[Targeted treatment of posttraumatic disorders-what can confrontation therapy achieve?] / Zielgerichtete Behandlung von Traumafolgestörungen ­ was kann eine konfrontative Therapie leisten?

Confrontation with aversive trauma symptoms is a key element in the treatment of stress-associated disorders, especially posttraumatic stress disorder. It is aimed at working through and reattributing aversive memories and situations. Various techniques enable confrontation in sensu (i.e. imagined) and in vivo (in reality). Confrontation techniques are highly effective; however, since there is a risk of temporarily enhanced, possibly previously suppressed traumatic memories, confrontation must be carefully prepared and revised.

Intranasal oxytocin reduces provoked symptoms in female patients with posttraumatic stress disorder despite exerting sympathomimetic and positive chronotropic effects in a randomized controlled trial.

BACKGROUND: Posttraumatic stress disorder (PTSD) is a severe psychiatric disease accompanied by neuroendocrine changes such as adrenergic overdrive and hence an elevated cardiovascular morbidity. Current pharmacotherapeutic options for PTSD are less than suboptimal, necessitating the development of PTSD-specific drugs. Although the neuropeptide oxytocin has been repeatedly suggested to be effective in PTSD treatment, there are, to our knowledge, only three studies that have assessed its efficacy on the intensity of PTSD symptoms in PTSD patients - among them one symptom provocation study in male veterans. METHODS: To evaluate for the first time how oxytocin influences the intensity of provoked PTSD symptoms and, furthermore, cardiac control in female PTSD patients, we assessed their psychic and cardiac response to trauma-script exposure with and without oxytocin pretreatment in a double-blind randomized placebo-controlled study. We used a within-subject design to study 35 female PTSD patients who received oxytocin and placebo in a 2-week interval. Furthermore, we performed a small pilot study to get an idea of the relation of the stress-modulated endogenous oxytocin levels and heart rate - we correlated oxytocin serum levels with the heart rate of 10 healthy individuals before and after exposure to the Trier Social Stress Test (TSST). RESULTS: Intranasal oxytocin treatment was followed by a reduction of provoked total PTSD symptoms, in particular of avoidance, and by an elevation in baseline and maximum heart rate together with a drop in the pre-ejection period, a marker for sympathetic cardiac control. Furthermore, we found a positive correlation between endogenous oxytocin levels and heart rate both before and after TSST challenge in healthy control subjects. CONCLUSIONS: This study provides the first evidence that oxytocin treatment reduces the intensity of provoked PTSD symptoms in female PTSD patients. The small size of both samples and the heterogeneity of the patient sample restrict the generalizability of our findings. Future studies have to explore the gender dependency and the tolerability of the oxytocin-mediated increase in heart rate. This randomized controlled trial was retrospectively registered at the German Trials Register (DRKS00009399) on the 02 October 2015.

Signal-to-noise ratio of a mouse brain (13) C CryoProbe™ system in comparison with room temperature coils: spectroscopic phantom and in vivo results.

MRI and MRS in small rodents demand very high sensitivity. Cryogenic transmit/receive radiofrequency probes (CryoProbes) designed for (1) H MRI of mouse brain provide an attractive option for increasing the performance of small-animal MR systems. As the Larmor frequency of (13) C nuclei is four times lower than that for (1) H nuclei, an even larger sensitivity improvement is expected for (13) C applications. The aim of this work was to evaluate the performance of a prototype (13) C CryoProbe™ for mouse brain MRS. To investigate the possible gain of the (13) C CryoProbe™, we acquired localized single-voxel (13) C spectra and chemical shift images of a dimethyl sulfoxide phantom with the CryoProbe™, as well as with two room temperature resonators. The cryogenically cooled resonator achieved approximately four-fold higher signal-to-noise ratio in phantom tests when compared with the best-performing room temperature coil. In addition, we present localized (13) C spectra of mouse brain obtained with the CryoProbe™, as well as with one of the room temperature coils, demonstrating the performance in vivo. In summary, the cryogenic cooling technique significantly enhances the (13) C signal sensitivity at 9.4 T and enables the investigation of metabolism within mouse brain.

