Telomere length dynamics in normal hematopoiesis and in disease states characterized by increased stem cell turnover.

Telomeres both reflect and limit the replicative lifespan of normal somatic cells. Immature sub-populations of human CD34+38- hematopoietic stem cell (HSC) can be identified in vitro based on their growth kinetics and telomere length. Fluorescence in situ hybridization and flow cytometry (flow-FISH) has been used to characterize telomere length dynamics as a surrogate marker for HSC turnover in vivo. Investigations in normal steady-state hematopoiesis provided the basis for follow-up studies in model scenarios characterized by increased HSC turnover. Disorders with underlying malignant transformation of HSC (e.g., chronic myeloid leukemia (CML)) can be discriminated from disease states with increased HSC turnover rates secondary to depletion of the stem cell compartment, for example, as in defined bone marrow failure syndromes. In some of these model scenarios, the degree of telomere shortening can be correlated with disease duration, disease stage and severity as well as with response to disease-modifying treatment strategies. Whether increased telomere shortening represents a causal link between HSC turnover, replicative senescence and/or the induction of genetic instability in acquired HSC disorders remains to be shown. However, data from congenital disorders, like dyskeratosis congenita (DKC), suggest that disturbed telomere maintenance may play a role for replicative exhaustion of the HSC pool in vivo.     

Expression of Urokinase Plasminogen Activator Receptor on Monocytes from Patients with Relapsing-Remitting Multiple Sclerosis: Effect of Glatiramer Acetate (Copolymer 1)

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system in which peripheral blood monocytes play an important role. We have previously reported that patients with chronic progressive MS (CPMS) have significantly increased numbers of circulating monocytes which express the urokinase plasminogen activator receptor (uPAR). In the present study, we examined the expression of uPAR on monocytes in patients with relapsing-remitting multiple sclerosis (RRMS) not currently participating in a clinical trial and in patients with RRMS who were enrolled in a double-blind multicenter clinical trial designed to examine the effect of glatiramer acetate (copolymer 1; Copaxone) on relapsing disease. Patients with CPMS have sustained high levels of circulating uPAR-positive (uPAR⁺) monocytes. In comparison, patients with RRMS displayed variable levels of circulating uPAR⁺ monocytes. Mean values for uPAR in patients with RRMS were above those seen for controls but were not as high as those observed for patients with secondary progressive MS. Patients with RRMS in the clinical trial also had variable levels of monocyte uPAR. However, patients in the treatment group displayed lower levels following 2 years of treatment. In both placebo-treated and glatiramer acetate-treated patients, the percentage of circulating uPAR⁺ monocytes, as well as the density of uPAR expressed per cell (mean linear fluorescence intensity), increased just prior to the onset of a clinically documented exacerbation. Values fell dramatically with the development of clinical symptoms. uPAR levels in all groups correlated with both clinical activity and severity. Results indicate that monocyte activation is impatient in MS and that glatiramer acetate may have a significant effect on monocyte activation in patients with RRMS.     

Targeting telomerase activity by BIBR1532 as a therapeutic approach in germ cell tumors

Summary Germ cell tumors (GCT) possess a high activity of telomerase, a ribonucleoprotein complex compensating the erosion of telomeres during cell division by adding TTAGGG-repeats to the telomeric ends of chromosomes. Cisplatin, the most important drug in the treatment of GCT, preferentially acts on G-rich regions like telomeres. Inhibiting telomerase in tumors can result in telomere shortening and senescence and could increase the efficacy of chemotherapy in refractory patients. The study evaluated the promise of the small molecule telomerase inhibitor BIBR1532 as single agent and assessed a possible synergism with cisplatin in a preclinical model of GCT. GCT-derived cell line 2102EP was cultured with or without 10 μM of BIBR1532. Cell expansion was quantified in population doublings (PD). Telomere length was analyzed by fluorescence in situ hybridization and flow cytometry (flow-FISH). The sensitivity of the cells towards cisplatin was determined by MTT-assay. Telomerase activity was assessed by TRAP assay. After 300 PD, telomere length diminished from 18.5 kb ± 0.59 kb to 8.9 ± 0.1 kb in BIBR1532 treated 2102 EP cells as compared to 14.5 ± 0.0 kb in untreated control cells. Treated cells did not show altered growth kinetics compared to untreated counterparts. Despite effective shortening of telomeres, the sensitivity of the treated cells towards cisplatin did not increase. Concomitant treatment with BIBR1532 and cisplatin did not result in accelerated telomere shortening. Telomere length can be shortened significantly by telomerase inhibition in GCT cell line models. However, possibly in view of their extensive telomere “reserve,” telomerase inhibition did neither result in increased sensitivity of 2102 EP cells to cisplatin nor did co-treated cells show accelerated telomere shortening. Sandra Mueller, Ulrike Hartmann and Frank Mayer contributed equally to the work. Tim H. Brummendorf and Carsten Bokemeyer contributed equally to the work.     

