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Introduction: Litigation in healthcare is a large financial burden to the NHS and can be a cause of great stress to clinicians. The overall number of claims across specialities, from the years 1995-2017 have increased. Despite being one of the smaller surgical specialities, litigation costs are still significant within Otolaryngology. In this piece we sought to analyse the available data to identify trends within litigation and therefore which areas of practise could be improved.Methods: A freedom of information request was submitted to NHS Resolution for summarised data on claims coded under 'Otolaryngology' or 'ENT' between 1996 and 2017. Information was collected on the total number of claims, the number of successful claims and details on the reasons for making claims.Results: The total number of claims made against Otolaryngology departments from 1996/97 to 2016/17 was 1952. The overall number of claims have increased during this time period. The total amount of money paid out between 1996 and 2017 was £108, 240, 323. The top causes of claim by injury were unnecessary pain and unnecessary operations. The highest number of claims by cause were for failure or delay in diagnosis and intraoperative problems.Conclusion: These results highlight areas that local units can focus on to reduce their litigation burden. Targeted initiatives aimed at improving patient-clinician communication, the consent process and improving local organisational efficiency will address a significant proportion of claims. Re-examination of this data on a regular basis can serve as a useful adjunct in assessing the impact of quality improvement initiatives and implementation of best practiseswithin the speciality. [ABSTRACT FROM AUTHOR]

It is estimated only 8–11% of patients with glioblastoma (GBM) enrol in clinical trials, limiting treatment development. We analysed the clinical and demographic features of patients with GBM enroled in clinical trials at the University of Texas MD Anderson Cancer Center (MDACC). We reviewed the records of adult patients treated for primary GBM between 2007 and 2012 at the MDACC. A total of 755 patients were identified: 133 were deemed non-eligible, 111 were deemed trial eligible but received standard care and 511 participated in a clinical trial (311 for newly diagnosed glioblastoma [nGBM] and 200 for recurrent glioblastoma [rGBM]). Population characteristics were analysed using descriptive statistics, and survival end-points were evaluated with the Kaplan–Meier method. The median age of clinical trial participants and trial eligible patients was 53.2 years (standard deviation 12.1). Most patients (49.4%) were enroled in a clinical trial protocol for nGBM. The majority of nGBM trial participants were male patients (65.1%), white (86.3%), married (84.4%) and in state (59.9%). Employment status, education, symptoms, tumour location, performance status, extent of resection and treatment facility differed between nGBM trial participants and non-participants. Patients who were eligible but did not enrol tended to be older, have worse performance status and live farther away from the MDACC. Numerous disease and demographic barriers exist in trial enrolment in patients with GBM. This study highlights some of these obstacles, which require attention to improve patient enrolment to clinical trials. Patient and physician engagement in novel therapeutic strategies is essential to improving outcomes in this disease. • A small minority of patients with glioblastoma enrol in therapeutic clinical trials. • Demographic, disease and treatment-related variables influence trial enrolment. • Older age and poor functional status are associated with not enroling in trials. • Patients living farther from the treating centre were less likely to enrol. [ABSTRACT FROM AUTHOR]

Background and Aims Endoscopic resection (ER) is safe and effective for Barrett's esophagus (BE) containing high-grade dysplasia (HGD) or mucosal adenocarcinoma (T1A). The risk of metachronous neoplasia is reduced by ablation of residual BE by using radiofrequency ablation (RFA) or argon plasma coagulation (APC). These have not been compared directly. We aimed to recruit up to 100 patients with BE and HGD or T1A confirmed by ER over 1 year in 6 centers in a randomized pilot study. Methods Randomization was 1:1 to RFA or APC (4 treatments allowed at 2-month intervals). Recruitment, retention, dysplasia clearance, clearance of benign BE, adverse events, healthcare costs, and quality of life by using EQ-5D, EORTC QLQ-C30, or OES18 were assessed up to the end of the trial at 12 months. Results Of 171 patients screened, 76 were randomized to RFA (n = 36) or APC (n = 40). The mean age was 69.7 years, and 82% were male. BE was <5 cm (n = 27), 5 to 10 cm (n = 45), and >10 cm (n = 4). Sixty-five patients completed the trial. At 12 months, dysplasia clearance was RFA 79.4% and APC 83.8% (odds ratio [OR] 0.7; 95% confidence interval [CI], 0.2-2.6); BE clearance was RFA 55.8%, and APC 48.3% (OR 1.4; 95% CI, 0.5-3.6). A total of 6.1% (RFA) and 13.3% (APC) had buried BE glands. Adverse events (including stricture rate after starting RFA 3/36 [8.3%] and APC 3/37 [8.1%]) and quality of life scores were similar, but RFA cost $27491 more per case than APC. Conclusion This pilot study suggests similar efficacy and safety but a cost difference favoring APC. A fully powered non-inferiority trial is appropriate to confirm these findings. (Clinical trial registration number: NCT01733719.) [ABSTRACT FROM AUTHOR]

