A novel MHC-associated Proteinase 3 peptide isolated from primary chronic myeloid leukaemia cells further supports the significance of this antigen for the immunotherapy of myeloid leukaemias

Three of the most promising antigens for immunotherapy of chronic myelogenous leukaemia (CML) include the specific fusion-protein, Bcr/Abl, and the overexpressed proteins WT1 and Proteinase 3. The clinical significance of Proteinase 3 as a target in myelogenous leukaemias has been bolstered by detection of high frequencies of cytotoxic CD8+ lymphocytes specific for this antigen in patients undergoing immune therapies. Our investigation aimed to directly identify MHC-ligands derived from these antigens and presented on CML blasts by means of affinity-purification and mass spectrometric peptide-sequencing. Although no known or potential new epitopes were discovered for Bcr/Abl or WT1, a novel peptide from Proteinase 3 was detected among the more abundant MHC-ligands. Additionally, MHC-ligands derived from known immunogenic proteins overexpressed as a result of Bcr/Abl transformation were also identified. Our investigation is the second of only a small number of studies to identify a peptide from Proteinase 3 among the more abundant MHC-associated peptides and thus implies that peptides from this antigen are among the more abundantly presented of the known leukaemic antigens. Taken in conjunction with clinical observations of functional Proteinase 3 specific CTL in patients', these data further support the application of this antigen as an immunotherapeutical target for myelogenous leukaemias.

Extraanatomical coronary artery bypass grafts on the beating heart for management of the severely atherosclerotic ascending aorta

BACKGROUND

Crossclamping a severely atherosclerotic ascending aorta carries a significant risk of stroke in coronary artery bypass grafting. Besides other techniques aortic no touch concepts are increasingly applied for management of this problem.

METHODS

Out of 407 patients undergoing epiaortic scanning during coronary artery bypass grafting 38 (9.3%) exhibited severe ascending aortic atherosclerosis. 22 of these patients (18 male, 4 female, age 72 (57-79) years, Parsonnet Score 11 (0-18), Euro Score 8 (2-13), McSPI Stroke Risk Index 6 (1-30) %) were operated on using a beating heart and aortic no touch technique. All patients received at least one internal mammary artery (IMA) in situ graft and additional extraanatomical bypass conduits: venous Y-graft from the IMA (n=14), arterial Y-graft from the IMA (n=3), vein graft from the axillary artery (n=3), vein graft from the IMA stump (n=2), vein graft from the innominate artery (n=2).

RESULTS

No stroke occurred. The rate of perioperative myocardial infarction (CKMB rt; 50 U/l) was 5/22. Median ICU length of stay was 54 (15-1245) h. Hospital mortality was 2/22. Pre- and postoperative angina class (CCSC) were 3.3 +/- 0.9 and 1.4 +/- 0.9 respectively (p<0.001). After a median follow up period of 8 months 3 deaths, one stroke, and one myocardial infarction occurred. On 3D multislice CT scan reconstructions which were performed in 13 patients during the first postoperative year all IMA grafts to the LAD and 11 out of 13 extraanatomical vein grafts were shown to be patent.

CONCLUSION

Performance of beating heart extraanatomical coronary artery bypass grafts for management of a heavily diseased ascending aorta can result in a very low stroke rate despite a considerable stroke risk. The complexity of the procedures may be reflected by a relatively high rate of perioperative myocardial infarctions. Perioperative mortality as well as short term patency of extraanatomical bypass grafts seem to be acceptable.

Off pump coronary artery bypass grafting in EuroSCORE high and low risk patients

OBJECTIVE

Off pump coronary artery bypass grafting (OPCAB) is claimed to reduce the operative morbidity and mortality in high risk patients. It was the aim of the study to compare the outcome of OPCAB patients classified as high- and low risk according to the EuroSCORE.

METHODS

Medical records of patients undergoing off pump coronary artery bypass grafting (n=126) at our institution between 1998 and 2001 were retrospectively reviewed. We classified them into two subgroups: low risk (EuroSCORE < or = 5, n=72, male 58 (81%), female 14 (19%), age 61 (37-78) years) and high risk (EuroSCORE >5, n=54, male 32 (59%), female 22 (41%), age 73 (42-83) years).

