[Compliance of patients undergoing thromboprophylaxis with enoxaparin: the COMFORT study]

Venous thromboembolism and subsequent pulmonary embolism are frequent and sometimes fatal complications in patients after surgical interventions. To prevent thromboembolisms an effective prophylaxis is necessary and outpatients in particular need adequate compliance. The aim of the prospective non-interventional study COMFORT was to analyze 8,091 outpatients after surgical and orthopedic interventions with different risk profiles with respect to factors affecting patient compliance in a positive or negative way. The follow-up period was 14 days and 92.5 % of the patients took the medication for the prescribed duration, 2.1 % (n = 166) terminated the medication too early and no information was available for 5.9 % (n = 442) of the patients. The reasons given for the premature termination of the injections were no more need for prophylaxis and end of medication by order of the physician due to mobilization or adverse events. Of the patients 73 % stated that the administartion was simple and without any problems and the majority of patients recognized injection as the administration mode of low molecular weight heparin to be the most important medication. The findings of this study can contribute to a better understanding of patient compliance.

Human middle longitudinal fascicle: variations in patterns of anatomical connections

Based on high-resolution diffusion tensor magnetic resonance imaging (DTI) tractographic analyses in 39 healthy adult subjects, we derived patterns of connections and measures of volume and biophysical parameters, such as fractional anisotropy (FA) for the human middle longitudinal fascicle (MdLF). Compared to previous studies, we found that the cortical connections of the MdLF in humans appear to go beyond the superior temporal (STG) and angular (AG) gyri, extending to the temporal pole (TP), superior parietal lobule (SPL), supramarginal gyrus, precuneus and the occipital lobe (including the cuneus and lateral occipital areas). Importantly, the MdLF showed a striking lateralized pattern with predominant connections between the TP, STG and AG on the left and TP, STG and SPL on the right hemisphere. In light of the results of the present study, and of the known functional role of the cortical areas interconnected by the MdLF, we suggested that this fiber pathway might be related to language, high order auditory association, visuospatial and attention functions.

Electron beam annealing of Fe+ implanted Si nanostructures

Silicon nanostructures (nanowhiskers) have been formed at surface densities approximately 10(9) cm-2 by electron beam annealing (EBA) prior to the implantation of 7 keV Fe+ ions to fluences from 1 x 10(13) - 4 x 10(15) Fe+ cm(-2). A second EBA step is then applied to relieve implantation-induced stresses. RBS analysis shows that the implanted Fe remains close to the surface. AFM characterisations of the implanted nanowhiskers before and after the final EBA step are summarised in graphs of height versus surface density. In a striking result it is shown that the nanowhiskers not only survive processing but also grow significantly. For example, at the highest fluence of 4 x 10(15) Fe+ cm(-2), the average height more than doubles: the increases are from 5.0 nm to 6.5 nm under implantation and from 6.5 nm to 11.8 nm under EBA. In addition there is a significant increase in surface density from an initial value of 1.6 x 10(9) cm(-2) to 4.3 x 10(9) cm(-2). These results highlight the feasibility of doping Si surface nanostructures with magnetic ions to fabricate Si devices for spin-dependent enhanced field emission.

Investigation of the osteitis deformans phases in snake vertebrae by double-pulse laser-induced breakdown spectroscopy

Double-pulse laser-induced breakdown spectroscopy (DP-LIBS) was optimized for microspatial analyses of fossil and recent snake vertebrae. As complimentary techniques, solution analysis by inductively coupled plasma mass spectrometry and synchrotron radiation X-ray microtomography was utilized in order to determine the overall concentration of the selected elements in the samples and to visualize nondestructively the fossil sample microstructure, respectively. Elemental mapping of pathological bony tissue by DP-LIBS has been proven as a powerful tool for considering the osteitis deformans phases in fossil vertebrae.

