Implementation and adaptation of the Re-Engineered Discharge (RED) in five California hospitals: a qualitative research study.

BACKGROUND: Project Re-Engineered Discharge (RED) is an evidence-based strategy to reduce readmissions disseminated and adapted by various health systems across the country. To date, little is known about how adapting Project RED from its original protocol impacts RED implementation and/or sustainability. The goal of this study was to identify and characterize contextual factors influencing how five California hospitals adapted and implemented RED and the subsequent impact on RED program sustainability. METHODS: Participant observation and key informant and focus group interviews with 64 individuals at five California hospitals implementing RED in 2012 and 2013 were conducted. These involved hospital leadership, personnel responsible for Project RED implementation, hospital staff, and clinicians. Interview transcripts were coded and analyzed using a modified grounded theory approach and constant comparative analysis. RESULTS: Both internal and external contextual factors were identified that influenced hospitals' decisions on RED adaptation and implementation. These also impacted RED sustainability. External factors included: impending federal penalties for hospitals with high readmission rates targeting specific diagnoses, and access to external funding and technical support to help hospitals implement RED. Internal or organizational level contextual factors included: committed leadership prioritizing Project RED; RED adaptations; depth, accountability and influence of the implementation team; sustainability planning; and hospital culture. Only three of the five hospitals continued Project RED beyond the implementation period. CONCLUSIONS: The sustainability of RED in participating hospitals was only possible when hospitals approached RED implementation as a transformational process rather than a patient safety project, maintained a high level of fidelity to the RED protocol, and had leadership and an implementation team who embraced change and failure in the pursuit of better patient care and outcomes. Hospitals who were unsuccessful in implementing a sustainable RED process lacked all or most of these components in their approach.

Can we use gonadotropin plasma concentration as surrogate marker for BMI-related incomplete estrogen suppression in breast cancer patients receiving anastrozole?

BACKGROUND: BMI has been suggested to impact on estrogenic activity in patients receiving anastrozole resulting in a reduced treatment efficacy in obese women. Current evidence in this regard is controversially discussed. Since estradiol is inversely correlated with gonadotropins it can be assumed that an impact of BMI is also reflected by gonadotropin plasma concentrations. We aim at investigating the impact of BMI on the hormonal state of breast cancer (BC) patients receiving anastrozole indicated by LH, FSH and SHBG as well as estradiol. METHODS: We determined gonadotropin-, estradiol- and anastrozole- serum concentrations from postmenopausal, early stage breast cancer patients receiving upfront anastrozole within routine after care. Gonadotropin plasma concentrations were derived from the routine laboratory examination report. A liquid chromatography tandem mass spectrometry method was used for the measurement of anastrozole serum concentrations. BMI was assessed within the routine after-care check-up. RESULTS: The overall sample comprised 135 BC patients with a mean age of 65.3 years. BMI was significantly correlated with LH, FSH and SHBG. This association was neither influenced by age nor by anastrozole serum concentrations according to the regression model. Despite aromatase inhibition 12% of patients had detectable estrogen levels in routine quantification. CONCLUSION: Obese women have an altered hormonal situation compared to normally weight women under the same dose of anastrozole. Our study findings are a further indicator for the relevance of BMI in regard of anastrozole metabolism and possible estrogenic activity indicated by gonadotropin plasma level.

Comparison between the impact of morning and evening doses of rivaroxaban on the circadian endogenous coagulation rhythm in healthy subjects.