RESULTS

EuroSCORE high risk patients showed significantly higher rates of blood transfusion (70 vs 31%; P<0.0001), intraaortic balloon pump insertion (16 vs 3%; P=0.013), atrial fibrillation (43 vs 22%; P=0.014), and renal failure (13 vs 3%; P=0.028). ICU length of stay was significantly longer in the high risk group (25 vs 22 h; P=0.002). There was also a higher perioperative mortality in the high risk group (9 vs 0%; P=0.008).

CONCLUSION

From these data we conclude that using off pump coronary artery bypass grafting results as predicted by the EuroSCORE can be achieved. OPCAB is safe for low risk patients. Major complications seem to occur preferentially in the high risk group.

Is there still a need for living-related liver transplantation in children?

OBJECTIVE

To assess and compare the value of split-liver transplantation (SLT) and living-related liver transplantation (LRT).

SUMMARY BACKGROUND DATA

The concept of SLT results from the development of reduced-size transplantation. A further development of SLT, the in situ split technique, is derived from LRT, which itself marks the optimized outcome in terms of postoperative graft function and survival. The combination of SLT and LRT has abolished deaths on the waiting list, thus raising the question whether living donor liver transplantation is still necessary.

METHODS

Outcomes and postoperative liver function of 43 primary LRT patients were compared with those of 49 primary SLT patients (14 ex situ, 35 in situ) with known graft weight performed between April 1996 and December 2000. Survival rates were analyzed using the Kaplan-Meier method.

RESULTS

After a median follow-up of 35 months, actual patient survival rates were 82% in the SLT group and 88% in the LRT group. Actual graft survival rates were 76% and 81%, respectively. The incidence of primary nonfunction was 12% in the SLT group and 2.3% in the LRT group. Liver function parameters (prothrombin time, factor V, bilirubin clearance) and surgical complication rates did not differ significantly. In the SLT group, mean cold ischemic time was longer than in the LRT group. Serum values of alanine aminotransferase during the first postoperative week were significantly higher in the SLT group. In the LRT group, there were more grafts with signs of fatty degeneration than in the SLT group.

CONCLUSIONS

The short- and long-term outcomes after LRT and SLT did not differ significantly. To avoid the risk for the donor in LRT, SLT represents the first-line therapy in pediatric liver transplantation in countries where cadaveric organs are available. LRT provides a solution for urgent cases in which a cadaveric graft cannot be found in time or if the choice of the optimal time point for transplantation is vital.

The use of a high-volume screening procedure to assess the effects of dietary flavonoids on human cyp1a1 expression

We examined the effects of several agents, including dietary flavonoids, on CYP1A1 expression utilizing a recently developed high-throughput screening system for assessing human cytochrome P450 (CYP) induction. HepG2 cells, stably integrated with regulatory regions of human CYP1A1, were treated with resveratrol, apigenin, curcumin, kaempferol, green tea extract (GTE), (-)-epigallocatechin gallate (EGCG), quercetin, and naringenin. Of these flavonoids, resveratrol produced the greatest increase in CYP1A1-mediated luciferase activity (10-fold), whereas GTE, apigenin, curcumin, and kaempferol produced 2- to 3-fold increases in activity. Compared with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), omeprazole, or benzanthracene, where increases in luciferase activity ranged from 12- to 35-fold, these flavonoids exhibited weak agonist activity. The remaining compounds, EGCG, quercetin, and naringenin, produced negligible effects. Cotreatment of cells with TCDD and GTE, naringenin, and apigenin resulted in 58, 77, and 74% reductions, respectively, in TCDD-mediated CYP1A1 induction, indicating that these flavonoids exhibit potential antagonist activity toward the aryl hydrocarbon (Ah) receptor. Furthermore, results also suggest that GTE and apigenin possess Ah receptor antagonist and weak agonist activities. Thus, we have shown that a 96-well plate assay allowing high-throughput screening for P450 induction in less than 24 h was efficient in determining the effects of flavonoids on human CYP1A expression. Signal-to-noise ratios were low, and well-to-well and replicate variability was below 10%, allowing induction to be easily detected in this system. These features illustrate the reliability and feasibility of this high-volume screening system for identifying CYP inducers. Furthermore, results produced with the stable cell line were corroborated in HepG2 cells and primary cultures of human hepatocytes, suggesting that stably integrated cell lines harboring enhancer elements of P450 genes may be highly conducive to high-throughput screening.

