and bioabsorbable properties.

Multipotent stromal cells derived from the infrapatellar fat pad of the knee.

Tissue engineering approaches for promoting the repair of skeletal tissues have focused on cell-based therapies involving multipotent stromal cells. Recent studies have identified such cells in several tissues in the adult human, including skin, muscle, bone marrow, and subcutaneous fat. This study examined the hypothesis that the infrapatellar fat pad of the adult knee contains progenitor cells that have the ability to differentiate into chondrocytes, osteoblasts, or adipocytes under appropriate culture conditions. Cells isolated from the fat pad stroma had a profile of cell-surface molecules similar but not identical to that of bone marrow-derived mesenchymal stem cells. Using defined culture conditions, fat pad-derived stromal cells were induced to differentiate cells with phenotypic characteristics of: (1) chondrocytes, synthesizing cartilage matrix molecules; (2) adipocytes, producing lipid vacuoles and leptin; or (3) osteoblasts, forming mineralized tissue. The culture conditions also modulated the expression of characteristic gene markers for each lineage. This study supports the hypothesis that multipotent stromal cells are present in many connective tissues in the adult human. Given its location and accessibility, the fat pad may prove to be a potential source of progenitor cells for musculoskeletal tissue engineering.