Model-based cueing-as-needed for walking in Parkinson's disease: A randomized cross-over study.

BACKGROUND: Correcting of the lack of regularity in steps is a key component of gait rehabilitation in Parkinson's disease. We proposed to introduce adaptive spatial auditory cueing (ASAC) based on verbal instruction "lengthen the step" automatically delivered when the stride length decreased below a predetermined threshold. OBJECTIVES: The present study compared the effect of usual rhythmic auditory cueing versus ASAC used during a walking training in Parkinson's disease. METHODS: Fifteen patients with Parkinson's disease performed both interventions in randomized order, one week apart: a 20-minute walking training with rhythmic auditory cueing, in form of a metronome adjusted on 110% of the patient's own cadence, or ASAC delivered when the stride length is less than 110% of the patient's own stride length. Assessment criteria were walking distance covered during the intervention, speed, step length, cadence, coefficients of variation of step length and step duration, and indexes of spatial and temporal asymmetry during a walking test before and just after the intervention. RESULTS: The walking distance is higher with ASAC compared with rhythmic auditory cueing (rhythmic auditory cueing, 905 (203) m, mean (standard deviation); ASAC, 1043 (212) m; P=0.002). Between-intervention comparison showed some similar effects on walking after the intervention including free speed and step length increases (P<0.05). CONCLUSION: The distance covered during 20-minute walking with ASAC increases by 15% compared to the use of classical rhythmic auditory cueing, while the immediate therapeutic effects show similar spatial-temporal benefits on short-distance walking. Auditory biofeedback cueing promoting the increase in step length might improve gait relearning in Parkinson's disease.

Modification of knee flexion during walking with use of a real-time personalized avatar.

Visual feedback is used in different research areas, including clinical science and neuroscience. In this study, we investigated the influence of the visualization of a real-time personalized avatar on gait parameters, focusing on knee flexion during the swing phase. We also studied the impact of the modification of avatar's knee amplitude on kinematic of the knee of healthy subjects. For this purpose, we used an immersive reality treadmill equipment and developed a 3D avatar, with instantly modifiable parameters for knee flexion and extension (acceleration or deceleration). Fourteen healthy young adults, equipped with motion capture markers, were asked to walk at a self-selected pace on the treadmill. A real-time 3D image of their lower limbs was modelized and projected on the screen ahead of them, as if in a walking motion from left to right. The subjects were instructed to continue walking. When we initiated an increase in the knee flexion of the avatar, we observed a similar increase in the subjects' knee flexion. No significant results were observed when the modification involved a decrease in knee flexion. The results and their significance are discussed using theories encompassing empathy, sympathy and sensory re-calibration. The prospect of using this type of modified avatar for stroke rehabilitation is discussed.

Does hip joint positioning affect maximal voluntary contraction in the gluteus maximus, gluteus medius, tensor fasciae latae and sartorius muscles?

BACKGROUND: Minimally invasive total hip arthroplasty (THA) is presumed to provide functional and clinical benefits, whereas in fact the literature reveals that gait and posturographic parameters following THA do not recover values found in the general population. There is a significant disturbance of postural sway in THA patients, regardless of the surgical approach, although with some differences between approaches compared to controls: the anterior and anterolateral minimally invasive approaches seem to be more disruptive of postural parameters than the posterior approach. Electromyographic (EMG) study of the hip muscles involved in surgery [gluteus maximus (GMax), gluteus medius (GMed), tensor fasciae latae (TFL), and sartorius (S)] could shed light, the relevant literature involves discordant methodologies. We developed a methodology to assess EMG activity during maximal voluntary contraction (MVC) of the GMax, GMed, TFL and sartorius muscles as a reference for normalization. A prospective study aimed to assess whether hip joint positioning and the learning curve on an MVC test affect the EMG signal during a maximal voluntary contraction. HYPOTHESIS: Hip positioning and the learning curve on an MVC test affect EMG signal during MVC of GMax, GMed, TFL and S. METHODS: Thirty young asymptomatic subjects participated in the study. Each performed 8 hip muscle MVCs in various joint positions recorded with surface EMG sensors. Each MVC was performed 3 times in 1 week, with the same schedule every day, controlling for activity levels in the preceding 24h. EMG activity during MVC was expressed as a ratio of EMG activity during unipedal stance. Non-parametric tests were applied. RESULTS: Statistical analysis showed no difference according to hip position for abductors or flexors in assessing EMG signal during MVC over the 3 sessions. Hip abductors showed no difference between abduction in lateral decubitus with hip straight versus hip flexed: GMax (19.8±13.7 vs. 14.5±7.8, P=0.78), GMed (13.4±9.0 vs. 9.9±6.6, P=0.21) and TFL (69.5±61.7 vs. 65.9±51.3, P=0.50). Flexors showed no difference between hip flexion/abduction/lateral rotation performed in supine or sitting position: TFL (70.6±45.9 vs. 61.6±45.8, P=0.22) and S (101.1±67.9 vs. 72.6±44.6, P=0.21). The most effective tests to assess EMG signal during MVC were for the hip abductors: hip abduction performed in lateral decubitus (36.7% for GMax, 76.7% for GMed), and for hip flexors: hip flexion/abduction/lateral rotation performed in supine decubitus (50% for TFL, 76.7% for S). DISCUSSION: The study hypothesis was not confirmed, since hip joint positioning and the learning curve on an MVC test did not affect EMG signal during MVC of GMax, GMed, TFL and S muscles. Therefore, a single session and one specific test is enough to assess MVC in hip abductors (abduction in lateral decubitus) and flexors (hip flexion/abduction/lateral rotation in supine position). This method could be applied to assess muscle function after THA, and particularly to compare different approaches. LEVEL OF EVIDENCE: III, case-matched study.

