Mortality and histopathology in sheepshead minnow (Cyprinodon variegatus) larvae exposed to pectenotoxin-2 and Dinophysis acuminata.

Toxic species of the dinoflagellate genus Dinophysis can produce diarrheic toxins including okadaic acid (OA) and dinophysistoxins (DTXs), and the non-diarrheic pectenotoxins (PTXs). Okadaic acid and DTXs cause diarrheic shellfish poisoning (DSP) in human consumers, and also cause cytotoxic, immunotoxic and genotoxic effects in a variety of mollusks and fishes at different life stages in vitro. The possible effects of co-produced PTXs or live cells of Dinophysis to aquatic organisms, however, are less understood. Effects on an early life stage of sheepshead minnow (Cyprinodon variegatus), a common finfish in eastern USA estuaries, were evaluated using a 96-h toxicity bioassay. Three-week old larvae were exposed to PTX2 concentrations from 50 to 4000 nM, live Dinophysis acuminata culture (strain DAVA01), live cells resuspended in clean medium or culture filtrate. This D. acuminata strain produced mainly intracellular PTX2 (≈ 21 pg cell-1), with much lower levels of OA and dinophysistoxin-1. No mortality or gill damages were observed in larvae exposed to D. acuminata (from 5 to 5500 cells mL-1), resuspended cells and culture filtrate. However, exposure to purified PTX2 at intermediate to high concentrations (from 250 to 4000 nM) resulted in 8 to 100% mortality after 96 h (24-h LC50 of 1231 nM). Histopathology and transmission electron microscopy of fish exposed to intermediate to high PTX2 concentrations revealed important gill damage, including intercellular edema, necrosis and sloughing of gill respiratory epithelia, and damage to the osmoregulatory epithelium, including hypertrophy, proliferation, redistribution and necrosis of chloride cells. Tissue damage in gills is likely caused by the interaction of PTX2 with the actin cytoskeleton of the affected gill epithelia. Overall, the severe gill pathology observed following the PTX2 exposure suggested death was due to loss of respiratory and osmoregulatory functions in C. variegatus larvae.

Meta-analysis and systematic review of population-based epidemiological studies in idiopathic intracranial hypertension.

Idiopathic intracranial hypertension (IIH) is positively associated with obesity, mostly in young women. The global increase in obesity may influence the burden of IIH. Using the PubMed, Embase, MEDLINE and Web of Science databases, a meta-analysis and systematic review of epidemiological studies of IIH were performed up to June 2017. Temporal changes in IIH incidence were measured, and incidence rates of IIH were correlated with country-specific World Health Organization obesity rates. Prevalence data and shunting rates of IIH were recorded. The quality of epidemiological studies was assessed using the Standards of Reporting of Neurological Disorders (STROND) criteria. In 15 identified studies, there were 889 patients (87% women), mean age 29.8 years. The incidence of IIH ranged from 0.03 to 2.36 per 100 000 per year. The pooled incidence of IIH was 1.20 per 100 000 per year although there was very high heterogeneity (I2 98%). The incidence rates of IIH were correlated with country-specific prevalence of obesity (Spearman's correlation 0.82, P < 0.01). The prevalence of IIH was rarely recorded. A shunting procedure was reported in 8% of patients. STROND criteria were variably reported, median of 26.5 of 43 (range 16-35). IIH is a public health concern as increased obesity prevalence is associated with increased incidence of IIH. A better quality of epidemiological studies is required to improve understanding of IIH and inform health policy for IIH management.

Characterisation and in vitro stability of low-dose, lidocaine-loaded poly(vinyl alcohol)-tetrahydroxyborate hydrogels.

