Desflurane Preconditioning Induces Time-dependent Activation of Protein Kinase C Epsilon and Extracellular Signal-regulated Kinase 1 and 2 in the Rat Heart In Vivo

Background: Activation of protein kinase C epsilon (PKC-[epsilon]) and extracellular signal-regulated kinase 1 and 2 (ERK1/2) are important for cardioprotection by preconditioning. The present study investigated the time dependency of PKC-[epsilon] and ERK1/2 activation during desflurane-induced preconditioning in the rat heart.

Methods: Anesthetized rats were subjected to regional myocardial ischemia and reperfusion, and infarct size was measured by triphenyltetrazoliumchloride staining (percentage of area at risk). In three groups, desflurane-induced preconditioning was induced by two 5-min periods of desflurane inhalation (1 minimal alveolar concentration), interspersed with two 10-min periods of washout. Three groups did not undergo desflurane-induced preconditioning. The rats received 0.9% saline, the PKC blocker calphostin C, or the ERK1/2 inhibitor PD98059 with or without desflurane preconditioning (each group, n = 7). Additional hearts were excised at four different time points with or without PKC or ERK1/2 blockade: without further treatment, after the first or the second period of desflurane-induced preconditioning, or at the end of the last washout phase (each time point, n = 4). Phosphorylated cytosolic PKC-[epsilon] and ERK1/2, and membrane translocation of PKC-[epsilon] were determined by Western blot analysis (average light intensity).

Results: Desflurane significantly reduced infarct size from 57.2 +/- 4.7% in controls to 35.2 +/- 16.7% (desflurane-induced preconditioning, mean +/- SD, P < 0.05). Both calphostin C and PD98059 abolished this effect (58.8 +/- 13.2% and 64.2 +/- 15.4% respectively, both P < 0.05 versus desflurane-induced preconditioning). Cytosolic phosphorylated PKC-[epsilon] reached its maximum after the second desflurane-induced preconditioning and returned to baseline after the last washout period. Both calphostin C and PD98059 inhibited PKC-[epsilon] activation. ERK1/2 phosphorylation reached its maximum after the first desflurane-induced preconditioning and returned to baseline after the last washout period. Calphostin C had no effect on ERK1/2 phosphorylation.     

Peroxide als Pflanzeninhaltsstoffe, 12. Mitt.: Peroxide vom Davanon-Typ aus der Eberraute (Artemisia abrotanum) und ihre Darstellung

Peroxides as Plant Constituents, XII: Davanone Type Peroxides from Artemisia abrotanum and Their Preparation From the aerial parts of Artemisia abrotanum L. (Asteraceae), besides (+)-Davanone ( 1 ) and Arteincultone ( 2 ), the known peroxy-semiketals 2 , 5 , and 7 were isolated. In addition, the previously unknown davanone type peroxides epi-arteincultone ( 4 ) and spiro-arteincultone ( 6 ) were identified in A. abrotanum by TLC. By means of singlet oxygen oxidation of 1 , compounds 2, 3, 4, 5 , and 7 are formed, by triplet oxygen oxydation compounds 2, 3, 5, 6, 7 as well as hydroxy-davanone.     

Multifocal motor neuropathy: Clinical and electrophysiological findings

Multifocal motor neuropathy (MMN) can be differentiated from motor neuron disease by electrophysiological evidence of conduction block. To increase the probability of recording conduction block, we studied the whole nerve length including proximal segments in 84 patients with pure motor syndromes, using a special stimulation technique. In 8 patients, the diagnosis of MMN was confirmed by electrophysiological evidence of conduction block or temporal dispersion. The typical clinical picture of MMN with chronic progressive, asymmetrical, marked distal weakness was observed in our patients. Electrophysiological routine tests of distal nerves were usually normal except in nerve segments with conduction block. In 4 patients, conduction block could be recorded only in proximal nerve segments or spinal roots. All patients showed rapid improvement of clinical features and parallel reduction of conduction block during or after highdose intravenous immunoglobulin (ivIG) therapy, supporting the diagnosis of an immune-mediated neuropathy. Three of them are now in remission without any therapy, whereas 5 still receive a regular ivIG course every 2-12 weeks as long-term treatment. In all patients with pure or predominantly motor syndromes and normal findings in electrophysiological routine tests of distal nerve segments, there should be proximal conduction block studies to avoid overlooking a treatable disorder such as MMN.     

