In silico, in vitro and in vivo analysis of putative virulence factors identified in large clostridial toxin-negative, binary toxin- producing C. difficile strains.

The relevance of large clostridial toxin-negative, binary toxin-producing (A-B-CDT+) Clostridium difficile strains in human infection is still controversial. In this study, we investigated putative virulence traits that may contribute to the role of A-B-CDT+C. difficile strains in idiopathic diarrhea. Phenotypic assays were conducted on 148 strains of C. difficile comprising 10 different A-B-CDT+C. difficile ribotypes (RTs): 033, 238, 239, 288, 585, 586, QX143, QX444, QX521 and QX629. A subset of these isolates (n = 53) was whole-genome sequenced to identify genetic loci associated with virulence and survival. Motility studies showed that with the exception of RT 239 all RTs tested were non-motile. C. difficile RTs 033 and 288 had deletions in the F2 and F3 regions of their flagella operon while the F2 region was absent from strains of RTs 238, 585, 586, QX143, QX444, QX521 and QX629. The flagellin and flagella cap genes, fliC and fliD, respectively, involved in adherence and host colonization, were conserved in all strains, including reference strains. All A-B-CDT+C. difficile strains produced at least three extracellular enzymes (deoxyribonuclease, esterase and mucinase) indicating that these are important extracellular proteins. The toxicity of A-B-CDT+C. difficile strains in Vero cells was confirmed, however, pathogenicity was not demonstrated in a mouse model of disease. Despite successful colonization by most strains, there was no evidence of disease in mice. This study provides the first in-depth analysis of A-B-CDT+C. difficile strains and contributes to the current limited knowledge of these strains as a cause of C. difficile infection.

Readability of endoscopy information leaflets: Implications for informed consent.

INTRODUCTION: Valid consent for gastrointestinal endoscopy is required for ethical and legal reasons. Patients are frequently met by an endoscopist for the first time on the day of their procedure. For valid consent to be possible, the patient needs to have received and understood generic information regarding endoscopy in advance. Patient information leaflets (PILs) need to be easily understood by the majority of the population. METHOD: PILs from 14 secondary care institutions and a sample PIL from the British Society of Gastroenterology were analysed using an online readability tool. Flesch reading ease, Flesch-Kincaid grade (F-K grade) and Simple Measure of Gobbledygook (SMOG) were calculated and compared against national recommendations and literacy standards. RESULT: Average Flesch reading ease score was 57.5, below the threshold of 60 which indicates a document that is easy to read. Average F-K grade and SMOG were 9.7 and 9.4, respectively; both indicating a reading age of 14-15, the recommended reading age being 11-12. There is considerable variation when documents are analysed by institution. Flesch scores varying from 49.7 to 66.1, F-K grade 8.2-11.4 and SMOG 8.3-10.8 (reading ages 13-17). CONCLUSION: All PILs analysed exceeded the recommended reading age for patient information. In the context of "straight to test" endoscopy where patients do not have a consultation with clinicians well versed in endoscopy prior to the day of the procedure, this risks invalidating consent. PILs need to be written carefully to ensure the information provided is accessible to patients, and that the language used is suitably aimed to achieve this.

Negative pressure wound therapy - a review of its uses in orthopaedic trauma.

The use of Negative Pressure Wound Therapy (NPWT) for complex and large wounds has increased in popularity over the past decade. Modern NPWT systems consisting of an open pore foam sponge, adhesive dressing and a vacuum pump producing negative pressure have been used as an adjunct to surgical debridement to treat tissue defects around open fractures and chronic, contaminated wounds. Other uses include supporting skin grafts and protecting wounds at risk of breaking down. This review outlines the current and emerging indications for negative pressure wound therapy in Orthopaedic trauma and the existing preclinical and clinical evidence base for its use.

A novel application for bolus remifentanil: blunting the hemodynamic response to Mayfield skull clamp placement.

OBJECTIVE: Neurosurgery often requires skull immobilization with a Mayfield clamp, which often causes brief intense nociceptive stimulation, hypertension and tachycardia. Blunting this response may help prevent increased intracranial pressure, cerebral aneurysm or vascular malformation rupture, and/or myocardial stress. While various interventions have been described to blunt this response, no reports have compared administration of a propofol versus a remifentanil bolus. METHODS: We retrospectively analyzed the hemodynamic response to Mayfield placement in over 800 patients who received a prior propofol or remifentanil bolus from 2004 to 2010. RESULTS: Patients who received remifentanil experienced a 55% smaller increase in heart rate (p < 0.0001) and a 40% smaller increase in systolic blood pressure (p < 0.0001) after Mayfield placement than patients who received propofol. These data were retrospectively obtained from patients who were not randomized to receive remifentanil versus propofol, and hence these data could be subject to possible confounding. Nonetheless, these differences remained significant after multivariate analysis for possible confounding variables. CONCLUSIONS: Thus, a remifentanil bolus is more effective than a propofol bolus in blunting hemodynamic responses to Mayfield placement, and possibly for other short, intense nociceptive stimuli.

