D3 dopamine receptor mRNA expression in lymphocytes: a peripheral marker for schizophrenia?

BACKGROUND

Identification of schizophrenia, a common neuropsychiatric disorder, is based on clinical examination. An easily measurable peripheral marker, which may enable a more rapid and more accurate diagnosis, is not available. A possible candidate is the D3 dopamine receptor on lymphocytes.

OBJECTIVE

The D3 receptor is investigated for its clinical significance as a marker for diagnosing schizophrenia.

METHODS

From eight schizophrenic patients and eight controls lymphocyte RNA was isolated. A semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) was carried out and the intensities of the specific D3 dopamine receptor bands of patients and controls were compared.

RESULTS

No difference could be seen between the intensities of the bands from patients and controls.

CONCLUSION

An aberrant D3 dopamine receptor mRNA expression in lymphocytes of schizophrenics could not be demonstrated. This might be caused by down-regulation of D3 receptor production by antipsychotic drug treatment. At present, the D3 receptor seems to have no diagnostic value in schizophrenia.

History effects and phase diagram near the lower critical point in YBa2Cu3O7 single crystals

Using a sensitive torque magnetometer we have studied magnetization curves for untwinned overdoped YBa2Cu3O7 single crystals in fields of up to 28 T. We demonstrate the existence of history effects below the lower critical point and provide a full demarcation of the Bragg-glass phase. A pronounced symmetry is observed in the behavior of the phase lines, irreversible magnetization, and value of the magnetization jump near both critical points.

Detection of antibodies to Salmonella enteritidis in sera and yolks from experimentally and naturally infected chickens

An indirect enzyme-linked immunosorbent assay (ELISA) based on the lipopolysaccharide (LPS) of Salmonella enteritidis phage type 4, was developed for the detection of antibodies to salmonella. Sera and yolks from chickens infected experimentally with S enteritidis showed strong positive reactions. Cross-reactions occurred with sera from chickens inoculated with S typhimurium or S gallinarum. Cross-reactions were weak with sera from chickens infected with five strains of other Enterobacteriaceae. The ELISA was tested with sera and yolks from commercial poultry flocks which were bacteriologically negative for salmonella or infected with salmonella serotypes belonging to serogroup D or to other serogroups. The serological reactions were strong in most flocks infected with S enteritidis and were weaker in flocks infected with S typhimurium. In some flocks infected with these serotypes no antibodies were detected. The correct setting of the cut-off value of the optical density in the ELISA makes it possible to discriminate between chickens which are infected with S enteritidis and chickens which are not infected with S enteritidis.

[Consensus depression in adults. Dutch Association for Psychiatry]

Depression is a frequent and treatable disorder, but it is insufficiently recognized. A generally used classification system is lacking. In a consensus meeting the following terms were defined: a normal feeling of depression, depression as a symptom and depression as an illness. The use of the term 'masked depression' was advised against. The undertreatment mentioned is caused by the following factors: presentation of physical symptoms by depressive patients, unfamiliarity of patients with depressive disorders and difficulties of patients and GPs in labelling depression as mental. Depressive disorders have various causes. For scoring the severity of depression the Bech version of the Hamilton Depression Rating Scale is preferred. There is no valid laboratory test for diagnosing depression. Laboratory tests are recommended to exclude physical disorders, for choosing an antidepressant and for the follow-up of drug treatment. Cognitive Behavioural Therapy and Interpersonal Therapy are preferred psychotherapeutic methods because of their scientifically proved efficacy. Women suffer from depression twice as frequently as men, which is due to social factors rather than to genetic or hormonal factors. Therefore hormonal therapy is not indicated, a more equal doctor-patient relationship is. Patients with a depressive disorder may consider suicide; this should regularly be discussed with them.

Predicting symptoms of depression from reports of early parenting: a one-year prospective study in a community sample

The purpose of this study was to determine whether (reported) parental over involvement and lack of affection identify initially healthy subjects at risk for depression. One thousand subjects from the province of Utrecht, the Netherlands were randomly selected by using telephone addresses and asked to participate in a one-year prospective study on psychological risk factors of depression. From the 108 subjects that finally participated on both occasions, the reports of parental upbringing (Parental Bonding Instrument) of initially non-depressed subjects with a Zung Self-rating Depression Scale score below 49 points were used to predict new cases of depression one year later. Initially non-depressed subjects who reported maternal over involvement in the upper quartile of the distribution had an 8.5-fold increased risk (95% confidence interval 0.9 to 80.6) of becoming depressed one year later. Although initial reports of low paternal affection were positively associated with initial symptoms of depression, this characteristic failed to show predictive value. Parental upbringing deficiencies have frequently been shown in cross-sectional inpatient studies in which retrospective retrieval from memory because of depressive state characteristics may have caused negative colouring. Our results would suggest that maternal over involvement reported in the absence of a depressed mood still proves to be an important psychological risk factor in the aetiology of depression.

Brain gangliosides in the presenile dementia of Pick

Histochemical analysis of frontal and temporal lobes from four patients with Pick presenile dementia indicated intracellular and extracellular deposits of gangliosides. Thin layer chromatography of gangliosides disclosed the presence of an unknown ganglioside, a decrease of N-acetylgalactosamine-GDla and an increase of GTla and/or GD2 in white matter of Pick brain. Chromatography of gray matter and quantitation of the sialic acid content yielded results similar to controls. It is suggested that degradation and removal of gangliosides is incomplete in Pick disease.