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1.  Enantiomer-selective pharmacokinetics, oral bioavailability, and sex effects of various alpha-lipoic acid dosage forms 
The present study aimed to examine the enantiomer-selective pharmacokinetics (PK), relative bioavailability (Frel), and sex effects of various oral dosage forms of racemic alpha-lipoic acid (ALA). In an open-label, randomized, four-period, four-sequence crossover study, 24 healthy adult subjects (12 males and 12 females) received single doses of 600 mg of ALA in fasted state at four different occasions as follows: three 200 mg tablets (T 200); two 300 mg tablets (T 300); one 600 mg tablet (T 600); and a racemic ALA solution (OS). All tablet formulations (Thioctacid HR) were considered test treatments, while the OS (Thioctacid, 600 T) served as the reference treatment. Serial blood samples were collected over 8 hours postdose to quantify R-(+)- and S-(−)-ALA enantiomer plasma concentrations for the PK evaluation. The maximum observed plasma concentration (Cmax) and total exposure (area under the curve [AUC]0–t) were compared between treatments by analysis of variance. Weight-normalized Cmax and the AUC data of male and female study subjects were applied to examine the presence of sex effects. All treatments displayed rapid absorption of both enantiomers with median time to maximum concentration (tmax) values ranging from 0.33–0.5 hours. The Frel of all tablet formulations was comparable, with R-(+)-enantiomer Cmax test/reference ratios ranging from 36% (T 600) to 43% (T 200), and R-(+)-enantiomer AUC test/reference ratios ranging from 64% (T 600) to 79% (T 300), indicating a favorable Frel of all tablet formulations, especially in terms of the total extent of absorption (AUC). An examination of weight-normalized female/male Cmax and AUC sex ratios for both ALA enantiomers indicated the absence of a significant sex effect for Cmax, as well as 20%–26% and 25%–32% higher R-(+)- and S-(−)-ALA enantiomer AUC outcomes in females when compared to males. The observed modest sex effect was comparable for both ALA enantiomers and across all formulations, and it did not appear to require a dose adjustment in clinical practice.
PMCID: PMC4258503  PMID: 25506250
alpha-lipoic acid; thioctic acid; enantiomers; sex effect; formulation effect; bioavailability
2.  A FIM Study to Assess Safety and Exposure of Inhaled Single Doses of AP301—A Specific ENaC Channel Activator for the Treatment of Acute Lung Injury 
Journal of clinical pharmacology  2014;54(3):341-350.
AP301 is an activator of ENaC-mediated Na+ uptake for the treatment of pulmonary permeability edema in acute respiratory distress syndrome (ARDS). The purpose of this “first-in-man” study was to examine local and systemic safety and systemic exposure of ascending single doses of AP301, when inhaled by healthy male subjects. In a double-blind, placebo-controlled study, 48 healthy male subjects were randomized to 6 ascending dose groups (single doses up to 120 mg) of 8 subjects each (3:1 randomization of AP301: placebo). Serial assessments included spirometry, exhaled nitric oxide (eNO), vital signs, ECG, safety laboratory, adverse events (AE), and blood samples for the quantification of AP301 in plasma. Descriptive statistics was applied. All 48 subjects received treatment, and completed the study as per protocol. No serious, local (e.g., hoarseness, cough, bronchospasm), or dose-limiting AEs were noted. None of the assessments indicated notable dose or time-related alterations of safety outcomes. Observed AP301 systemic exposure levels were very low, with mean Cmax values of <2.5 ng/mL in the highest dose groups. Inhaled AP301 single doses up to 120 mg were safe and well tolerated by healthy male subjects. Distribution of inhaled AP301 was largely confined to the lung, as indicated by very low AP301 systemic exposure levels.
PMCID: PMC4160070  PMID: 24515273
AP301; ENaC activator; first-in-man study; ARDS
3.  Malignant Triton Tumor of the Sciatic Nerve as a Secondary Malignancy after Extended Field Radiotherapy and Chemotherapy of Hodgkin's Disease 
Case Reports in Oncology  2014;7(1):239-245.