UNLABELLED: ESSENTIALS: It is unknown whether single rivaroxaban doses should best be administered in the morning or evening. Circadian rhythm of coagulation/fibrinolysis was measured after morning or evening intake of rivaroxaban. Evening intake of rivaroxaban leads to prolonged exposure to rivaroxaban concentrations. Evening intake of rivaroxaban better matches the morning hypofibrinolysis. BACKGROUND: A circadian variation of the endogenous coagulation system exists with hypercoagulability and hypofibrinolysis and a corresponding peak of cardiovascular thromboembolic events in the morning. So far, no information is given as to whether single daily doses of the new oral anticoagulant drug rivaroxaban should best be administered in the morning or the evening. MATERIALS AND METHODS: Sixteen healthy male or female volunteers with a mean age of 26 ± 7 years were included in this randomized, controlled, analyst-blinded cross-over clinical trial. All subjects were given three morning and three evening single doses of 10 mg rivaroxaban. Circadian rhythms of prothrombin fragment 1 + 2, plasminogen activator inhibitor, and plasmin-antiplasmin complex were measured before any medication intake, as well as after morning or evening medication intake. Rivaroxaban concentrations were determined by an anti-activated factor X assay and liquid chromatography-mass spectrometry. MAIN RESULTS: Concentrations of rivaroxaban were higher 12 h after evening intake of rivaroxaban than 12 h after morning intake (53.3 ng mL(-1) [95% confidence interval 46.0-67.8] vs. 23.3 ng mL(-1) [19.4-29.1, respectively]). Rivaroxaban intake in the evening reduced morning F1+2 concentrations better at 8:00 AM than did administration on awakening (85 ± 25 nmol L(-1) vs. 106 ± 34 nmol L(-1) , CI: 9.4-32.1). In addition, this suppression effect was longer lasting after evening intake. CONCLUSIONS: Evening intake of rivaroxaban leads to prolonged exposure to rivaroxaban concentrations and better matches the morning hypofibrinolysis. These results might help to further improve the efficacy and safety of rivaroxaban treatment.

Women in Control: Pioneering Diabetes Self-Management Medical Group Visits in the Virtual World.

Background: The current state of diabetes self-management (DSM) education and support for diabetic patients is inadequate, especially for minority women who experience disproportionately high rates of diabetes mellitus (DM) in the US. While DSM education and support enables individuals with diabetes to make positive lifestyle choices and achieve clinical goals, this type of support is difficult to deliver in medical practice settings. Virtual reality can assist DM patients and their clinical teams by providing effective educational tools in an engaging, learner-centered environment that fosters self-efficacy and skill proficiency. Methods: Our prior research demonstrated that virtual worlds are suitable for supporting DSM education. Building upon this success, we are now investigating whether DSM virtual world medical group visits lead to similarly effective health and educational outcomes compared to face-to-face medical group visits. Currently in year one of a five year randomized controlled trial, we aim to compare the effectiveness of a virtual world DSM medical group visit format versus a face-to-face DSM medical group visit format to increase physical activity and improve glucose control (HbA1c) among Black/African American and Hispanic women with uncontrolled DM. We will also conduct a qualitative study of participant engagement with the virtual world platform to characterize learners' interactions with the technology and assess its correlation with DSM behaviors and diabetes control. Discussion: Novel methods to promote diabetes self-management are critically needed, and the use of virtual world technology to conduct medical group visits offers a unique approach to such issue. If successful, our intervention will increase access to culturally-sensitive diabetes care and improve patient engagement in online DSM learning, leading to higher uptake of DSM behaviors and better diabetes control. Importantly, the program can be easily expanded to other chronic disease areas and scaled for widespread use.

Novel point mutation in fibrinogen (Innsbruck; BßArg44Gly). Phenotypic differences compared to another mutation (fibrinogen Nijmegen) at the same position.

This is a report of a novel fibrinogen point mutation (fibrinogen Innsbruck), a C/G point mutation at position 220 of exon two of the fibrinogen Bß-chain leading to BßArg44Gly. The heterozygous mutation was found in a 16-year-old adolescent, hospitalized for the management of juvenile depression, who suffered from multiple epistaxis episodes during his stay at the university hospital in Innsbruck, Austria. Fibrinogen (based on the Clauss method) and fibrinogen antigen levels were highly discrepant (86 vs. 223 mg/dl) with thrombin time and reptilase time being in the respective upper reference ranges. Densitometric analysis of electrophoretic band pattern showed a reduction of α-polymers, indicating an impaired fibrin polymerization. This is in agreement with structural analysis, which showed a disturbance of the flexibility and structure of the region surrounding the fibrinoeptide B cleavage site. Fibrinogen Nijmegen, a mutation at the same position, is causative for thrombosis, whereas fibrinogen Innsbruck appears to lead to a bleeding tendency, illustrating that even mutations at the same position can cause contrary symptoms.

Red blood units collected from bone marrow harvests after mononuclear cell selection qualify for autologous use.

