Formation of Artemisinin in Artemisia annua During One Vegetation Period*,1

In order to investigate the possibility of isolating greater amounts of the antimalarial compound artemisinin (quinghaosu), plants of ARTEMISIA ANNUA were cultivated and analysed at different stages of development. We found the highest content just before flowering. It was also possible to correlate development of the plants with the maximum content of artemisinin. ARTEMISIA ANNUA plants cultivated from various other sources were also examine for artemisinin content. According to our results, none of these plants contained sufficient amounts of artemisinin to justify an isolation on a technical scale. Furthermore other Artemisia species were tested. We found artemisinin in only one other species. To possibly increase the amount of artemisinin during the growth period of the plant, we tested two hormone-type growth regulators on A. ANNUA strain 811. The results showed that one of them, chlormequat, was able to increase the artemisinin content by 30% over untreated plants. We also found some slight effects of the growth regulators on morphological criteria of glandular trichomes.     

The use of trimeric isoleucine-zipper fusion proteins to study surface-receptor-ligand interactions in natural killer cells

The ligands for several activating natural killer (NK) cell receptors have not been identified to date. Soluble receptor fusion proteins can be used to stain target cells for the presence of these unidentified ligands. Here, we describe the generation and use of soluble type I NK cell receptor isoleucine-zipper (ILZ) fusion proteins of the immunoglobulin (Ig) superfamily. ILZ-fusion proteins are easy to produce and purify. They form trimeric complexes in solution and display a higher binding avidity than classical immunoglobulin-fusion proteins. ILZ-fusion proteins do not interact with Fc-receptors and can therefore be used to block receptor-ligand interactions in cellular assays. This makes ILZ-fusion proteins a valuable tool to study receptor-ligand interactions in NK cells and other cellular systems.     

Genetic investigations on Silybum marianum and S. eburneum with respect to leaf colour, outcrossing ratio, and flavonolignan composition

In crossing experiments between S. marianum and S. eburneum the number of fruits produced was relatively high as compared to the two parental species. All the F(1)-plants showed the variegated leaf characteristic of S. marianum, whereas after selfing the F(2)-plants had completely green and variegated leaves in a ratio of about 3:1 indicating that the leaf colour is monofactorially inherited. This proves that the two species are only variants. Using leaf colour as the genetic marker, the outcrossing rate in field experiments was studied. Since the outcrossing rate on average is only about 2%, SILYBUM is predominantly a self-pollinator. From 11 randomly selected plants, three inbred generations were produced and their silymarin composition (silibinin, silidianin, silichristin) was studied. Two types of lines could be distinguished based on the relative values of three flavonolignans: lines with approximately 70% silibinin, 30% silichristin, and traces of silidianin in all inbred generations and those with the relative contents of the compounds 30%, 57%, and 13%, respectively.     

Plant regeneration from mesophyll and suspension protoplasts of Silybum marianum

Mesophyll protoplasts of six lines of Silybum marianum were enzymatically isolated from young leaves, embedded in sodium alginate, and cultivated in KM-medium. Division frequencies observed after ten days were strongly influenced by the protoplast density. When 5 x 10 (4)/ml protoplasts were plated, division frequencies of about 35% were obtained, with a protoplast population density of 1 x 10 (5)/ml division frequencies of about 75% resulted. Plant regeneration experiments undertaken with the protocalluses on medium containing BAP led to shoot formation in only two lines with regeneration frequencies of less than 1% in one (M 24) and up to 7% in a second line (M 2), respectively. However, when the protocalluses from line M 2 were treated with thidiazuron (TDZ) in a first culture step, and with BAP in a second step, the shoot formation frequency rose to 22%. Shoots were rooted on hormone free MS agar medium and transferred into soil where plants grew to maturity. Similar results were obtained when protoplasts of the line M 2, isolated from a suspension culture, were cultivated.     

Deletions in chromosome arms 3p and 11q are new prognostic markers in localized and 4s neuroblastoma.

