Novel features in the genetic code and codon reading patterns in Neurospora crassa mitochondria based on sequences of six mitochondrial tRNAs

We report the sequences of Neurospora crassa mitochondrial alanine, leucine₁, leucine₂, threonine, tryptophan, and valine tRNAs. On the basis of the anticodon sequences of these tRNAs and of a glutamine tRNA, whose sequence analysis is nearly complete, we infer the following: (i) The N. crassa mitochondrial tRNA species for alanine, leucine₂, threonine, and valine, amino acids that belong to four-codon families (GCN, CUN, ACN, and GUN, respectively; N = U, C, A, or G) all contain an unmodified U in the first position of the anticodon. In contrast, tRNA species for glutamine, leucine₁, and tryptophan, amino acids that use codons ending in purines (CA_G^A, UU_G^A, and UG_G^A, respectively) contain a modified U derivative in the same position. These findings and the fact that we have not detected any other isoacceptor tRNAs for these amino acids suggest that N. crassa mitochondrial tRNAs containing U in the first position of the anticodon are capable of reading all four codons of a four-codon family whereas those containing a modified U are restricted to reading codons ending in A or G. Such an expanded codon-reading ability of certain mitochondrial tRNAs will explain how the mitochondrial protein-synthesizing system operates with a much lower number of tRNA species than do systems present in prokaryotes or in eukaryotic cytoplasm. (ii) The anticodon sequence of the N. crassa mitochondrial tryptophan tRNA is U^*CA and not CCA or CmCA as is the case with tryptophan tRNAs from prokaryotes or from eukaryotic cytoplasm. Because a tRNA with U^*CA in the anti-codon would be expected to read the codon UGA, as well as the normal tryptophan codon UGG, this suggests that in N. crassa mitochondria, as in yeast and in human mitochondria, UGA is a codon for tryptophan and not a signal for chain termination. (iii) The anticodon sequences of the two leucine tRNAs indicate that N. crassa mitochondria use both families of leucine codons (UU_A^G and CUN; N = U, C, A, or G) for leucine, in contrast to yeast mitochondria [Li, M. & Tzagoloff, A. (1979) Cell 18, 47-53] in which the CUA leucine codon and possibly the entire CUN family of leucine codons may be translated as threonine.     

Effects of writing down the request for help: A randomized controlled trial

Background: Studies investigating interventions, aimed at improving patient satisfaction by exploring the patient's request for help, show conflicting results.

Objectives: To investigate whether writing down the request for help on a request card, prior to the consultation improves patient satisfaction.

Methods: This study was a single-blind randomized controlled trial, in which the patients were blinded to the intervention. Patients were recruited in two rural practices (five GPs) and one urban practice (four GPs) in The Netherlands. Consecutive patients with a new request for help were asked to participate. All patients received general information about patient satisfaction. After randomization, patients in the intervention group were asked to fill in a card with their request(s) for help; the general practitioners started the consultations with these questions. We used the ‘Professional Care’ subscale of the Consultation Satisfaction Questionnaire (CSQ) to examine the effect of the intervention on patient satisfaction. Secondary outcomes were patient satisfaction measured with the patient's VAS score, the GP's VAS score on satisfaction, consultation time, the other subscales of the CSQ, and the number of consultations during follow-up.

Results: There was no difference in patient satisfaction (CSQ, VAS) between both groups. We also did not find any differences between the other subscales of the CSQ.

Conclusion: A beneficial effect of the use of a ‘request card’ by the patient on patient satisfaction of the consultation could not be demonstrated.     

Binding-Induced Fluorescence of Serotonin Transporter Ligands: A Spectroscopic and Structural Study of 4-(4-(Dimethylamino)phenyl)-1-methylpyridinium (APP+) and APP+ Analogues

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Die heilsame Szene – Methodenübergreifende Therapie mit Psychodrama und Katathym Imaginativer Psychotherapie (KIP) – Ein Fallbeispiel

Katathym Imaginative Psychotherapy (KIP)/Guided Affective Imagery (GAI) as well as psychodrama use an imaginary space in which fantasy and creativity are stimulated, regression is allowed in the service of the self and experiential and cathartic processes are all used therapeutically. On the other hand at different levels, scene and action along with contact, physical movement and kinesthetic experience, become real (Berger-Becker and Grothaus-Neiss 2012). In KIP this happens in an imaginative manner, in psychodrama it works by real action, by which spatial dimension and conflict are more clearly delineated. The case vignette described here of a psychodynamic long term therapy in which KIP as well as psychodrama were used, exemplifies the suitability of the combined application of both methods.     

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...     

Results of posterior cranial vault remodeling for plagiocephaly and brachycephaly by the meander technique

Objective

Several techniques to remodel the posterior calvarium in order to increase intracranial volume (ICV) and to improve cosmetic appearance are reported. This study presents the results of meander technique in patients with brachycephaly and posterior plagiocephaly.

Methods

During December 2011 and July 2013, a total of 12 children (median age: 15 months) underwent posterior cranial vault remodeling by the meander technique (brachycephaly, n?=?6; posterior plagiocephaly, n?=?6). The available pre- and postoperative MRIs were assessed with regard to ICV, cranial index (CI) and asymmetry index (AI) as well as the position of the cerebellar tonsils.

Results

No intra- or postoperative complications were observed. Blood transfusions were necessary in nine of 12 patients. A significant increase of the ICV from 1,178.4?±?134.5 to 1,293.0?±?137.5 cm³ (p?p?p?p?p?p?Conclusion The presented surgical technique is considered to be safe. The technique is capable to significantly increase ICV and improve cosmetic appearance of the remodeled calvarium. Further evidence that posterior cranial vault remodeling influences the position of the cerebellar tonsils is added by the results of the study.     

Rasch analysis of clinical outcome measures in spinal muscular atrophy

Introduction: Trial design for SMA depends on meaningful rating scales to assess outcomes. In this study Rasch methodology was applied to 9 motor scales in spinal muscular atrophy (SMA). Methods: Data from all 3 SMA types were provided by research groups for 9 commonly used scales. Rasch methodology assessed the ordering of response option thresholds, tests of fit, spread of item locations, residual correlations, and person separation index. Results: Each scale had good reliability. However, several issues impacting scale validity were identified, including the extent that items defined clinically meaningful constructs and how well each scale measured performance across the SMA spectrum. Conclusions: The sensitivity and potential utility of each SMA scale as outcome measures for trials could be improved by establishing clear definitions of what is measured, reconsidering items that misfit and items whose response categories have reversed thresholds, and adding new items at the extremes of scale ranges. Muscle Nerve 49 :422–430, 2014     

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.