BACKGROUND: After large volume bone marrow (BM) harvest, donors and patients can develop severe anaemia, because collected BM can contain up to 20% of their red cell mass. In a prospective analysis, we investigated the feasibility to recover red blood cells (RBCs) from the harvested BM and investigated whether these RBC units meet the quality requirements of the European Council. PATIENTS AND METHODS: From 19 patients (median age 51 yrs, range 31-77) with acute myocardial infarction, who participated in the MYSTAR study, a median volume of 1299 ml (range, 700-1870 ml) BM was collected. During BM processing, mononuclear cells (MNC) were separated using the Cobe Spectra apheresis system and the residual RBCs were collected in a separate bag. The quality of the collected RBCs was assessed by measuring LDH, free haemoglobin, potassium and lactate. Haemolysis was calculated and the intracellular concentration of ATP, ADP, AMP was determined by HPLC. RESULTS: RBC units recovered from BM after MNC separation had a mean volume of 312 +/- 95 ml with a haematocrit of 47 +/- 8.9%, a haemoglobin content of 51 +/- 15 g per unit, a haemolysis of 0.15 +/- 0.005%, a pH of 6.8 +/- 0.007 and an intracellular ATP concentration of 135 pmol/10(6) RBC +/- 41, which is comparable with freshly collected packed red blood cells (PRBCs). CONCLUSION: RBCs, collected from bone marrow harvests, can be used for autologous blood support to minimize allogeneic blood transfusions in donors and patients after large volume BM donation.

An inosine 5'-monophosphate dehydrogenase 2 single-nucleotide polymorphism impairs the effect of mycophenolic acid.

Mycophenolic acid (MPA) is a selective inhibitor of inosine 5'-monophosphate dehydrogenase (IMPDH), the rate-limiting enzyme of de novo synthesis of guanine nucleotides. The isoenzyme IMPDH2 predominates in activated lymphocytes, and its inhibition by MPA is part of standard immunosuppressive regimens. Yet, there are significant unexplained differences in efficacy and tolerability among patients. The objective of this study was to analyze whether frequent variants in the IMPDH2 gene lead to changes in IMPDH activity and to differences in responsiveness to MPA therapy. All 14 exons and intron-exon boundary regions of IMPDH2 were sequenced from genomic DNA probes from 100 healthy individuals. Two novel exonic single-nucleotide polymorphisms were identified in 1% and one intronic polymorphism (rs11706052) in 19% of the study population. Lymphocyte IMPDH activity and proliferation under three MPA concentrations (2.5, 10 and 25 micromol l(-1)) were compared in rs11706052 carriers and wild-type individuals. The presence of rs11706052 polymorphism reduced the antiproliferative effect of MPA on lymphocytes by approximately 50% compared with the IMPDH2 wild-type form at therapeutic relevant concentrations of 10 micromol l(-1) and 25 micromol l(-1). We conclude that a poorer response to MPA therapy can be explained in some individuals by the presence of the rs11706052 polymorphism.

Adherence to pressure garment therapy in adult burn patients.

Pressure garment therapy (PGT) is a generally accepted procedure to prevent hypertrophic scarring after severe burns. Wearing pressure garments is uncomfortable and challenging for the patient and, consequently adherence is low. In order to improve adherence, precise knowledge about the advantages and disadvantages of PGT is necessary. In this study we investigated specific aspects which inhibit or reinforce the application of PGT on the patients' part. Twenty-one patients participated in a semi-structured interview concerning their experiences with PGT. The complaints most frequently mentioned were 'physical and functional limitations' caused by the garments, 'additional effort' created by the need to care for garments and 'perceived deficiencies' of the treatment. At the same time, most of the patients reported coping strategies used to persevere with the therapy. Coping can be categorised into 'behavioural' and 'cognitive coping strategies'. Besides the 'expectation of success', 'emotional' as well as 'practical support' and experiencing 'good outcome' were motivating factors for the patients. Based on the analyses of limitations and resources, recommendations for future interventions enhancing adherence are outlined.

Systemic lupus erythematosus patients exhibit functional deficiencies of endothelial progenitor cells.

