Biological variability of cell-free DNA in healthy females at rest within a short time course

International Journal of Legal Medicine - Alterations in cell-free DNA concentration (cfDNA) over time have been studied in diseased or injured patients or analyzed in athletes during exhaustive...     

Prevalence of cortical superficial siderosis in patients with cognitive impairment

Cortical superficial siderosis (cSS) is a magnetic resonance imaging marker of cerebral amyloid angiopathy (CAA) and can be its sole imaging sign. cSS has further been identified as a risk marker for future intracranial hemorrhage. Although uncommon in the general population, cSS may be much more prevalent in high risk populations for amyloid pathology. We aimed to determine the frequency of cSS in patients with cognitive impairment presenting to a memory clinic. We prospectively evaluated consecutive patients presenting to our memory clinic between April 2011 and April 2013. Subjects received neuropsychological testing using the Consortium to Establish a Registry for Alzheimer’s Disease battery (CERAD-NP). Two hundred and twelve patients with documented cognitive impairment further underwent a standardized 3T-MR-imaging protocol with T2*-weighted gradient-echo sequences for detection of cSS. Thirteen of 212 patients (6.1 %) displayed cSS. In seven of them (54 %) cSS was the only imaging sign of CAA. Patients with cSS did not differ from patients without cSS with regard to medical history, age or cardiovascular risk profile. Subjects with cSS performed worse in the mini-mental state examination (p = 0.001), showed more white matter hyperintensities (p = 0.005) and more often had microbleeds (p = 0.001) compared to those without cSS. cSS is common in patients with cognitive impairment. It is associated with lower cognitive scores, white matter hyperintensities and microbleeds and can be the only imaging sign for CAA in this patient group.     

Gut inflammation and expression of ICC in a fetal lamb model of fetoscopic intervention for gastroschisis

Background

The pathogenesis of intestinal dysmotility in gastroschisis is not completely understood. Peel formation and disorganization of interstitial Cajal cells (ICC) have been proposed in humans. The aim of this study was to evaluate the impact of prenatal coverage of gastroschisis on gut inflammation and expression of ICC in a fetal lamb model.

Methods

Twenty-one German blackhead sheep with an abdominal wall defect that was created fetoscopically on day 77 of 145 days gestation were used in this study. Intrauterine surgery with the aim to cover the defect was performed 3 weeks later; two fetuses were covered completely, 5 partially and 11 remained uncovered. Three fetuses without gastroschisis were used as controls. All fetuses were retrieved by cesarean section at day 135. Samples of the small intestine were stained with hematoxylin and eosin for histologic analysis of peel formation and serosal and muscular thickness. For ICC detection, immunohistochemistry using anti-CD117 (c-Kit) antibody was used.

Results

In all samples with exposure to amniotic fluid, peel formation and significantly decreased ICC were found. Complete coverage reduced peel formation and disorganization of ICC compared to uncovered animals almost to the level of controls.

Conclusions

Peel formation and ICC derangement were significantly reduced by prenatal coverage of gastroschisis. Moreover, this animal model mimics the histopathological bowel changes as seen in human gastroschisis and may, therefore, be used for further research on the pathophysiology and fetal therapy of this malformation.     

The irre Cell Recognition Module (IRM) Protein Kirre Is Required to Form the Reciprocal Synaptic Network of L4 Neurons in the Drosophila Lamina

Each neuropil module, or cartridge, in the fly's lamina has a fixed complement of cells. Of five types of monopolar cell interneurons, only L4 has collaterals that invade neighboring cartridges. In the proximal lamina, these collaterals form reciprocal synapses with both the L2 of their own cartridge and the L4 collateral branches from two other neighboring cartridges. During synaptogenesis, L4 collaterals strongly express the cell adhesion protein Kirre, a member of the irre cell recognition module (IRM) group of proteins (, J Neurogenet, 23, 48–67). The authors show by mutant analysis and gene knockdown techniques that L4 neurons develop their lamina collaterals in the absence of this cell adhesion protein. Using electron microscopy (EM), the authors demonstrate, however, that without Kirre protein these L4 collaterals selectively form fewer synapses. The collaterals of L4 neurons of various genotypes reconstructed from serial-section EM revealed that the number of postsynaptic sites was dramatically reduced in the absence of Kirre, almost eliminating any synaptic input to L4 neurons. A significant reduction of presynaptic sites was also detected in kirre⁰ mutants and gene knockdown flies using RNA interference. L4 neuron reciprocal synapses are thus almost eliminated. A presynaptic marker, Brp-short^GFP confirmed these data using confocal microscopy. This study reveals that removing Kirre protein specifically disrupts the functional L4 synaptic network in the Drosophila lamina.     