Large area interference lithography using a table-top extreme ultraviolet laser: a systematic study of the degree of mutual coherence

A prototype low cost table-top Ar capillary discharge laser source (1.5 ns pulse duration, lambda = 46.9 nm) was successfully used to produce, by means of interference lithography (with a simple Lloyd mirror setup), large area (0.1 mm(2)) regular patterns from 400 nm down to 22.5 nm (half-pitch) on PMMA/Si (PMMA: polymethylmethacrylate) substrates. The experiments allowed a systematical investigation of the degree of mutual coherence of the source, giving a clear indication that the interference lithography can be pushed down to the ultimate resolution limit of lambda/4.

Conditional associative learning examined in a paralyzed patient with amyotrophic lateral sclerosis using brain-computer interface technology

Background

Brain-computer interface methodology based on self-regulation of slow-cortical potentials (SCPs) of the EEG (electroencephalogram) was used to assess conditional associative learning in one severely paralyzed, late-stage ALS patient. After having been taught arbitrary stimulus relations, he was evaluated for formation of equivalence classes among the trained stimuli.

Methods

A monitor presented visual information in two targets. The method of teaching was matching to sample. Three types of stimuli were presented: signs (A), colored disks (B), and geometrical shapes (C). The sample was one type, and the choice was between two stimuli from another type. The patient used his SCP to steer a cursor to one of the targets. A smiley was presented as a reward when he hit the correct target. The patient was taught A-B and B-C (sample – comparison) matching with three stimuli of each type. Tests for stimulus equivalence involved the untaught B-A, C-B, A-C, and C-A relations. An additional test was discrimination between all three stimuli of one equivalence class presented together versus three unrelated stimuli. The patient also had sessions with identity matching using the same stimuli.

Results

The patient showed high accuracy, close to 100%, on identity matching and could therefore discriminate the stimuli and control the cursor correctly. Acquisition of A-B matching took 11 sessions (of 70 trials each) and had to be broken into simpler units before he could learn it. Acquisition of B-C matching took two sessions. The patient passed all equivalence class tests at 90% or higher.

Conclusion

The patient may have had a deficit in acquisition of the first conditional association of signs and colored disks. In contrast, the patient showed clear evidence that A-B and B-C training had resulted in formation of equivalence classes. The brain-computer interface technology combined with the matching to sample method is a useful way to assess various cognitive abilities of severely paralyzed patients, who are without reliable motor control.

Mapping the intake of different elements in vegetal tissues by dual-energy X-ray imaging at DaPhine synchrotron light source

This article reports on the first utilization of the soft X-ray beamline at the DaPhine synchrotron light source for mapping the intake of different elements in plant tissues. As a test, the method of dual-energy X-ray microradiography was applied to the investigation of the natural sulfur content in dried leaf and root samples. Our ultimate goal was to monitor the pollutant lead and its intake, which was added in controlled doses to the hydroponic medium of laboratory-controlled samples of vegetal species. The results obtained by the nondestructive X-ray radiographic analysis are compared to the values of concentrations determined by a standard chemical analysis utilizing atomic absorption spectroscopy. From this comparison the validity of the X-ray detection of heavy metals in biological samples has been confirmed. The superposition of the dual energy results on the simple planar radiography shows the representation of the pollutant intake directly on the sample structures. It should be pointed out that this method, developed here for plant root and leaves could be applied to any biological sample of interest, but the preparation and observation conditions necessitate different strategies according to the type of sample under analysis.

GJA12 mutations are a rare cause of Pelizaeus-Merzbacher-like disease

BACKGROUND

Pelizaeus-Merzbacher-like disease (PMLD) is a genetically heterogeneous disorder within the group of hypomyelinating leukoencephalopathies. Mutations of the gap junction protein alpha 12 (GJA12) gene are known to cause one autosomal recessive PMLD form. Few patients with GJA12 mutated PMLD have been reported, and to date, the frequency as well as the genotypic and phenotypic spectrum of GJA12 related PMLD is unclear.

METHODS

We report mutation analysis of the GJA12 gene in a clinical and radiologic well-characterized multiethnic cohort of 193 patients with PMLD from 182 families.

