CSF monoamine metabolite levels in Alzheimer's and Parkinson's disease

Levels of the monoamine metabolites homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) were measured in lumbar CSF from 32 patients with a clinical diagnosis of Alzheimer's disease (AD) and from 21 patients with Parkinson's disease (PD). The baseline CSF metabolite values did not differ significantly between the two groups of patients, although HVA levels were lowest in patients with PD and in the more severely demented patients with AD. Levels of all three metabolites increased significantly in both patient groups during probenecid administration, but HVA levels were significantly higher in patients with AD than in patients with PD. Within the AD group, those with the most severe dementia had the greatest rise in MHPG levels. Alterations in monoamine metabolite levels in the CSF detected during probenecid administration aid in the differential diagnosis of neurodegenerative diseases such as AD.     

Prognostic Factors in Myeloma: What They Tell Us About the Pathophysiology of the Disease

Prognostic factors in myeloma are not only important for allowing comparisons to be made between therapeutic protocols but they also provide us with an insight into the pathophysiology of the disease and important mechanisms which result in disease progression. Prognostic factors in myeloma relate to the inherent proliferative capacity of the malignant clone, tumor bulk, renal function and other factors which reflect tumor host and host tumor interactions. The highly significant effect of the labelling index (LI) suggests that the clonogenic cell is ontologically very close to the malignant plasma cell on which the labelling index is derived. The explanation for the important role of the β2-microglobulin (β2M) level over and above its reflection of renal function is as yet unclear.     

Selective projections from the cat red nucleus to digit motor neurons

Classical studies of the cat rubrospinal tract describe dense terminations in spinal laminae V-VII and an absence of any significant projection to lamina IX. In contrast, our recent studies, utilizing the anterograde transport of wheat germ agglutinin conjugated with horseradish peroxidase, have demonstrated a consistent and circumscribed area of label in lamina IX at caudal cervical segments. The present study was undertaken to determine the distribution of rubrospinal terminals among motor neurons in lamina IX as well as to identify the likely target muscles of those motor neurons located near rubrospinal terminals. We injected wheat germ agglutinin-horseradish peroxidase into the red nucleus and unconjugated horseradish peroxidase into selected forearm muscles of the same side of the body. The locations of rubrospinal terminals showing anterograde label on one side of the spinal cord could then be compared with the locations of motor neurons showing retrograde label on the opposite side of the cord. The results demonstrated a clear focus of rubrospinal terminals in the lateral and dorsal portions of the ventral horn beginning at C8 and extending through rostral T1. No other segments of the spinal cord showed a focus of rubrospinal terminations in lamina IX. Retrogradely labeled motor neurons from the muscle injections showed that the rubrospinal terminals overlap extensively with motor neuronal pools supplying distal forearm muscles. Several lines of evidence indicate that the terminals are from rubrospinal fibers and are not due to transneuronal transport.     

Children conceived using ICSI do not have an increased risk of delayed mental development at 5 years of age

BACKGROUND: Concerns about possible adverse outcomes for children conceived using ICSI were highlighted in 1998 when 1-year-old ICSI children were found to be at increased risk (relative risk = 9.2) of delayed mental development compared with children conceived naturally or using IVF. As the findings were biologically plausible, it was considered important to reassess child development when a more accurate measure of long-term cognitive ability could be obtained. METHODS: The mental development of 97 ICSI, 80 IVF and 110 naturally conceived (NC) children at 5 years of age was assessed using intelligence quotients (IQ) obtained from the Wechsler Preschool and Primary Scales of Intelligence. RESULTS: The mean full-scale IQ was 110 +/- 18 for ICSI, 111 +/- 13 for IVF and 114 +/- 13 for NC children (P = 0.21, non-significant). ICSI children were not at increased risk for delayed (full-scale IQ <85) cognitive development (ICSI 5.2%, IVF 2.5%, NC 0.9%; P = 0.18, non-significant). The only significant independent predictor of below-average full-scale IQ on multivariate analysis was lower maternal education level. CONCLUSIONS: These findings suggest that the genetic influence of parental cognitive ability is more important than the mode of conception in determining the long-term intellectual ability of children conceived using ICSI.     

