Long polymerase chain reaction-based fluorescence in situ hybridization analysis of female carriers of X-linked chronic granulomatous disease deletions

Chronic granulomatous disease (CGD) is a rare inherited disorder in which antimicrobial activity of phagocytes is impaired due to the lack of reactive oxygen species, or oxidative burst, produced by NADPH oxidase. The X-linked form of CGD, representing approximately 70% of all cases, is caused by mutations in the cytochrome b beta subunit (CYBB) gene, which maps to chromosome Xp21.1. CYBB encodes the gp91-phox protein, a necessary component in the NADPH oxidase pathway. A wide variety of mutations have been identified in X-linked CGD patients, all of which lead to deletion of the functional protein and no oxidative burst activity. The mutations vary from single nucleotide substitutions to deletions of the entire gene. In this article, we report a mutation detection method for probands of female relatives at risk for carrier status of large deletions of the CYBB gene. Through fluorescent in situ hybridization of metaphase chromosomes, we were able to consistently distinguish carriers from noncarriers using polymerase chain reaction-derived, labeled DNA specific for exons 2 to 13 of the CYBB region at Xp21.1.     

Cold caloric microcirculatory reflex disturbance in patients with Parkinson's disease

The basal skin microcirculatory blood flow and its change in response to a cold caloric stimulus (cold water, 5°C, exposure of one foot for 30 s) were investigated in nine patients with Parkinson's disease (PD) and nine normal subjects (controls). The results revealed a significant (p<0.001) difference between the groups. In the controls there was a strong decrease in the red cell flux (RCF) on cold water exposure, while eight of the nine PD patients revealed no detectable change in RCF; in one patient only there was a less pronounced reaction. It was concluded that the regulation of the microcirculatory blood flow was affected in PD patients; the cold caloric reflec was attenuated or absent but there was no difference in the basal microcirculatory blood flow compared to normal subjects.     

Effects of aging on slowing of motor-response generation.

The aim of the present study was to analyze different stages of central processing mechanisms during a choice reaction task and to evaluate their contribution to aging-related response slowing. Event-related potentials (ERPs) were recorded from two groups of subjects, young (mean 22 years) and older adults (mean 58 years), who performed a four-alternative choice-reaction task. The results showed the expected reaction time slowing in the older subjects. This behavioural slowing was not due to delays in stimulus processing (as reflected by latencies of early ERP components), or in response selection (as reflected by the onset of the lateralized readiness potential). Instead, this slowing was due to an alteration of movement-related components, particularly an amplitude enhancement and prolongation of the motor-related potential at the cortex contralateral to the responding hand. This alteration was reliable and of general nature since it was also found in a second study using a different choice-reaction task with a more direct stimulus-response relation. The results suggest that the overt response requires a higher activation level in older vs. young subjects; this extra-activation needs time and hence prolongs reaction time with aging.     

Streptokinase does not activate the complement system.

Streptokinase is an extensively used thrombolytic agent. However, different preparations cause severe hypotension during therapy, partially related to the complement cascade activation. In four ischaemic stroke patients treated with Streptase, an increased level of soluble terminal complement complex (SC5b-9) was measured. In the sera of normal subjects, the increase in SC5b-9 induced by Streptase, Kabikinase and Calbiochem streptokinases was highly significant (P < 0.005). Sigma streptokinase did not activate the complement system. Sigma streptokinase analyzed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed a homogeneous band. The other three preparations were contaminated with albumin and other proteins. Based on our in vivo and in vitro data, we conclude that complement activation is related to contamination of different streptokinase products rather than the streptokinase itself.     

Concentration of blood lead and ethnicity in the United Kingdom.

The relation between concentration of blood lead and ethnic background in 779 children was examined with the analytical results from the trace element service at the Medical Toxicology Unit (MTU), Guy's and St Thomas's Hospital Trust for the period 1980-94. The ethnic identity was determined with the first and the second names of the investigated subjects. Of the patients of European origin (European) studied 72.8% v only 50.6% of the children with origins in the Indian subcontinent (Asian) had a concentration of blood lead < 100 micrograms/l. The percentage of subgroups with concentrations above the upper acceptable limit of 200 micrograms/l was significantly higher in Asian subjects (European 5% v Asian 26.5%), with the most pronounced difference in those with concentrations of blood lead of 500 micrograms/l (European 0.8% v Asian 10.5%). This study shows that a correlation exists between Asian ethnic background and concentration of blood lead in children. Factors such as cultural habits-for example, use of traditional remedies, cosmetics, diet- and socioeconomic status, may have contributed to this results.