OBJECTIVE: SLE is characterized by an increased cardiovascular risk. Since endothelial progenitor cells (EPCs) have been described to serve as a biomarker for the CV risk and are known to be depleted in various diseases, we were interested if SLE would also be associated with altered peripheral EPC levels or functional abnormalities of these cells. METHODS: EPCs were quantified in 31 female SLE patients with different disease activity and in age-matched healthy controls (HCs) by FACS analysis and by colony forming unit (CFU) assay. Furthermore, EPC adhesion and migration capacity were tested. RESULTS: EPC levels were similar in HC and SLE when assessed by FACS (0.045 +/- 0.006% vs 0.036 +/- 0.007% within the lymphocyte gate) and by the CFU assay (18 +/- 3 vs 15 +/- 2 colonies/well). No correlation with disease activity could be observed, but SLE patients treated with chloroquine exhibited significantly decreased EPC levels (0.058 +/- 0.005% without vs 0.024 +/- 0.008% with chloroquine, P < 0.05). Addition of chloroquine to in vitro cultures also led to a decreased colony formation in SLE and in HC. When testing the adhesion and migration capacity of EPC on human umbilical vein endothelial cells (HUVEC), cells from SLE patients had reduced adhesion (19.2 +/- 3.5% vs 36.6 +/- 5.2% EPC/high power field, P < 0.02) and migratory activity (56 +/- 6 cells/random microscopic field in SLE vs 121 +/- 28 in controls, P < 0.02). CONCLUSION: The data reveal that EPCs are significantly affected in SLE. While circulating EPC levels are in the range of HC, they exhibit functional deficiencies that may lead to impaired tissue availability.

TOS-surgery via a single supraclavicular incision.

BACKGROUND: We report about our experiences using a single supraclavicular incision at the base of the neck for Thoracic Outlet Syndrome (TOS) surgery. METHODS: 10 patients aged between 12 and 59 years (mean 31 years) underwent 12 times a TOS procedure. Patients suffered from compression of their brachial plexus with main affection of the ulnar nerve (9 out of 12 cases). Electroneurography was positive for TOS 4 times in 3 patients, in other 3 patients additionally a distal nerve compression syndrome was evident. In 7 cases (5 patients) a cervical rib was present on X-ray. In 10 cases (8 patients) the subclavian artery showed a stenosis behind the clavicle on MRI-angiography. In all cases the brachial plexus was prepared and a complete scalenotomy was performed. Whenever present the cervical rib was resected and in 2 cases the first rib (1 with/1 without cervical rib) was taken out. RESULTS: The surgical procedures did not cause relevant complications. All patients were without discomfort within 6 months, including the nerve regeneration disturbances. One patient suffered from TOS recurrence 10 months after surgery (scalenotomy without resection of the 1st rib). CONCLUSION: The single supraclavicular incision provided sufficient access to the structures of the brachial plexus, the subclavian artery and the cervical and 1st rib in all cases. The procedure produced not only sufficient pain relief and normalized extremity function but also a cosmetically acceptable, nearly invisible scar.

Comparison of different decellularization procedures of porcine heart valves.

BACKGROUND: Tissue engineering of heart valves should avoid the disadvantages of conventional prostheses. In this study we tested different decellularization procedures for their potential of cell removal and their ability to preserve the matrix. METHODS: Specimens of porcine aortic and pulmonary roots were treated with either trypsin or sodium-dodecyl-sulfate (SDS) or Triton-X 100 and sodium-deoxycholate with a range of concentrations. Tissue samples were then processed for scanning electron microscopy and laser scanning microscopy. RESULTS: Trypsin achieved only incomplete decellularization and caused severe structural alterations of the matrix. In contrast SDS removed cells completely but caused strong structural alterations. Treatment with Triton-X100 and sodium-deoxycholate achieved both complete decellularization and preservation of the matrix structure. CONCLUSION: Techniques of decellularization are highly variable in efficiency and matrix preservation and was best achieved in our study with Triton-X100 and sodium deoxycholate.

Early failure of the tissue engineered porcine heart valve SYNERGRAFT in pediatric patients.

