Long lasting complex nocturnal hallucinations during Osmotic Release Oral System (OROS) methylphenidate treatment in a 7-year old girl

We report a case of a girl with Attention deficit hyperactivity disorder (ADHD) and Oppositional defiant disorder (ODD) who experienced a 3-hour episode of nocturnal complex bizarre visual hallucinations when treated with 18 mg Osmotic Release Oral System (OROS) methylphenidate (MPH). Nocturnal polysomnography performed two weeks later revealed REM sleep reduction (17%) and fragmentation . Two episodes of confusional arousals were recorded. This finding is typical of parasomnia associated with NREM sleep - disorder of arousal. We hypothesize that this preexisting sleep impairment represents a factor of vulnerability to MPH sleep side effects. In our search of literature, we found no report of nocturnal hallucination alone during treatment with stimulants.     

Cancer physics: diagnostics based on damped cellular elastoelectrical vibrations in microtubules

This paper describes a proposed biophysical mechanism of a novel diagnostic method for cancer detection developed recently by Vedruccio. The diagnostic method is based on frequency selective absorption of electromagnetic waves by malignant tumors. Cancer is connected with mitochondrial malfunction (the Warburg effect) suggesting disrupted physical mechanisms. In addition to decreased energy conversion and nonutilized energy efflux, mitochondrial malfunction is accompanied by other negative effects in the cell. Diminished proton space charge layer and the static electric field around the outer membrane result in a lowered ordering level of cellular water and increased damping of microtubule-based cellular elastoelectrical vibration states. These changes manifest themselves in a dip in the amplitude of the signal with the fundamental frequency of the nonlinear microwave oscillator—the core of the diagnostic device—when coupled to the investigated cancerous tissue via the near-field. The dip is not present in the case of healthy tissue.     

Key regulators of mitochondrial biogenesis are increased in kidneys of growth hormone receptor knockout (GHRKO) mice

The growth hormone receptor knockout (GHRKO) mice are remarkably long-lived and highly insulin sensitive. Alterations in mitochondrial biogenesis are associated with aging and various metabolic derangements. We have previously demonstrated increased gene expression of key regulators of mitochondriogenesis in kidneys, hearts and skeletal muscles of GHRKO mice. The aim of the present study was to quantify the protein levels of the following regulators of mitochondriogenesis: peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), AMP-activated protein kinase α (AMPKα), phospho-AMPKα (p-AMPKα), sirtuin-3 (SIRT-3), endothelial nitric oxide synthase (eNOS), phospho-eNOS (p-eNOS), nuclear respiratory factor-1 (NRF-1) and mitofusin-2 (MFN-2) in skeletal muscles and kidneys of GHRKOs in comparison to normal mice. We also were interested in the effects of calorie restriction (CR) and visceral fat removal (VFR) on these parameters. Both CR and VFR improve insulin sensitivity and can extend life span. Results: The renal levels of PGC-1α, AMPKα, p-AMPKα, SIRT-3, eNOS, p-eNOS and MFN-2 were increased in GHRKOs. In the GHRKO skeletal muscles, only MFN-2 was increased. Levels of the examined proteins were not affected by CR (except for PGC-1α and p-eNOS in skeletal muscles) or VFR. Conclusion: GHRKO mice have increased renal protein levels of key regulators of mitochondriogenesis, and this may contribute to increased longevity of these knockouts.     

The Presence and Localization of Melatonin Receptors in the Rat Aorta

Melatonin is involved in blood pressure modulation in rats and humans. Some of the effects of melatonin are presumably mediated via two G-protein-coupled receptors (MT₁ and MT₂), but the distribution of MT₁ and MT₂ in the cardiovascular system remains to be explored comprehensively. We investigated the expression of both the receptors in the rat aorta on mRNA level by RT-PCR and real time RT-PCR as well as on protein level via western blotting and immunofluorescence microscopy. We verified MT₁ mRNA expression in the rat aorta and demonstrated the absence of MT₂ mRNA in this vessel type. MT₁ receptors were confirmed also at the protein level, and surprisingly they were preferentially localized to the tunica adventitia. Since no daily changes in MT₁ mRNA expression were detected, we suppose that the circadian changes in circulating melatonin concentrations are sufficient to mediate circadian effects of melatonin in the aorta. The localization of MT₁ in the tunica adventitia suggests an influence of melatonin on vasa vasorum function and signal transduction in the aorta wall.     

