A systematic review of experimental methods to manipulate secondary hyperalgesia in humans: protocol

Background Neuropathic pain affects 7–10% of people, but responds poorly to pharmacotherapy, indicating a need for better treatments. Mechanistic research on neuropathic pain frequently uses human surrogate models of the secondary hyperalgesia that is a common feature of neuropathic pain. Experimentally induced secondary hyperalgesia has been manipulated with pharmacological and non-pharmacological methods to clarify the relative contributions of different mechanisms to secondary hyperalgesia. However, this literature has not been systematically synthesised. The aim of this systematic review is to identify, describe, and compare methods that have been used to manipulate experimentally induced secondary hyperalgesia in healthy humans. Methods A systematic search strategy will be supplemented by reference list checks and direct contact with identified laboratories to maximise the identification of data reporting the experimental manipulation of experimentally induced secondary hyperalgesia in healthy humans. Duplicated screening, risk of bias assessment, and data extraction procedures will be used. Authors will be asked to provide data as necessary. Data will be pooled and meta-analyses conducted where possible, with subgrouping according to manipulation method. Manipulation methods will be ranked for potency and risk. Discussion The results of this review will provide a useful reference for researchers interested in using experimental methods to manipulate secondary hyperalgesia in humans and will help to clarify the relative contributions of different mechanisms to secondary hyperalgesia

DNA origami-based single-molecule forcespectroscopy elucidates RNA Polymerase IIIpre-initiation complex stability

The TATA-binding protein (TBP) and a transcription factor (TF) IIB-like factor are important constituents of all eukaryotic initiation complexes. The reason for the emergence and strict requirement of the additional initiation factor Bdp1 in the RNA polymerase (RNAP) III system, however, remained elusive. A poorly studied aspect in this context is the effect of DNA strain arising from DNA compaction and transcriptional activity on initiation complex formation. We made use of a DNA origami-based force clamp to follow the assembly of human initiation complexes in the RNAP II and RNAP III systems at the single-molecule level under piconewton forces. We demonstrate that TBP-DNA complexes are force-sensitive and TFIIB is sufficient to stabilise TBP on a strained promoter. In contrast, Bdp1 is the pivotal component that ensures stable anchoring of initiation factors, and thus the polymerase itself, in the RNAP III system. Thereby, we offer an explanation for the crucial role of Bdp1 for the high transcriptional output of RNAP III

Is word-level lexical stress sensitivity affected by downregulation to the left superior temporal gyrus using TMS?

This paper reports two experiments using Transcranial Magnetic Stimulation (TMS) to investigate whether word-level lexical stress involves the left superior temporal gyrus (STG) using a grammar classification task designed to elicit a typicality effect. Experiment 1 used text presented stimuli and, although was not able to elicit a typicality effect, found response times were significantly slower in the no TMS condition compared to when the, control, right PAR region was downregulated. In Experiment 2, speech was presented instead of text and accuracy and response times were similar across all three conditions. A lexical decision control task found evidence, from response time analysis, that the left STG and the right PAR were involved in word and nonword judgments. The discussion explores the findings relative to lexical stress and the role of cortical regions in word and response processing

Differential role for phosphorylation in alternative polyadenylation function versus nuclear import of SR-like protein CPSF6

Cleavage factor I mammalian (CFIm) complex, composed of cleavage and polyadenylation specificity factor 5 (CPSF5) and serine/arginine-like protein CPSF6, regulates alternative polyadenylation (APA). Loss of CFIm function results in proximal polyadenylation site usage, shortening mRNA 3' untranslated regions (UTRs). Although CPSF6 plays additional roles in human disease, its nuclear translocation mechanism remains unresolved. Two β-karyopherins, transportin (TNPO) 1 and TNPO3, can bind CPSF6 in vitro, and we demonstrate here that while the TNPO1 binding site is dispensable for CPSF6 nuclear import, the arginine/serine (RS)-like domain (RSLD) that mediates TNPO3 binding is critical. The crystal structure of the RSLD-TNPO3 complex revealed potential CPSF6 interaction residues, which were confirmed to mediate TNPO3 binding and CPSF6 nuclear import. Both binding and nuclear import were independent of RSLD phosphorylation, though a hyperphosphorylated mimetic mutant failed to bind TNPO3 and mislocalized to the cell cytoplasm. Although hypophosphorylated CPSF6 largely supported normal polyadenylation site usage, a significant number of mRNAs harbored unnaturally extended 3' UTRs, similar to what is observed when other APA regulators, such as CFIIm component proteins, are depleted. Our results clarify the mechanism of CPSF6 nuclear import and highlight differential roles for RSLD phosphorylation in nuclear translocation versus regulation of APA

Barriers to Quality Perioperative Care Delivery in Low- and Middle-Income Countries: A Qualitative Rapid Appraisal Study.

BACKGROUND: Provision of timely, safe, and affordable surgical care is an essential component of any high-quality health system. Increasingly, it is recognized that poor quality of care in the perioperative period (before, during, and after surgery) may contribute to significant excess mortality and morbidity. Therefore, improving access to surgical procedures alone will not address the disparities in surgical outcomes globally until the quality of perioperative care is addressed. We aimed to identify key barriers to quality perioperative care delivery for 3 "Bellwether" procedures (cesarean delivery, emergency laparotomy, and long-bone fracture fixation) in 5 low- and middle-income countries (LMICs). METHODS: Ten hospitals representing secondary and tertiary facilities from 5 LMICs were purposefully selected: 2 upper-middle income (Colombia and South Africa); 2 lower-middle income (Sri Lanka and Tanzania); and 1 lower income (Uganda). We used a rapid appraisal design (pathway mapping, ethnography, and interviews) to map out and explore the complexities of the perioperative pathway and care delivery for the Bellwether procedures. The framework approach was used for data analysis, with triangulation across different data sources to identify barriers in the country and pattern matching to identify common barriers across the 5 LMICs. RESULTS: We developed 25 pathway maps, undertook >30 periods of observation, and held >40 interviews with patients and clinical staff. Although the extent and impact of the barriers varied across the LMIC settings, 4 key common barriers to safe and effective perioperative care were identified: (1) the fragmented nature of the care pathways, (2) the limited human and structural resources available for the provision of care, (3) the direct and indirect costs of care for patients (even in health systems for which care is ostensibly free of charge), and (4) patients' low expectations of care. CONCLUSIONS: We identified key barriers to effective perioperative care in LMICs. Addressing these barriers is important if LMIC health systems are to provide safe, timely, and affordable provision of the Bellwether procedures

Induced intraocular light scatter and the sensitivity gradient of the normal visual field

The influence of intraocular light scatter on the perimetric sensitivity profile of the normal eye was investigated using a series of light-scattering cells containing 0.01%, 0.02% and 0.025% concentrations of 500 nm diameter latex beads. The degree of induced intraocular light scatter was quantified by measuring contrast sensitivity using the Nicolet CS2000 system in the presence and absence of both wide- and narrow-angle glare light. Perimetric sensitivity out to an eccentricity of 30 degrees was assessed, using the Octopus 201 and the Dicon AP3000 automated perimeters, with the three light-scatter cells and in the cell-free control condition. The results for both functions were expressed as the difference between the control response and that recorded under the particular experimental condition. Perimetric attenuation increased with increase in intraocular light scatter; the extent of the attenuation varied with stimulus type, bowl luminance and eccentricity