Effect of surgical clipping versus endovascular coiling on recovery from oculomotor nerve palsy in patients with posterior communicating artery aneurysms: A retrospective comparative study and meta-analysis.

BACKGROUND: Oculomotor nerve palsy (OMNP) is a well-recognized complication of posterior communicating artery (PCOM) aneurysms. Only a few comparative studies have assessed the effect of clipping versus coiling on recovery from OMNP in PCOM aneurysms. A retrospective review and meta-analysis was conducted to assess the relationship between PCOM aneurysm treatment and OMNP. MATERIALS AND METHODS: Medical records of all patients presenting between January 2000 and February 2013 with intracranial aneurysm were searched. All patients with OMNP secondary to PCOM aneurysm were included for analysis. Patients undergoing surgical clipping or endovascular coiling were compared with respect to complete resolution of OMNP after aneurysm surgery (i.e., primary outcome). A meta-analysis of published studies of OMNP associated with PCOM aneurysm was performed after a MEDLINE search. RESULTS: Seventeen patients with OMNP secondary to PCOM aneurysms met the inclusion criteria. Surgical clipping (seven of eight patients, or 87.5%) resulted in greater complete resolution of OMNP compared with endovascular coiling (four of nine patients, or 44.4%), P = 0.13. A meta-analysis of similar studies revealed that complete resolution of OMNP was more commonly associated with surgical clipping (36 of 43 patients, or 83.7%) than with endovascular coiling (29 of 55 patients, or 52.7%), yielding an adjusted odds ratio (OR) of 6.04 [confidence interval (CI) =1.88-19.45, P = 0.003]. Multivariate analysis found that the degree of pre-operative OMNP (OR = 0.07, CI = 0.02-0.28, P = 0.001) and surgical clipping (OR = 6.37, CI = 1.73-23.42, P = 0.005) were significant factors that affected the complete recovery of OMNP. CONCLUSION: Complete recovery of OMNP with PCOM aneurysms is more commonly associated with surgical clipping than with endovascular coiling. Also, the degree of pre-operative OMNP and the treatment modality are significant factors that affect the complete recovery of OMNP.

A pilot study of cerebral and haemodynamic physiological changes during sedation with dexmedetomidine or propofol in patients with acute brain injury.

Sedation for the mechanically-ventilated, brain-injured patient remains challenging. The purpose of this pilot study was to compare the cerebral physiologic effects of sedation with propofol versus dexmedetomidine in mechanically-ventilated, brain-injured patients. Using a randomised, crossover, unblinded clinical trial, we enrolled patients with severe brain injury (Glasgow Coma Score ≤8) from traumatic injury, subarachnoid haemorrhage or intracerebral haemorrhage undergoing multimodal monitoring (intracranial pressure, brain temperature, oximetry and microdialysis). Patients received an infusion of either propofol or dexmedetomidine for six hours and then a crossover for the subsequent six hours after sufficient washout/in. Clinical and physiological measurements were recorded hourly. In eight patients, (four traumatic injury, three subarachnoid haemorrhage and one intracerebral haemorrhage), the mean dose of propofol used was 25.5 µg/kg/minute while the mean dose of dexmedetomidine was 0.54 µg/kg/hour. All subjects were effectively sedated to a goal of Richmond Agitation Sedation Scale -2 and Bispectral Index of 50-70 throughout the study period. We did not observe any statistically significant differences between the groups in systemic or cerebral physiologic metrics. Though differences were noted in cerebral metabolic substrates (lactate/pyruvate ratio), none were statistically significant. In our pilot cohort, dexmedetomidine and propofol appear equally effective in sedating severely brain-injured patients and neither is associated with adverse physiological effects as measured by multimodal monitoring. Larger long-term studies are required to determine whether clinically favourable benefits demonstrated in the medical critical care setting also apply to this patient population.

The effect of centralisation on the outcomes of oesophagogastric surgery--a fifteen year audit.