Poly(vinyl alcohol) hydrogels cross-linked with the tetrahydroxyborate anion possess textural and rheological properties that can be used as novel drug-loaded vehicles for application to traumatic wounds. However, addition of soluble drug substances causes concentration-dependent phase separation and rheological changes. The aim of this work was to investigate the effect of adding a local anaesthetic, but keeping the concentration low in an attempt to prevent these changes. Cross-linked hydrogels prepared from three grades of poly(vinyl alcohol) were characterised rheologically. Temperature sweep studies showed an elevated complex viscosity upon moving from 25°C to 80°C, which remained high for 48 h following completion of the cycle. Adhesion to model dermal surfaces achieved a maximum of 2.62 N cm(-2) and were greater than that observed to epidermal substrates, with a strong dependence on the rate of detachment used during testing. An optimised formulation (6% w/w PVA (31-50; 99) and 2% w/w THB) containing lidocaine hydrochloride loaded to an upper maximum concentration of 1.5% w/w was assessed for phase separation and drug crystallisation. After six months, crystallisation was present in formulations containing 0.7% and 1.5% lidocaine HCl. Changes in pH in response to increases in lidocaine loading were low. Drug release was shown to operate via a non-Fickian process for all three concentrations, with 60% occurring after approximately 24h. It can be concluded that using a low concentration of lidocaine hydrochloride in hydrogels based on poly(vinyl alcohol) will result in crystallisation. Furthermore, these hydrogels are unlikely to induce rapid anaesthesia due to the low loading and slow release kinetics.

Optimising neuroimaging effectiveness in a district general hospital.

BACKGROUND: Diagnostic accuracy in neurology frequently depends on clinical assessment and neuroimaging interpretation. We assessed neuroimaging discrepancy rates in reported findings between general radiologists and neuroradiologists among patients from a district general hospital (DGH). METHODS: A neuroradiologist's report was sought on selected DGH patients over 28 months. Pre-planned outcomes included comparisons of primary findings (main diagnosis or abnormality), secondary findings (differential diagnoses and incidental findings) and advice from neuroradiologists for further investigations. RESULTS: A total of 233 patients (119 men and 114 women), mean age 47.2 (SD 17.8) years were studied: 43 had a computed tomography (CT) brain scan only, 37 had CT and magnetic resonance imaging (MRI) scans and 153 had only MRI scans. Discrepancies in the primary diagnosis/abnormality were identified in 33 patients (14.2%). This included 7 of 43 patients (16.3%) who had a CT brain scan as their only neuroimaging. Secondary outcomes differed in 50 patients (21.5%). Neuroradiologists recommended further neuroimaging for 29 patients (12.4%). The most common discrepancies in the primary diagnosis/abnormality were misinterpreting normal for hippocampal sclerosis and missed posterior fossa lesions. There was no evidence of temporal changes in discrepancy rates. CONCLUSIONS: Selecting CT and MR neuroimaging studies from general hospitals for reviewing by neuroradiologists is an important and effective way of optimising management of neurological patients.

Discovery of gymnodimine fatty acid ester metabolites in shellfish using liquid chromatography/mass spectrometry.

RATIONALE: Gymnodimines (GYMs) are fast-acting toxins that belong to the cyclic imine group, a subclass of lipophilic marine toxins. GYMs are considered to be emerging toxins but have not yet been linked to incidents of human poisoning, Limited knowledge on the metabolism of GYMs means that a proper risk assessment has not been possible and caution must be taken when establishing the relevance of GYMs in terms of food safety of marine products. METHODS: A series of mass spectrometric experiments involving precursor and product ion scans, selected reaction monitoring (SRM), and high-resolution mass spectrometry (MS) were used to detect and confirm 10-O-acyl esters of gymnodimine-A (1). RESULTS: We have detected for the first time the presence of a range of acyl ester derivatives of GYMs in shellfish samples from the Gulf of Gabes, Tunisia. The MS fragmentation pathways of 1 and its esters were also elucidated. Partial synthesis of a palmitic acid ester of 1 facilitated confirmation of identity and calibration of SRM analyses. Evidence of acyl ester metabolites of gymnodimine-B and -C was also obtained. CONCLUSIONS: A semi-quantitative analysis indicated that the majority of GYMs present in the sample were in the acylated form (>90%), suggesting that these compounds must not be neglected when trying to understand the risks associated with GYMs. There is a clear need for toxicology studies on these esters and assessment of bio-availability to humans.

State of the art in benefit-risk analysis: medicines.