OBJECTIVES: The first tissue engineered decellularized porcine heart valve, Synergraft (Cryolife Inc., USA) was introduced in Europe as an alternative to conventional biological valves. This is the first report of the rapid failure of these new grafts in a small series. MATERIALS AND METHODS: In 2001, 2 model 500 and 2 model 700 Synergraft valves were implanted in four male children (age 2.5-11 years) in the right ventricular outflow tract as a root. Two patients had a Ross operation and two had a homograft replacement. RESULTS: The cryopreserved Synergraft valves appeared macroscopically unremarkable at implantation. Recovery from surgery was uneventful and good valve function was demonstrated postoperatively. Three children died, two suddenly with severely degenerated Synergraft valves 6 weeks and 1 year after implantation. The third child died on the 7th day due to Synergraft rupture. Subsequently the fourth graft was explanted prophylactically 2 days after implantation. Macroscopically all four grafts showed severe inflammation starting on the outside (day 2 explant) leading to structural failure (day 7 explant) and severe degeneration of the leaflets and wall (6 weeks and 1 year explant). Histology demonstrated severe foreign body type reaction dominated by neutrophil granulocytes and macrophages in the early explants and a lymphocytic reaction at 1 year. In addition significant calcific deposits were demonstrated at all stages. Surprisingly pre-implant samples of the Synergraft revealed incomplete decellularization and calcific deposits. No cell repopulation of the porcine matrix occurred. CONCLUSION: The xenogenic collagen matrix of the Synergraft valve elicits a strong inflammatory response in humans which is non-specific early on and is followed by a lymphocyte response. Structural failure or rapid degeneration of the graft occurred within 1 year. Calcific deposits before implantation and incomplete decellularization may indicate manufacturing problems. The porcine Synergraft treated heart valves should not be implanted at this stage and has been stopped.

Quality of packed red blood cells and platelet concentrates collected by multicomponent collection using the MCS plus device.

The demand for blood components is constantly increasing, while the exclusion criteria for donors are strengthened in order to reach maximal safety for donors and patients. To counterbalance reduced availability of volunteers, multicomponent collections (MCC) is an attractive approach to produce more than one component during a single apheresis procedure from one donor, such as packed red blood cells (PRBCs) and platelet concentrates (PCs). Further, the exposures of patients to a limited number of donors reduces the possibility of alloimmunization and transfusion-related diseases. We measured the quality of PRBCs and PCs obtained by MCC, using the MCS+ device with the LDPRBC program, Revision B, and compared them with the quality of manually collected PRBCs and PCs collected with the Revision C2 of the MCS+. We found higher pH levels and lower hemolysis assessed by means of fHb and K+ in the supernatant of PRBCs over the whole storage period of 42 days in MCC-derived PRBCs. The functional metabolism assessed by intracellular ATP was higher in PRBCs collected by MCC than in manually collected units. Furthermore, PCs obtained during MCC showed an increase in p-selectin expression on day 5 of storage compared to PCs collected with the Revision C2 of the MCS+. The p-selectin expression on MCC platelets was within the range of p-selectin expression found in PCs obtained by other apheresis devices. These results indicate less storage lesion in MCC-derived PRBCs compared to manually collected units and no compromise in the quality of MCC PCs obtained in the same apheresis procedure.

Depletion of intracellular GTP results in nuclear factor-kappaB activation and intercellular adhesion molecule-1 expression in human endothelial cells.

The expression of the intercellular adhesion molecule 1 (ICAM-1) on the surface of endothelial cells plays an important role in immune-mediated processes. The induction by the proinflammatory cytokine interleukin (IL)-1beta is regulated by nuclear transcription factor kappaB (NF-kappaB). We studied the effect of an inosine-5'-monophosphate dehydrogenase (IMPDH) inhibitor, mycophenolic acid (MPA), on constitutive and IL-1beta-induced expression of ICAM-1 in human umbilical vein endothelial cells (HUVECs). Unexpectedly, pretreatment with MPA enhanced the constitutive expression and potentiated the induction of ICAM-1 by IL-1beta, as detected by flow cytometry. Northern blot analysis revealed an increase in ICAM-1 mRNA levels in cells treated with MPA. This was associated with an increase in phosphorylation of IkappaB-alpha (an inhibitor of NF-kappaB), nuclear translocation of the NF-kappaB subunits p50 and p65 and their binding to DNA as detected by Western blotting, confocal microscopy, and electrophoretic mobility shift assay. The up-regulation of ICAM-1 by MPA was prevented by high doses (100 microM) of guanine or guanosine but not by physiological doses (0.1 microM), indicating that guanylates are involved in endothelial responses to IL-1beta. Cultivation of HUVECs in the absence of guanine enhanced further ICAM-1 expression during IMPDH inhibition. These results demonstrate that cytokine-mediated endothelial ICAM-1 expression can be modulated by IMPDH inhibition. We believe this represents a novel interaction between endothelial guanylate metabolism, NF-kappaB activation, and adhesion molecule expression.

A clinical study of a fibrinogen-based collagen fleece for dural repair in neurosurgery.