Snoring, daytime sleepiness and stroke: a case-control study of first-ever stroke

Previous reports have shown an association between snoring and stroke but it is not clear whether this reflects confounding factors nor whether the association is attributable to obstructive sleep apnoea (OSA). We performed a case-control study of 181 patients admitted to hospital with first-ever stroke and community control subjects matched individually for age, sex and general practitioner. Subjects were interviewed with a structured questionnaire to identify snoring, daytime sleepiness and stroke risk factors. The association between snoring alone and stroke was not statistically significant: odds ratio (95% CI) 1.44 (0.88, 2.41). Daytime sleepiness was, however, significantly associated with stroke: odds ratio 3.07 (1.65, 6.08). Multiple logistic regression showed that hypertension, current smoking, taking alcohol regularly (negatively) and a higher Epworth sleepiness score were independently associated with stroke. The results suggest that the previously reported association between 'simple' snoring and stroke might have been due to poor controlling for confounding variables. Our study suggests an association with greater sleepiness prestroke, the cause of which is unclear, although OSA is a possible candidate.     

Blood Pressure Measurement for Hypertension in Pregnancy

ObjectiveAmbulatory BP monitoring (ABPM) has been proposed as a logical approach to overcoming many of the problems associated with clinical BP measurement. The extent of its use in diagnosing hypertension in pregnancy is unknown. The objective of this study was to identify the practices surrounding use of ABPM by practitioners to diagnose hypertension (HTN) and white coat hypertension (WCH) in pregnant women.MethodsWe mailed questionnaires to all obstetricians and family doctors practising obstetrics who were listed in the online medical directory of the College of Physicians and Surgeons of Alberta. Data were analyzed using SPSS.ResultsCompleted questionnaires were received from 81 obstetricians and 86 primary care physicians who manage hypertension in pregnancy. The majority of obstetricians (83%) and primary care physicians (79%) indicated that they “almost always” or “often” attempt to differentiate WCH from true HTN in pregnancy. The most popular method identified to differentiate WCH from true HTN in pregnancy was self (intermittent) home BP monitoring (78% of obstetricians and 69% of primary care physicians, P = 0.18). A minority of physicians in each group reported using ABPM to evaluate HTN in pregnancy, with significantly fewer obstetricians using ABPM diagnostically than primary care physicians (12% vs. 26%, P = 0.04).ConclusionObstetrical care providers in Alberta are aware that WCH is an issue among pregnant women. While ABPM is chosen in a minority of cases, both obstetricians and primary care physicians appear to have a strong preference to use self BP monitoring for further BP evaluation.     

Structure and expression of the gene for Pv200, a major blood-stage surface antigen of Plasmodium vivax.

Molecular cloning and structure analysis of the gene encoding the Pv200 protein of the Sal-1 strain of Plasmodium vivax revealed an overall identity of 34–37% when the deduced amino acid sequence was compared with the sequences of various major merozoite surface antigens of Plasmodium falciparum, Plasmodium yoelii and Plasmodium chabaudi. When the Sal-1 Pv200 sequence was compared with the corresponding sequence from the Belèm strain of P. vivax, it was found that the two merozoite surface antigens were relatively well conserved with an overall amino acid sequence identity of 81%. A region of 23 repeated glutamine residues, found in the sequence of the Belèm isolate was not found, however, in the Sal-1 sequence. Amino-and carboxy-terminal domains of the Pv200 protein were expressed in the yeast Saccharomyces cerevisiae. Each recombinant protein was shown to react with antibodies in sera from splenectomized Bolivian Saimiri monkeys that had been infected previously with P. vivax, and in human sera from individuals with a history of exposure to vivax malaria. The availability of recombinant DNA-derived Pv200 proteins will now allow a full assessment of their utility in the diagnosis and immunoprophylaxis of the benign tertian malaria associated with P. vivax infection.