Absence of changes in GABA concentrations with age and gender in the human anterior cingulate cortex: a MEGA-PRESS study with symmetric editing pulse frequencies for macromolecule suppression.

Despite MEGA-PRESS being a robust method for editing the GABA resonance, there are macromolecule resonances at the same chemical shift that are coedited with this sequence. Although this is a known problem, it is still often overlooked. We aimed to evaluate the amount of macromolecule signal coedited, as well as the gender and age dependencies for the GABA resonance at 3.01 ppm using MEGA-PRESS with two different editing pulse frequencies. Forty-five healthy subjects (21-52 years) were included in an in vivo single voxel MEGA-PRESS study at 3.0 T. Phantom measurements were conducted to measure the signal loss when switching the editing pulse between 1.5 and 1.9 ppm instead of the mostly used switching between 1.9 and 7.5 ppm. The in vivo GABA signal detected by switching the editing pulse frequencies between 1.5 and 1.9 ppm was only 50% of the mean GABA detected by switching the editing pulse frequencies between 1.9 and 7.5 ppm. No gender differences were detected. A small age dependency was observed for GABA plus macromolecules, but not for GABA, suggesting an age-dependent macromolecule increase.

[Trauma-related disorders in patients with borderline personality disorders. Results of a multicenter study]. / Traumafolgestörungen bei Patienten mit Borderline-Persönlichkeitsstörung : Ergebnisse einer Multicenterstudie.

BACKGROUND: There is current controversy about the diagnostic overlap between personality disorders and trauma-related disorders. PATIENTS AND METHODS: Applying a multicenter study design, trauma-related disorders were investigated via interview assessment in 136 patients with borderline personality disorder (BPD) in 5 specialized treatment centers. Additionally a spectrum of psychological symptoms and prevalence of lifetime traumatic experiences were assessed by questionnaire measures. RESULTS: Diagnostic overlap between BPD and PTSD was found to be high (79%) as well as the overlap of BPD with complex PTSD (55%) and severe dissociative disorders (41%). Including neglect and emotional violence as trauma categories, an extremely high prevalence of lifetime traumatic experiences was reported (96%). Experiences of sexual violence were reported by 48% of all female and 28% of all male patients. Severe forms of physical violence were reported by 65% of all patients. CONCLUSIONS: BPD patients with severe psychopathology show a high comorbidity with trauma-related disorders including dissociative disorders. This association has to be taken into account when planning psychological treatment.

Predictors of complex PTSD: the role of trauma characteristics, dissociation, and comorbid psychopathology.

BACKGROUND: Complex Posttraumatic Stress Disorder (CPTSD) has previously been associated with earlier trauma onset, repeated interpersonal traumatization, more dissociation, and more comorbid psychopathology. However, it is still debated if the afore-mentioned risk factors are related to CPTSD diagnosis or rather indicative of a more severe form of post-traumatic distress. The aim of this study was to compare patients with a CPTSD diagnosis to those with PTSD in trauma characteristics (onset, chronicity, interpersonal nature, familiarity with perpetrator), dissociation, and psychiatric comorbidities, while accounting for symptom severity. METHODS: In total, N = 81 patients with a trauma history (n = 43 with CPTSD; n = 37 with PTSD) underwent diagnostic interviews by trained clinicians and completed measures on CPTSD symptom severity, trauma characteristics, and dissociation (Screening for Complex PTSD; Dissociative Experience Scale Taxon). RESULTS: Patients with CPTSD reported earlier onset of trauma, more trauma perpetrated by acquaintances or family members, and more comorbidities than those with PTSD, also when accounting for symptom severity. No group differences in chronicity and dissociation were found. Severity of CPTSD was associated with earlier onset, familiarity with perpetrator, more comorbid (affective) disorders, and dissociation in both diagnostic groups. CONCLUSION: Findings largely confirm earlier research, suggesting that CPTSD is associated with traumatic events that start earlier in life and are perpetrated by acquaintances. Focusing on transdiagnostic symptoms, such as dissociation, may help to detain symptom deterioration. Due to the small sample size, findings need to be interpreted with caution and further research is needed to replicate findings in larger samples. Future research should also elucidate possible working mechanisms besides dissociation, such as emotion dysregulation or negative self-image.

