Tropheryma whipplei infection (Whipple's disease) in a patient after liver transplantation.

Whipple's disease (WD) is a rare infection caused by the bacterium Tropheryma whipplei that can affect multiple organs and most commonly occurs in the immunocompetent host. Only 3 cases of WD have been reported in the setting of immunosuppression for organ transplantation. Here, we report the first case of WD, to our knowledge, in a patient after liver transplantation with comorbid graft-versus-host-disease. We discuss the diagnostic challenges in this setting and the value of electron microscopy and in situ hybridization methods for confirming the infection. WD may be under-diagnosed in immunosuppressed transplant patients because the disease can present with atypical clinical and histological features that suggest other conditions.

Prognostic analysis of pre-transplant peripheral T-cell levels in patients receiving an autologous hematopoietic progenitor-cell transplant.

The purpose of this study was to evaluate pre-transplant T-cell status in autologous hematopoietic progenitor-cell transplantation (HPCT) recipients. Between 1999 and 2002 we prospectively enrolled 85 autologous HPCT recipients with solid tumors (N = 50) or hematological malignancies (n = 35). Patient diagnoses included breast cancer (N = 49), non-Hodgkin's lymphoma (N = 20), myeloma (N = 11), Hodgkin's disease (N = 3), germ-cell tumor (N = 1) and amyloidosis (N = 1). Levels of CD3, CD4, CD8, memory and naïve CD4, and CD8 T-cell subsets were analyzed before autologous HPCT. Autologous HPCT recipients presented with lower pre-transplant counts of CD3, CD4, but not CD8 T cells, as compared to healthy controls. Pre-transplant CD4 T-cell levels correlated with progression-free survival (PFS) (P = 0.002) and overall survival (OS) (P = 0.05), in patients with hematologic malignancies (P = 0.02) and breast cancer (P = 0.04). Specifically, pre-transplant memory CD4 + CD45RA - CD62L - T-cell levels correlated with PFS (P = 0.01). The prognostic effects of pre-transplant CD4 and CD4 + CD45RA - CD62L - T cells were independent of tumor diagnosis, tumor stage, tumor sensitivity, and, for breast cancer patients, Her2 / neu status. Our results suggest that pre-transplant CD4 T-cell status, specifically CD4 + CD45RA - CD62L - memory T cells, correlates with the outcome of autologous HPCT recipients. These observations suggest the feasibility of prospective identification of those patients at higher risk of relapse, based on their immune status.

Characterization of microcapsules: recommended methods based on round-robin testing.

Alginate beads, as well as microcapsules based on alginate, cellulose sulphate and polymethylene-co-guanidine, were produced at diameters of 0.4, 1.0 and 1.5 mm. These standard materials were tested, by independent laboratories, in regards to water activity, bead or capsule size, mechanical resistance and transport behaviour. The water activity and mechanical resistance were observed to increase with bead and capsule size. Transport properties (ingress) were assessed using a variety of low molar mass and macromolecular probes. It was observed that the penetration of Vitamin B12 increased with bead diameter, as did dextran penetration. However, for the membrane-containing microcapsules, larger membrane thickness, observed for the larger capsules, retarded ingress. The authors, who are part of a European working group, recommend that permeability be assessed either using a large range of probes or a broad molar mass standard, with measurements at one or two molar masses insufficient to simulate the behaviour in application. Mechanical compression is seen as a good means to estimate elasticity and rupture of beads and capsules, with the sensitivity of the force transducer, which can vary from microN to tens of N, required to be tuned to the anticipated bead or capsule strength. Overall, with the exception of the mechanical properties, the precision in the inter-laboratory testing was good. Furthermore, the various methods of assessing transport properties agreed, in ranking, for the beads and capsules characterized, with gels having smaller radii being less permeable. For microcapsules, the permeation across the membrane dominates the ingress, and thicker membranes have lower permeability.

Pectin coated hollow fiber polypropylene membranes.

The aim of this study was to prepare a composite membrane for the selective, extracorporeal removal of human LDL-cholesterol. Pectin coated on a porous polypropylene membrane (PP) was used as an active LDL adsorber. Three types of membrane preparations were performed: coating of native PP, coating after chemical etching and gamma-irradiated coated PP. Pectin coated fibers (PCF) were examined under scanning electron microscope (SEM) and tested for hydraulic permeability. As a result of the coating of native and etched PP membrane, pectin layers of various thicknesses (2-16 microm) and porosity were obtained. Irradiation by gamma rays gave no insoluble pectin layers.

A new pectin-based material for selective LDL-cholesterol removal.

A new material, natural polysaccharide-pectin, was tested for removal of human blood lipoproteins. Pectin was prepared in a granular form with the help of the specifically designed gelification device and tested in batch sorption experiments in vitro for removal of total cholesterol (TC), LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C) from human plasma. Pectin granules removed 40% of TC, 45% of LDL-C, and 36% of HDL-C on average with respect to the initial amounts whereas corresponding values for LA-40 Kanegafuchi adsorbent were 69%, 81%, and 33% in the same experimental conditions (shaking 1 g of sorbent sample with 2 ml of plasma).

Design of spherical carbon adsorbent for extracorporeal detoxification.

A special carbon adsorbent (CA), designed for use in extracorporeal detoxification by hemoperfusion, was produced from a spherical synthetic polymer by our own technolique and tested at a preclinical level. Comparison of mechanical properties, sorption and biocompatibility between CA and medical hemosorbents was made. The carbon adsorbent is hard, has a smooth surface, shows good sorption properties and has acceptable biocompatibility. These features qualify the carbon adsorbent for use in clinical hemoperfusion without any additional membrane coating.