Experience with the Amplatz retrievable vena caval filter. Work in progress

The Amplatz retrievable vena caval filter was designed in an attempt to decrease complications associated with the placement of Mobin-Uddin or Kimray-Greenfield filters. The design allows percutaneous retrieval, thus expanding application of the filter to situations requiring temporary prophylaxis against pulmonary embolism. Filters have been placed in 16 patients, nine (56%) for prophylactic purposes. All filters were easily inserted percutaneously. Complications occurred in three patients; these included complete thrombosis of the inferior vena cava below the filter, misplacement of one filter into the pericaval retroperitoneal tissue, and development of thrombus cranial to the filter. With the current introduction system, the possibility of filter misplacement has been essentially eliminated. No patient experienced symptoms suggestive of pulmonary embolism after filter insertion. One filter retrieval has been performed, with no complications.     

Isolated ventricular noncompaction in patients with chronic renal failure

Isolated ventricular noncompaction is a rare congenital disorder characterized by the presence of numerous prominent trabeculations and deep intratrabecular recesses which communicate with the ventricular cavity. This disease has a very bad prognosis. Two cases of isolated ventricular noncompaction in patients with chronic renal failure have been described. The first case is a 65-year-old male, on regular hemodialysis for 3.5 years due to mesangioproliferative glomerulonephritis. He was symptomless regarding signs of congestive heart failure, angina pectoris, systemic embolization or arrhythmia. The second case is a patient with chronic renal failure (due to renal calculosis) admitted because of non-ST elevation acute myocardial infarction. In both cases echocardiography revealed an enlarged left ventricle, with extremely thickened walls with two layers: a thin, compacted myocardium on the epicardial side, and a thicker noncompaction endocardial layer. Ratio between noncompaction part of the wall and compaction part was 2.56 in the first and 4.94 in the second case. Blood flow from the left ventricular cavity into recesses was recorded with Color Doppler. Oral anticoagulation therapy was introduced in both of them. Holter ECG in the first patient revealed an intermittent right bandle branch block and in the second patient, premature ventricular contractions. Neurological examination findings were normal in both patients. Echocardiography of first-degree relatives was performed in the first case and it was normal in all 5 relatives. In the second case it was not performed due to technical reasons (relatives live abroad). Regular echocardiographic follow-up of all patients with chronic renal failure is necessary in order to diagnose cardiovascular comorbidities including this rare abnormality and its complications.     

Effect of medial arch-heel support in inserts on reducing ankle eversion: a biomechanics study

Background  

Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running.     

An unusual case of smoldering AML with prolonged indolent clinical course and spontaneous remission in the terminal phase

An unusual case of acute myeloblastic leukemia (AML) with indolent clinical course and spontaneous remission in the terminal phase is described. A 63-year-old male has been diagnosed to suffer from AML, subtype M2. Chromosomal analysis showed 46,XY,del(6)(q21). Clinical course was slowly progressive (“smoldering” AML). The patient did not require cytoreductive drugs, and occasional supportive therapy was his only treatment. Five years from diagnosis patient exhibited spontaneous remission of the disease, accompanied with disappearance of del(6q) clone. Six months after, relapse occured and patient died from CNS bleeding. Additional curiosity in this case is the fact that patient's older brother died of acute lymphoblastic leukemia at the age of 71 years. Possible mechanisms of spontaneous remission of AML and genetic predisposition for human leukemia are discussed with a review of the literature.     