PURPOSE: To find new nonrandom chromosomal changes in neuroblastoma (NB) with a potential to forecast the patient's outcome, alterations in chromosome arms 3p and 11q were investigated. EXPERIMENTAL DESIGN: Frequency and prognostic potential of 3p and 11q alterations in 144 NBs were analyzed using interphase fluorescence in situ hybridization with DNA probes for 3p26 and 11q23. Aberrations were defined as deletion (monosomy of a specific region) or imbalance (at least two intact and additional 3p26- or 11q23-deleted chromosomes). RESULTS: Forty-two of 144 cases (29%) displayed 11q alterations (21% deletions, 8% imbalances). Most aberrations were associated with stage 4 disease (28 of 59, 47%) but were also present in localized and 4s tumors (14 of 85, 16%; P = 0.007). Patients with 11q deletion/imbalance were significantly older at diagnosis (P < 0.001). Changes in 3p were detected in 26 of 144 (18%) samples (15% deletions, 3% imbalances). These alterations were also associated with stage 4 [20 of 59 (34%) versus 6 of 85 (7%) in stages 1-3 and 4s, P = 0.007], and the median age was increased (P < 0.001). Aberrations in both chromosomes were highly associated with each other (P < 0.001). MYCN amplification (MNA) was detected in 10% and 12% of tumors with 11q and 3p alterations, and changes in 1p36 occurred in 13% and 26% of the 3p- and 11q-aberrant tumors. MYCN amplification and 11q deletion/imbalance tended to show an inverse correlation (P = 0.07) as well as 1p and 3p deletion/imbalance (P = 0.07). Patients with 3p and 11q abnormalities in localized/4s tumors showed an inferior outcome compared with those without these alterations (P = 0.002 and P = 0.0027, respectively), in particular in MYCN single copy tumors (P < 0.0001 and P = 0.0006, respectively). CONCLUSION: Alterations in 3p and 11q are frequent nonrandom aberrations in NB and define a new high-risk subgroup in MYCN single copy stage 1-3 and 4s disease.     

A note on calculating asymptotic confidence intervals for the adjusted risk difference and number needed to treat in the Cox regression model

Recently, Laubender and Bender (Stat. Med. 2010; 29: 851–859) applied the average risk difference (RD) approach to estimate adjusted RD and corresponding number needed to treat measures in the Cox proportional hazards model. We calculated standard errors and confidence intervals by using bootstrap techniques. In this paper, we develop asymptotic variance estimates of the adjusted RD measures and corresponding asymptotic confidence intervals within the counting process theory and evaluated them in a simulation study. We illustrate the use of the asymptotic confidence intervals by means of data of the Düsseldorf Obesity Mortality Study. Copyright © 2013 John Wiley & Sons, Ltd.     

Perioperative Therapie des lokal fortgeschrittenen Rektumkarzinoms

The therapeutic approach for locally advanced rectal carcinoma should always comprise multimodality treatment instead of surgical intervention alone. The treatment strategy differs depending on which third of the rectum is affected. During recent years, neoadjuvant treatment concepts have replaced adjuvant chemoradiotherapy for locally advanced rectal cancer. In the current article, we summarize the state of the art in the treatment of locally advanced rectal cancer and discus perspectives of treatment.     

Phospho-CRKL monitoring for the assessment of BCR-ABL activity in imatinib-resistant chronic myeloid leukemia or Ph+ acute lymphoblastic leukemia patients treated with nilotinib

Actual BCR-ABL kinase inhibition in vivo as determined by phospho-CRKL (pCRKL) monitoring has been recognized as a prognostic parameter in patients with chronic myelogenous leukemia treated with imatinib. We report a biomarker sub-study of the international phase I clinical trial of nilotinib (AMN107) using the established pCRKL assay in imatinib-resistant chronic myeloid leukemia or Ph+ acute lymphoblastic leukemia. A minimum dose (200 mg) required for effective BCR-ABL inhibition in imatinib resistant/intolerant leukemia was determined. The pre-clinical activity profile of nilotinib against mutant BCR-ABL was largely confirmed. Substantial differences between peripheral blood baseline pCRKL/CRKL ratios were observed when comparing chronic myeloid leukemia with Ph+ acute lymphoblastic leukemia. Finally, rapid BCR-ABL-reactivation shortly after starting nilotinib treatment was seen in acute lymphoblastic leukemia patients with progressive disease carrying the P-loop mutations Y253H, E255K, or mutation T315I. Monitoring the actual BCR-ABL inhibition in nilotinib treated patients using pCRKL as a surrogate is a means to establish effective dosing and to characterize resistance mechanisms against nilotinib.     

Effect of dose adjustments on the efficacy and safety of tofacitinib in patients with rheumatoid arthritis: a post hoc analysis of an open-label,long-term extension study (ORAL Sequel)

Clinical Rheumatology - We assess the impact of switching versus staying on the same tofacitinib dose on efficacy and safety in patients with rheumatoid arthritis (RA). ORAL Sequel was an...