BACKGROUND: There is frequently a need for dural grafts to cover defects resulting from retraction, shrinkage, or excision following neurosurgical procedures. Many substances have been tried as possible dural substitution, and different tissues and materials have been evaluated for use in dural repair. METHOD: The authors performed a retrospective review of 288 consecutive neurosurgical procedures using a fibrinogen based collagen fleece (TachoComb), a resorbable mesh of collagen from horse tendons, coated with human fibrinogen, bovine thrombin, bovine aprotinin and riboflavin (for marking the coated side), for dural substitution. The fibrinogen and thrombin imitate the last step of the coagulation cascade. On contact with bleeding wounds or other body fluids the coagulation factors dissolve and a link is formed between the collagen carrier and the wound surface. Thrombin converts fibrinogen into fibrin by splitting off peptides. Aprotinin prevents premature lysis of the fibrin clot by plasmin. FINDINGS: Neither superficial or deep wound infections nor aseptic meningitis were noted. We found good fibrous incorporation of TachoComb into the surrounding normal dura. Postoperative cerebrospinal-fluid (CSF) leaks developed in only five cases, who had to be re-operated, upon as well as one patient with a rebleeding. In another four cases, there was notable subcutaneous cerebrospinal-fluid accumulation without CSF-leak. They required a lumbar cerebrospinal-fluid drainage. INTERPRETATION: We conclude that TachoComb is a valuable alternative to the patients fibrous tissues for dural repair in cases in which autogenous tissues are either unavailable or insufficient for proper reconstruction.

Prostaglandin-J2 induces synthesis of interleukin-8 by endothelial cells in a PPAR-gamma-independent manner.

PPARgamma is a transcription factor of nuclear receptor superfamily, involved in the regulation of inflammation. We investigated the influence of PPARgamma-ligands, 15-deoxy-delta12,14 prostaglandin-J2 (15d-PGJ2), and ciglitazone, on the generation of interleukin-8 (IL-8) by the human microvascular endothelial cell line (HMEC- 1). Expression of PPARgamma in HMEC-1 was confirmed by RT-PCR. Both PPARgamma-ligands tested induced the activation of PPAR, but the potency of ciglitazone was higher, as evidenced by luciferase assay. Resting HMEC-1 released about 150 pg/ml of IL-8 protein. Treatment with LPS increased the IL-8 secretion up to 1 ng/ml. 15d-PGJ2 potently and dose-dependently increased both the steady-state and LPS-induced generation of IL-8 mRNA and IL-8 protein. In contrast, neither basal nor LPS-elicited expression of IL-8 was influenced by ciglitazone. We conclude, that 15d-PGJ2 is a potent inducer of IL-8 production and can be a mediator of inflammatory response, but this effect is independent of PPARgamma activation.

Altered intracellular purine nucleotides in gamma-irradiated red blood cell concentrates.

BACKGROUND AND OBJECTIVES: Gamma irradiation at a dose of 30 Gy induces deterioration of erythrocytes, resulting in storage lesions that significantly shorten the shelf-life of packed red cell concentrates (RCCs). The aim of the present study was to investigate the effect of gamma irradiation on intracellular purine nucleotides of red blood cells during storage. MATERIALS AND METHODS: Three-day-old leucocyte-depleted saline-adenine-glucose-mannitol (SAGM)-preserved RCCs, obtained from the Blood Service of the Austrian Red Cross, were gamma irradiated with 30 Gy. Samples were taken on days 1, 2, 3 and 7 after irradiation and subsequently at weekly intervals up to the end the of shelf-life (day 39 after irradiation) and were investigated for the K+ and Na+ content in the supernatant, for intracellular concentrations of ATP, ADP, ITP, IDP, GTP and GDP of erythrocytes, and for haemolysis. RESULTS: Within the first 24 h after gamma irradiation, no metabolic or biochemical changes were detectable in the RCCs. The K+ concentration in the supernatant increased after 24 h, while the Na+ concentration decreased in irradiated units and this ion disequilibrium persisted until the end of the shelf-life. After an initial increase of intracellular ATP, ADP and GTP during the first week of storage, the intracellular concentrations of ATP, ADP, GTP and ITP decreased, while IDP increased. The decrease of ATP and ADP was found to be more pronounced in irradiated units. At the end of the shelf-life, the ATP, GTP and ITP concentrations of irradiated RCCs had decreased to < 10% of the initial level and the critical threshold of 0.8% haemolysis was reached. CONCLUSION: Gamma irradiation of SAGM-preserved RCCs leads to serious deterioration of the purine nucleotide metabolism of erythrocytes during storage, which can reduce the in vivo recovery of the transfused red cells.

