Molecular diagnosis of type 1c glycogen storage disease

Glycogen storage disease type 1 (GSD 1) results from deficiency of the microsomal multicomponent glucose-6-phosphatase system. Malfunction of the catalytic subunit characterises GSD 1a. GSD 1b and GSD 1c are characterised by defective microsomal glucose-6-phosphate or pyrophosphate/phosphate transport, respectively. Recently, a gene encoding a microsomal transporter protein has been found to be mutated in GSD 1b and 1c patients. Here, we report the genomic sequence of the transporter gene and the detection of a homozygous 2-bp deletion (1211delCT) and a homozygous donor splice site mutation (317+1G→T) in two GSD 1c patients, confirming that GSD 1c is allelic to GSD 1b. Received: 16 October 1998 / Accepted: 11 January 1998     

Presenting joint kinematics of human locomotion using phase plane portraits and Poincaré maps

Additional graphical tools are needed to better visualize the joint kinematics of human locomotion. Standard plots in which the joint displacements are plotted against time or percent gait cycle do not provide sufficient information about the dynamics of the system. In this article, a study based on the two graphical tools of nonlinear dynamics to visualize the steady-state kinematics of human gait is presented. An experimental setup was developed to acquire the necessary data for application of the techniques. Twenty young adults, whose medical histories are free of gait pathology, were tested. Computerized electrogoniometers and foot switches were used to measure the kinematic data of the lower extremities and capture four instants of the gait cycle: heel strike, foot flat, heel off, and toe off. Phase plane portraits of each joint were constructed for the sagittal plane by plotting angular velocity against angular displacement. Poincaré maps were obtained by periodically sampling the joint profiles at toe off and plotting the ith iterate against the (i + 1)th one. Phase plane portraits are useful in monitoring the variations of joint velocity and position on the same graph in a more compact form. Poincaré maps are effective in differentiating steady gait from transient locomotion.     

Novel dichloromethane-fermenting bacteria in the Peptococcaceae family

Dichloromethane (DCM; CH₂Cl₂) is a toxic groundwater pollutant that also has a detrimental effect on atmospheric ozone levels. As a dense non-aqueous phase liquid, DCM migrates vertically through groundwater to low redox zones, yet information on anaerobic microbial DCM transformation remains scarce due to a lack of cultured organisms. We report here the characterisation of DCMF, the dominant organism in an anaerobic enrichment culture (DFE) capable of fermenting DCM to the environmentally benign product acetate. Stable carbon isotope experiments demonstrated that the organism assimilated carbon from DCM and bicarbonate via the Wood–Ljungdahl pathway. DCMF is the first anaerobic DCM-degrading population also shown to metabolise non-chlorinated substrates. It appears to be a methylotroph utilising the Wood–Ljungdahl pathway for metabolism of methyl groups from methanol, choline, and glycine betaine. The flux of these substrates from subsurface environments may either directly (DCM, methanol) or indirectly (choline, glycine betaine) affect the climate. Community profiling and cultivation of cohabiting taxa in culture DFE without DCMF suggest that DCMF is the sole organism in this culture responsible for substrate metabolism, while the cohabitants persist via necromass recycling. Genomic and physiological evidence support placement of DCMF in a novel genus within the Peptococcaceae family, ‘Candidatus Formimonas warabiya’.Subject terms: Pollution remediation, Microbial ecology, Soil microbiology, Biogeochemistry     

Quantification the relationship between FITA scores and EMG skill indexes in archery.

Forearm electromyographic (EMG) data are assumed to be an effective method in estimating performance level in archery. The aim of the current study was to establish archery skill indexes based on EMG data. Elite (n=7, FITA score=1303.4+/-26.2), beginner (n=6, FITA score=1152+/-9.0) and non-archers (n=10, assumed FITA score=250+/-0), were involved in the study. EMG activity of Muscle flexor digitorum superficialis and Muscle extensor digitorum were quantified. Two-second periods--1 s before and 1 s after the fall of the clicker--were used to obtain averaged and rectified EMG data. The averaged and rectified EMG data were filtered by averaging finite impulse response filter with 40 ms time window and then normalized with respect to maximum voluntary contraction. To estimate FITA scores from EMG data, the following skill indexes that based on mean area under some parts of processed EMG waveforms was offered for archery. These were the pre-clicker archery skill index (PreCASI), post-clicker archery skill index (PostCASI), archery skill index (ASI) and post-clicker archery skill index 2 (PostCASI2).The correlations between rank of FITA scores and natural logarithms of archery skill indexes were significant for log(PreCASI): r=-0.66, p<0.0008; for log(PostCASI): r=-0.70, p<0.0003; for log(ASI): r=-0.74, p<0.0001; log(PostCASI2): r=-0.63, p<0.002. It is concluded that EMG skill indexes may be useful for: (a) assessing shooting techniques, (b) evaluation of archers' progress and (c) selection of talented archers.