INTRODUCTION: Centralisation of oesophagogastric (OG) resectional services has been proposed to improve patient outcomes in terms of perioperative mortality and long-term survival. Centralisation of services occurred in Gloucester 5 years ago. The aim of this paper is to assess if local patient outcomes have benefited from centralisation. METHODS: All oesophagogastric resections performed in our unit over a 15-year period (10-years pre-centralisation and 5-years post-centralisation) were assessed retrospectively. Patient demographics, pathological details and date of death were identified. Perioperative mortality (30 and 90 day) and estimated Kaplan-Meier survival was compared for cases performed pre- and post-centralisation of services. RESULTS: 456 resections for cancer were performed in the 15-year period; 234 of these were performed pre-centralisation (mean 23.4, range 13-31) and 222 were performed post-centralisation (mean 44.4, range 40-50). Median survival rates for gastric cancer were 1.1 years pre-centralisation and 1.5 years post-centralisation (p = 0.147) and median survival for oesophageal cancer improved from 1.1 years to 2.1 respectively (p = 0.028). Combined OG 30-day mortality rates improved from 10.3% pre-centralisation to 3.6% post-centralisation (p = 0.006, Fisher's exact test). DISCUSSION: Centralisation of OG services in Gloucester has resulted in twice as many resections being performed locally. Median survival for patients with oesophageal cancer has increased by 1 year and the 30-day mortality rate following resection has reduced by almost two thirds. Although other factors (such as improvements in oncological treatments, staging and critical care management over the 15-year time period) have undoubtedly had roles to play in these improvements, the results of this study support the policy of centralisation of upper GI cancer services.

Continuous and intermittent CSF diversion after subarachnoid hemorrhage: a pilot study.

BACKGROUND: We examine two accepted methods of managing cerebrospinal fluid (CSF) drainage in patients following subarachnoid hemorrhage (SAH). The first is intermittent CSF drainage when intracranial pressure (ICP) reaches a pre-defined threshold (monitor-first) and the second is continuous CSF drainage (drain-first) at set pressure thresholds. This pilot study is designed to determine if there is a cause for a randomized study of comparing the two methods. METHODS: This prospective observational pilot study enrolled 37 patients with SAH and external ventricular drainage between October 2008 and August 2009. Patients were treated with one of two methods of ICP management (drain-first vs. monitor-first) according to the discretion of the admitting physician. RESULTS: There were no significant differences in baseline characteristics including age, gender, severity of neurological dysfunction, and radiographic findings between the two groups. The incidence of vasospasm was not different between the drain-first group (66.7%; 16 of 24 patients) and the monitor-first group (53.9%; 7 of 13 patients). CONCLUSION: This pilot study was neither powered, nor expected to detect a difference between groups. The results of this study provide support for the design and conduct of a randomized study to assess the impact of two methods of CSF diversion for patients with SAH.

Impact of portal vein embolization on expression of cancer stem cell markers in regenerated liver and colorectal liver metastases.

OBJECTIVE: Little is known about the expression of stem cell markers in normal liver and colorectal liver metastases (CLM). The aim of this paper is to assess whether patterns of stem cell marker expression differ between normal liver tissue and CLM and to determine whether a clinical model of liver regeneration induced by portal vein embolization (PVE) has any influence on these patterns of expression in both regenerated liver tissue and cancer. MATERIALS AND METHODS: Immunohistochemistry was used to provide semi-quantitative analysis of patterns of expression in tissue samples of liver and tumor tissue pre- and post-PVE in 23 patients with CLM. CD133, CD44 and Oct4 were studied. RESULTS: There was no expression of CD133, CD44 or Oct4 in normal liver tissue before PVE but there was high expression of CD133 and CD44 in CLM. PVE had no significant influence on stem cell marker expression either in regenerated liver tissue or in tumor when compared with pre-PVE samples. CONCLUSION: Liver regeneration following PVE does not seem to involve stem cells. Stem cell marker expression by CLM supports the stem cell theory of carcinogenesis which is not influenced by PVE.

Training strategies for IACUC members and the institutional official.

Institutions are required by federal laws and regulations to oversee and evaluate their programs, facilities, and procedures for using animals in research, teaching, and/or testing activities. These responsibilities are specifically charged to an institutional official (IO) and an institutional animal care and use committee (IACUC). Initially, the individuals tasked with these responsibilities seldom have the requisite knowledge or experience to fulfill their charges effectively. Furthermore, simply reading the regulatory requirements does not prepare the novice IO and IACUC members to effectively monitor and guide the program. As a result, many new IOs and IACUC members are managing their responsibilities with insufficient understanding of the laws, regulations, standards, and policies. Specific training strategies for inexperienced IACUC members are needed to help them understand their responsibilities for ensuring animal welfare through an effective, high-quality, and compliant animal care and use program that supports the critical research needed to improve human and animal health. Likewise, most IOs would benefit from training to help them better understand their responsibility for enhancing or maintaining the quality of the institution's animal care and use program. Education and training should begin with an orientation to the laws, regulations, standards, and policies. Continuing training and education are also important to keep abreast of the changes in the interpretation of these laws and regulations as well as the changes in veterinary science. For both the IO and the IACUC, understanding and acceptance of their authority and responsibilities are significant factors in establishing and maintaining a quality animal care and use program.