Late effects of therapy for Hodgkin's disease include secondary malignancies like leukemia, lymphoma or solid tumors developing after long periods of latency. Ionizing radiation often causes the last group. The highest risks have been described for induced breast and lung cancers. We are the first to report a malignant triton tumor (MTT) as a secondary malignancy after radiotherapy and chemotherapy for Hodgkin's lymphoma. MTT is a very rare subtype of malignant peripheral nerve sheath tumors with rhabdomyoblastic differentiation and an aggressive course of disease.
PMCID: PMC3999579  PMID: 24803902
Triton tumor; Radiotherapy; Second malignancy; Hodgkin's disease
4.  Interaction and Antagonistic Roles of NF-κB and Hes6 in the Regulation of Cortical Neurogenesis 
Molecular and Cellular Biology  2013;33(14):2797-2808.
The involvement of nuclear factor kappa B (NF-κB) in several processes in the postnatal and adult brain, ranging from neuronal survival to synaptogenesis and plasticity, has been documented. In contrast, little is known about the functions of NF-κB during embryonic brain development. It is shown here that NF-κB is selectively activated in neocortical neural progenitor cells in the developing mouse telencephalon. Blockade of NF-κB activity leads to premature cortical neuronal differentiation and depletion of the progenitor cell pool. Conversely, NF-κB activation causes decreased cortical neurogenesis and expansion of the progenitor cell compartment. These effects are antagonized by the proneuronal transcription factor Hes6, which physically and functionally interacts with RelA-containing NF-κB complexes in cortical progenitor cells. In turn, NF-κB exerts an inhibitory effect on the ability of Hes6 to promote cortical neuronal differentiation. These results reveal previously uncharacterized functions and modes of regulation for NF-κB and Hes6 during cortical neurogenesis.
PMCID: PMC3700133  PMID: 23689134
5.  Effect of the PTPN22 and INS Risk Genotypes on the Progression to Clinical Type 1 Diabetes After the Initiation of β-Cell Autoimmunity 
Diabetes  2012;61(4):963-966.
We set out to analyze the role of two major non-HLA gene polymorphisms associated with type 1 diabetes (T1D), PTPN22 1858C/T and insulin gene INS−23 A/T in progression to clinical T1D after the appearance of β-cell autoimmunity. The study population comprised 249 children with HLA-associated T1D susceptibility. All subjects were persistently positive for at least one of the T1D-associated biochemically defined autoantibodies (insulin autoantibody, GAD antibody, or IA-2 antibody), and 136 subjects presented with T1D over a median follow-up of 4.3 years (range 0.0–12.5) after the appearance of the first autoantibody. The PTPN22 1858T allele was strongly associated with progression to T1D after the appearance of the first biochemically defined β-cell autoantibody (hazard ratio 1.68 [95% CI 1.09–2.60], P = 0.02 Cox regression analysis, multivariate test), and the effect remained similar when analyzed after the appearance of the second autoantibody (P = 0.013), whereas INS−23 HphI AA genotype was not associated with progression to clinical diabetes after the appearance of the first or second autoantibody (P = 0.38 and P = 0.88, respectively). The effect of the INS risk genotype seems to be limited to the induction and early phases of β-cell autoimmunity, but the PTPN22 1858T allele instead affects the initiation and late progression phase of diabetes-associated autoimmunity.
PMCID: PMC3314352  PMID: 22357962
6.  Axillary Irradiation as an Imperative Alternative to Axillary Dissection in Clinically Lymph Node-Negative but Sentinel Node-Positive Breast Cancer Patients? 
Breast Care  2011;6(5):353-358.
At the moment, positive sentinel lymph node dissection (SLND) of the axilla is followed by axillary lymph node dissection (ALND) as standard of care. Recent data proves that omitting ALND after positive SLND in clinically lymph node-negative early stage breast cancer patients is feasible with low recurrence rates. The well known effect of radiotherapy to destroy occult tumor cells highly contributes to these results as a large extent of level I and II lymph nodes are unavoidably included in standard tangential radiation treatment fields. Reviewing the up to date published data on axillary lymph node treatment with radiotherapy, we hypothesize that full dosage coverage of level I and II of the axilla in early stage breast cancer will improve outcome and should be further evaluated.
