This study aimed to investigate (a) motor planning difficulty by using a two-step test in Parkinson’s disease (PD) compared with age-matched healthy subjects and (b) the relationship between motor planning difficulty and clinical factors. The two-step test was performed by 58 patients with PD with Hoehn & Yahr (H&Y) stage I–IV and 110 age-matched healthy older adult controls. In the two-step test, the participants estimated the two-step distance with maximum effort. Subsequently, they performed the actual two-step trial to measure the actual maximum distance. We calculated the accuracy of the estimation (estimated distance minus actual distance). In both groups, subjects who estimated >5 cm were defined as the overestimation group, and those who estimated <5 cm over- and underestimation were defined as the non-overestimation group. The overestimation group consisted of 17 healthy older adults (15.5%) and 23 patients with PD (39.7%). The number of patients with PD with overestimation was significantly more than that of healthy controls by Chi-squared test. H&Y stage and the Unified Parkinson’s Disease Rating Scale (UPDRS) part II and III scores in overestimation group in PD patients were significantly higher than those in overestimation group in PD patients. Moreover, multiple regression using H&Y stage and UPDRS parts II and III as independent variables showed that the UPDRS part II score was the only related factor for the estimation error distance. Estimation error distance was significant correlated with UPDRS parts II and III. Patients with PD easily have higher rates of motor-related overestimation than age-matched healthy controls. In addition, UPDRS parts II and III expressed ability of activities of daily living and motor function as influences on motor-related overestimation. Particularly, multiple regression indicated that UPDRS part II directly showed the ability of daily living as an essential factor for overestimation.

Since current studies indicate the possible involvement of Chlamydia pneumoniae in the pathogenesis of multiple sclerosis (MS), demonstration of C. pneumoniae in the cerebrospinal fluid (CSF) of patients with MS is highly desirable. However, there is controversy concerning the detection of C. pneumoniae in CSFs from MS patients due to the lack of a standard protocol for extraction and detection of C. pneumoniae DNA. In this regard, we attempted to establish a highly effective extraction protocol for C. pneumoniae DNA from CSFs utilizing a commercial kit and a PCR detection method. The extraction and PCR detection protocol established in this study succeeded in detecting as few as 20 C. pneumoniae organisms in 200 l of mock CSF. The use of this protocol to detect C. pneumoniae DNA in CSFs revealed that 68% of CSF samples obtained from patients with MS were positive (11 out of 16 samples) for chlamydia DNA. Thus, the protocol established here is sensitive enough to detect chlamydia DNA from CSFs and can be used by other laboratories for evaluation of the presence of chlamydiae in CSFs because the protocol is based on the use of a commercial kit.Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS) characterized by focal areas of demyelination. Although the exact etiology of MS is unknown, it is generally accepted that autoimmunity is involved and that the autoantigen(s) probably resides in CNS myelin, the target of the immune response (1). In this regard, current studies argue for an infectious agent as an initiating or enhancing factor for MS with immunological mechanisms (5). To identify a specific causative agent for MS, many groups have attempted to detect microbes in cerebrospinal fluid (CSF) as well as in CNS lesions obtained from MS patients. However, no consistent results have been obtained with any given pathogen. Recent studies conducted by Sriram et al. (12) highlighted the possible involvement of a bacterium in MS, with the finding of Chlamydia pneumoniae in the CSF of almost all patients with MS but in only a small proportion of CSF samples from control subjects without MS. That study has shown the highest association of any organism with MS to date. However, other research groups either could not detect C. pneumoniae in CSFs from MS patients or detected it only in a small proportion of specimens (2,8,14). This may be due to the lack of a standard method for C. pneumoniae detection in CSFs. For study of the involvement of C. pneumoniae in the pathogenesis of MS, a reliable standard evaluation protocol for C. pneumoniae in clinical specimens is essential. Therefore, in the present study, we attempted to establish an efficient extraction protocol for C. pneumoniae DNA in CSFs by use of a commercial kit followed by PCR specific for C. pneumoniae. Furthermore, the extraction and detection system established for C. pneumoniae DNA was applied to demonstration of the presence of C. pneumoniae in CSFs obtained from patients with MS. The results indicate that the proto...

During prolonged, static carotid baroreceptor stimulation by neck suction (NS) in seated humans, heart rate (HR) decreases acutely and thereafter gradually increases. This increase has been explained by carotid baroreceptor adaptation and/or buffering by aortic reflexes. During a posture change from seated to supine (Sup) with similar carotid stimulation, however, the decrease in HR is sustained. To investigate whether this discrepancy is caused by changes in central blood volume, we compared (n = 10 subjects) the effects of 10 min of seated NS (adjusted to simulate carotid stimulation of a posture change), a posture change from seated to Sup, and the same posture change with left atrial (LA) diameter maintained unchanged by lower body negative pressure (Sup + LBNP). During Sup, the prompt decreases in HR and mean arterial pressure (MAP) were sustained. HR decreased similarly within 30 s of NS (65 +/- 2 to 59 +/- 2 beats/min) and Sup + LBNP (65 +/- 2 to 58 +/- 2 beats/min) and thereafter gradually increased to values of seated. MAP decreased similarly within 5 min during Sup + LBNP and NS (by 7 +/- 1 to 9 +/- 1 mmHg) and thereafter tended to increase toward values of seated subjects. Arterial pulse pressure was increased the most by Sup, less so by Sup + LBNP, and was unchanged by NS. LA diameter was only increased by Sup. In conclusion, static carotid baroreceptor stimulation per se causes the acute (<30 s) decrease in HR during a posture change from seated to Sup, whereas the central volume expansion (increased LA diameter and/or arterial pulse pressure) is pivotal to sustain this decrease. Thus the effects of central volume expansion override adaptation of the carotid baroreceptors and/or buffering of aortic reflexes.

This paper is devoted to the analysis of some uniqueness properties of a classical reaction-diffusion equation of the Fisher-KPP type, coming from population dynamics in heterogeneous environments. We work in a one-dimensional interval (a, b) and we assume a nonlinear term of the form u (µ(x) − γ u) where µ belongs to a fixed subset of C 0 ([a, b]). We prove that the knowledge of u at t = 0 and of u, u x at a single point x 0 and for small times t ∈ (0, ε) is sufficient to completely determine the couple (u(t, x), µ(x)) provided γ is known. Additionally, if u xx (t, x 0 ) is also measured for t ∈ (0, ε), the triplet (u(t, x), µ(x), γ ) is also completely determined. Those analytical results are completed with numerical simulations which show that, in practice, measurements of u and u x at a single point x 0 (and for t ∈ (0, ε)) are sufficient to obtain a good approximation of the coefficient µ(x). These numerical simulations also show that the measurement of the derivative u x is essential in order to accurately determine µ(x).Mathematics Subject Classification: 35K20, 35K40, 35K55, 35K57, 35Q80