Benefit-risk assessment in medicine has been a valuable tool in the regulation of medicines since the 1960s. Benefit-risk assessment takes place in multiple stages during a medicine's life-cycle and can be conducted in a variety of ways, using methods ranging from qualitative to quantitative. Each benefit-risk assessment method is subject to its own specific strengths and limitations. Despite its widespread and long-time use, benefit-risk assessment in medicine is subject to debate and suffers from a number of limitations and is currently still under development. This state of the art review paper will discuss the various aspects and approaches to benefit-risk assessment in medicine in a chronological pathway. The review will discuss all types of benefit-risk assessment a medicinal product will undergo during its lifecycle, from Phase I clinical trials to post-marketing surveillance and health technology assessment for inclusion in public formularies. The benefit-risk profile of a drug is dynamic and differs for different indications and patient groups. In the end of this review we conclude benefit-risk analysis in medicine is a developed practice that is subject to continuous improvement and modernisation. Improvement not only in methodology, but also in cooperation between organizations can improve benefit-risk assessment.

Quantitative determination of marine lipophilic toxins in mussels, oysters and cockles using liquid chromatography-mass spectrometry: inter-laboratory validation study.

Thirteen laboratories participated in an inter-laboratory study to evaluate the method performance characteristics of a liquid chromatography-tandem mass spectrometric method (LC-MS/MS) for marine lipophilic shellfish toxins. Method performance characteristics were evaluated for mussel (Mytilus edulis), oyster (Crassostrea gigas) and cockle (Cerastoderma edule) matrices. The specific toxin analogues tested included okadaic acid (OA), dinophysistoxins-1 and -2 (DTX1, -2), azaspiracids-1, -2 and -3 (AZA1, -2, -3), pectenotoxin-2 (PTX2), yessotoxin (YTX), and 45-OH-yessotoxin (45-OH-YTX). The instrumental technique was developed as an alternative to the still widely applied biological methods (mouse or rat bioassay). Validation was conducted according to the AOAC-harmonised protocol for the design, conduct and interpretation of method-performance studies. Eight different test materials were sent as blind duplicates to the participating laboratories. Twelve laboratories returned results that were accepted to be included in the statistical evaluation. The method precision was expressed as HORRATs. For the individual toxins (except for 45-OH-YTX) HORRATs were found to be ≤1.8 (median HORRAT=0.8) in all tested materials. The recoveries of OA-, AZA- and YTX-group toxins were within the range of 80-108% and PTX2 was within the range of 62-93%. Based on the acceptable values for precision and recovery, it was concluded that the method is suitable for official control purposes to quantitatively determine OA/DTXs, AZAs, YTXs and PTX2 in shellfish.

A behavioral weight-loss intervention for persons with serious mental illness in psychiatric rehabilitation centers.

OBJECTIVE: Overweight and obesity are epidemic in populations with serious mental illnesses. We developed and pilot-tested a behavioral weight-loss intervention appropriately tailored for persons with serious mental disorders. METHODS: We conducted a single-arm pilot study in two psychiatric rehabilitation day programs in Maryland, and enrolled 63 overweight or obese adults. The 6-month intervention provided group and individual weight management and group physical activity classes. The primary outcome was weight change from baseline to 6 months. RESULTS: A total of 64% of those potentially eligible enrolled at the centers. The mean age was 43.7 years; 56% were women; 49% were white; and over half had schizophrenia or a schizoaffective disorder. One-third had hypertension and one-fifth had diabetes. In total, 52 (82%) completed the study; others were discharged from psychiatric centers before completion of the study. Average attendance across all weight management sessions was 70% (87% on days participants attended the center) and 59% for physical activity classes (74% on days participants attended the center). From a baseline mean of 210.9 lbs (s.d. 43.9), average weight loss for 52 participants was 4.5 lb (s.d. 12.8) (P<0.014). On average, participants lost 1.9% of body weight. Mean waist circumference change was 3.1 cm (s.d. 5.6). Participants on average increased the distance on the 6-minute walk test by 8%. CONCLUSION: This pilot study documents the feasibility and preliminary efficacy of a behavioral weight-loss intervention in adults with serious mental illness who were attendees at psychiatric rehabilitation centers. The results may have implications for developing weight-loss interventions in other institutional settings such as schools or nursing homes.