RESULTS AND CONCLUSIONS

Only 16 patients (8.3%) from 14 families (7.7%) carry GJA12 mutations including five families where we detected only one mutated allele. Among those, we identified 11 novel alterations. Thus, GJA12 mutations are a rather rare cause for Pelizaeus-Merzbacher-like disease. The clinical phenotype of patients with a GJA12 mutation was evaluated and is overall comparable to the clinical features seen in mild forms of proteolipid protein 1 (PLP1) related disorder but with better cognition and earlier signs of axonal degeneration.

Antifungal usage in children undergoing intensive treatment for acute myeloid leukemia: analysis of the multicenter clinical trial AML-BFM 93

We retrospectively analyzed the antifungal usage in children with acute myeloid leukemia (AML). Overall, 211 of 304 patients (69.4%) received a total of 389 antifungal treatment episodes. In 234 episodes, initial antifungal treatment consisted of amphotericin B [as monotherapy, n = 193; median dosage (range) of amphotericin B deoxycholate 0.6 mg/kg per day (0.02-1.5 mg/kg per day) and of liposomal amphotericin B 3.0 mg/kg per day (0.6-30 mg/kg per day)], in 149 episodes of fluconazole [as monotherapy, n = 143; 5 mg/kg per day (1-29 mg/kg per day)], in 40 of flucytosine [as monotherapy, n = 1; 150 mg/kg per day (40-370 mg/kg per day)], and in 9 of itraconazole [as monotherapy, n = 8; 6 mg/kg per day (1.6-20 mg/kg per day)]. We conclude that the majority of children with AML receives at least one episode of antifungal therapy. Inappropriate dosing and combination of antimycotics need to be addressed in future educational measures.

Growth inhibitory effect of ceramide-incorporated nanoliposomes in human pancreatic cancer cells

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Background: In cancer therapy, it is a challenging task to develop an optimal therapeutic regimen with an improved drug delivery vehicle and a cancer targeting strategy. Liposome-based drug delivery vehicles have been proven feasible and effective in clinical applications. We have recently developed a novel 80 nanometer diameter liposomal formulation that incorporates 30 molar percent C6-ceramide, a lipid-derived second messenger that is proapoptotic to cancer cells, but not to normal cells. Methods: MTT assay was used to evaluate cell proliferation and viability. In vitro soft agar colony forming assay was utilized to assess the transforming activity of pancreatic cancer cell lines. For apoptosis, caspase 3/7 assay was applied. Results: We assessed the biological effect of C6-ceramide nanoliposomes (C6 liposome) in two human pancreatic cancer cell lines, L3.6p1 and Panc1 cells. We demonstrated in L3.6p1 cells as well as Panc1 cells that C6 liposomes, but not control liposomes, increased cytotoxicity, as measured by MTT assay. Moreover, the C6 liposome synergized with low dose gemcitabine, a first line pancreatic cancer neoplastic agent, to dramatically enhance apoptosis, as measured by caspase 3/7 activities. Further, in vitro transforming assays (soft agar colony forming assay) indicated that L3.6p1 cells treated with C6 liposome formed much smaller colonies than that of control cells, suggesting that the C6 liposome alone can inhibit the in vitro transforming ability of the L3.6p1 cells. Conclusions: Collectively, we have developed a novel nanotechnology-based liposomal drug delivery system for pancreatic tumors. Our data suggest that the C6 liposomal formulation is able to enhance the efficacy of gemcitabine to suppress the proliferation and in vitro transforming activity of pancreatic tumor cells. Acknowlegements: Penn State Research Foundation has licensed ceramide liposomes to Tracon Pharmaceutical, Inc. San Diego, CA.

No significant financial relationships to disclose.

