Liquid Chromatography Post-Column Oxidation (PCOX) Method for the Determination of Paralytic Shellfish Toxins in Mussels, Clams, Oysters, and Scallops: Collaborative Study

Sixteen laboratories participated in a collaborative study to evaluate method performance parameters of a liquid chromatographic method of analysis for paralytic shellfsh toxins (PST) in blue mussels (Mytilus edulis), soft shell clams (Mya arenaria), sea scallops (Placopectin magellanicus), and American oysters (Crassostrea virginicus). The specifc analogs tested included saxitoxin, neosaxitoxin, gonyautoxins-1 to -5, decarbamoyl-gonyautoxins-2 and -3, decarbamoyl-saxitoxin, and N-sulfocarbamoylgonyautoxin-2 and -3. This instrumental technique has been developed as a replacement for the current AOAC biological method (AOAC Offcial MethodSM 959.08) and an alternative to the pre-column oxidation LC method (AOAC Offcial MethodSM 2005.06). The method is based on reversed-phase liquid chromatography with post-column oxidation and fluorescence detection (excitation 330 nm and emission 390 nm). The shellfsh samples used in the study were prepared from the edible tissues of clams, mussels, oysters, and scallops to contain concentrations of PST representative of low, medium, and high toxicities and with varying profles of individual toxins. These concentrations are approximately equivalent to ½ maximum level (ML), ML, or 2×ML established by regulatory authorities (0.40, 0.80, and 1.60 mg STX·diHCl eq/kg, respectively). Recovery for the individual toxins ranged from 104 to 127%, and recovery of total toxin averaged 116%. Horwitz Ratio (HorRat) values for individual toxins in the materials included in the study were generally within the desired range of 0.3 to 2.0. For the estimation of total toxicity in the test materials, the reproducibility relative standard deviation ranged from 4.6 to 20%. A bridging study comparing the results from the study participants using the post-column oxidation (PCOX) method with the results obtained in the study director’s laboratory on the same test materials using the accepted reference method, the mouse bioassay (MBA; AOAC Offcial MethodSM 959.08), showed that the average ratio of results obtained from the two methods was 1.0. A good match of values was also achieved with a new certifed reference material. The results from this study demonstrated that the PCOX method is a suitable method of analysis for PST in shellfsh tissue and provides both an estimate of total toxicity, equivalent to that determined using the MBA AOAC Offcial MethodSM 959.08, and a detailed profle of the individual toxin present in the sample.

Quantitative Determination of Paralytic Shellfish Poisoning Toxins in Shellfish Using Prechromatographic Oxidation and Liquid Chromatography with Fluorescence Detection: Collaborative Study

A collaborative study was conducted for the determination of paralytic shellfish poisoning (PSP) toxins in shellfish. The method used liquid chromatography with fluorescence detection after prechromatographic oxidation of the toxins with hydrogen peroxide and periodate. The PSP toxins studied were saxitoxin (STX), neosaxitoxin (NEO), gonyautoxins 2 and 3 (GTX2,3; together), gonyautoxins 1 and 4 (GTX1,4; together), decarbamoyl saxitoxin (dcSTX), B-1 (GTX5), C-1 and C-2 (C1,2; together), and C-3 and C-4 (C3,4; together). B-2 (GTX6) toxin was also included, but for qualitative identification only. Mussels, both blank and naturally contaminated, were mixed and homogenized to provide a variety of PSP toxin mixtures and concentration levels. The same procedure was followed with clams, oysters, and scallops. Twenty-one test samples in total were sent to 21 collaborators who agreed to participate in the study. Results were obtained from 18 laboratories representing 14 different countries. It is recommended that the method be adopted First Action by AOAC INTERNATIONAL.

Abusive behaviour experienced by family carers from people with dementia: the CARD (caring for relatives with dementia) study

BACKGROUND

The authors report the first study of abusive behaviour by people with dementia towards their family carers. The authors hypothesised that while abusive behaviour would be associated with the carer reporting a less rewarding relationship, this could be mediated by the carer's coping style.

METHODS

The authors interviewed 220 consecutively referred family dementia carers from five UK Community Mental Health Teams, using the revised Modified Conflict Tactics Scale to measure abuse, and the Relationship Rewards Scale.

RESULTS

82 (37.3%) carers reported abuse from the care recipient 'at least sometimes' over the last 3 months. 80 (36.4%) reported psychologically, and 13 (5.9%) physically abusive behaviour. On average, current carer relationship rewards had decreased from premorbid levels (mean difference -1.5 (95% CI 1.8 to 1.2); p<0.001). The association between higher abuse score and lower current relationship rewards was mediated by dysfunctional coping use. In our final model, current relationship rewards were predicted by reporting a better past relationship (beta=0.66 (95% CI 0.55 to 0.77)), less abuse from the care recipient (beta=-0.39 (-0.65 to -0.13)) and fewer dysfunctional coping strategies (beta=-0.98 (-1.50 to-0.46)).

CONCLUSION

Over a third of family carers reported significant abuse from the people they cared for. Carers who reported more abuse also reported a greater deterioration in their relationship with the person with dementia. The extent to which carers used dysfunctional coping strategies partially explained this, suggesting that interventions to change the carers' coping styles might alleviate the impact of abusive behaviour.

