A chemiluminescence nanosensor to monitor lipid peroxidation

Coumarin C343 (C(16)H(15)NO(4)), a dye used to enhance the weak chemiluminescence associated with lipid peroxidation, was conjugated to silica nanoparticles and entrapped in a sol-gel matrix to produce a nanosensor capable of enhancing low-level chemiluminescence by approximately 100%.

Slc11a1 (formerly NRAMP1) gene modulates both acute inflammatory reactions and pristane-induced arthritis in mice

Mice selected for the maximum acute inflammatory reaction (AIRmax) are highly susceptible to pristane-induced arthritis (PIA), whereas mice selected for the minimum response (AIRmin) are resistant. These lines show distinct patterns of leukocyte infiltration and R and S allele frequency disequilibrium of the solute carrier family 11a member 1 (Slc11a1) gene. In order to study the interactions of the Slc11a1 R and S alleles with the inflammation modulating Quantitative Trait Loci (QTL) during PIA development, homozygous AIRmax(RR), AIRmax(SS), AIRmin(RR) and AIRmin(SS) lines were produced by genotype-assisted breedings. These mice received two intraperitoneal injections of 0.5 ml pristane at 60-day intervals, and the subsequent development of arthritis was assessed for 210 days. Cytokine-secreting cell profiles were investigated using enzyme-linked immunospot. Arthritis incidence in AIRmax(RR) mice reached 29%, whereas PIA incidence in AIRmax(SS) mice was 70% by day 180. AIRmin(RR) mice were resistant, whereas 13.3% of AIRmin(SS) mice became arthritic. The presence of the defective S allele also increased arthritis severity, although acute inflammation was higher in mice bearing the R allele. A predominant Th0/Th2-type response in Slc11a1(SS) mice was observed. These results indicate that Slc11a1 is a strong candidate for the QTL modulating acute inflammation and for PIA.

Lack of evidence for elevated obstetric complications in childhood onset schizophrenia

BACKGROUND

Pre-, peri-, and postnatal obstetric complications (OC) are reported to be more frequent in adult patients with schizophrenia and have been linked to both greater severity and to "earlier" age of onset (before either age 18 or 22) in studies of adult patients. We hypothesized that by extrapolation, patients with childhood-onset schizophrenia (COS), with very early onset and very severe illness, would have had more numerous or more salient OC compared with their healthy siblings.

METHODS

We compared the obstetric records of 60 COS children and 48 healthy siblings using the Columbia Obstetrics Complication Scale, a comprehensive measurement scale consisting of 37 variables having included a separate scale for fetal hypoxia.

RESULTS

Patients with COS did not have a higher incidence of OC than the healthy sibling control group with the exception of increased incidence of maternal vomiting.

CONCLUSIONS

Obstetric complications, with the possible exception of maternal vomiting, are unlikely to play a major role in the etiopathogenesis of childhood-onset schizophrenia.

GAD1 (2q31.1), which encodes glutamic acid decarboxylase (GAD67), is associated with childhood-onset schizophrenia and cortical gray matter volume loss

Postmortem brain studies have shown deficits in the cortical gamma-aminobutyric acid (GABA) system in schizophrenic individuals. Expression studies have shown a decrease in the major GABA-synthesizing enzyme (glutamic acid decarboxylase (GAD67) mRNA levels in neurons in dorsolateral prefrontal cortex in schizophrenics relative to controls. In the present study, SNPs in and around the GAD1 gene, which encodes the protein GAD67, were tested on a rare, severely ill group of children and adolescents with childhood-onset schizophrenia (COS) (n=72), in a family-based association analysis. Compared to adult-onset samples, the COS sample has evidence for more salient familial, and perhaps genetic, risk factors for schizophrenia, as well as evidence for frontal cortical hypofunction, and greater decline in cortical gray matter volume on anatomic brain MRI scans during adolescence. We performed family-based TDT and haplotype association analyses of the clinical phenotype, as well as association analyses with endophenotypes using the QTDT program. Three adjacent SNPs in the 5' upstream region of GAD1 showed a positive pairwise association with illness in these families (P=0.022-0.057). Significant transmission distortion of 4-SNP haplotypes was also observed (P=0.003-0.008). Quantitative trait TDT analyses showed an intriguing association between several SNPs and increased rate of frontal gray matter loss. These observations, when taken together with the positive results reported recently in two independent adult-onset schizophrenia pedigree samples, suggest that the gene encoding GAD67 may be a common risk factor for schizophrenia.

Polymorphisms in the 13q33.2 gene G72/G30 are associated with childhood-onset schizophrenia and psychosis not otherwise specified

BACKGROUND

Childhood-onset schizophrenia (COS), defined as onset of psychotic symptoms by age 12 years, is a rare and severe form of the disorder that seems to be clinically and neurobiologically continuous with the adult disorder.