Brief psychodynamic interpersonal psychotherapy for patients with multisomatoform disorder: randomised controlled trial.

BACKGROUND: Multisomatoform disorder is characterised by severe and disabling bodily symptoms, and pain is one of the most common and impairing of these. Furthermore, these bodily symptoms cannot be explained by an underlying organic disorder. Patients with multisomatoform disorder are commonly found at all levels of healthcare and are typically difficult to treat for physicians as well as for mental health specialists. AIMS: To test whether brief psychodynamic interpersonal therapy (PIT) effectively improves the physical quality of life in patients who have had multisomatoform disorder for at least 2 years. METHOD: We recruited 211 patients (from six German academic outpatient centres) who met the criteria for multisomatoform disorder for a randomised, controlled, 12-week, parallelgroup trial from 1 July 2006 to 1 January 2009 (International Standard Randomised Controlled Trial Number ISRCTN23215121). We randomly assigned the patients to receive either 12 weekly sessions of PIT (n = 107) or three sessions of enhanced medical care (EMC, n = 104). The physical component summary of the Short Form Health Survey (SF-36) was the pre-specified primary outcome at a 9-month follow-up. RESULTS: Psychodynamic interpersonal therapy improved patients' physical quality of life at follow-up better than EMC (mean improvement in SF-36 score: PIT 5.3, EMC 2.2), with a small to medium between-group effect size (d = 0.42, 95% CI 0.15-0.69, P = 0.001). We also observed a significant improvement in somatisation but not in depression, health anxiety or healthcare utilisation. CONCLUSIONS: This trial documents the long-term efficacy of brief PIT for improving the physical quality of life in patients with multiple, difficult-to-treat, medically unexplained symptoms.

[Development and validation of an inventory of ego functions and self regulation (Hannover Self-Regulation Inventory, HSRI)]. / Entwicklung und Validierung eines Fragebogens zu Ich-Funktionen und zur Selbstregulationsfähigkeit (Hannover-Selbstregulations-Inventar, HSRI).

OBJECTIVE: The aim of this study was to construct and validate a short self-rating questionnaire for the assessment of ego functions and ability of self regulation. MATERIAL AND METHODS: An item pool of 120 items covering 6 postulated dimensions was reduced by two steps in independent samples (n = 136 + 470) via factor and item analyses to the final version consisting of 35 items. RESULTS: The 5 resulting questionnaire scales "interpersonal disturbances", "frustration tolerance and impulse control", "identity disturbances", "affect differentiation and affect tolerance" and "self-esteem" were well interpretable and showed in confirmatory factor analysis the best fit to the data (CHI²/df = 3.48; RMSEA = 0.73). Total scores were found to differentiate well between diagnostic groups of patients with more or less ego pathology (FANOVA = 9.8; df = 11; p < 0.001), thus proving good concurrent validity. Reliability was shown by testing internal consistency and test-retest correlations. CONCLUSION: The "Hannover self-regulation questionnaire" (HSRQ) evidently is an appropriate and reliable screening instrument in order to assess ego functions and capacities of self regulation in an economic and user-friendly means. The scale structure allows differentiated diagnostics of weak vs. stable ego functions and may be used for detailed therapy planning.

Affinity purification of a framework 1 engineered mouse/human chimeric IgA2 antibody from tobacco.

Complex multimeric proteins such as dimeric and secretory immunoglobulin A (IgA) can be difficult to produce in heterologous systems, although this has been achieved using several platforms including plants. As well as topical mucosal applications, dimeric IgA (dIgA), and secretory IgA (sIgA) can be used in tumor and anti-viral therapy, where their more potent cell-killing properties may increase their efficacy compared to current drugs based on IgG. However, the development of therapeutic IgA formats is hampered by the need to co-express four different polypeptides, and the inability to purify such molecules using conventional protein A or protein G affinity chromatography. The light chain (LC)-specific affinity ligand protein L is a potential alternative, but it only recognizes certain kappa light chain (LC(κ)) subtypes. To overcome these limitations, we have adapted a framework-grafting approach to introduce LCs that bind protein L into any IgA. As a model, we used the chimeric anti-human chorionic gonadotropin (hCG) antibody cPIPP, since this contains a murine LC((κ)) subtype that does not bind protein L. Grafting was achieved by replacing selected framework region 1 (FR1) residues in the cPIPP LC(κ) variable domain with corresponding residues from LC(κ) subtypes that can bind protein L. The grafted antibody variants were successfully purified by protein L affinity chromatography. These modifications affected neither their antigen-binding properties nor the yields achieved by transient expression in tobacco plants. Our results therefore show that LC FR1 grafting can be used as generic strategy for the purification of IgA molecules.