The rise and fall of a psychiatric antenatal clinic: development of a perinatal psychiatric service linked directly to the provision of antenatal care

Usual referral pathways to psychiatric services can miss opportunities for timely intervention in maternal perinatal psychiatric ill health. Psychiatric illness leading to suicide is a significant factor in at least 10% of maternal deaths. Despite Royal College of Psychiatry and National Institute for Health and Clinical Excellence recommendations for specialist provision of perinatal mental health services, this remains sporadic and insufficient. We set out to develop a new integrated antenatal-psychiatric direct referral pathway and present a year of experience using this service model. The psychiatric service was delivered from within the antenatal clinic setting with a direct health-care professional (HCP) led referral pathway between 2003 and 2004. The service comprised one session per week of a senior psychiatric specialist registrar and provided three new patients and two follow-up appointments per week. During this period, a total of 75 referrals to the service were made with 57 individuals attending for an appointment. There was a range of diagnoses among the women who attended, with only 24% meeting eligibility criteria for referral to secondary psychiatric services. The majority diagnosis was depression. More severely ill women were not referred to this clinic by obstetric HCPs. In conclusion, this model for developing and delivering a specialist perinatal psychiatric service using direct links to antenatal medical care was not successful despite requiring minimal funding. Nevertheless, it has been used to inform development of a new perinatal service in keeping with the Royal College of Psychiatrists' recommendations and incorporating enhanced training of HCPs responsible for the referral pathway.

Systematic review of the effect of psychological interventions on family caregivers of people with dementia

BACKGROUND

Caregivers of people with dementia are at high risk of psychological morbidity and associated breakdown in care. Many psychologically based interventions have been designed to help caregivers of people with dementia. More work is needed to identify which, if any, are helpful for such caregivers.

METHOD

We conducted a systematic review of the immediate and long term efficacy of different types of psychological interventions for the psychological health of caregivers of people with dementia, using standardized criteria, to assist clinicians in implementing rational, evidence-based management recommendations. We reviewed studies examining the effects of any therapy derived from a psychological approach that satisfied pre-specified criteria. Using the Oxford Centre for Evidence-Based Medicine criteria we rated the quality of each study, extracted data and gave overall ratings to different types of intervention.

RESULTS

We identified 244 references in our search of which 62 met our inclusion criteria.

LIMITATIONS

Our findings are limited by lack of good quality evidence, with only ten level 1 studies identified.

CONCLUSIONS

We found excellent evidence for the efficacy of six or more sessions of individual behavioral management therapy centered on the care recipient's behavior in alleviating caregiver symptoms both immediately and for up to 32 months. Teaching caregivers coping strategies either individually or in a group also appeared effective in improving caregiver psychological health both immediately and for some months afterwards. Group interventions were less effective than individual interventions. Education about dementia by itself, group behavioral therapy and supportive therapy were not effective caregiver interventions.

Whose Quality of Life Is It Anyway?

Quality of life (QoL) is becoming an increasingly used outcome measure in both clinical practice and research. There are now more than 1000 scales available to measure QoL, and it is important that they are assessed for reliability and validity. This study aims to assess the reliability and validity of the Quality of Life-Alzheimer's Disease (QoL-AD) scale, which is dementia specific and brief and uses the patient's own responses. Two separate samples of people with dementia (sample 1, n = 60; sample 2, n = 201) were assessed. Five focus groups were conducted involving both people with dementia and their caregivers; the focus groups showed that people with dementia had higher hopes for their QoL than their caregivers did for them. Questionnaires about the scale were completed by 71 health care professionals working with people with dementia. The scale was found to have good content validity with no additional items required and all items necessary. It also correlated well with the Dementia Quality of Life scale (0.69) and with the Euroqol-5D scale (0.54), indicating good criterion concurrent validity. Construct validity was also good with the principal components analysis showing all 13 items of the QoL-AD loaded on component 1. Interrater reliability was excellent with all Cohen's kappa values >0.70. Internal consistency was excellent with a Cronbach's alpha coefficient of 0.82. Some people with severe dementia and a Mini-Mental State Examination score as low as 3 were able to satisfactorily complete the QoL-AD. The QoL-AD has very good psychometric properties and can be completed with people with a wide range of severity of dementia.

Clinical characteristics of chronic Creutzfeldt-Jakob disease

Chronic Creutzfeldt-Jakob disease, presenting in later life, may be difficult to distinguish from other dementing illnesses. Patients with this disease may lack the characteristic myoclonus and electroencephalographic complexes. We report four patients with a slowly progressive dementia who were misdiagnosed during life and had a spongiform encephalopathy at autopsy. All four patients had early extrapyramidal rigidity, primitive reflexes, and other neurologic signs. The presence of these neurologic findings early in the course of a dementia suggests that clinicians should consider chronic Creutzfeldt-Jakob disease, evaluate the patient with electroencephalographic studies, and emphasize universal tissue precautions.

Pick's disease versus Alzheimer's disease: a comparison of clinical characteristics

The clinical recognition of Pick's disease depends on its differentiation from Alzheimer's disease (AD). To identify distinguishing clinical features, we reviewed the clinical records of 21 patients with pathologically confirmed Pick's disease and matched them by sex, age of onset, and duration of dementia with 42 patients having pathologically confirmed AD. In the absence of temporal or frontal lobar atrophy on CTs, all the Pick patients and none of the AD patients had three of five clinical features: presenile onset (before age 65), an initial personality change, hyperorality, disinhibition, and roaming behavior. In addition, the Pick patients had a tendency toward reiterative and other speech disturbances. These findings suggest that Pick patients are potentially distinguishable from AD patients on the basis of clinical manifestations.