Background & Aims Barrett's esophagus (BE) increases the risk of esophageal adenocarcinoma (EAC). We found the risk to be BE has been associated with single nucleotide polymorphisms (SNPs) on chromosome 6p21 (within the HLA region) and on 16q23, where the closest protein-coding gene is FOXF1 . Subsequently, the Barrett's and Esophageal Adenocarcinoma Consortium (BEACON) identified risk loci for BE and esophageal adenocarcinoma near CRTC1 and BARX1 , and within 100 kb of FOXP1 . We aimed to identify further SNPs that increased BE risk and to validate previously reported associations. Methods We performed a genome-wide association study (GWAS) to identify variants associated with BE and further analyzed promising variants identified by BEACON by genotyping 10,158 patients with BE and 21,062 controls. Results We identified 2 SNPs not previously associated with BE: rs3072 (2p24.1; odds ratio [OR] = 1.14; 95% CI: 1.09–1.18; P = 1.8 × 10 −11 ) and rs2701108 (12q24.21; OR = 0.90; 95% CI: 0.86–0.93; P = 7.5 × 10 −9 ). The closest protein-coding genes were respectively GDF7 (rs3072), which encodes a ligand in the bone morphogenetic protein pathway, and TBX5 (rs2701108), which encodes a transcription factor that regulates esophageal and cardiac development. Our data also supported in BE cases 3 risk SNPs identified by BEACON (rs2687201, rs11789015, and rs10423674). Meta-analysis of all data identified another SNP associated with BE and esophageal adenocarcinoma: rs3784262, within ALDH1A2 (OR = 0.90; 95% CI: 0.87–0.93; P = 3.72 × 10 −9 ). Conclusions We identified 2 loci associated with risk of BE and provided data to support a further locus. The genes we found to be associated with risk for BE encode transcription factors involved in thoracic, diaphragmatic, and esophageal development or proteins involved in the inflammatory response. [ABSTRACT FROM AUTHOR]

Background & Aims: The existence of slowly cycling, adult stem cells has been challenged by the identification of actively cycling cells. We investigated the existence of uncommitted, slowly cycling cells by tracking 5-iodo-2''-deoxyuridine (IdU) label-retaining cells (LRCs) in normal esophagus, Barrett''s esophagus (BE), esophageal dysplasia, adenocarcinoma, and healthy stomach tissues from patients. Methods: Four patients (3 undergoing esophagectomy, 1 undergoing esophageal endoscopic mucosal resection for dysplasia and an esophagectomy for esophageal adenocarcinoma) received intravenous infusion of IdU (200 mg/m2 body surface area; maximum dose, 400 mg) over a 30-minute period; the IdU had a circulation half-life of 8 hours. Tissues were collected at 7, 11, 29, and 67 days after infusion, from regions of healthy esophagus, BE, dysplasia, adenocarcinoma, and healthy stomach; they were analyzed by in situ hybridization, flow cytometry, and immunohistochemical analyses. Results: No LRCs were found in dysplasias or adenocarcinomas, but there were significant numbers of LRCs in the base of glands from BE tissue, in the papillae of the basal layer of the esophageal squamous epithelium, and in the neck/isthmus region of healthy stomach. These cells cycled slowly because IdU was retained for at least 67 days and co-labeling with Ki-67 was infrequent. In glands from BE tissues, most cells did not express defensin-5, Muc-2, or chromogranin A, indicating that they were not lineage committed. Some cells labeled for endocrine markers and IdU at 67 days; these cells represented a small population (<0.1%) of epithelial cells at this time point. The epithelial turnover time of the healthy esophageal mucosa was approximately 11 days (twice that of the intestine). Conclusions: LRCs of human esophagus and stomach have many features of stem cells (long lived, slow cycling, uncommitted, and multipotent), and can be found in a recognized stem cell niche. Further analyses of these cells, in healthy and metaplastic epithelia, is required. [Copyright &y& Elsevier]