Optimal nitrogen supply as a key to increased and sustained production of a monoclonal full-size antibody in BY-2 suspension culture.

Plant cell cultures have been used as expression hosts for recombinant proteins for over two decades. The quality of plant cell culture-produced proteins such as full-size monoclonal antibodies has been shown to be excellent in terms of protein folding and binding activity, but the productivity and yield fell short of what was achieved using mammalian cell culture, in which the key to gram-per-liter expression levels was strain selection and medium/process optimization. We carried out an extensive media analysis and optimization for the production of the full-size human anti-HIV antibody 2G12 in N. tabacum cv. BY-2. Nitrogen source and availability was found to be one key factor for the volumetric productivity of plant cell cultures. Increased amounts of nitrate in the culture medium had a dramatic impact on protein yields, resulting in a 10-20-fold increase in product accumulation through a combination of enhanced secretion and higher stability. The results were scalable from shake flasks to stirred-tank bioreactors, where the maximum yield per cultivation volume was 8 mg L(-1) over 7 days. During the stationary phase, antibody levels were 150-fold higher in nitrogen-enriched medium compared to standard medium. The enhanced medium appeared not to affect antibody quality and activity, as determined by Western blots, surface plasmon resonance binding assays and N-glycan analysis.

The affinity of antipsychotic drugs to dopamine and serotonin 5-HT2 receptors determines their effects on prefrontal-striatal functional connectivity.

One of the major challenges of cross-species translation in psychiatry is the identification of quantifiable brain phenotypes linked to drug efficacy and/or side effects. A measure that has received increasing interest is the effect of antipsychotic drugs on resting-state functional connectivity (FC) in magnetic resonance imaging. However, quantitative comparisons of antipsychotic drug-induced alterations of FC patterns are missing. Consideration of receptor binding affinities provides a means for the effects of antipsychotic drugs on extended brain networks to be related directly to their molecular mechanism of action. Therefore, we examined the relationship between the affinities of three second-generation antipsychotics (amisulpride, risperidone and olanzapine) to dopamine and serotonin receptors and FC patterns related to the prefrontal cortex (PFC) and striatum in Sprague-Dawley rats. FC of the relevant regions was quantified by correlation coefficients and local network properties. Each drug group (32 animals per group) was subdivided into three dose groups and a vehicle control group. A linear relationship was discovered for the mid-dose of antipsychotic compounds, with stronger affinity to serotonin 5-HT2A, 5-HT2C and 5-HT1A receptors and decreased affinity to D3 receptors associated with increased prefrontal-striatal FC (p = 0.0004, r²â€¯= 0.46; p = 0.004, r²â€¯= 0.33; p = 0.002, r²â€¯= 0.37; p = 0.02, r²â€¯= 0.22, respectively). Interestingly, no correlation was observed for the low and high dose groups, and for D2 receptors. Our results indicate that drug-induced FC patterns may be linked to antipsychotic mechanism of action on the molecular level and suggest the technique's value for drug development, especially if our results are extended to a larger number of antipsychotics.

Enhanced angiotensin II activity in heart failure: reevaluation of the counterregulatory hypothesis of receptor subtypes.