Effect of mycophenolate mofetil therapy on inosine monophosphate dehydrogenase induction in red blood cells of heart transplant recipients.

BACKGROUND: Mycophenolic acid is reported to provide effective immunosuppression by inhibiting inosine monophosphate dehydrogenase. In an attempt to monitor the biological effects of long-term therapy with mycophenolate mofetil, we measured levels of guanosine 5' triphosphate and adenosine 5' triphosphate in red blood cells (RBCs) of patients after heart transplantations. METHODS: Fifty-two patients enrolled in the study were randomly assigned to one of two groups. Patients in the control group (n = 27) received cyclosporine A (INN, ciclosporin), azathioprine, and prednisone. Patients in the study group (n = 25) were switched from azathioprine to mycophenolate mofetil 3 months after the heart transplantation. Adenosine 5' triphosphate and guanosine 5' triphosphate levels were determined by means of HPLC. The activities of inosine monophosphate dehydrogenase and hypoxanthine-guanine phosphoribosyltransferase, which are responsible for guanine nucleotide formation, were measured in RBCs by radiochemical methods. RESULTS: Adenosine 5' triphosphate levels were unchanged in patients treated with mycophenolate mofetil, whereas those of the control group who received azathioprine (from 142 +/- 26 pmol/10(6) RBCs to 165 +/- 25 pmol/10(6) RBCs; P <.001) increased. As the length of mycophenolate mofetil therapy increased, patients in the study group showed significantly elevated guanosine 5' triphosphate levels (15.6 +/- 6.1 pmol/10(6) RBCs versus 6.6 +/- 2.1 pmol/10(6) RBCs; P <.001) and a 5-fold increase in inosine monophosphate dehydrogenase activity (108.6 +/- 13.3 pmol/mg of protein per hour versus 22.5 +/- 1.7 pmol/mg of protein per hour; P <.001) compared with the control group. In addition, a slight but significant enhancement of hypoxanthine-guanine phosphoribosyltransferase activity was seen in the mycophenolate mofetil group. CONCLUSIONS: Our studies have shown that long-term administration of mycophenolate mofetil is associated with increasing guanosine 5' triphosphate levels in RBCs as the result of an induction of inosine monophosphate dehydrogenase and hypoxanthine-guanine phosphoribosyltransferase activities in erythrocytes.

Adhesion molecule behavior during rejection and infection episodes after heart transplantation.

In cardiac transplant recipients the release of soluble cellular adhesion molecules intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-Selectin into serum is pronounced during immune activation. It is uncertain whether there is a specific pattern of release during infection or cardiac allograft rejection. In a prospective study, 30 consecutive cardiac allograft recipients were followed for a median period of 11.4 months (range 1-34). Soluble ICAM-1 (sICAM-1), soluble VCAM-1 (sVCAM-1) and soluble E-Selectin (sE-Selectin) were measured in addition to acute phase proteins (C-reactive protein, alpha1-antitrypsin), complement factors (C3, C4) and beta2-microglobulin. The measured serum levels were correlated with the clinical status of the transplant recipient: 1) uneventful clinical status; 2) asymptomatic infection; 3) symptomatic infection and 4) rejection. Forty age-matched healthy subjects served as controls. Six days before biopsy-proven cardiac allograft rejection sICAM-1-release started to increase (p < 0.05) as compared to uneventful clinical status. The peak concentration of sICAM-1 was measured three days before rejection. On the day of rejection, serum concentrations of sICAM-1 (p < 0.001) and sVCAM-1 (p < 0.05) were increased, whereas sE-Selectin was not markedly elevated. In symptomatic infections, the serum concentrations of sICAM-1 (p < 0.001) and sVCAM-1 (p < 0.05) were elevated at the day of diagnosis and both parameters reached peak levels three days after onset of chemotherapy. In multivariate analysis soluble adhesion molecules only weakly discriminated between rejection and infection (sensitivity: 13%, specificity: 95%). Although, in combination with routine blood parameters the discriminatory power could be improved (sensitivity: 85%, specificity: 85%) the clinical utility of these markers in non-invasive monitoring is limited.