Directed transport of bacteria-based drug delivery vehicles: bacterial chemotaxis dominates particle shape

Several attenuated and non-pathogenic bacterial species have been demonstrated to actively target diseased sites and successfully deliver plasmid DNA, proteins and other therapeutic agents into mammalian cells. These disease-targeting bacteria can be employed for targeted delivery of therapeutic and imaging cargos in the form of a bio-hybrid system. The bio-hybrid drug delivery system constructed here is comprised of motile Escherichia coli MG1655 bacteria and elliptical disk-shaped polymeric microparticles. The transport direction for these vehicles can be controlled through biased random walk of the attached bacteria in presence of chemoattractant gradients in a process known as chemotaxis. In this work, we utilize a diffusion-based microfluidic platform to establish steady linear concentration gradients of a chemoattractant and investigate the roles of chemotaxis and geometry in transport of bio-hybrid drug delivery vehicles. Our experimental results demonstrate for the first time that bacterial chemotactic response dominates the effect of body shape in extravascular transport; thus, the non-spherical system could be more favorable for drug delivery applications owing to the known benefits of using non-spherical particles for vascular transport (e.g. relatively long circulation time).     

Six-month results following treatment of aggressive periodontitis with antimicrobial photodynamic therapy or amoxicillin and metronidazole

Objective

The use of antibacterial photodynamic therapy (aPDT) additionally to scaling and root planing (SRP) has been shown to positively influence the clinical outcomes. However, at present, it is unknown to what extent aPDT may represent a potential alternative to the use of systemic antibiotics in nonsurgical periodontal therapy in patients with aggressive periodontitis (AP). The aim of this study was to evaluate the outcomes following nonsurgical periodontal therapy and additional use of either aPDT or amoxicillin and metronidazole (AB) in patients with AP.

Material and methods

Thirty-six patients with AP displaying at least three sites with pocket depth (PD) ≥6 mm were treated with SRP and either systemic administration of AB for 7 days or with two episodes of aPDT. The following clinical parameters were evaluated at baseline and at 6 months: plaque index (PI), bleeding on probing (BOP), PD, gingival recession (GR) and clinical attachment level (CAL).

Results

Thirty-five patients have completed the 6-month evaluation. At 6 months, mean PD was statistically significantly reduced in both groups (from 5.0?±?0.8 to 3.0?±?0.6 mm with AB and from 5.1?±?0.5 to 3.9?±?0.8 mm with aPDT (p?p?p?p?=?0.03). Both therapies resulted in statistically significant reductions in all parameters compared to baseline.

Conclusion

While both treatments resulted in statistically significant clinical improvements, AB showed statistically significantly higher PD reduction and lower number of pockets ≥7 mm compared to aPDT.

Clinical relevance

In patients with AP, the two times application of aPDT in conjunction with nonsurgical periodontal therapy cannot be considered an alternative to the systemic use of amoxicillin and metronidazole.     

Transforming growth factor-β-mediated autocrine growth regulation of gliomas as detected with phosphorothioate antisense oligonucleotides

Transforming growth factors-β1 and -β2 (TGF-β1 and -β2) are important growth-regulatory proteins for astroglial neoplasms. We analyzed their role in tumor-cell proliferation in 12 glioma cell lines, employing phosphorothioate antisense oligodeoxynucleotides (S-ODNs, 14 mer), specifically targeted against the coding sequences of TGF-β1-mRNA and TGF-β2-mRNA. TGF-β1-S-ODNs inhibited cell proliferation in 5 of 12 gliomas, whereas TGF-β2-S-ODNs reduced the cell proliferation in all glioma cell lines, compared to nonsense-S-ODN-treated and S-ODN-untreated cells as controls. The efficacy and specificity of antisense effects was validated by Northern-blot analysis and determination of protein concentrations in culture supernatants (ELISA). Exogenous hrTGF-β1 either stimulated or inhibited the cell lines, whereas pnTGF-β2 stimulated the proliferation of most glioma cells. Blocking the extracellular pathway of TGF-β by neutralizing antibodies only slightly inhibited those cell lines, which were markedly stimulated by TGF-βs. As the effects of TGF-β2-S-ODNs were much stronger than those of TGF-β neutralizing antibodies, we postulate that the endogenously produced TGF-β2 control glioma-cell proliferation, in part by an intracellular loop. © 1996 Wiley-Liss, Inc.     

Vapour-liquid equilibria and segment-molar excess gibbs free energies of concentrated poly(butyl methacrylate) solutions

Solvent activities were measured by an isopiestic sorption technique for solutions of poly(butyl methacrylate) and poly(tert-butyl methacrylate), respectively, in various solvents between 323 K and 373 K (or 403 K). The experimental data were reduced to segment-molar excess Gibbs free energies and to χ-functions. There is a clear difference in the thermodynamic behaviour of both polymers in their corresponding solutions due to the steric effect of the tert-butyl group. The chain-of-rotators equation-of-state model was used to calculate the thermodynamic quantities applying a group-contribution approach. In general, good agreement can be observed between experimental and calculated results.