Is there a typical germinal center? A large-scale immunohistological study on the cellular composition of germinal centers during the hapten-carrier-driven primary immune response in mice

Germinal centers (GCs) are complex, multicell-type, transient structures that form in secondary lymphatic tissues in response to T cell-dependent stimulation. This process is crucial to the adaptive immune response because it is the source of affinity maturation and long-lived B cell memory. Our previous studies showed that the growth of murine splenic GCs is nonsynchronized, involving broad-volume distributions of individual GCs at any time. This raises the question whether such a thing as a typical GC exists. To address this matter, we acquired large-scale confocal data on GCs throughout the course of the 2-phenyl-5-oxazolone chicken serum albumin-driven primary immune response in BALB/c mice. Semiautomated image analysis of 3457 GC sections revealed that, although there is no typical GC in terms of size, GCs have a typical cellular composition in that the cell ratios of resident T cells, macrophages, proliferating cells, and apoptotic nuclei are maintained during the established phase of the response. Moreover, our data provide evidence that the dark zone (DZ) and light zone (LZ) compartments of GCs are about the same size and led us to estimate that the minimal cell loss rate in GCs is 3% per hour. Furthermore, we found that the population of GC macrophages is larger and more heterogeneous than previously thought, and that despite enrichment of T cells in the LZ, the DZ of murine splenic GCs is not poor in T cells. DZ and LZ differ in the T cell-to-macrophage ratio rather than in the density of T cells.     

High-frequency electric field and radiation characteristics of cellular microtubule network

Microtubules are important structures in the cytoskeleton, which organizes the cell. Since microtubules are electrically polar, certain microtubule normal vibration modes efficiently generate oscillating electric field. This oscillating field may be important for the intracellular organization and intercellular interaction. There are experiments which indicate electrodynamic activity of variety of cells in the frequency region from kHz to GHz, expecting the microtubules to be the source of this activity. In this paper, results from the calculation of intensity of electric field and of radiated electromagnetic power from the whole cellular microtubule network are presented. The subunits of microtubule (tubulin heterodimers) are approximated by elementary electric dipoles. Mechanical oscillation of microtubule is represented by the spatial function which modulates the dipole moment of subunits. The field around oscillating microtubules is calculated as a vector superposition of contributions from all modulated elementary electric dipoles which comprise the cellular microtubule network. The electromagnetic radiation and field characteristics of the whole cellular microtubule network have not been theoretically analyzed before. For the perspective experimental studies, the results indicate that macroscopic detection system (antenna) is not suitable for measurement of cellular electrodynamic activity in the radiofrequency region since the radiation rate from single cells is very low (lower than 10?2? W). Low noise nanoscopic detection methods with high spatial resolution which enable measurement in the cell vicinity are desirable in order to measure cellular electrodynamic activity reliably.     

Binding of two PriA-PriB complexes to the primosome assembly site initiates primosome formation

A direct quantitative analysis of the initial steps in primosome assembly, involving PriA and PriB proteins and the minimal primosome assembly site (PAS) of phage ?X174, has been performed using fluorescence intensity, fluorescence anisotropy titration, and fluorescence resonance energy transfer techniques. We show that two PriA molecules bind to the PAS at both strong and weak binding sites on the DNA, respectively, without detectable cooperative interactions. Binding of the PriB dimer to the PriA-PAS complex dramatically increases PriA's affinity for the strong site, but only slightly affects its affinity for the weak site. Associations with the strong and weak sites are driven by apparent entropy changes, with binding to the strong site accompanied by a large unfavorable enthalpy change. The PriA-PriB complex, formed independently of the DNA, is able to directly recognize the PAS without the preceding the binding of PriA to the PAS. Thus, the high-affinity state of PriA for PAS is generated through PriA-PriB interactions. The effect of PriB is specific for PriA-PAS association, but not for PriA-double-stranded DNA or PriA-single-stranded DNA interactions. Only complexes containing two PriA molecules can generate a profound change in the PAS structure in the presence of ATP. The obtained results provide a quantitative framework for the elucidation of further steps in primosome assembly and for quantitative analyses of other molecular machines of cellular metabolism.     

XRCC4 protein interactions with XRCC4-like factor (XLF) create an extended grooved scaffold for DNA ligation and double strand break repair

The XRCC4-like factor (XLF)-XRCC4 complex is essential for nonhomologous end joining, the major repair pathway for DNA double strand breaks in human cells. Yet, how XLF binds XRCC4 and impacts nonhomologous end joining functions has been enigmatic. Here, we report the XLF-XRCC4 complex crystal structure in combination with biophysical and mutational analyses to define the XLF-XRCC4 interactions. Crystal and solution structures plus mutations characterize alternating XRCC4 and XLF head domain interfaces forming parallel super-helical filaments. XLF Leu-115 ("Leu-lock") inserts into a hydrophobic pocket formed by XRCC4 Met-59, Met-61, Lys-65, Lys-99, Phe-106, and Leu-108 in synergy with pseudo-symmetric β-zipper hydrogen bonds to drive specificity. XLF C terminus and DNA enhance parallel filament formation. Super-helical XLF-XRCC4 filaments form a positively charged channel to bind DNA and align ends for efficient ligation. Collective results reveal how human XLF and XRCC4 interact to bind DNA, suggest consequences of patient mutations, and support a unified molecular mechanism for XLF-XRCC4 stimulation of DNA ligation.