Background & Aims: Esophageal adenocarcinoma (EA) is increasingly common among patients with Barrett''s esophagus (BE). We aimed to provide consensus recommendations based on the medical literature that clinicians could use to manage patients with BE and low-grade dysplasia, high-grade dysplasia (HGD), or early-stage EA. Methods: We performed an international, multidisciplinary, systematic, evidence-based review of different management strategies for patients with BE and dysplasia or early-stage EA. We used a Delphi process to develop consensus statements. The results of literature searches were screened using a unique, interactive, Web-based data-sifting platform; we used 11,904 papers to inform the choice of statements selected. An a priori threshold of 80% agreement was used to establish consensus for each statement. Results: Eighty-one of the 91 statements achieved consensus despite generally low quality of evidence, including 8 clinical statements: (1) specimens from endoscopic resection are better than biopsies for staging lesions, (2) it is important to carefully map the size of the dysplastic areas, (3) patients that receive ablative or surgical therapy require endoscopic follow-up, (4) high-resolution endoscopy is necessary for accurate diagnosis, (5) endoscopic therapy for HGD is preferred to surveillance, (6) endoscopic therapy for HGD is preferred to surgery, (7) the combination of endoscopic resection and radiofrequency ablation is the most effective therapy, and (8) after endoscopic removal of lesions from patients with HGD, all areas of BE should be ablated. Conclusions: We developed a data-sifting platform and used the Delphi process to create evidence-based consensus statements for the management of patients with BE and early-stage EA. This approach identified important clinical features of the diseases and areas for future studies. [Copyright &y& Elsevier]

Objective Clinical experience suggests that dachshunds are prone to bradycardia during general anaesthesia (GA). The study investigated mean heart rates in anaesthetized dachshunds and other breeds of dog. Study Design Retrospective clinical study. Animals Sixty one dachshunds and 62 dogs of other breeds met inclusion criteria. Methods Clinical records of small breed dogs undergoing GA for spinal Magnetic Resonance Imaging between September 2008 and March 2010 were identified and examined. Data collected included drugs administered, baseline heart (HR) and respiratory (fR) rates and rectal temperature. The following information was noted from anaesthetic records: HR, fR, mean non-invasive arterial pressure and end-tidal carbon dioxide (P e′CO2) and anaesthetic agent (F e′agent) during the first 60 minutes of anaesthesia; rectal temperature at a time closest to the cessation of anaesthesia, ventilatory mode (spontaneous/mechanical) and fluid infusion rate. Univariate analysis with Student t-test and Fisher's test identified parameters significant in predicting a lowered HR. A multivariate analysis investigated their effect on the mean HR during GA. Results No differences were found between groups regarding: age, baseline HR, baseline temperature, incidence of hypotension, F e′agent, mean P e′CO2 and fluid infusion rate. Body mass was smaller for dachshunds (6.7 ± 1.5 kg) compared to other breeds (7.8 ± 1.8 kg) ( p = 0.0005). The lowest HR recorded was lower in dachshunds (64 ± 19 beats minute−1) compared to other breeds (72 ± 21 beats minute−1) ( p = 0.03). Mean HR was lower in dachshunds (75 ± 21 beats minute−1) compared to other breeds (84 ± 21 beats minute−1) ( p = 0.02). Post-procedural temperature (°C) was lower in dachshunds (35.5 ± 1.1) compared to other breeds (36.1 ± 1.2) ( p = 0.007) and anticholinergics were also administered more frequently ( p = 0.026). Multivariate analysis identified that breed and mean P e′CO2 affected mean HR during anaesthesia. Conclusion This study supported our hypothesis that dachshunds have a lower mean HR under GA than other small breed dogs. [ABSTRACT FROM AUTHOR]