Anti-malarial drug targets: screening for inhibitors of 2C-methyl-D-erythritol 4-phosphate synthase (IspC protein) in Mediterranean plants

The recently discovered non-mevalonate pathway of isoprenoid biosynthesis serves as the unique source of terpenoids in numerous pathogenic eubacteria and in apicoplast-type protozoa, most notably Plasmodium, but is absent in mammalian cells. It is therefore an attractive target for anti-infective chemotherapy. The first committed step of the non-mevalonate pathway is catalyzed by 2C-methyl-D-erythritol 4-phosphate synthase (IspC). Using photometric and NMR spectroscopic assays, we screened extracts of Mediterranean plants for inhibitors of the enzyme. Strongest inhibitory activity was found in leaf extracts of Cercis siliquastrum.

Risk of secondary hyperparathyroidism after laparoscopic gastric bypass surgery in obese women

BACKGROUND

Metabolic bone disease is a potential complication of bariatric surgery. The aims of our study were to evaluate the effects of laparoscopic gastric bypass on calcium and vitamin D metabolism, and to identify patients at high risk to develop secondary hyperparathyroidism (HPT).

METHODS

Serum calcium, alkaline phosphatase, intact parathyroid hormone (PTH), and 25-hydroxy (OH) vitamin D were measured at 3, 6, 12, and 24 months after laparoscopic gastric bypass in a cohort of morbidly obese women. Logistic regression was used in both univariate and multivariate models to identify independent preoperative variables associated with secondary HPT.

RESULTS

The study enrolled 193 morbidly obese women. During the 2-year follow-up period, the incidence of elevated PTH levels (>65 pg/ml) was 53.3%. The mean time elapsed between surgery and detection of secondary HPT was 9.1 months (range, 3-24 months). Vitamin D deficiency was observed in 39 patients (20.2%). On univariate analysis, the preoperative factors associated with secondary HPT were race (high PTH levels were detected in 70% of African Americans versus 50% of Caucasians; p < 0.05), preoperative body mass index (BMI; high PTH: 52.5 +/- 10.8 versus normal PTH: 48.9 +/- 7.5 kg/m2; p < 0.01), and age (high PTH: 44.9 +/- 9.2 versus normal PTH: 42.3 +/- 9 years, p < 0.05). Race and age remained independent risk factors for secondary HPT in the multivariate logistic regression model after adjusting for the covariate Roux-limb length. African Americans were at more than 2.5 times greater risk to develop secondary HPT as Caucasian (RR 2.5; 95% CI: 1.03-6.17, p < 0.05). Patients older than 45 years were at 1.8 times higher risk of developing secondary HPT as their younger counterparts (RR 1.8; 95% CI: 1.01-3.32, p < 0.05).

CONCLUSIONS

Morbidly obese women have a high incidence of elevated PTH levels after gastric bypass surgery. Low vitamin D levels did not constitute the only reason behind this finding. African-American women and women older than 45 years of age were at significantly higher risk of developing secondary HPT. In these populations, aggressive supplementation with calcium citrate and vitamin D should be implemented.

Monitoring of the heavy-metal hyperaccumulation in vegetal tissues by X-ray radiography and by femto-second laser induced breakdown spectroscopy

This article reports on the utilization of X-ray microradiography and laser induced breakdown spectroscopy (LIBS) techniques for investigation of the metal accumulation in different part of leaf samples. The potential of the LIBS-analysis for finding the proper plant species for phytoremediation is compared with the results of microradiography measurements at the HERCULES source at ENEA, Rome (Italy) and X-ray microradiography experiments at the ELETTRA Synchrotron, Trieste (Italy).

Damage and ablation of large bandgap dielectrics induced by a 46.9 nm laser beam

We applied a 0.3 mJ, 1.7 ns, 46.9 nm soft-x-ray argon laser to ablate the surface of large bandgap dielectrics: CaF2 and LiF crystals. We studied the ablation versus the fluence of the soft-x-ray beam, varying the fluence in the range 0.05-3 J/cm2. Ablation thresholds of 0.06 and 0.1 J/cm2 and ablation depths of 14 and 20 nm were found for CaF2 and LiF, respectively. These results define new ablation conditions for these large bandgap dielectrics that can be of interest for the fine processing of these materials.