PMCID: PMC3357141  PMID: 22619644
Adjuvant treatment; Breast cancer; Curative radiotherapy; Sentinel lymph node
7.  Effect of HLA Class I and Class II Alleles on Progression From Autoantibody Positivity to Overt Type 1 Diabetes in Children With Risk-Associated Class II Genotypes 
Diabetes  2010;59(12):3253-3256.
Class II alleles define the main HLA effect on type 1 diabetes, but there is an independent effect of certain class I alleles. Class II and class I molecules are differently involved in the initiation and effector phases of the immune response, suggesting that class I alleles would be important determinants in the rate of β-cell destruction. To test this hypothesis we analyzed the role of HLA class I and class II gene polymorphisms in the progression from diabetes-associated autoimmunity to clinical disease.
The effect of HLA-DR-DQ haplotypes and a panel of class I HLA-A and -B alleles on the progression from autoantibody seroconversion to clinical diabetes was studied in 249 children persistently positive for at least one biochemical diabetes-associated autoantibody in addition to islet cell autoantibody.
The progression to clinical disease was separately analyzed after the appearance of the first and the second persistent biochemical autoantibody using Cox regression. Multivariate analysis demonstrated a significant protective effect of the A*03 allele (odds ratio [OR] 0.61, P = 0.042 after the first and OR 0.55, P = 0.027 after the second autoantibody), whereas the B*39 allele had a promoting effect after seroconversion for the second autoantibody (OR 2.4, P = 0.014). When children with the DR3/DR4 genotype were separately analyzed, HLA-B*39 had a strong effect (OR 6.6, P = 0.004 and OR 7.5, P = 0.007, after the appearance of the first and the second autoantibody, respectively). The protective effect of A*03 was seen only among children without the DR3/DR4 combination.
These results confirm that class I alleles affect the progression of diabetes-associated autoimmunity and demonstrate interactions between class I and class II alleles.
PMCID: PMC2992790  PMID: 20739684
8.  From Genetic Risk Awareness to Overt Type 1 Diabetes 
Diabetes Care  2009;32(12):2181-2183.
To evaluate the psychological burden of parents facing increasing risk of type 1 diabetes in their children.
In the population-based Type 1 Diabetes Prediction and Prevention (DIPP) Study, newborn infants with HLA-DQB1–conferred diabetes risk were enrolled in sequential analyses of diabetes-associated autoantibodies. Those persistently positive for at least two autoantibodies were recruited to a randomized double-blinded intervention trial. The experience of stress in parents of 664 children was measured using Parenting Stress Index self-report inventory.
While diagnosis of diabetes increased parental stress, the appearance of autoantibodies or participation in the intervention trial did not. Mothers had higher stress levels than fathers. Single parenthood and chronically ill family members increased parental stress.
Parental stress was not increased by notification of autoantibody positivity or by participation in an intervention trial. Other demanding family conditions contributed to the experience of stress.
PMCID: PMC2782973  PMID: 19752173
9.  Cofactor-Activated Phosphorylation Is Required for Inhibition of Cortical Neuron Differentiation by Groucho/TLE1 
PLoS ONE  2009;4(12):e8107.
Transcriptional co-repressors of the Groucho/transducin-like Enhancer of split (Gro/TLE) family regulate the expression of a variety of genes and are involved in numerous developmental processes in both invertebrate and vertebrate species. More specifically, Gro/TLE1 participates in mechanisms that inhibit/delay the differentiation of cerebral cortex neural progenitor cells into neurons during mammalian forebrain development. The anti-neurogenic function of Gro/TLE1 depends on the formation of protein complexes with specific DNA-binding transcription factors that engage Gro/TLE1 through WRP(W/Y) sequences. Interaction with those transcription partners results in Gro/TLE1 recruitment to selected DNA sites and causes increased Gro/TLE1 phosphorylation. The physiological significance of the latter event, termed “cofactor-activated phosphorylation,” had not been determined. Therefore, this study aimed at clarifying the role of cofactor-activated phosphorylation in the anti-neurogenic function of Gro/TLE1.