Many regulatory processes in biology involve reversible association of proteins with membranes. Clotting proteins bind to phosphatidylserine (PS) on cell surfaces, but a clear picture of this interaction has yet to emerge. We present a novel explanation for membrane binding by GLA domains of clotting proteins, supported by biochemical studies, solid-state NMR analyses, and molecular dynamics simulations. The model invokes a single "phospho-L-serine-specific" interaction and multiple "phosphate-specific" interactions. In the latter, the phosphates in phospholipids interact with tightly bound Ca2+ in GLA domains. We show that phospholipids with any headgroup other than choline strongly synergize with PS to enhance factor X activation. We propose that phosphatidylcholine and sphin gomyelin (the major external phospholipids of healthy cells) are anticoagulant primarily because their bulky choline headgroups sterically hinder access to their phosphates. Following cell damage or activation, exposed PS and phosphatidylethanolamine collaborate to bind GLA domains by providing phospho-L-ser- me-specific and phosphate-specific interactions, respectively. [ABSTRACT FROM AUTHOR]

Background & Aims: The clonality of colitis-associated neoplasia has not been fully determined. One previous report showed polyclonal origins with subsequent monoclonal outgrowth. We aimed to assess the clonality and mutation burden of individual crypts in colitis-associated neoplasias to try to identify gatekeeping founder mutations, and explore the clonality of synchronous lesions to look for field effects. Methods: Individual crypts (range, 8–21 crypts) were microdissected from across 17 lesions from 10 patients. Individual crypt adenomatous polyposis coli (APC), p53, K-RAS, and 17p loss of heterozygosity mutation burden was established using polymerase chain reaction and sequencing analysis. Serial sections underwent immunostaining for p53, β-catenin, and image cytometry to detect aneuploidy. Results: In most lesions an oncogenic mutation could be identified in all crypts across the lesion showing monoclonality. This founder mutation was a p53 lesion in the majority of neoplasms but 4 tumors had an initiating K-RAS mutation. Some nondysplastic crypts surrounding areas of dysplasia were found to contain clonal p53 mutations and in one case 3 clonal tumors arose from a patch of nondysplastic crypts containing a K-RAS mutation. Conclusions: This study used mutation burden analysis of individual crypts across colitis-associated neoplasms to show lesion monoclonality. This study confirmed p53 mutation as initiating mutation in the majority of lesions, but also identified K-RAS activation as an alternative gatekeeping mutation. Local and segmental field cancerization was found by showing pro-oncogenic mutations in nondysplastic crypts surrounding neoplasms, although field changes are unlikely to involve the entire colon because widely separated tumors were genetically distinct. [Copyright &y& Elsevier]

Background & Aims: How mutations are established and spread through the human stomach is unclear because the clonal structure of gastric mucosal units is unknown. Here we investigate, using mitochondrial DNA (mtDNA) mutations as a marker of clonal expansion, the clonality of the gastric unit and show how mutations expand in normal mucosa and gastric mucosa showing intestinal metaplasia. This has important implications in gastric carcinogenesis. Methods: Mutated units were identified by a histochemical method to detect activity of cytochrome c oxidase. Negative units were laser-capture microdissected, and mutations were identified by polymerase chain reaction sequencing. Differentiated epithelial cells were identified by immunohistochemistry for lineage markers. Results: We show that mtDNA mutations establish themselves in stem cells within normal human gastric body units, and are passed on to all their differentiated progeny, thereby providing evidence for clonal conversion to a new stem cell–derived unit—monoclonal conversion, encompassing all gastric epithelial lineages. The presence of partially mutated units indicates that more than one stem cell is present in each unit. Mutated units can divide by fission to form patches, with each unit sharing an indentical, mutant mtDNA genotype. Furthermore, we show that intestinal metaplastic crypts are clonal, possess multiple stem cells, and that fission is a mechanism by which intestinal metaplasia spreads. Conclusions: These data show that human gastric body units are clonal, contain multiple multipotential stem cells, and provide definitive evidence for how mutations spread within the human stomach, and show how field cancerization develops. [Copyright &y& Elsevier]

Purpose: The impact of oral cancer and its treatment is well documented; therefore, oral rehabilitation (OH; eg, with prosthetics, osseointegrated implants, etc) can be indicated to restore some level of form, function, and well-being. The purpose of this study was to review the current literature and evaluate the impact of OH on quality of life (QoL) after ablative surgery.Materials and Methods: A systematic literature search was conducted using EMBASE, MEDLINE, and PsychINFO. The study population was composed of all articles published from 2000 to 2015. To be included, studies had to use validated, specific head and neck QoL measurements (European Organization for Research and Treatment of Cancer QoL Head and Neck Module or University of Washington QoL Questionnaire). Only 8 articles met these inclusion criteria. In this review, OH was the primary predictor variable and QoL was the primary outcome variable.Results: The 8 articles reviewed used a range of designs, including 1 randomized controlled trial, 3 prospective cohort studies, 3 case series, and 1 single-measurement cross-sectional descriptive study. Sample sizes were small (n = 26 to 102), and there was limited randomization and control of intervention and comparator groups. The overall level of evidence was weak. All studies showed a link between OH and QoL, but the results varied in significance (P < .01 to P = .95).Conclusion: Overall, there appears to be improvement in QoL to varying degrees after OH. However, a more systematic use of QoL measurements is needed before any definitive conclusions can be drawn. [ABSTRACT FROM AUTHOR]