Lethality-based selection of recombinant genes in mammalian cells: application to identifying tumor antigens

Many biological processes result in either cell death or cessation of cell growth. However, plasmid- and retrovirus-based mammalian expression vectors in which it has been possible to construct representative cDNA libraries cannot be readily recovered from cells that are not actively dividing. This has limited the efficiency of selection of recombinant genes that mediate either lytic events or growth arrest. Examples include genes that encode the target antigens of cytotoxic T cells, genes that promote stem-cell differentiation and pro-apoptotic genes. We have successfully constructed representative cDNA libraries in a poxvirus-based vector that can be recovered from cells that have undergone lethality-based selection. This strategy has been applied to selection of a gene that encodes a cytotoxic T-cell target antigen common to several independently derived tumors.

Deficiency of tumor necrosis factor alpha in a subclass of menstrual migraineurs

OBJECTIVE

The objective of this study was to determine whether differences in urinary proinflammatory cytokines, interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha), exist between migraineurs and nonheadache control subjects, and between nonhormonal migraine and menstrual migraine. Any differences noted would expand and clarify a neuroimmune hypothesis of migraine pathogenesis and lead to future diagnostic markers or therapeutic options or both for the disorder.

BACKGROUND

Current theories of migraine pathogenesis focus on biochemical abnormalities in the central nervous system resulting in sterile inflammation of meningeal blood vessels. Vasoactive substances involved in this process may include substance P, calcitonin gene-related peptide, neurokinin A, serotonin, and nitric oxide. Immune cell products, such as histamine, leukotrienes, and cytokines, also have vascular inflammatory properties.

METHODS

A study of proinflammatory cytokines, IL-1beta, IL-6, and TNF-alpha, was undertaken in menstrual migraineurs. During and outside of menses, 24-hour urine samples of 19 women with migraine were taken during a menstrual migraine, a nonmenstrual migraine, and a headache-free day, and compared with 24-hour urine samples taken of 10 nonheadache controls during and outside of menses.

RESULTS

A neuroimmune mechanism for migraine was tested with expected increases in proinflammatory cytokines tested during a migraine. This hypothesis was not validated. Mean IL-6 levels were increased in all three samples of migraineurs versus controls, but did not achieve statistical significance. No differences were found in IL-1beta levels between samples. Interestingly, marked differences were found in TNF-alpha values in menstrual migraineurs. Twelve (63%) of 19 migraineurs had at least one urine sample with undetectable TNF-alpha levels, whereas none of the 20 samples given by the 10 nonheadache controls in this study had undetectable levels. Thirty-two samples from men with cluster headache and nonheadache control subjects in prior studies had detectable levels.

CONCLUSIONS

This deficiency of TNF-alpha levels in women with migraine may signal a disordered neuroimmune communication network and predisposition to migraine.

Pharmacokinetics of SDZ RAD and cyclosporin including their metabolites in seven kidney graft patients after the first dose of SDZ RAD

AIMS

The aim of the study was to investigate the pharmacokinetics and metabolism of the new immunosuppressant SDZ RAD during concomitant therapy with cyclosporin in stable renal transplant patients. Furthermore, we studied the influence of SDZ RAD on the pharmacokinetics of cyclosporin at steady state levels.

METHODS

SDZ RAD was administered orally in different doses (0.25-15 mg day-1) to seven patients, who were on standard cyclosporin-based immunosuppression. The blood concentrations of both drugs including their main groups of metabolites were measured simultaneously by LC/electrospray-mass spectrometry.

RESULTS

The mean area under the blood concentration-time curve to 12 h (AUC(0,12 h)) was 4244 +/- 1311 microg l-1 h for cyclosporin before SDZ RAD treatment and 4683 +/- 1174 microg l-1 h (P = 0.106) on the day of SDZ RAD treatment (95% CI for difference -126, 1003). On both study days Cmax, and tmax of cyclosporin were not significantly different. The metabolite pattern of cyclosporin did not change. The pharmacokinetic data of SDZ RAD dose-normalized to 1 mg SDZ RAD were as follows: AUC(0,24 h): 35.4 +/- 13.1 microg l-1 h, Cmax: 7.9 +/- 2.7 microg l-1 and tmax: 1.5 +/- 0.9 h. The metabolites of SDZ RAD found in blood were hydroxy-SDZ RAD, dihydroxy-SDZ RAD, demethyl-SDZ RAD, and a ring-opened form of SDZ RAD.