Optimisation of storage conditions for maintaining culturability of penicillin-susceptible and penicillin-resistant isolates of Streptococcus pneumoniae in transport medium.

Methods employed by the World Health Organization (WHO) are used during this study to determine the optimum storage conditions for maintaining the culturability of Streptococcus pneumoniae in skimmed milk, tryptone, glucose and glycerin (STGG) transport medium. A comparison of S. pneumoniae strains sensitive and resistant to penicillin showed no significant difference in their survival ability in STGG medium. Furthermore, it is confirmed that storage at -70 degrees C remains most effective for maintaining viability by culture of S. pneumoniae. Storage at -20 degrees C would only be acceptable in the short-term, while storage at +4 degrees C is not recommended. Of note, this study has shown STGG medium at room temperature to be an efficient growth medium for pneumococci in the short-term. This work will help to establish robust sampling protocols when performing community studies to ensure culturability of comparison between community and laboratory pneumococci survival.

An overview of techniques used to measure wound area and volume.

If wound area is to be used as an indicator of healing, then it is vital that all measurements are accurate and consistent. This depends largely on the measurement tool used. This paper offers an insight into the available evidence.

Clinical and immunohistochemical assessment of vulval intraepithelial neoplasia following photodynamic therapy using a novel bioadhesive patch-type system loaded with 5-aminolevulinic acid.

BACKGROUND: The work in this study appraised photodynamic treatment (PDT) as a treatment method for vulval intraepithelial neoplasia (VIN) using a novel bioadhesive patch to deliver aminolevulinic acid. An analysis of changes in expression of apoptotic and cell cycle proteins (p53, p21, Mdm2, Blc-2, Bax, Ki-67) in response to PDT was evaluated. METHODS: PDT was performed using non-laser light, either as a one or two-cycle treatment, with clinical and pathological assessment following after 6 weeks. Twenty-three patients with 25 VIN lesions underwent 49 cycles of PDT. Patches were designed to conform to uneven vulval skin and contained 38 mg cm(-2) aminolevulinic acid. Assessment was carried out at 6 weeks post-treatment. Patient-based treatment assessment, along with clinical and pathological changes, were monitored. Immunohistochemical staining was used to elucidate a possible biomolecular basis for induced cellular changes. RESULTS: Most patients (52%) reported a symptomatic response, with normal pathology restored in 38% of lesions. The patch was easy to apply and remove, causing minimal discomfort. Fluorescence inspection confirmed protoporphyrin accumulation. Pain during implementation of PDT was problematic, necessitating some form of local analgesia. Changes in expression of cell cycle and apoptotic-related proteins suggested involvement of apoptotic pathways. Down regulation of p21 and inverse changes in Bcl-2 and Bax were key findings. CONCLUSION: Treatment of VIN lesions using a novel bioadhesive patch induced changes in cell cycle and apoptotic proteins in response to PDT with possible utilisation of apoptotic pathways. The efficacy of PDT in treating VIN could be improved by a better understanding of these apoptotic mechanisms, the influence of factors, such as HPV status, and of the need for effective pain management.

Driving after a transient ischaemic attack or minor stroke.

The frequency of adherence to the UK Driver and Vehicle Licensing Authority (DVLA) guidelines for patients referred to a neurovascular clinic is not known. Of 166 consecutive patients, 95 (57.2%) had a group 1 licence and 71 (42.7%) drove within a month of the event. Fifty of 85 (59%) transient ischaemic attack (TIA)/minor stroke patients had a licence and 30 (35%) drove within a month of the TIA/stroke. Compliance with DVLA driving guidelines is poor among patients referred to hospital with suspected TIA or minor strokes.

Potential for quality improvement of acute stroke management in a district general hospital.