Serum detection of human urogenital mycoplasma

The authors compared the detection rate of DNA of urogenital Mycoplasmas (Ureaplasma spp. and M. hominis) in the urogenital tract (UGT) and serum samples by polymerase chain reaction. Testing the smears and serum samples from the same patients (n = 112) showed that Ureaplasma was more frequently detected in the UGT smears than in the serum samples. There was the same trend towards M. hominis although the difference was not so significant. Therefore, the detection of these microorganisms in UGT is of more informative value for diagnostic purposes. Examination of the serum samples for these purposes provides useful information in understanding the mechanisms of generalization of Mycoplasma infections and studying the routes and modes of spreading these bacteria in the organism.     

Evaluation of the factors affecting the quality of life and total costs in epilepsy patients on monotherapy with carbamazepine and valproate

OBJECTIVES: To evaluate the effect of different demographic and clinical factors on the quality of life and cost of treatment of epilepsy patients on monotherapy with carbamazepine and valproate. PATIENTS AND METHODS: A total of 146 patients (67 male, 79 female, age range 18-80 years) with focal and generalized seizures were studied for one year. The patients were allocated into two groups depending on the drug they received: group one--46 patients on carbamazepine, and group two--100 patients on valproate. Quality of life (QOL) and total costs per patient per year were calculated. QOL was assessed using a questionnaire--Quality of Life in Epilepsy Inventory (QOLIE-31). Costs included direct medical, non-medical and indirect costs related to either epilepsy or its treatment. The assessed demographic and clinical factors were: age, gender, type of seizures, number of registered adverse events (AE) per three months, interval between seizures and seizure reduction percentage. RESULTS AND CONCLUSIONS: In both groups, age, gender and type of seizures didn't cause significant differences in the formation of QOL and costs. In the carbamazepine patients costs were influenced by the incidence of AEs, the time between seizures and seizure reduction percentage. In the valproate patients costs were mainly influenced by the time period between seizures while QOL by the incidence of AEs.     

Circulating,soluble adhesion proteins in cerebrospinal fluid and serum of patients with multiple sclerosis: Correlation with clinical activity

Soluble adhesion protein intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and endothelial leukocyte adhesion molecule (E-selectin) were measured in serum and cerebrospinal fluid (CSF) of patients with relapsing-remitting multiple sclerosis (RRMS) in remission and in exacerbation, as well as patients with chronic progressive MS, stable MS, and in patients with other neurological and inflammatory diseases (ONDs). Serum ICAM-1 and E-selectin were significantly elevated in patients with MS over those with ONDs and controls. CSF VCAM-1 and E-selectin were found to be elevated over control and disease control samples. No increase in CSF ICAM-1 was observed. Results were analyzed longitudinally and by MS category. In paired CSF and serum samples from patients in exacerbation, elevated VCAM-1 correlated with increased serum VCAM-1 in 5 of 7 patients. Elevated CSF E-selectin did not correlate with elevations in serum E-selectin.     

Properties of Exchange Coupled All-garnet Magneto-Optic Thin Film Multilayer Structures

The effects of exchange coupling on magnetic switching properties of all-garnet multilayer thin film structures are investigated. All-garnet structures are fabricated by sandwiching a magneto-soft material of composition type Bi_1.8Lu_1.2Fe_3.6Al_1.4O₁₂ or Bi₃Fe₅O₁₂:Dy₂O₃ in between two magneto-hard garnet material layers of composition type Bi₂Dy₁Fe₄Ga₁O₁₂ or Bi₂Dy₁Fe₄Ga₁O₁₂:Bi₂O₃. The fabricated RF magnetron sputtered exchange-coupled all-garnet multilayers demonstrate a very attractive combination of magnetic properties, and are of interest for emerging applications in optical sensors and isolators, ultrafast nanophotonics and magneto-plasmonics. An unconventional type of magnetic hysteresis behavior not observed previously in magnetic garnet thin films is reported and discussed.