Methods and Principal Findings
A combination of site-directed mutagenesis, mass spectrometry, biochemistry, primary cell culture, and immunocytochemical assays was utilized to characterize point mutations of Ser-286, a residue that is phosphorylated in vivo and is located within the serine/proline-rich (SP) domain of Gro/TLE1. Mutation of Ser-286 to alanine or glutamic acid does not perturb the interaction of Gro/TLE1 with DNA-binding partners, including the basic helix-loop-helix transcription factor Hes1, a prototypical anti-neurogenic WRP(W/Y) motif protein. Ser-286 mutations do not prevent the recruitment of Gro/TLE1 to DNA, but they impair cofactor-activated phosphorylation and weaken the interaction of Gro/TLE1 with chromatin. These effects are correlated with an impairment of the anti-neurogenic activity of Gro/TLE1. Similar results were obtained when mutations of Ser-289 and Ser-298, which are also located within the SP domain of Gro/TLE1, were analyzed.
Based on the positive correlation between Gro/TLE1 cofactor-activated phosphorylation and ability to inhibit cortical neuron differentiation, we propose that hyperphosphorylation induced by cofactor binding plays a positive role in the regulation of Gro/TLE1 anti-neurogenic activity.
PMCID: PMC2779591  PMID: 19956621
10.  Toxicity of daily low dose cisplatin in radiochemotherapy for locally advanced head and neck cancer 
To evaluate toxicity of radiochemotherapy schedule using daily-low-dose-cisplatin in radiochemotherapy of locally-advanced head-and-neck-cancer (HNSCC).
Methods and patients
From October 2003 to October 2006, 50 patients with HNSCC (stage III/IVA/IVB) were treated. In 32 patients, surgery and adjuvant radiotherapy(64 Gy), in 18 patients definitive radiotherapy(70 Gy) was performed. Low-dose-cisplatin was applied concomitantly (6 mg/m2/every radiotherapy-day).
Acute toxicity ≥grade 3 was observed in 22 patients (11 patients mucositis/dysphagia, 7 hematologic toxicity, 4 mucositis/dysphagia/hematologic toxicity). 90% of our patients received >80% of the planned cumulative chemotherapy dose, 94% the intended dose of radiotherapy. After median follow-up of 24.2 months, 3-year overall survival and loco-regional control rates were 67.1 and 78%. During follow-up, chronic toxicity ≥grade 3 (xerostomia, subcutaneous fibrosis, or lymphedema) was observed in nine patients.
We found chemoradiation with daily-low-dose-cisplatin to be feasible with advantage of low acute and chronic toxicity. Therefore, use of low-dose-cisplatin should be evaluated in future clinical trials.
PMCID: PMC2687513  PMID: 19107519
Low dose cisplatin; HNSCC; Radiochemotherapy; Toxicity
11.  In vitro studies on the modification of low-dose hyper-radiosensitivity in prostate cancer cells by incubation with genistein and estradiol 
As the majority of prostate cancers (PC) express estrogen receptors, we evaluated the combination of radiation and estrogenic stimulation (estrogen and genistein) on the radiosensitivity of PC cells in vitro.
PC cells LNCaP (androgen-sensitive) and PC-3 (androgen-independent) were evaluated. Estrogen receptor (ER) expression was analyzed by means of immunostaining. Cells were incubated in FCS-free media with genistein 10 μM and estradiol 10 μM 24 h before irradiation and up to 24 h after irradiation. Clonogenic survival, cell cycle changes, and expression of p21 were assessed.
LNCaP expressed both ER-α and ER-β, PC-3 did not. Incubation of LNCaP and PC-3 with genistein resulted in a significant reduction of clonogenic survival. Incubation with estradiol exhibited in low concentrations (0.01 μM) stimulatory effects, while higher concentrations did not influence survival. Both genistein 10 μM and estradiol 10 μM increased low-dose hyper-radiosensitivity [HRS] in LNCaP, while hormonal incubation abolished HRS in PC-3. In LNCaP cells hormonal stimulation inhibited p21 induction after irradiation with 4 Gy. In PC-3 cells, the proportion of cells in G2/M was increased after irradiation with 4 Gy.