CONCLUSIONS

A single dose of SDZ RAD did not influence significantly the pharmacokinetics of cyclosporin. The most important metabolite of SDZ RAD was the hydroxy-SDZ RAD, its AUC(0,24 h) being nearly half that of the parent compound SDZ RAD.

Increased prevalence of sensing types in men with cluster headaches

To ascertain whether the percentage of men who suffer with cluster headaches and are classified as sensing types according to Jung's theory of psychological types was comparable to the percentage (74%) of Sensing types that was found by Gallagher, et al. among women who experience migraine headaches, the Myers-Briggs Type Indicator was administered to 25 male cluster-headache patients. There were 19 (76%) male Sensing types, and this was comparable to the percentage of Sensing types for migrainous women. The results are discussed as supporting previous contentions that Sensing types may be prone to developing psychosomatic symptoms related to stress.

Psychologic aspects of chronic headache

Chronic recurrent headache affects 45 million Americans. Despite recent advances in medical modes of therapy for headache, the underlying pathophysiology for the condition is not yet fully understood. Like other conditions for which we have no objective markers for disease, nor a clear understanding of pathophysiology, psychologic causes are suspected. Although mounting evidence suggests a biochemical basis for headache, many clinicians still believe that psychologic influences may contribute to maintaining headache chronicity. Nonpharmacologic and psychologic treatment modalities such as biofeedback and cognitive/behavioral therapy may be successfully used as part of a comprehensive treatment program to give patients a greater sense of control, reverse anticipatory anxiety, and improve functioning and quality of life.

The incidence of ventilator-associated pneumonia and success in nutrient delivery with gastric versus small intestinal feeding: a randomized clinical trial

BACKGROUND

Enteral feeding provides nutrients for patients who require endotracheal tubes and mechanical ventilation. There is a presumed increase in the risk of ventilator-associated pneumonia (VAP) with tube feeding. This has stimulated the development of procedures for duodenal intubation and small intestinal (SI) feeding as primary prophylaxes to prevent VAP.

OBJECTIVE

To investigate the rate of VAP and adequacy of nutrient delivery with gastric (G) vs. SI feeding.

DESIGN

A prospective, randomized, controlled trial.

SETTING

A medical intensive care unit of a county hospital.

PATIENTS

A total of 44 endotracheally intubated, mechanically ventilated patients requiring enteral nutrition.

INTERVENTION

Subjects were randomized to receive enteral nutrition via G or SI feeding. Protocols directed the placement of the feeding tube and the infusion of enteral nutrition and defined the radiographic and clinical criteria for a diagnosis of VAP.

MEASUREMENTS AND OUTCOMES

The incidence of VAP and the adequacy of nutritional supplementation were prospectively followed. The relative risk of VAP with SI was 1.1 (95% confidence interval 0.96-2.44) compared with G. The SI group received a greater percentage of their caloric requirements (SI 69 +/- 7% vs. G 47 +/- 7%, mean +/- SEM, p < .05). Mortality did not differ between G (26 +/- 9%) and SI (24 +/- 10, p = .86).

CONCLUSIONS

There is no clear difference in the incidence of VAP in SI compared with G enteral nutrition. Patients given feeding into the SI do receive higher calorie and protein intakes.

Small volume flow probe for automated direct-injection NMR analysis: design and performance

A detailed characterization of an NMR flow probe for use in direct-injection sample analysis is presented. A 600-MHz, indirect detection NMR flow probe with a 120-microl active volume is evaluated in two configurations: first as a stand-alone small volume probe for the analysis of static, nonflowing solutions, and second as a component in an integrated liquids-handling system used for high-throughput NMR analysis. In the stand-alone mode, (1)H lineshape, sensitivity, radiofrequency (RF) homogeneity, and heat transfer characteristics are measured and compared to conventional-format NMR probes of related design. Commonly used descriptive terminology for the hardware, sample regions, and RF coils are reviewed or defined, and test procedures developed for flow probes are described. The flow probe displayed general performance that is competitive with standard probes. Key advantages of the flow probe include high molar sensitivity, ease of use in an automation setup, and superior reproducibility of magnetic field homogeneity which enables the practical implementation of 1D T2-edited analysis of protein-ligand interactions.