METHODS

We studied a rare cohort consisting of 98 probands; 71 of these probands received a DSM-defined diagnosis of schizophrenia, and the remaining 27 were diagnosed as psychosis not otherwise specified (NOS) (upon 2-6 year follow-up, 13 have subsequently developed bipolar disorder). Two overlapping genes, G72 and G30 on 13q33.2, were identified through linkage-disequilibrium-based positional cloning. Single nucleotide polymorphisms (SNPs) at the G72/G30 locus were independently associated with both bipolar illness and schizophrenia. We analyzed SNPs at this locus with a family-based transmission disequilibrium test (TDT) and haplotype analyses for the discrete trait, as well as quantitative TDT for intermediate phenotypes, using the 88 probands (including COS and psychosis-NOS) with parental participation.

RESULTS

We observed significant pairwise and haplotype associations between SNPs at the G72/G30 locus and psychotic illness. Furthermore, these markers showed associations with scores on a premorbid phenotype measured by the Autism Screening Questionnaire, and with age of onset.

CONCLUSIONS

These findings, although limited by potential referral bias, confirm and strengthen previous reports that G72/G30 is a susceptibility locus both for schizophrenia and bipolar disorder.

Fitness reduction and potential extinction of wild populations of Atlantic salmon, Salmo salar, as a result of interactions with escaped farm salmon

The high level of escapes from Atlantic salmon farms, up to two million fishes per year in the North Atlantic, has raised concern about the potential impact on wild populations. We report on a two-generation experiment examining the estimated lifetime successes, relative to wild natives, of farm, F(1) and F(2) hybrids and BC(1) backcrosses to wild and farm salmon. Offspring of farm and "hybrids" (i.e. all F(1), F(2) and BC(1) groups) showed reduced survival compared with wild salmon but grew faster as juveniles and displaced wild parr, which as a group were significantly smaller. Where suitable habitat for these emigrant parr is absent, this competition would result in reduced wild smolt production. In the experimental conditions, where emigrants survived downstream, the relative estimated lifetime success ranged from 2% (farm) to 89% (BC(1) wild) of that of wild salmon, indicating additive genetic variation for survival. Wild salmon primarily returned to fresh water after one sea winter (1SW) but farm and 'hybrids' produced proportionately more 2SW salmon. However, lower overall survival means that this would result in reduced recruitment despite increased 2SW fecundity. We thus demonstrate that interaction of farm with wild salmon results in lowered fitness, with repeated escapes causing cumulative fitness depression and potentially an extinction vortex in vulnerable populations.

The osteodystrophy of mucolipidosis type III and the effects of intravenous pamidronate treatment

Mucolipidosis type III (ML III; McKusick 252600) is a rare lysosomal storage disease in which skeletal involvement is prominent, in particular the destruction of vertebral bodies and the femoral heads. We describe studies in two siblings with ML III that suggest the presence of a distinct metabolic bone disorder. Biochemical indices of bone turnover were increased, and transiliac bone biopsy demonstrated both trabecular osteopenia and marked subperiosteal bone resorption. Intravenous pamidronate treatment given monthly for a year was well tolerated and produced dramatic clinical effects, with reduction in bone pain and improvements in mobility, despite incomplete suppression of bone resorption as assessed by biochemical, radiographic and histological criteria. Bisphosphonate therapy may have an important role in the management of bone pain in ML III, as it does in the related lysosomal disorder of Gaucher disease.

Eikenella corrodens infective endocarditis in a previously healthy non-drug user

Reported here is a case of Eikenella corrodens aortic valve infective endocarditis presenting as a stroke in a previously healthy 31-year-old man. The patient had no evidence of structural heart disease and reported no history of intravenous drug use or recent dental treatment. There are no other cases reported in the available literature in which this microorganism has caused endocarditis in the absence of recognised risk factors.

Socio-demographic and health system factors in relation to exclusive breast-feeding in Tobago

To determine the prevalence and significant correlates of exclusive breast-feeding among nursing mothers, we conducted a survey among nursing mothers attending the Wellness Baby Clinic in Tobago from July 1 to December 1, 1998. A random sample of 151 mothers had face-to-face interviews with a standardized pretested questionnaire. Our results suggest that 48.3% and 20.8% of infants were exclusively breast-fed at two and four months respectively. Univariate logistic regression analyses showed that exclusive breast-feeding at two months was significantly positively associated with years of schooling completed by the mother, frequency of prenatal visits, mode of breast-feeding, mother's knowledge of the recommended duration of breast-feeding, and occupation of the child's father. Exclusive breast-feeding at four months was significantly positively associated with mother's age, years of schooling completed by the mother, frequency of prenatal visits, mother's knowledge of the recommended duration of breast-feeding, years of schooling completed by the child's father and occupation of the child's father. In multivariate logistic analyses, adjusting simultaneously for all relevant explanatory variables, exclusive breast-feeding at two months was significantly positively associated with frequency of prenatal clinic visits, mode of breast-feeding, mother's knowledge of the recommended duration of breast-feeding and occupation of the child's father. In addition, exclusive breast-feeding at four months was significantly positively associated with frequency of prenatal clinic visits, length of hospital stay, mother's knowledge of recommended duration of breast-feeding, years of schooling completed by the child's father, family structure and inversely associated with mother's age. In this sample, parental socio-demographic characteristics and health system factors were associated with subsequent infant feeding practices.