An unusually late presentation of neuroschistosomiasis.

Schistosomiasis is one of the most widespread parasitic infections in man. Neuroschistosomiasis, referring to schistosomal involvement of the central nervous system, is an uncommon but well recognised complication of schistosomal infection. The duration between time of infection and onset of neurological symptoms typically varies between weeks to months. We describe a case of transverse myelitis secondary to neuroschistosomiasis, presenting more than three years after the time of initial schistosomal infection, diagnosed and treated in the district general hospital setting.

Improved synthesis of the peripheral benzodiazepine receptor ligand [11C]DPA-713 using [11C]methyl triflate.

Recently, the pyrazolopyrimidine, [11C] N,N-Diethyl-2-[2-(4-methoxyphenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl]acetamide (DPA-713) has been reported as a new promising marker for the study of peripheral benzodiazepine receptors with positron emission tomography. In the present study, DPA-713 has been labelled from the corresponding nor-analogue using [11C]methyl triflate (CH3OTf). Conditions for HPLC were also modified to include physiological saline (aq. 0.9% NaCl)/ethanol:60/40 as mobile phase making it suitable for injection. The total time of radiosynthesis, including HPLC purification, was 18-20 min. This reported synthesis of [11C]DPA-713, using [11C]CH3OTf, resulted in an improved radiochemical yield (30-38%) compared to [11C]methyl iodide (CH3I) (9) with a simpler purification method. This ultimately enhances the potential of [11C]DPA-713 for further pharmacological and clinical evaluation. These improvements make this radioligand more suitable for automated synthesis which is of benefit where multi-dose preparations and repeated syntheses of radioligand are required.

Short-term adverse health effects in a community exposed to a large polyvinylchloride plastics fire.

The purpose of this study was the documentation of the short-term morbidity and mortality experiences of an urban community exposed to the airborne byproducts of a large polyvinylchloride plastics fire. The authors administered a survey to representatives of each household who had lived in an area evacuated during the fire. A time-series analysis was performed on emergency room visits and admissions for all hospitals in the city. Chloracne surveillance was instituted. Sixty-two percent of the individuals surveyed from the evacuation area reported no health concerns or symptoms related to the fire. Thirty-eight percent of the residents reported symptoms, and less than 2% of those surveyed reported that they sought medical attention for their health concerns. There was no evidence of increased hospital admissions or emergency room use during and immediately following the fire. No cases of chloracne were reported, and no deaths or serious injuries occurred during the fire. Polyvinylchloride plastics recycling plants pose potential health hazards to civilian populations. Public health authorities should be prepared to assess population health status rapidly and to disseminate relevant health information in a timely way during a crisis.

Antigenic and genetic analysis of equine influenza viruses from tropical Africa in 1991.

A detailed analysis of equine (H3N8) influenza viruses isolated in Nigeria during early 1991 has been undertaken. Antigenic analysis and the complete nucleotide sequence of the HA gene of three Nigerian equine influenza viruses A/eq/Ibadan/4/91, A/eq/Ibadan/6/91 and A/eq/Ibadan/9/91 are presented and limited sequence analysis of each of the genes encoding the internal polypeptides of the virus has been carried out. These results establish that, despite the geographical location from which these viruses were isolated, two were similar to the viruses which were concurrently causing disease in Europe in 1989 and 1991 and were related to viruses that have been predominating in horses since 1985. The third was more closely related to viruses isolated from 1991 onward in Europe but also in other parts of the globe. A comparison of the nucleotide sequence of two of the viruses isolated in Nigeria (A/eq/Ibadan/4/91 and A/eq/Ibadan/6/91) with a European strain (A/eq/Suffolk/89) showed limited variation in the haemagglutinin gene which caused amino acid substitutions in one of the antigenic sites: this mutation resulted in the potential production of a new glycosylation site in antigenic site A. The other Nigerian virus (A/eq/Ibadan/9/91) showed only a single one amino acid change from another European strain (A/eq/Arundel/12369/91). The two distinct Nigerian viruses had several amino acid substitutions in the antigenic sites of the haemagglutinin glycoprotein.