Premenstrual tension,expectancy, and mother-child relations

The role of expectancy in enhancing or mitigating premenstrual symptoms was examined in 51 mothers of preschoolers. Expectancy was manipulated by providing information either in support of a biological cause for genuine universal mood changes or in support of a psychological cause arising out of negative societal myths. A third group was given no information. Mood, cognitive function, and mother-child interaction were assessed both at midcycle and premenstrually, and the results suggested that expectancy enhances symptoms. The Psychological group lowered their symptom expectations and reported less negative mood premenstrually as well as fewer symptoms at the end of the test month. The other groups reported no change in symptoms and greater premenstrual negative mood than the Psychological group. All groups demonstrated greater task persistence and more positive motherchild interaction during the premenstrual phase.This study is based upon the doctoral dissertation completed in partial fulfillment of the Ph.D. degree from the University of Ottawa.     

Hereditary cholinesterase deficiency: A report of a family with two rare genotypes

Cholinesterase deficiency was detected in a young girl following an episode of post-anesthesia apnea. Subsequently, plasma and serum cholinesterase levels and dibucaine numbers were determined on blood samples from 56 members of her extended family. Including the proband, three individuals were identified with severe cholinesterase deficiency and 12 were found to have mild abnormalities. The occurrence of two genetic variants regulating cholinesterase production, the "silent" gene and the atypical enzyme, is postulated to account for the unusual pattern of inheritance in this family. Screening family members of confirmed cases is essential to prevent the potentially fatal consequences of this hereditary disorder.     

Receptor for the C3a anaphylatoxin is expressed by neurons and glial cells

Little is known about the expression of the receptor for complement anaphylatoxin C3a (C3aR) in the central nervous system (CNS). In this study, we provide the first evidence that neurons are the predominant cell type expressing C3aR in the normal CNS. By using in situ hybridization (ISH) and immunohistochemistry, we found that C3aR is constitutively expressed at high levels in cortical and hippocampal neurons as well as in Purkinje cells. Moreover, we showed that primary culture of human astrocytes and microglia express the C3aR mRNA as assessed by RT‐PCR. In situ hybridization performed on rat primary astrocytes confirmed the RT‐PCR result demonstrating C3aR expression by astrocytes. In experimental allergic encephalitis (EAE), C3aR expression was elevated on microglia, infiltrating monocyte‐macrophage cells and a few astrocytes, whereas neuronal expression remained unchanged during the course of the disease. These data demonstrate that the C3aR is expressed primarily by neurons in the normal CNS and that its neuronal expression is not dramatically upregulated under inflammation. This is in contrast to the increased neuronal expression of the C5aR in several inflammatory CNS conditions. The high constitutive expression of the C3aR by neurons suggests this receptor may play an important role in normal physiological conditions in the CNS. GLIA 26:201–211, 1999. © 1999 Wiley‐Liss, Inc.     

A projection from the entorhinal cortex to the nucleus accumbens in the rat

A study was performed in which both anterograde ([³H]leucine radioautography) and retrograde (horseradish peroxidase (HRP) histochemistry) tracing methods were employed to identify the origin of the fimbrial projection to the nucleus accumbens in the rat. The data reveal that this pathway arises predominantly from layers II–III of the anterior two-thirds of entorhinal cortex rather than from any part of hippocampal formation.     

Endovascular Therapy for Ischemic Stroke

The utility of intravenous tissue plasminogen activator (IV t-PA) in improving the clinical outcomes after acute ischemic stroke has been well demonstrated in past clinical trials. Though multiple initial small series of endovascular stroke therapy had shown good outcomes as compared to IV t-PA, a similar beneficial effect had not been translated in multiple randomized clinical trials of endovascular stroke therapy. Over the same time, there have been parallel advances in imaging technology and better understanding and utility of the imaging in therapy of acute stroke. In this review, we will discuss the evolution of endovascular stroke therapy followed by a discussion of the key factors that have to be considered during endovascular stroke therapy and directions for future endovascular stroke trials.     

Evaluation of ultrasound-guided diagnostic local anaesthetic hip joint injection for osteoarthritis

Purpose

The diagnosis of hip osteoarthritis is often complicated by co-existing pathology in the knee and spine, and mismatch between clinical and radiological signs. Temporary pain relief from a local anaesthetic injection into the hip joint has been reported to help localise symptoms, reducing the risk of unnecessary surgery being performed. We hypothesize that good surgical outcome is predicted by good analgesia following diagnostic injection, and that alternative pathology is present when there is no response to injection.

Methods

Data were analysed from a prospective database of 163 consecutive patients who underwent diagnostic hip injection for possible osteoarthritis. We recorded result of injection and whether hip arthroplasty was performed. A good outcome to surgery was defined as subsequent pain relief without significant residual symptoms.

Results

A total of 138 patients were suitable for inclusion in the study. Fifty-eight patients had hip arthroplasty following a good response to diagnostic injection. Of these 54 had a good outcome following surgery (93%). There was also a quantitative improvement in pain and function in these patients as measured by 1?year post-operative and pre-operative Harris hip scores (P?Conclusion Diagnostic ultrasound-guided local anaesthetic injection of the hip joint is a useful test in confirming hip pathology. Complete relief of hip pain following intracapsular injection of local anaesthetic is associated with good surgical outcome following joint replacement.     

Time-dependent involvement of the dorsal hippocampus in trace fear conditioning in mice

Hippocampal and amygdaloid neuroplasticity are important substrates for Pavlovian fear conditioning. The hippocampus has been implicated in trace fear conditioning. However, a systematic investigation of the significance of the trace interval has not yet been performed. Therefore, this study analyzed the time-dependent involvement of N-methyl-D-aspartate (NMDA) receptors in the dorsal hippocampus in one-trial auditory trace fear conditioning in C57BL/6J mice. The NMDA receptor antagonist APV was injected bilaterally into the dorsal hippocampus 15 min before training. Mice were exposed to tone (conditioned stimulus [CS]) and footshock (unconditioned stimulus [US]) in the conditioning context without delay (0 s) or with CS-US (trace) intervals of 1-45 s. Conditioned auditory fear was determined 24 h after training by the assessment of freezing and computerized evaluation of inactivity in a new context; 2 h later, context-dependent memory was tested in the conditioning context. NMDA receptor blockade by APV markedly impaired conditioned auditory fear at trace intervals of 15 s and 30 s, but not at shorter trace intervals. A 45-s trace interval prevented the formation of conditioned tone-dependent fear. Context-dependent memory was always impaired by APV treatment independent of the trace interval. The results indicate that the dorsal hippocampus and its NMDA receptors play an important role in auditory trace fear conditioning at trace intervals of 15-30-s length. In contrast, NMDA receptors in the dorsal hippocampus are unequivocally involved in contextual fear conditioning independent of the trace interval. The results point at a time-dependent role of the dorsal hippocampus in encoding of noncontingent explicit stimuli. Preprocessing of long CS-US contingencies in the hippocampus appears to be important for the final information processing and execution of fear memories through amygdala circuits.