Background & Aims: Studies of the clonal architecture of gastric glands with intestinal metaplasia are important in our understanding of the progression from metaplasia to dysplasia. It is not clear if dysplasias are derived from intestinal metaplasia or how dysplasias expand. We investigated whether cells within a metaplastic gland share a common origin, whether glands clonally expand by fission, and determine if such metaplastic glands are genetically related to the associated dysplasia. We also examined the clonal architecture of entire dysplastic lesions and the genetic changes associated with progression within dysplasia. Methods: Cytochrome c oxidase-deficient (CCO−) metaplastic glands were identified using a dual enzyme histochemical assay. Clonality was assessed by laser capture of multiple cells throughout CCO− glands and polymerase chain reaction sequencing of the entire mitochondrial DNA (mtDNA) genome. Nuclear DNA abnormalities in individual glands were identified by laser capture microdissection polymerase chain reaction sequencing for mutation hot spots and microsatellite loss of heterozygosity analysis. Results: Metaplastic glands were derived from the same clone—all lineages shared a common mtDNA mutation. Mutated glands were found in patches that had developed through gland fission. Metaplastic and dysplastic glands can be genetically related, indicating the clonal origin of dysplasia from metaplasia. Entire dysplastic fields contained a founder mutation from which multiple, distinct subclones developed. Conclusions: There is evidence for a distinct clonal evolution from metaplasia to dysplasia in the human stomach. By field cancerization, a single clone can expand to form an entire dysplastic lesion. Over time, this field appears to become genetically diverse, indicating that gastric cancer can arise from a subclone of the founder mutation. [ABSTRACT FROM AUTHOR]

Abstract: Most steps of the blood clotting cascade require the assembly of a serine protease with its specific regulatory protein on a suitable phospholipid bilayer. Unfortunately, the molecular details of how blood clotting proteins bind to membrane surfaces remain poorly understood, owing to a dearth of techniques for studying protein-membrane interactions at high resolution. Our laboratories are tackling this question using a combination of approaches, including nanoscale membrane bilayers, solid-state NMR, and large-scale molecular dynamics simulations. These studies are now providing structural insights at atomic resolution into clotting protein-membrane interactions. [Copyright &y& Elsevier]

Summary: Syphilitic hepatitis is a rare but well described syndrome, typically manifesting as a mild clinical hepatitis, with complete resolution following therapy. There have been several cases of severe hepatitis, but none progressing to a fatal outcome. We present a case of fulminant hepatitis and hepatic failure in the setting of active secondary syphilis resulting in liver transplantation. The clinical syndrome of syphilitic hepatitis is discussed. This case should highlight and remind physicians of the varied and severe manifestations of syphilis, and prompt physicians to explore syphilis as a possible cause of unexplained hepatitis. [Copyright &y& Elsevier]

Summary: Capnocytophaga ochracea (C. ochracea), a known human microflora, has been reported to cause sepsis in immunocompromised patients and less severe infections such as intrauterine infections, endocarditis, peritonitis and septic arthritis in the immunocompetent patient. We present the first described case of C. ochracea causing severe sepsis and purpura fulminans in an immunocompetent host. [Copyright &y& Elsevier]