BACKGROUND: Stroke units and thrombolysis are evidence based treatments for stroke patients. Few studies have prospectively assessed the success of, and obstacles to implementation of such strategies in patients admitted to district general hospitals. OBJECTIVE: To document delays in admissions of acute stroke patients to hospital, failures in accessing a stroke unit and the clinical impact of missed opportunities for intervention in acute stroke patients. DESIGN, SETTING AND METHODS: Prospective observational study in a district general hospital in Northern Ireland. Delays, demographic details, risk factors, stroke severity and classification were recorded prospectively in all stroke patients admitted to a district general hospital from 22 March 2004 until 21 March 2005. Using established numbers needed to treat to prevent disability or death, the clinical impact of the lost opportunities was determined. RESULTS: Of 171 acute stroke patients 115 (67%) spent some or all of their hospital stay in a stroke unit. Less severe strokes, living alone and attending a general practitioner all independently delayed hospital admission. Nineteen (12.5%) ischaemic stroke patients would have been eligible for intravenous thrombolysis treatment. Admitting all patients to the stroke unit would have gained independence for two patients, allowed two more patients to live at home, and prevented one death. Failure to thrombolyse eligible acute ischaemic stroke patients resulted in six patients having more disability, two of whom may have lost their independence. CONCLUSIONS: Improved stroke unit access is required in this district general hospital. Reorganisation of acute stroke services should allow thrombolysis for acute ischaemic stroke in most district general hospitals.

Comparison of the cidal activity of tea tree oil and terpinen-4-ol against clinical bacterial skin isolates and human fibroblast cells.

AIMS: The aim of this study was to compare both the antimicrobial activity of terpinen-4-ol and tea tree oil (TTO) against clinical skin isolates of meticillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (CoNS) and their toxicity against human fibroblast cells. METHODS AND RESULTS: Antimicrobial activity was compared by using broth microdilution and quantitative in vitro time-kill test methods. Terpinen-4-ol exhibited significantly greater bacteriostatic and bactericidal activity, as measured by minimum inhibitory and bactericidal concentrations, respectively, than TTO against both MRSA and CoNS isolates. Although not statistically significant, time-kill studies also clearly showed that terpinen-4-ol exhibited greater antimicrobial activity than TTO. Comparison of the toxicity of terpinen-4-ol and TTO against human fibroblasts revealed that neither agent, at the concentrations tested, were toxic over the 24-h test period. CONCLUSIONS: Terpinen-4-ol is a more potent antibacterial agent against MRSA and CoNS isolates than TTO with neither agent exhibiting toxicity to fibroblast cells at the concentrations tested. SIGNIFICANCE AND IMPACT OF THE STUDY: Terpinen-4-ol should be considered for inclusion as a single agent in products formulated for topical treatment of MRSA infection. However, further work would initially be required to ensure that resistance would not develop with the use of terpinen-4-ol as a single agent.

Association between early life history of respiratory disease and morbidity and mortality in adulthood.

BACKGROUND: Early life exposure to respiratory diseases is associated with lung impairment in adulthood. The objective of this study was to investigate morbidity, and respiratory and other cause specific mortality, among people who reported a medical history of bronchitis, pneumonia and asthma early in life. METHODS: We studied an historical cohort of male students who attended Glasgow University between 1948 and 1968 and for whom long term follow-up and cause specific mortality were available (9544 students, 1553 deaths). A medical history of respiratory diseases, including bronchitis, pneumonia and asthma, along with other disease risk factors and socioeconomic conditions, were collected during university health examinations. A subsample responded to a postal follow-up in adulthood (n = 4044), which included respiratory and other chronic disease questions. RESULTS: A medical history of a respiratory disease (bronchitis, pneumonia and asthma) in early life was associated with a 57% greater risk of overall respiratory disease mortality in adulthood and a more than twofold increase in chronic obstructive pulmonary disease mortality (fully adjusted hazard ratio (HR) 2.37; 95% CI 1.16, 4.83). In addition, students reporting a history of bronchitis had a 38% higher risk of cardiovascular disease mortality (95% CI 1.06, 1.80). Respiratory disease in early life was also associated with a higher risk in adulthood of chronic phlegm, dyspnoea and doctor's diagnosis of asthma, bronchitis and emphysema (adjusted odds ratios ranging from 1.40 to 6.95 for these outcomes). CONCLUSION: An early life history of respiratory diseases is associated with higher mortality and morbidity risk in adulthood in men, the associations being seen particularly for respiratory related and cardiovascular deaths among those with a history of bronchitis. All early life respiratory diseases appeared to be negatively associated with later adult respiratory health.