Embryonic development and mitochondrial function

Cytochrome oxidase, which is partially synthesized by the mitochondrion, was used as a measure for the development of mitochondrial function in rat embryos during the late stage of organogenesis. For this purpose the specific inhibitor of mitochondrial protein synthesis, chloramphenicol (CAP), served as a tool. Due to the rapid elimination rate of CAP from rats, a method for continuous infusion which would not cause immobilization to the animals was devised. 1. Pharmacokinetic studies proved that CAP reaches the embryo before placentation. Concentrations of CAP in the embryo are as high as they are in the maternal serum (about 20 mug/ml serum or g embryo) and thuse are sufficiently in supply for the inhibition of mitochondrial proteins synthesis, if 1000 mg/kg CAP are infused intravenously per 24 hrs. CAP is partially excluded from the embryonic compartment after the placental barrier has fully developed: whereas CAP concentration in the maternal serum remains at about 20 mug/ml, the concentration in the embryonic compartment drops to about 10 mug/g embryonic tissue during day 13 of gestation. 2. The average cytochrome oxidase activity per cell is very low (about 1 nmole O2/min X mug DNA-1) in embryonic tissue as it is in many other rapidly proliferating tissues. It is 15-60 times higher in slowly proliferating tissues, as, for example, the adult rat liver or brain (greater than 14 nmoles O2/min X mug DNA-1). 3. When the infusion technique is applied on day 12 of gestation, a sufficiently high concentration of CAP in embryonic tissue can be obtained to inhibit the synthesis of cytochrome oxidase. In constrast to tissues of an adult organism-as in the case of liver after partial hepatectomy- in embryonic tissues this limitation in the availablity of cytochrome oxidase appearently results in a critical reduction of energy production, which subsequently affects the DNA synthesis and embryonic growth. 4. The possible relevance and applicability of these experimental findings to man is discussed.     

The influence of mitochondrial KATP-channels in the cardioprotection of preconditioning and postconditioning by sevoflurane in the rat in vivo

Volatile anesthetics induce myocardial preconditioning and can also protect the heart when given at the onset of reperfusion-a practice recently termed "postconditioning." We investigated the role of mitochondrial KATP (mKATP)-channels in sevoflurane-induced cardioprotection for both preconditioning and postconditioning alone and whether there is a synergistic effect of both. Rats were subjected to 25 min of coronary artery occlusion followed by 120 min of reperfusion. Infarct size was determined by triphenyltetrazolium staining. The following protocols were used: 1) preconditioning (S-Pre, n = 10, achieved by 2 periods of 5 min sevoflurane administration (1 MAC) followed by 10 min of washout); 2) sevoflurane postconditioning (1 MAC of sevoflurane given for 2 min at the beginning of reperfusion; S-Post, n = 10); 3) administration before and after ischemia (S-Pre + S-Post, n = 10). Protocols 1-3 were repeated in the presence of 5-hydroxydecanoate (5HD), a specific mKATP-channel-blocker (S-Pre + S-Post + 5HD, S-Pre + 5HD: n = 10; S-Post + 5HD: n = 9). Nine rats served as untreated controls (CON) or received 5HD alone (5HD, n = 10). Both S-Pre (23% +/- 13% of the area at risk, mean +/- sd) and S-Post (18% +/- 5%) reduced infarct size compared with CON (49% +/- 11%, both P < 0.05). S-Pre + S-Post resulted in a larger reduction of infarct size (12% +/- 5%, P = 0.054 versus S-Pre) compared with administration before or after ischemia alone. 5HD diminished the protection in all three sevoflurane treated groups (S-Pre + 5HD, 35% +/- 12%; S-Post + 5HD, 44% +/- 12%; S-Pre + S-Post + 5HD, 46% +/- 14%;) but given alone had no effect on infarct size (41% +/- 13%). Sevoflurane preconditioning and postconditioning protects against myocardial ischemia-reperfusion injury. The combination of preconditioning and postconditioning provides additive cardioprotection and is mediated, at least in part, by mKATP-channels.     