There are strong data favoring the pathogenic role of angiotensin II type 1 receptor (AT(1)) activation with subsequent promotion of myocyte growth and cardiac fibrosis in the development of cardiac hypertrophy and heart failure. An emerging hypothesis suggests that the activity of the angiotensin II type 2 receptor (AT(2)) may counterregulate AT(1) receptor effects during cardiac development and during the evolution of cardiac hypertrophy and heart failure. In this review, we examine the potential role of AT(2) activity in the context of this hypothesis. In contrast to the counterregulatory hypothesis, studies in mice with an overabundance of, or a deficiency in, the AT(2) receptor do not suggest that AT(2) signaling is essential for cardiac development. Moreover, the proposed antigrowth effects of AT(2) receptor signaling in pathological cardiac hypertrophy could not be shown in two mice models both deficient in AT(2) receptors. The role of AT(2) receptor signaling in cardiac fibrosis is, however, still debatable because of conflicting data in the same two studies. In angiotensin II-evoked apoptosis in cardiomyocytes, the proposed proapoptotic role of AT(2) activity could not be confirmed. Furthermore, in the progression from the bench to bedside, the results of two large clinical trials in heart failure, namely ELITE II and Val-HeFT, can be explained without ascribing a major protective role to the unopposed activity of the AT(2) receptor in the failing myocardium. In this review, we conclude that the collective evidence does not strongly support a net beneficial effect of AT(2) stimulation in the diseased myocardium.

Myocardial protection by insulin at reperfusion requires early administration and is mediated via Akt and p70s6 kinase cell-survival signaling.

The "metabolic cocktail" comprising glucose-insulin-potassium administrated at reperfusion reduces infarct size in the in vivo rat heart. We propose that insulin is the major component mediating this protection and acts via Akt prosurvival signaling. This hypothesis was studied in isolated perfused rat hearts (measuring infarct size to area of risk [%]) subjected to 35 minutes regional myocardial ischemia and 2 hours reperfusion. Insulin administered at the onset of reperfusion attenuated infarct size by >/=45% versus control hearts (P<0.001). Insulin-mediated cardioprotection was found to be independent of the presence of glucose at reperfusion. Moreover, the cell survival benefit of insulin is temporally dependent, in that insulin administration from the onset of reperfusion and maintained for either 15 minutes or for the duration of reperfusion reduced infarct size. In contrast, protection was abrogated if insulin administration was delayed until 15 minutes into reperfusion. Pharmacological inhibition of both upstream and downstream signals in the Akt prosurvival pathway abolished the cardioprotective effects of insulin. Here coadministration of insulin with the tyrosine kinase inhibitor lavendustin A, the phosphatidylinositol3-kinase (PI3-kinase) inhibitor wortmannin, and mTOR/p70s6 kinase inhibitor rapamycin abolished cardioprotection. Steady-state levels of activated/phosphorylated Akt correlated with insulin administration. Finally, downstream prosurvival targets of Akt including p70s6 kinase and BAD were modulated by insulin. In conclusion, insulin administration at reperfusion reduces myocardial infarction, is dependent on early administration during reperfusion, and is mediated via Akt and p70s6 kinase dependent signaling pathway. Moreover, BAD is maintained in its inert phosphorylated state in response to insulin therapy.

Ischemic and pharmacological preconditioning in Girardi cells and C2C12 myotubes induce mitochondrial uncoupling.

Pharmacological uncoupling of mitochondrial oxidation from phosphorylation promotes preconditioning-like cardioprotection in the isolated rat heart. We hypothesized that modest mitochondrial uncoupling may be a critical cellular event in orchestrating preconditioning. Human-derived Girardi cells and murine C2C12 skeletal myotubes were preconditioned using simulated ischemia, adenosine, and diazoxide. Cell viability after 6 hours of simulated ischemia was measured using lactate dehydrogenase release and propidium iodide uptake. Mitochondrial inner membrane potential (DeltaPsim) was investigated by flow cytometry, cellular ATP by recombinant firefly-luciferase bioluminescence, and cellular oxygen consumption using oximetry. Preconditioning enhanced cell viability with attenuation of lactate dehydrogenase release (>/=30%, P<0.05 versus ischemic controls) and a reduction in propidium iodide uptake by >/=26% versus ischemic controls after simulated ischemia in both cell lines. In Girardi cells, preconditioning induced the following phenotype immediately before index ischemia: (1) decreased DeltaPsim (JC-1: simulated ischemia 90+/-3%, adenosine 82+/-7%, diazoxide 87+/-4%, versus control 100%, P<0.05); (2) attenuation in cellular ATP levels (CTL 0.21+/-0.03 nmol/L ATP/microg protein, simulated ischemia 0.12+/-0.02, adenosine 0.15+/-0.02, diazoxide 0.11+/-0.02, P<0.05); and (3) enhanced cellular oxygen consumption (control 2.3+/-0.1 nmol/L oxygen/min/1x10(6) cells, simulated ischemia 3.1+/-0.1, adenosine 3.1+/-0.3, diazoxide 2.6+/-0.2, P<0.05). Cytoprotection, mitochondrial depolarization, and enhanced oxygen consumption were attenuated by the putative mitochondrial K(ATP)-channel antagonist 5-hydroxydecanoate. The uncoupled phenotype in response to preconditioning was similarly observed in C2C12 myotubes. The present study suggests that modest mitochondrial uncoupling represents a unifying cellular response which may be important in directing preconditioning-mediated cytoprotection.

