Activated leukocytes and endothelial cells enhance retention of ultrasound contrast microspheres containing perfluoropropane in inflamed venules

PURPOSE: To characterize the flow dynamics of albumin ultrasound contrast microspheres containing perfluoropropane (PFP) in normal and inflamed microvasculature. MATERIALS AND METHODS: Mesenteric microvessels of rats were examined after an intravenous injection of fluorocein-labeled erythrocytes or PFP microspheres by fluorescence intravital microscopy with and without local application of 10(-8) M platelet activating factor (PAF) as an experimental form of inflammation. RESULTS: All the microspheres passed freely through arterioles and capillaries. Mean velocities of the microspheres in each vessel were closely correlated with those of erythrocytes. Only a minor fraction of the microspheres was retained in the venules (> or =0.1 s stoppage) by attachment to endothelial cells. The frequency of microsphere retention in venules was significantly enhanced by PAF (2.6+/-2.1%, P<0.01 vs. control), especially in regions with leukocyte adhesion. Treatment with a monoclonal antibody to intercellular adhesion molecule-1, P-selectin or the common leukocyte antigen inhibited PAF-induced microsphere retention in venules (P<0.05). In the inflamed microcirculation, a small subgroup of microspheres becomes attached to venular endothelial cells in regions with leukocyte adhesion via interaction among microspheres, activated leukocytes and endothelial cells via adhesion molecules. CONCLUSION: In inflamed microcirculation, a small subgroup of microspheres becomes attached to venular endothelial cells in regions with leukocyte adhesion via interaction among microspheres, activated leukocytes and endothelial cells via adhesion molecules. These results suggest that ultrasonography with microspheres has the potential to evaluate inflammatory site distribution as well as tissue perfusion.     

Quality of life improvements in dialysis patients receiving darbepoetin alfa

Short-acting hematopoietic agents can improve the quality of life (QOL) of hemodialysis patients, but questions remain regarding the domains of QOL affected, the relative importance of initial and final hemoglobin (Hb) concentrations, and the use of long-acting hematopoietic agents. We measured Hb concentrations and QOL in 487 hemodialysis patients who were switched from treatment with recombinant human erythropoietin to treatment with darbepoetin alfa. QOL was measured with the Japanese-language version of the SF-36, at the start of therapy with darbepoetin alfa and again 7-14 weeks later. We examined changes in QOL over time in the group as a whole, and in subgroups stratified by the change in Hb concentration. We also studied relationships between the final Hb concentration achieved and the magnitude of change in QOL. QOL scores increased significantly in all SF-36 domains except Social Functioning. The greatest increases were in vitality and in the two role-functioning domains. The magnitude of the increase in Hb concentration was related to the magnitude of the increase in QOL for only one subscale: Vitality. Patients with higher final Hb concentrations also had greater increases in Vitality scores. Hematopoiesis induced by darbepoetin alfa is associated with increased vitality and may also be associated with improved role functioning. Vitality increased significantly only in those patients with the greatest increases in Hb concentration and in those with higher final Hb concentrations.     

Hobson’s choice two-stage hepatectomy for multiple and bilobar colorectal liver metastases with portal vein embolization: report of two cases

Liver resection is recognized as the preferred treatment for patients with colorectal liver metastases (CLM) because it offers long-term survival; it is the only hope for a cure. However, in the majority of cases, liver surgery is contraindicated due to the small volume of the future remnant liver. To extend the surgical indications for CLM, a planned two-stage hepatectomy procedure with portal vein embolization (PVE) was developed specifically for patients with multiple and bilobar CLM. The rationale for performing the procedure was a concern about the possible overgrowth of intrafuture remnant liver lesions following PVE, and it was therefore recommended for all multiple bilobar CLM cases, even when one-stage hepatectomy was technically feasible. We recently performed Hobson’s choice two-stage hepatectomy in two cases for reasons different from those of the original planned two-stage hepatectomy. In the present report, we describe our Hobson’s choice two-stage hepatectomy strategy, which provided favorable short-term outcomes.     

A case of tooth autotransplantation after long-term cryopreservation using a programmed freezer with a magnetic field

This case report describes the treatment of a skeletal Class III malocclusion with autotransplantation of a cryopreserved tooth. To gain an esthetic facial profile and good occlusion, extraction of bimaxillary premolars and surgical therapy were chosen. The patient had chronic apical periodontitis on the lower left first molar. Although she did not feel any pain in that region, the tooth was considered to have a poor prognosis. Therefore, we cryopreserved the extracted premolars to prepare for autotransplantation in the lower first molar area because the tooth would probably need to be removed in the future. The teeth were frozen by a programmed freezer with a magnetic field (CAS freezer) that was developed for tissue cryopreservation and were cryopreserved in −150°C deep freezer. After 1.5 years of presurgical orthodontic treatment, bilateral sagittal split ramus osteotomy was performed for mandible setback. Improvement of the facial profile and the occlusion were achieved in the retention phase. Six years after the initial visit, the patient had pain on the lower left first molar, and discharge of pus was observed, so we extracted the lower left first molar and autotransplanted the cryopreserved premolar. Three years later, healthy periodontium was observed at the autotransplanted tooth. This case report suggests that long-term cryopreservation of teeth by a CAS freezer is useful for later autotransplantation, and this can be a viable technique to replace missing teeth.