Delayed chemokine receptor 1 blockade prolongs survival in collagen 4A3-deficient mice with Alport disease

Human Alport disease is caused by a lack of the alpha3-, 4-, or 5-chain of type IV collagen (COL4A). Affected humans and COL4A3-deficient mice develop glomerulosclerosis and progressive renal fibrosis in the presence of interstitial macrophages, but their contribution to disease progression is under debate. This question was addressed by treating COL4A3-deficient mice with BX471, an antagonist of chemokine receptor 1 (CCR1) that is known to block interstitial leukocyte recruitment. Treatment with BX471 from weeks 6 to 10 of life improved survival of COL4A3-deficient mice, associated with less interstitial macrophages, apoptotic tubular epithelial cells, tubular atrophy, interstitial fibrosis, and less globally sclerotic glomeruli. BX471 reduced total renal Cll5 mRNA expression by reducing the number of interstitial CCL5-positive cells in inflammatory cell infiltrates. Intravital microscopy of the cremaster muscle in male mice identified that BX471 or lack of CCR1 impaired leukocyte adhesion to activated vascular endothelium and transendothelial leukocyte migration, whereas leukocyte rolling and interstitial migration were not affected. Furthermore, in activated murine macrophages, BX471 completely blocked CCL3-induced CCL5 production. Thus, CCR1-mediated recruitment and local activation of macrophages contribute to disease progression in COL4A3-deficient mice. These data identify CCR1 as a potential therapeutic target for Alport disease or other progressive nephropathies associated with interstitial macrophage infiltrates.     

Immunophenotypic and genetic characterization of a CD8 positive mantle cell lymphoma in a patient with concomitant Mycosis fungoides

Mantle cell lymphoma (MCL) is immunophenotypically characterized by cell surface co-expression of CD19, CD20, CD5, IgM and FMC7. However, the concomitant presence of other antigens distinctive of a particular leukocyte subset, e.g. T-lymphocytes, is an exceptional finding in MCL. Here, the first case of a blastic MCL in leukaemic phase with aberrant expression of the T-cell associated antigen CD8 occurring in a patient with concomitant Mycosis fungoides is described. Comprehensive immunophenotypic analysis showed that the MCL cells expressed the typical B-lymphocytic markers, were CD5 and CD8 positive, but did not express other T-cell proteins, such as CD2, CD3, CD4, CD7, TCRalphabeta and TCRgammadelta. The MCL cells expressed both CD8alpha and CD8beta chains indicating cell surface presence of CD8alphabeta heterodimers. Intriguingly, expression of the cytotoxic enzymes perforin and granzyme A was detected by RT-PCR. Cytogenetic and molecular genetic analysis of the lymphoma cells confirmed cyclin D1 overexpression secondary to the t(11;14)(q13;32) chromosomal translocation. Furthermore, trisomy 11, trisomy 14 and extra copies of t(11;14) translocated chromosomes were detected in sub clones of the analyzed MCL cells. Clinically, an aggressive course of disease including cerebral lymphoma involvement was noted in the reported patient. Hence, systematic studies addressing the incidence, biology and clinical behavior of this form of MCL seem to be justified in future.     

Exercise training raises daily activity stronger than predicted from exercise capacity in patients with COPD

The 6-min walking (6MWD) and 6-min treadmill distance (6MTD) are often used as measures of exercise performance in patients with COPD. The aim of our study was to assess their relationship to daily activity in the course of an exercise training program. Eighty-eight patients with stable COPD (71m/17f; mean +/- SD age, 60 +/-8 year; FEV1, 43+/-14% pred) were recruited, 66 of whom performed a hospital-based 10-day walking training, whereas 22 were treated as control. On day 16MTD, and on days 8 and 10, 6MTD and 6MWD were determined. In addition, patients used an accelerometer (TriTrac-R3D) to record 24 h-activity, whereby training sessions were excluded. In both groups there was a linear relationship (r > or = 0.84 and P < 0.0001) between 6MTD and 24 h-activity, the slope of which was 2.5-fold greater in the training group (P < 0.01). Similar relationships emerged for 6MWD. There was no association between baseline 6MTD, FEV1 or BMI and any of the other measures. These data suggest that daily activity did not markedly vary with exercise capacity under baseline conditions. Participation in a training program increased activity significantly stronger than predicted from the gain in exercise capacity. This underlines the importance of non-physiological, patient-centered factors associated with training in COPD.