Delta opioid receptor stimulation mimics ischemic preconditioning in human heart muscle.

OBJECTIVES: The objective of this study was to examine whether the delta (delta) opioid receptor isoform is expressed in the human heart and whether this receptor improves contractile function after hypoxic/reoxygenation injury. BACKGROUND: Delta opioid receptor agonists mimic preconditioning (PC) in rat myocardium, corresponding to known cardiac delta opioid receptor expression in this species. METHODS: The messenger RNA transcript encoding the delta opioid receptor was identified in human atria and ventricles. To evaluate the cardioprotective role of the opioid receptor, human atrial trabeculae from patients undergoing coronary bypass grafting were isolated and superfused with Tyrode's solution. A control group underwent 90 min of simulated ischemia and 120 min of reoxygenation. A second group was preconditioned with 3 min simulated ischemia and 7 min reoxygenation. Additional groups included: superfusion with the delta receptor agonist (DADLE) (10 nM), with the delta receptor antagonist naltrindole (10 nM) and with the mitochondrial K(ATP) channel blocker 5-hydroxydecanoate (5HD) (100 microM) either with or without PC, respectively. A final group was superfused with 5HD before DADLE. The end point used was percentage of developed force after 120 min of reoxygenation. RESULTS: Results, expressed as means +/- SEM, were: control = 32.6 + 3.8%; PC = 50.5% + 1.8*; DADLE = 46.0+/-3.9%*; PC + naltrindole = 25.5+/-3.9%; naltrindole alone = 25.5+/-4.3%; 5HD + PC = 28.9+/-7.4%; 5HD alone = 24.1+/-3.0%; 5HD + DADLE = 26.9+/-4.4% (*p < 0.001 vs. controls). CONCLUSIONS: Human myocardium expresses the delta opioid receptor transcript. Stimulation of this receptor appears to protects human muscle from simulated ischemia, similar to PC, and via opening of the mitochondrial K(ATP) channel.

Effect of antioxidant vitamins on low density lipoprotein oxidation and impaired endothelium-dependent vasodilation in patients with hypercholesterolemia.