An optimum anti-melanoma response in mice immunized with fibroblasts transfected with DNA from mouse melanoma cells requires the expression of both syngeneic and allogeneic MHC-determinants

Most neoplasms do not induce antitumor immune responses that can control tumor growth. Tumor associated antigens (TAAs) are insufficiently immunogenic. A vaccine that augments the immunogenic properties of TAAs could be of importance in the treatment of cancer patients. In an animal model, we prepared a vaccine by transfection of highly antigenic allogeneic mouse fibroblasts (LM; H-2(k)) with DNA from B16 mouse melanoma cells. We then tested the transfected cells' immunogenic properties in C57BL/6 mice, syngeneic with the melanoma (H-2(b)). We hypothesized that the immunogenic properties of 'weak' TAAs formed by the neoplasm would be enhanced if they were expressed by highly antigenic cells. The results indicated that mice with melanoma treated by immunization with the DNA-transfected fibroblasts survived significantly longer than mice in various control groups. To investigate the contribution of MHC determinants expressed by the transfected cells to their immunogenic properties, we compared the antimelanoma responses in mice immunized with transfected cells that expressed allogeneic or syngeneic class I determinants. The results indicated that the immunogenic properties of the DNA-transfected cells were enhanced if the cells expressed allogeneic MHC determinants. The antimelanoma responses of greatest magnitude, however, mediated predominantly by CD8(+) T cells, were in mice immunized with transfected fibroblasts that expressed both syngeneic and allogeneic class I determinants.     

Immune reconstitution after autologous hematopoietic stem cell transplantation

Autologous hematopoietic stem cell transplantation has proved to be an effective treatment for certain hematologic malignancies. However, relapse rates are high during the first year after transplantation. These relapses are attributed to the failure of high-dose chemotherapy to eradicate minimal residual malignant disease. In allogeneic hematopoietic stem cell transplantation, the higher antitumor effects observed compared with those in autologous hematopoietic stem cell transplantation are based on the immunologically mediated graft-vs-tumor effect. Therefore, a better understanding of the mechanisms involved in immune reconstitution after hematopoietic stem cell transplantation may clarify the importance of various components of the recovery of the immune system as they pertain to eradication of residual tumor, as well as uncover possible interventions directed at maximizing this effect. This review focuses on immune reconstitution after autologous hematopoietic stem cell transplantation. Autologous hematopoietic stem cell transplantation is not affected by graft-vs-host disease or immunosuppressive therapy after transplantation to control graft-vs-host disease, providing a direct insight into the mechanisms involved in immune reconstitution after engraftment.     

Therapeutic options in patients with lymphoma and severe liver dysfunction

OBJECTIVES: To determine the long-term outcome of patients presenting with synchronous lymphoma and severe liver dysfunction and to describe the outcome of patients treated with initial mechlorethamine-based therapy used as a bridge to more conventional chemotherapy. PATIENTS AND METHODS: We reviewed the clinical course of all patients diagnosed as having lymphoma who presented with severe liver dysfunction and received intravenous mechlorethamine between September 1988 and February 2003 at the Mayo Clinic in Rochester, Minn. RESULTS: Forty-one patients were identified, 33 (80%) of whom had newly diagnosed, previously untreated lymphoma. Thirty-seven (90%) had non-Hodgkin lymphoma, and 4 (10%) had Hodgkin disease. Thirty-four patients (83%) had stage IV disease, and 31 (84%) of 37 had an intermediate-high International Prognostic Index. The median total bilirubin level before therapy was 10.7 mg/dL (range, 2.5-30.2 mg/dL), and the median alkaline phosphatase level was 982 U/L (range, 233-3415 U/L). In addition to mechlorethamine, 34 patients (83%) received concomitant corticosteroids, and 12 (29%) received concomitant rituximab. Twenty-two patients (54%) had sufficient improvement in liver function to receive subsequent standard chemotherapy. Nine patients (22%) are alive and disease-free at a median of 31 months (range, 4 to > or = 87 months) after mechlorethamine treatment. Factors associated with improved overall survival included improvement in bilirubin levels (P < .001) and receiving subsequent standard chemotherapy (P = .001). CONCLUSION: Mechlorethamine, high-dose corticosteroids, and rituximab are useful therapeutic interventions for this unique group of patients with lymphoma and severe liver dysfunction. Substantial clinical improvement and long-term survival are possible.