Incorporation of novel 1-alkylcarbonyloxymethyl prodrugs of 5-fluorouracil into poly(lactide-co-glycolide) nanoparticles.

Incorporation of 1-alkylcarbonyloxymethyl prodrugs of 5FU into poly(lactide-co-glycolide) nanoparticles using nanoprecipitation methods gave increased loading efficiencies over that obtained using the parent drug substance. SEM studies revealed spherical nanoparticles of around 200nm in diameter, corresponding well with measurements made using photon correlation spectroscopy. The C(7) prodrug gave the best mean loading of 47.23%, which compared favourably to 3.68% loading achieved with 5FU. Loading efficiency was seen to follow the hydrophilic-lipophilic balance in the homologue series, where increases in lipophilicities alone were not good predictors of loading. Drug release, in terms of resultant 5FU concentration, was monitored using a flow-through dissolution apparatus. Cumulative drug release from nanoparticles loaded with the C(5) prodrug was linear over 6h, with approximately 14% of the total available 5FU dose released and with no evidence of a burst effect. The flux profile of the C(5)-loaded nanoparticles showed an initial peak in flux in the first sampling interval, but became linear for the remainder of the release phase. C(7)-loaded nanoparticles released considerably less (4% in 6h) with a similar flux pattern to that seen with the C(5) prodrug. The C(9)-loaded nanoparticles released less than 1% of the available 5FU over 6h, with a similar zero-order profile. The C(7) prodrug was deemed to be the prodrug of choice, achieving the highest loadings and releasing 5FU, following hydrolysis, in a zero-order fashion over a period of at least 6h. Given the lack of burst effect and steady-state flux conditions, this nanoparticulate formulation offers a better dosing strategy for sustained intravenous use when compared to that arising from nanoparticles made by direct incorporation of 5FU.

Relationship between Helicobacter pylori infection and gastric atrophy and the stages of the oesophageal inflammation, metaplasia, adenocarcinoma sequence: results from the FINBAR case-control study.

OBJECTIVE: A number of studies have shown an inverse association between infection with Helicobacter pylori and oesophageal adenocarcinoma (OAC). The mechanism of the apparent protection against OAC by H pylori infection and, in particular, the role of gastric atrophy is disputed. The relationship between all stages of the oesophageal inflammation, metaplasia, adenocarcinoma sequence and H pylori infection and gastric atrophy was explored. METHODS: A case-control study involving 260 population controls, 227 OAC, 224 Barrett's oesophagus (BO) and 230 reflux oesophagitis (RO) patients recruited within Ireland was carried out. H pylori and CagA (cytotoxin-associated gene product A) infection was diagnosed serologically by western blot, and pepsinogen I and II levels were measured by enzyme immunoassay. Gastric atrophy was defined as a pepsinogen I/II ratio of <3. RESULTS: H pylori seropositivity was inversely associated with OAC, BO and RO; adjusted ORs (95% CIs), 0.49 (0.31 to 0.76), 0.35 (0.22 to 0.56) and 0.42 (0.27 to 0.65), respectively. Gastric atrophy was uncommon (5.3% of all subjects), but was inversely associated with non-junctional OAC, BO and RO; adjusted ORs (95% CIs), 0.34 (0.10 to 1.24), 0.23 (0.05 to 0.96) and 0.27 (0.08 to 0.88), respectively. Inverse associations between H pylori and the disease states remained in gastric atrophy-negative patients. CONCLUSION: H pylori infection and gastric atrophy are associated with a reduced risk of OAC, BO and RO. While use of the pepsinogen I/II ratio as a marker for gastric atrophy has limitations, these data suggest that although gastric atrophy is involved it may not fully explain the inverse associations observed with H pylori infection.