OBJECTIVES: The aims of this study were to determine whether antioxidant vitamins could reduce the susceptibility of low density lipoprotein (LDL) to oxidation and improve endothelium-dependent vasodilator responsiveness in patients with hypercholesterolemia. BACKGROUND: Animals and humans with hypercholesterolemia have exhibited impaired endothelium-dependent vasodilation. In vitro studies suggest that oxidatively modified LDL can impair nitric oxide production. METHODS: Forearm blood flow was measured with strain gauge plethysmography and brachial artery drug infusions in 19 patients, aged 52 +/- 9 years, with hypercholesterolemia (mean +/- SD total cholesterol 283 +/- 22 mg/dl, LDL 197 +/- 31 mg/dl) and in 14 subjects, aged 48 +/- 8 years, with normal cholesterol levels (total cholesterol 169 +/- 20 mg/dl, LDL 102 +/- 25 mg/dl). Acetylcholine (7.5, 15 and 30 micrograms/min) was utilized as an endothelium-dependent vasodilator, and sodium nitroprusside (0.8, 1.6 and 3.2 micrograms/min) was used to test endothelium-independent vasodilation. Oxidative susceptibility of LDL was measured by a spectrophotometric assay of conjugated diene production after the addition of copper chloride. Hypercholesterolemic patients then received daily antioxidant vitamin supplements (beta-carotene [30 mg], ascorbic acid [vitamin C] [1,000 mg], vitamin E [800 IU]) for 1 month, with repeat measurement of both forearm blood flow responsiveness to the same agonists and LDL oxidizability. RESULTS: The maximal flow in response to acetylcholine was impaired in patients compared with that in normal subjects (9.8 +/- 7.8 vs. 15.9 +/- 8.1 ml/min per 100 ml, p = 0.03), with similar maximal flow responses to sodium nitroprusside (9.5 +/- 4.2 vs. 9.0 +/- 2.8 ml/min per 100 ml, p = 0.72). After 1 month of vitamin therapy, the onset of LDL oxidation was prolonged over baseline measurements by 71 +/- 67%, and the maximal rate of oxidation was decreased by 26 +/- 25% (both p < 0.001). However, the maximal forearm blood flow response to acetylcholine remained unchanged from baseline values (maximal flow after acetylcholine 9.0 +/- 6.2 vs. 9.8 +/- 7.8 ml/min per 100 ml, p = 0.57). This study had 80% power (alpha = 0.05) to exclude a 45% increase over baseline value in acetylcholine-stimulated flow during vitamin therapy. CONCLUSIONS: Although 1 month of administration of antioxidant vitamin supplements in hypercholesterolemic patients reduced the susceptibility of LDL to oxidation, impairment in endothelial function remained unaltered. The use of nonvitamin antioxidants or concomitant reduction in LDL levels, as well as more sensitive techniques for measuring vascular responsiveness, may be required to show a beneficial effect on endothelial vasodilator function.

Recent progress in plantibody technology.

Antibodies are an important class of proteins that can be used for the prevention, treatment and diagnosis of many diseases. Consequently, there is an intense and growing demand for recombinant antibodies, placing immense pressure on current production capacity which is based largely on microbial cultures and mammalian cells. Alternative systems for cost effective antibody production would be very welcome, and plants are now gaining widespread acceptance as green bioreactors with advantages in terms of cost, scalability and safety. Several plant-produced antibodies (plantibodies) are undergoing clinical trials and the first commercial approval could be only a few years away. The performance of the first generation of products has been very encouraging so far. In terms of product authenticity, differences in glycosylation between plantibodies and their mammalian counterparts have been defined, and the scientific evaluation of any possible consequences is underway. Ongoing studies are addressing the remaining biochemical constraints, and aim to further improve product yields, homogeneity and authenticity, particularly where the antibody is intended for injection into human patients. A remaining practical challenge is the implementation of large-scale production and processing under good manufacturing practice conditions that are yet to be endorsed by regulatory bodies. The current regulatory uncertainty and the associated costs represent an entry barrier for the pharmaceutical industry. However, the favourable properties of plants are likely to make the plant systems a useful alternative for small, medium and large scale production throughout the development of new antibody-based pharmaceuticals.

Dinitrophenol, cyclosporin A, and trimetazidine modulate preconditioning in the isolated rat heart: support for a mitochondrial role in cardioprotection.