Ecosystems on barrier islands provide socio-ecological services to terrestrial and aquatic endangered species, as well as human inhabitants. The management of these coastal ecosystems is challenged by changes in annual and storm time scales driven by atmospheric, oceanographic, geologic, and human processes. Thus, the need for data and methods to accurately quantify and assess ecosystem and land cover evolution to inform stakeholders is on the rise. A dataset of high-resolution color infrared images of a U.S. National Wildlife Refuge is used to quantify annual land cover changes at a barrier island scale and to identify the effects of hurricanes and their recovery periods. Geospatial analysis and change matrices depict the interconnection between 13 land cover classes. Vegetation growth over regions of bare sand formed by storms leads to the creation of successional habitats, while the loss of bare sand dune to beach, and beach to water are indicators of erosional processes. Storms passing along the ocean and sound side of a barrier island result in different land cover changes that can last anywhere from 4 to more than 7 years, respectively. Management practices for coastal regions and the presence of infrastructure partially control the expansion of marshes, bare sand, maritime brush, and dunes. • Geospatial analysis of infrared aerial images of a barrier island depict interconnection between land cover classes. • Storms with different tracks relative to a barrier island result in district land cover changes along the beach and back-barrier regions. • Ocean storms create land cover changes in barrier islands typically lasting less than 5 years. • Bay-side storms create land cover changes in barrier islands lasting more than 7 years. [ABSTRACT FROM AUTHOR]

Mutational studies of T cell receptor (TCR) contact residues on the surface of the human class I major histocompatibility complex (MHC) molecule HLA-A2 have identified a "functional hot spot" that comprises Arg65 and Lys66 and is involved in recognition by most peptide-specific HLA-A2-restricted TCRs. Although there is a significant amount of functional data on the effects of mutations at these positions, there is comparatively little biochemical information that could illuminate their mode of action. Here, we have used a combination of fluorescence anisotropy, functional assays, and Biacore binding experiments to examine the effects of mutations at these positions on the peptide-MHC interaction and TCR recognition. The results indicate that mutations at both position 65 and position 66 influence peptide binding by HLA-A2 to various extents. In particular, mutations at position 66 result in significantly increased peptide dissociation rates. However, these effects are independent of their effects on TCR recognition, and the Arg65-Lys66 region thus represents a true "hot spot" for TCR recognition. We also made the observation that in vitro T cell reactivity does not scale with the half-life of the peptide-MHC complex, as is often assumed. Finally, position 66 is implicated in the "dual recognition" of both peptide and TCR, emphasizing the multiple roles of the class I MHC peptide-binding domain. [ABSTRACT FROM AUTHOR]

Context: Health care professionals (HCPs) currently judge pain presence and intensity in patients with delirium despite the lack of a valid, standardized assessment protocol. However, little is known about how they make these judgments. This information is essential to develop a valid and reliable assessment tool.Objectives: To identify pain cues that HCPs report to judge pain in patients with delirium and to examine whether the pain cues differed based on patient cognitive status and delirium subtype.Methods: Mixed qualitative-quantitative design. Doctors and nurses were recruited. All participants provided written informed consent, and before the recorded interview, demographic information was collected; then participants were asked to describe their practices and beliefs regarding pain assessment and management with older patients who are cognitively intact and patients with delirium. Interviews were transcribed verbatim and coded for pain cues. Coded data were imported into SPSS software (IBM SPSS Statistics Version 24; IBM Corporation, Armonk, NY) to conduct bivariate analyses.Results: The pain cue self-report was stated more often for intact than for delirium patients (χ2 [1; N = 106] = 22.56; P < 0.001). HCPs stated yelling (χ2 [2; N = 159] = 11.14; P = 0.004), when describing pain in hyperactive than in hypoactive and mixed delirium patients; and significantly more HCPs stated grimace (χ2 [2; N = 159] = 6.88; P = 0.03), when describing pain in hypoactive than hyperactive and mixed patients.Conclusion: This study outlines how HCPs conduct pain assessment in patients who are delirious and, also, identifies pain behavior profiles for the subtypes of delirium. [ABSTRACT FROM AUTHOR]

