L. Weatherbee

Viable vein graft preservation

Homologous vein grafts are becoming increasingly useful in patients without suitable autologous saphenous veins for peripheral arterial bypass procedures [4, 81. However, fresh veins are the only tissue that has been used successfully in homograft vascular reconstruction in terms of long-term patency [4]. The advantages of a reliable method of long-term storage of viable vein segments and the ultimate creation of a vein “bank” are therefore apparent. Dimethylsulfoxide (DMSO) is a low molecular weight compound that diffuses readily across cell membranes [2] and has been shown to be an effective cryoprotectant avoiding cellular dehydration, a major cause of cell death during freezing [2]. The DMSO has been used for successful cryopreservation of other tissues [3, 61, but has not been utilized for vein graft preservation. This study assesses a method for the longterm preservation of viable vein segments by freezing in liquid nitrogen with DMSO cryopreservation.

Large unit red cell cryopreservation with hydroxyethyl starch

Abstract Full units of red blood cells frozen with 14% hydroxyethyl starch (HES) yield cell recoveries near 97% and saline stabilities greater than 80%. Potassium leaves the cells during the freeze-thaw cycle and increases the extracellular concentration of this ion to near 35 meq/l. Unwashed cells (those with plasma present) and saline washed cells yield similar results. Storage of the thawed red cells at 4 °C for up to 48 hr causes little change in the cells. Examination by electron microscopy of samples from thawed units reveals some red cells with portions of their membrane missing. We believe this represents damage from the freeze-thaw cycle and also that all free supernatant hemoglobin does not arise from completely lysed cells.

Intradural extramedullary ganglioneuroma: Case report and review of the literature

The authors present a unique case of an intradural extramedullary ganglioneuroma in the thoracic spine of an adult. Intraspinal ganglioneuromas are rare, benign tumors of sympathetic nervous tissue origin, but exclusively intradural ganglioneuromas have not been reported.

Post-thaw suspension of red cells cryopreserved with hydroxyethyl starch.

Abstract Post-thaw suspension of red cells cryopreserved with hydroxyethyl starch (HES) gives rise to an increase in the quantity of supernatant hemoglobin and a reduction in cell recovery. This occurs regardless of the suspension media used but may be delayed by some solutions. Extended suspension with most solutions results in loss of intracellular contents from a number of cells. The resulting ghosts account for 12–14% of the total cell population. In the presence of 14% HES, deposits on the surface of damaged cells indicate that cellular contents are adherent to the cell membrane and therefore do not contribute to the free hemoglobin in the external solution. The result is a misleading high cell recovery value and suggests that this test does not accurately describe true cell damage in the presence of HES. Since the saline stability of suspended cells changes very little from that prior to suspension (at thaw), its value is a more accurate assessment of cell damage.

The effect of plasma on hydroxyethyl starch-preserved red cells

Summary Red blood cells frozen with 14% HES in 30-ml aliquots yield saline stabilities near 75%. When the cells are washed with 0.9% NaCl before freezing the saline stabilities increase to 83% (82.9 ± 1.5). The cell recoveries (near 98%) and the levels of supernatant hemoglobin (300 ± 25 mg%) remain nearly unchanged. The reduced saline stabilities are believed caused by the plasma or a plasma component since resuspending saline-washed red cells in autologous plasma gives stabilities identical to the unwashed cells. The improvement in saline stabilities by washing the red blood cells to remove the plasma occurs throughout a hematocrit range of 20–50%. Prefreeze washing could provide a method of improving the quality of HES-preserved red blood cells.

Primary mucinous adenocarcinoma of renal pelvis in solitary pelvic kidney

Mucinous adenocarcinoma of the renal pelvis is a rare tumor. We report the case of a fifty-three-year-old man with this unusual cancer and review the literature. Usual features of this tumor include long duration of symptoms, an association with calculi and hydronephrosis, and a preoperative appearance of an inflammatory condition.

Periosteal bone apposition in chondroblastoma.

Periosteal bone apposition in chondroblastoma of long bones is more frequent than generally recognized. This should not cause confusion in differential diagnosis. The finding does not seem to have prognostic significance.

Red cells preserved with 10% hydroxyethyl starch: Effect of prefreeze washing

Abstract Prefreeze washing of red cells with saline and other wash solutions before freezing with 10% hydroxyethyl starch does not yield an improved product after thawing. The saline stabilities and cell recoveries are reduced and the level of supernatant hemoglobin increased. These data further support the use of 14% as the most acceptable concentration of hydroxyethyl starch for cryopreservation of red cells.

Ultrastructure of red cells frozen with hydroxyethyl starch

The freeze fracture appearance of red cells frozen in the presence of varying concentrations of hydroxyethyl starch (HES) is described. A technique is used which allows examination of a small portion of cells from a larger unit. The frozen cells appear distorted probably as a result of osmotic dehydration but indicate no evidence of intracellular ice. The frozen mixture with HES has three phases—a particulate phase consisting of the concentrated HES (and other salts), a sculptured ice phase and the red cells. When the concentration of HES is increased, the particulate phase becomes more prominent and at 14% HES appears to surround nearly all cells. In cells frozen in saline alone and 4% HES, the cytoplasm in a majority of cells has numerous cavities and depressions. Since such units haemolyse badly when thawed, it is possible that these regions indicate structural damage. In contrast, those units frozen with 14% HES (in which nearly 85% of the cells survive freeze‐thaw) possess cells which only infrequently have such regions in the cytoplasm.

Pseudolymphoma masquerading as colonic malignancy

The case of a patient with a constricting lesion of the hepatic flexure is presented. Radiographic and endoscopic findings in this patient could not conclusively distinguish a benign from a malignant process. The patient eventually underwent operation, at which time hemicolectomy and ileotransverse colostomy were performed. The final pathologic diagnosis of the resected lesion was pseudolymphoma. The definition and significance of this diagnosis are discussed.