We found an increased HRS to low irradiation doses after incubation with estradiol or genistein in ER-α and ER-β positive LNCaP cells. This is of high clinical interest, as this tumor model reflects a locally advanced, androgen dependent PC. In contrast, in ER-α and ER-β negative PC-3 cells we observed an abolishing of the HRS to low irradiation doses by hormonal stimulation. The effects of both tested compounds on survival were ER and p53 independent. Since genistein and estradiol effects in both cell lines were comparable, neither ER- nor p53-expression seemed to play a role in the linked signalling. Nevertheless both compounds targeted the same molecular switch. To identify the underlying molecular mechanisms, further studies are needed.
PMCID: PMC2490684  PMID: 18625043
12.  No supra-additive effects of goserelin and radiotherapy on clonogenic survival of prostate carcinoma cells in vitro 
Oncological results of radiotherapy for locally advanced prostate cancer (PC) are significantly improved by simultaneous application of LHRH analoga (e.g. goserelin). As 85% of PC express LHRH receptors, we investigated the interaction of goserelin incubation with radiotherapy under androgen-deprived conditions in vitro.
LNCaP and PC-3 cells were stained for LHRH receptors. Downstream the LHRH receptor, changes in protein expression of c-fos, phosphorylated p38 and phosphorylated ERK1/2 were analyzed by means of Western blotting after incubation with goserelin and irradiation with 4 Gy. Both cell lines were incubated with different concentrations of goserelin in hormone-free medium. 12 h later cells were irradiated (0 – 4 Gy) and after 12 h goserelin was withdrawn. Endpoints were clonogenic survival and cell viability (12 h, 36 h and 60 h after irradiation).
Both tested cell lines expressed LHRH-receptors. Changes in protein expression demonstrated the functional activity of goserelin in the tested cell lines. Neither in LNCaP nor in PC-3 any significant effects of additional goserelin incubation on clonogenic survival or cell viability for all tested concentrations in comparison to radiation alone were seen.
The clinically observed increase in tumor control after combination of goserelin with radiotherapy in PC cannot be attributed to an increase in radiosensitivity of PC cells by goserelin in vitro.
PMCID: PMC2034383  PMID: 17718927
13.  Methods for Intense Aeration, Growth, Storage, and Replication of Bacterial Strains in Microtiter Plates 
Miniaturized growth systems for heterogeneous culture collections are not only attractive in reducing demands for incubation space and medium but also in making the parallel handling of large numbers of strains more practicable. We report here on the optimization of oxygen transfer rates in deep-well microtiter plates and the development of a replication system allowing the simultaneous and reproducible sampling of 96 frozen glycerol stock cultures while the remaining culture volume remains frozen. Oxygen transfer rates were derived from growth curves of Pseudomonas putida and from rates of oxygen disappearance due to the cobalt-catalyzed oxidation of sulfite. Maximum oxygen transfer rates (38 mmol liter−1 h−1, corresponding to a mass transfer coefficient of 188 h−1) were measured during orbital shaking at 300 rpm at a shaking diameter of 5 cm and a culture volume of 0.5 ml. A shaking diameter of 2.5 cm resulted in threefold-lower values. These high oxygen transfer rates allowed P. putida to reach a cell density of approximately 9 g (dry weight) liter−1 during growth on a glucose mineral medium at culture volumes of up to 1 ml. The growth-and-replication system was evaluated for a culture collection consisting of aerobic strains, mainly from the genera Pseudomonas, Rhodococcus, and Alcaligenes, using mineral media and rich media. Cross-contamination and excessive evaporation during vigorous aeration were adequately prevented by the use of a sandwich cover of spongy silicone and cotton wool on top of the microtiter plates.
PMCID: PMC110593  PMID: 10831450
14.  Pancreatic Drainage Into the Stomach After Pancreatic Resection 
HPB Surgery  1991;5(1):64-65.
PMCID: PMC2442932  PMID: 18612397

Results 1-15 (15)