BACKGROUND: Recent studies have postulated that mitochondrial ATP-sensitive potassium (mitoK(ATP)) channel activation may modulate mitochondrial function with the resultant induction of a preconditioning phenotype in the heart. We hypothesized that the modulation of mitochondrial homeostasis might confer preconditioning-like cardioprotection. METHODS: We used a model of regional ischemia in Langendorff-perfused isolated rat hearts. Short-term administration of 2,4-dinitrophenol (DNP), an uncoupler of oxidative phosphorylation and cyclosporin A (CSA), an inhibitor of mitochondrial respiration, was used in an attempt to elicit preconditioning-like cardioprotection. The anti-ischemic drug trimetazidine, known to attenuate CSA-induced disruption in mitochondrial function, and the mitoK(ATP) channel blocker 5-hydroxydecanoic acid (5-HD) were used to inhibit the effects of DNP and CSA. Finally, we studied the effect of trimetazidine on adenosine-induced and ischemic preconditioning. Risk zone and infarct size were measured and expressed as a percentage of the risk zone (I/R ratio). RESULTS: DNP, CSA and adenosine pretreatment reduced infarct size (I/R ratio: DNP 9.0+/-2.4%, CSA 12.5+/-1.4%, adenosine 11.9+/-3.6%, all P<0.001 vs. control, 30.2+/-1.3%) similarly to ischemic preconditioning (9.5+/-0.6%, P<0.001 vs. control). Trimetazidine limited the effect of ischemic preconditioning (22.2+/-2.0%, P<0.001 vs. ischemic preconditioning) and completely reversed the DNP, CSA, and the adenosine-mediated reduction in infarct size. 5-HD abolished the effect of ischemic preconditioning and CSA. CONCLUSION: DNP and CSA trigger preconditioning-like cardioprotection in the isolated rat heart. Trimetazidine, a known mitochondrial 'protector', attenuated both drug-induced and ischemic preconditioning. These data support the hypothesis that modulation of mitochondrial homeostasis may be a common downstream cellular event linking different triggers of preconditioning.

Risk factors for thyroid abnormalities after neck irradiation for childhood cancer.

Thyroid evaluations were performed in 95 patients who received radiotherapy to the neck region for childhood cancer five to 34 years earlier. Fifty-six patients (61 percent) had at least one abnormality of serum free thyroxine index, serum thyroid-stimulating hormone (thyrotropin), or thyroid palpation. Seven had subnormal free thyroxine index and 40 had elevated thyrotropin concentrations. Thyroidal radiation doses of 3,000 or more rads and lymphangiography independently increased the risk (p less than or equal to 0.01) of an elevated serum thyrotropin concentration (present in 11 percent of patients with neither risk factor, 50 percent of those who underwent lymphangiography and received less than 3,000 rads, 46 percent of those who had 3,000 or more rads and no lymphangiography, and 76 percent of those with both), but duration of follow-up did not. Twenty-six patients had thyroid nodules and six others had diffuse thyroid enlargement. The frequency of palpable abnormalities increased with the follow-up time after radiation (30 percent of patients followed up less than 10 years had abnormalities versus 43 percent of those followed up 10 or more years, p = 0.03), but was not related to the serum thyrotropin level, radiation dose, or lymphangiography. Among 10 patients who had surgery for nodules, three had localized papillary thyroid carcinomas.

Renal transplantation despite a positive antiglobulin crossmatch with and without prophylactic OKT3.

The antiglobulin crossmatch (AGXM) is a sensitive technique employed by many transplant centers to enhance detection of preformed antibody to donor antigens that may cause hyperacute rejection. However, positive AGXM may detect irrelevant or very low titers of anti-HLA antibody precluding transplantation in suitable recipients. To investigate the significance of a positive AGXM, cadaveric renal transplantation was carried out despite a weakly positive AGXM (defined as cell killing above background but not greater than 20%) in 48 recipients. In an initial group (n = 10), maintained on triple therapy (cyclosporine, azathioprine, and prednisone), accelerated acute rejection occurred in 4 recipients and 3 grafts were lost. A subsequent group (n = 38) was treated with a prophylactic course of OKT3 then triple therapy. There were no episodes of accelerated acute rejection (P less than 0.01) although clinical hyperacute rejection claimed one graft and the incidence of delayed graft function was high (75%). The prophylactic OKT3 group had a reduced incidence of acute rejection (0.5 versus 1.0) per recipient and the onset of first episodes was delayed (mean onset: 13 versus 35 days after transplantation). One year actuarial primary graft survival was 88% in the prophylactic OKT3 group as compared with only 50% in the initial group. The outcome in the positive AGXM group was similar to a concurrent group (n = 32) with a negative AGXM and immediate graft function. On the other hand, the subset of positive AGXM regraft recipients treated with prophylactic OKT3 fared poorly, with a 36% (4/11) incidence of primary nonfunction. In summary, a positive AGXM, as defined in this report, is not a contraindication to primary renal transplantation--in fact, the use of the AGXM will identify recipients that would benefit from prophylactic OKT3.