An open-label trial of tomoxetine in pediatric attention deficit hyperactivity disorder

OBJECTIVE

To collect pilot data assessing the safety, tolerability, and efficacy of tomoxetine, a nonstimulant norepinephrine enhancer, in pediatric attention deficit hyperactivity disorder (ADHD).

METHODS

An open-label trial of tomoxetine in pediatric ADHD was conducted as part of a multisite clinical trial. Following a baseline assessment, an ascending dose titration was completed during 10 weekly visits.

RESULTS

Ten subjects were enrolled at baseline, with eight completing the study. Seven of the eight remaining subjects met efficacy criteria. Significant decreases in symptom severity ratings by parents and study investigators were found. The medication was well tolerated, with transient appetite suppression the most frequently reported side effect. However, subjects' weights remained stable across study visits.

DISCUSSION

These preliminary findings suggest that tomoxetine may hold promise as a treatment for pediatric ADHD.

Further modification to soft drinks to minimise erosion. A study in situ

Soft drinks have been successfully modified to reduce enamel erosion. The aim of this study was to further modify an original low erosive blackcurrant drink product by the addition of a gum, to manipulate more favourably other drink parameters. The study was a single-blind, randomised four treatment crossover design involving 12 healthy volunteers. During 10 working-day study periods, subjects wore enamel samples in the mid palatal region of a removable appliance. Specimens were taped to expose a 2-mm enamel window. The drinks under test were: (1) Orange juice, (2) Original blackcurrant drink, (3) Water, and (4) Experimental blackcurrant drink. Drinks were imbibed at 250-ml volumes 4 times a day during appliance wearing from 09.00 to 17.00. Appliances were removed at lunchtime. Measurements of specimens were made at baseline, 2, 5 and 10 days using a profilometer. One 5-day and one 10-day specimen from each subject during each treatment were ultrasonicated. Significant differences, in erosion between drinks, were seen at days 5 and 10. Comparisons of preselected pairs of drinks of interest showed significantly reduced erosion by the two blackcurrant drinks compared to orange juice with no significant differences from water. The original blackcurrant drink produced significantly less erosion than the experimental drink. Ultrasonication removed enamel from the Orange juice specimens but very little from those exposed to water and the two blackcurrant drinks. Extrapolating the effects of both blackcurrant drinks suggested that alone they should not cause significant clinical erosion in a lifetime's intake of 1 litre per day.

Dimensional perspective on the recognition of depressive symptoms in primary care: The Hampshire Depression Project 3

BACKGROUND

Most studies of the recognition of depression in primary care have used a categorical definition of depression. This may overstate the extent of the problem.

AIMS

Our objective was to investigate the relationship between severity and recognition of depression, and its modification by patient and practitioner characteristics.

METHOD

An association study in multiple consecutive adult cohorts of 18 414 primary care consultations drawn from a representative sample of 156 general practitioners in Hampshire, UK.

RESULTS

There was a curvilinear relationship between the severity of depression and practitioners' ratings of depression. One case of probable depression was missed in every 28.6 consultations. Anxiety and unemployment altered the chances of recognition, but age, gender and deprivation scores did not.

CONCLUSIONS

A dimensional approach to severity of depression shows that general practitioners may be better able to recognise depression than previous categorical studies have suggested. Efforts to improve the care of depression should therefore focus on doctors who have been shown to have difficulty making the diagnosis and on improving the treatment of identified patients.

Exploring the use of an alginate dressing for diabetic foot ulcers

Few studies have investigated the use of dressings on patients with diabetic foot ulceration. This paper reports the results of a non-comparative, two-centre study investigating the performance characteristics of SeaSorb dressing in patients with this condition. This was an exploratory study to determine the potential use of this dressing, and not a large randomised control trial. All patients had diabetic foot ulceration of 1 cm or more in diameter, classified as Wagner grade I or II, with an ankle brachial pressure index of > 0.4. The investigators carried out objective assessments including photography and ulcer tracing as well as subjective assessments of exudate levels, wound bed condition, peri-ulcer skin condition, ease of application and removal of the dressing, dressing conformability, discomfort during dressing application and removal, and clinical signs of infection. Investigators recruited 41 patients in two sites (31 in site one and 10 in site two). Of these, the findings relating to 39 patients could be evaluated. The patients were treated for a maximum of six weeks or until the ulcer healed. The study found that 28.2% (11/39) of the ulcers healed within the six-week period. Overall, there was a significant reduction in mean ulcer area from 2.8 cm 2 to 1.02 cm 2 from week 0 to week six. The relative ulcer area showed a significant decrease from 100% to 33%. For patients who experienced ulcer pain (11 patients), its intensity decreased over the six weeks. Severe maceration was not reported for any patient throughout the study. Six patients required treatment for infection. A total of 12 adverse events were reported: seven mild to moderate and five severe. None were directly attributed to the study dressing.