Frequency‐specific disruptions of neuronal oscillations reveal aberrant auditory processing in schizophrenia

Individuals with schizophrenia exhibit abnormalities in evoked brain responses in oddball paradigms. These could result from (a) insufficient salience‐related cortical signaling (P300), (b) insufficient suppression of irrelevant aspects of the auditory environment, or (c) excessive neural noise. We tested whether disruption of ongoing auditory steady‐state responses at predetermined frequencies informed which of these issues contribute to auditory stimulus relevance processing abnormalities in schizophrenia. Magnetoencephalography data were collected for 15 schizophrenia and 15 healthy subjects during an auditory oddball paradigm (25% targets; 1‐s interstimulus interval). Auditory stimuli (pure tones: 1 kHz standards, 2 kHz targets) were administered during four continuous background (auditory steady‐state) stimulation conditions: (1) no stimulation, (2) 24 Hz, (3) 40 Hz, and (4) 88 Hz. The modulation of the auditory steady‐state response (aSSR) and the evoked responses to the transient stimuli were quantified and compared across groups. In comparison to healthy participants, the schizophrenia group showed greater disruption of the ongoing aSSR by targets regardless of steady‐state frequency, and reduced amplitude of both M100 and M300 event‐related field components. During the no‐stimulation condition, schizophrenia patients showed accentuation of left hemisphere 40 Hz response to both standard and target stimuli, indicating an effort to enhance local stimulus processing. Together, these findings suggest abnormalities in auditory stimulus relevance processing in schizophrenia patients stem from insufficient amplification of salient stimuli.     

Sleep Loss and Affective Functioning: More Than Just Mood

Empirical evidence supports an intimate link between sleep and affective functioning. While the bidirectional relationship between sleep duration and mood is well documented, limited research targets other aspects of affective functioning, such as emotion and emotion regulation, or considers their interrelationships. The present review summarizes research examining the relationship between sleep and emotion, emotion regulation, and mood, and presents a theoretical model representing the relationships between these constructs. Disruptions to sleep and mood may trigger and maintain a negative cascade, leading to more entrenched sleep problems and psychopathology. Given that insufficient sleep is a widespread phenomenon, understanding the interrelationships between sleep and affective functioning has implications for both public health and clinical practice.     

Propagation of viruses infecting waterfowl on continuous cell lines of Muscovy duck (Cairina moschata) origin

Duck circovirus, duck hepatitis A virus 1, goose parvovirus and goose haemorrhagic polyomavirus are economically damaging pathogens of waterfowl, and replicate poorly or not at all in established cell lines. AGE1.CR, AGE1.CR.pIX and AGE1.CS cell lines, originating from the Muscovy duck, were tested for their suitability to isolate and identify these viruses. Immunofluorescence (IF) and quantitative polymerase chain reaction investigations verified that all cell lines are permissive for all four viruses; however, AGE1.CR.pIX proved to be the most productive and most sensitive for viral infection. IF experiments revealed that the time of one infectious cycle is approximately 12 to 14 h in the AGE1.CR.pIX cells in the case of the three DNA viruses, while it is 10 to 12 h for DHAV-1. Specific viral infectivity and the limit of detection by IF varied between 55 and 1484 copies, depending on the viruses and cell lines. Despite the high sensitivity of the cell lines for viruses, their viral productivity remained relatively low for the investigated field isolates. However, optimization of virus infection and/or the adaptation of the viruses to the cells can raise viral productivity and can make these cell lines suitable for vaccine development and production.     

The mutagenic footprint of low-fidelity Pol I ColE1 plasmid replication in E. coli reveals an extensive interplay between Pol I and Pol III

ColE1 plasmid replication is unidirectional and requires two DNA polymerases: DNA polymerase I (Pol I) and DNA polymerase III (Pol III). Pol I initiates leading-strand synthesis by extending an RNA primer, allowing the Pol III holoenzyme to assemble and finish replication of both strands. The goal of the present work is to study the interplay between Pol I and Pol III during ColE1 plasmid replication, to gain new insights into Pol I function in vivo. Our approach consists of using mutations generated by a low-fidelity mutant of Pol I (LF-Pol I) during replication of a ColE1 plasmid as a footprint for Pol I replication. This approach allowed mapping areas of Pol I replication on the plasmid with high resolution. In addition, we were able to approximate the strandedness of Pol I mutations throughout the plasmid, allowing us to estimate the spectrum of the LF-Pol I in vivo. Our study produced the following three mechanistic insights: (1) we identified the likely location of the polymerase switch at ~200 bp downstream of replication initiation; (2) we found evidence suggesting that Pol I can replicate both strands, supporting earlier studies indicating a functional redundancy between Pol I and Pol III (3) we found evidence pointing to a specific role of Pol I during termination of lagging-strand replication. In addition, we illustrate how our strand-specific footprinting approach can be used to dissect factors modulating Pol I fidelity in vivo.     

Extracorporeal shock-wave lithotripsy of gallstones: Boston experience with the Dornier MPL 9000 lithotripter

After the success of shock-wave therapy for fragmentation of renal stones, machines for shock-wave therapy of gallbladder stones were quick to follow. In Munich, gallstones were successfully treated in 174 of 175 patients who were also taking ursodiol to help solubilize the calculous rubble left after treatment. In Boston, of the initial 87 patients accepted, 58 were treated for a single stone (mean diameter 15.7 mm), 16 were treated for 2 stones, and 13 for 3 stones. Although reporting of exact results is not possible before the Food and Drug Administration issues a clearance, it is fair to say that both patients and physicians are generally pleased with the results.     

Superficial Vascularity of Temporomandibular Joint Retrodiskal Tissue: An Element of the Internal Derangement Process

Superficial vascular changes in the retrodiskal tissue are an aspect of the remodeling process during progressive anterior displacement of the temporomandibular joint (TMJ) disk. The salient portion of the remodeled retrodiskal tissue (RRT) is contained in a 3 x 3 grid of arthroscopic fields in the superior joint space, plus the tympanic portion of the remodeled retrodiskal tissue. A four-level vascularity classification system gives a statistically significant association between superficial avascularity of the remodeled retrodiskal tissue and progressive stages of disk derangement. In particular, simultaneous avascularity in both the tympanic remodeled retrodiskal tissue and the central arthroscopic field occurs with severe disk displacement without reduction. Analyses are based on 16 microscopic studies, 25 magnetic resonance imaging and tomographic imaging studies, and 26 arthroscopic studies.