Abstract: Blood clotting reactions, such as those catalyzed by the tissue factor:factor VIIa complex (TF:FVIIa), assemble on membrane surfaces containing anionic phospholipids such as phosphatidylserine (PS). In fact, membrane binding is critical for the function of most of the steps in the blood clotting cascade. In spite of this, our understanding of how the membrane contributes to catalysis, or even how these proteins interact with phospholipids, is incomplete. Making matters more complicated, membranes containing mixtures of PS and neutral phospholipids are known to spontaneously form PS-rich membrane microdomains in the presence of plasma concentrations of calcium ions, and it is likely that blood-clotting proteases such as TF:FVIIa partition into these PS-rich microdomains. Unfortunately, little is known about how membrane microdomain composition influences the activity of blood-clotting proteases, which is typically not under experimental control even in “simple” model membranes. Our laboratories have developed and applied new technologies for studying membrane proteins to gain insights into how blood-clotting protease–cofactor pairs assemble and function on membrane surfaces. This includes using a novel, nanoscale bilayer system (Nanodiscs) that permits assembling blood-clotting protease–cofactor pairs on stable bilayers containing from 65 to 250 phospholipid molecules per leaflet. We have used this system to investigate how local (nanometer-scale) changes in phospholipid bilayer composition modulate TF:FVIIa activity. We have also used detailed molecular-dynamics simulations of nanoscale bilayers to provide atomic-scale predictions of how the membrane-binding domain of factor VIIa interacts with PS in membranes. [Copyright &y& Elsevier]

The 68-residue IA3 polypeptide from Saccharomyces cerevisiae is essentially unstructured, It inhibits its target aspartic proteinase through an unprecedented mechanism whereby residues 2-32 of the polypeptide adopt an amphipathic α-helical conformation upon contact with the active site of the enzyme. This potent inhibitor (Ki < 0.1 nM) appears to be specific for a single target proteinase, saccharopepsin. Mutagenesis of IA3 from S. cerevisiae and its ortholog from Saccharomyces castellii was coupled with quantitation of the interaction for each mutant polypeptide with saccharopepsin and closely related aspartic proteinases from Pichia pastoris and Aspergillus fumigatus. This identified the charged K18/D22 residues on the otherwise hydrophobic face of the amphipathic helix as key selectivity-determining residues within the inhibitor and implicated certain residues within saccharopepsin as being potentially crucial. Mutation of these amino acids established Ala-213 as the dominant specificity-governing feature in the proteinase. The side chain of Ala-213 in conjunction with valine 26 of the inhibitor marshals Tyr-189 of the enzyme precisely into a position in which its side-chain hydroxyl is interconnected via a series of water-mediated contacts to the key K18/D22 residues of the inhibitor. This extensive hydrogen bond network also connects K18/D22 directly to the catalytic Asp-32 and Tyr-75 residues of the enzyme, thus deadlocking the inhibitor in position. In most other aspartic proteinases, the amino acid at position 213 is a larger hydrophobic residue that prohibits this precise juxtaposition of residues and eliminates these enzymes as targets of IA3. The exquisite specificity exhibited by this inhibitor in its interaction with its cognate folding partner proteinase can thus be readily explained. [ABSTRACT FROM AUTHOR]

Abstract: Background and Objectives: Routine statistics and epidemiologic studies often distinguish between types of cardiac death. Our aim was to assess agreement between doctors on cause of death given identical clinical information, and to assess agreement between a physician panel and the original cause of death as coded on national statistics. Methods: Clinical information and autopsy reports on 400 cardiac deaths were randomly selected from a defined population in the West Midlands, UK. A panel of eight clinicians was assembled, and batches of 24–25 cases were sent to pairs of these clinicians who, blinded to the certified cause of death, independently of each other assigned underlying cause of death. Physician panel decision was achieved by consensus. Levels of agreement were assessed using the kappa statistic. Results: Reviewers agreed on cause of death in 54% of cases (kappa = 0.34). Consensus decision of reviewers agreed with death certificate diagnosis in 61.5% (kappa = 0.39). Agreement was higher if an autopsy had been performed (kappa = 0.49). Conclusion: The process of identifying underlying cause of death is of limited reliability, and therefore, limited accuracy. This has implications for design of epidemiologic studies and clinical trials of cardiovascular disease. [Copyright &y& Elsevier]

Anti-N -methyl- d -aspartate receptor (NMDAR) encephalitis is an autoimmune disorder of the central nervous system that commonly manifests as a complex neuropsychiatric syndrome. Antibodies against myelin oligodendrocyte glycoprotein (MOG) are associated with a range of clinical presentations including acute disseminated encephalomyelitis (ADEM), optic neuritis, and transverse myelitis. The concurrence of NMDAR encephalitis and demyelinating syndromes is rare. We describe the case of a 29-year-old male with NMDAR encephalitis and overlapping MOG antibody disease. The aim of this report is to add to the growing knowledge of phenotypic characteristics of overlap syndromes as their clinical and prognostic features may differ from those of single antibody disease. Unlabelled Image [ABSTRACT FROM AUTHOR]