The use of a selective axillary nerve block for outpatient hand surgery.

UNLABELLED: Although no guidelines concerning discharge criteria after axillary plexus block are available, many institutions consider recovery of motor function as a critical factor. With the midhumeral approach, the four main nerves of the upper extremity can be blocked separately using a peripheral nerve stimulator. The aim of this double-blind study was to block the radial (R) and musculocutaneous (MC) nerves with lidocaine, and the median (M) and ulnar (U) nerves with bupivacaine to recover motor function of the elbow and wrist more rapidly while maintaining long-lasting postoperative analgesia at the operative site. Patients undergoing surgery for Dupuytren's contracture were randomized into two groups in a double-blind fashion: in the control group (n = 17), each of the four nerves was infiltrated with 10 mL of a mixture of 2% lidocaine and 0.5% bupivacaine, whereas in the selective group (n = 17), the R and MC nerves were blocked with 10 mL of 2% lidocaine each and the M and U nerves were blocked with 10 mL of 0.5% bupivacaine each. Recovery of motor block was significantly faster in the selective group (231 +/- 91 vs 466 +/- 154 min). However, time to first sensation of pain was not different between groups (707 +/- 274 vs 706 +/- 291 min). In conclusion, this new approach at the midhumeral level enables the anesthesiologist to selectively administer local anesthetics on different nerves. IMPLICATIONS: In outpatients undergoing surgery for Dupuytren's contracture, a midhumeral block was used with the musculocutaneous and radial nerves blocked by lidocaine and the median and ulnar nerves blocked with bupivacaine. Recovery of motor function and time to discharge were shorter compared with patients who received the mixture on all four nerves.

Role of iron in the pathogenesis of Mycobacterium avium infection in mice.

Mycobacterial infections are of serious concern to HIV-infected patients, and take a heavy toll of such patients. Mycobacterium avium is the most common opportunistic bacterial infection in patients with AIDS. The overload of iron in serum has been implicated in the pathogenicity of a number of bacterial infections. Since iron storage in cells such as macrophages is increased in AIDS, the role of iron as a possible factor in the pathogenesis of M. avium infection was examined. Supplementing iron to normal laboratory chow resulted in accelerated M. avium infection in mice inoculated earlier with the same organism. The bacterial loads in liver, spleen and lungs were approximately 12-fold higher in mice receiving iron supplementation compared with control groups. This is attributed to an increased percentage saturation of iron in the sera of the mice, thus making more iron available for the replication of bacteria. The addition of beef fat to the diet, together with high iron supplementation, further enhanced the infection. Using smaller inocula, mice receiving chow supplemented with high iron and fat developed disseminated M. avium infection faster than control mice. The results provide strong evidence that iron may play a major role in the pathogenesis of M. avium infection.

Evaluation of drug interaction microcomputer software: an updated comparison.

Nine drug interaction microcomputer software programs were evaluated and compared using clinical and general ease of use criteria. Descriptions of major changes or additions since the last review are detailed. The ability to screen for drug interactions was based on recent drug-drug and drug-food interactions. Recommended programs based on three price ranges are suggested.

Clinical and ethical perspectives on rationing of high-cost drugs.

OBJECTIVE: To analyze the use of high-cost drugs from a clinical decision-making approach and ethical perspectives on rationing. CASE: The case of a 26-year-old intravenous drug user with AIDS raises issues of how to ration high-cost drugs such as foscarnet, monoclonal antibodies (MAbs) for septic shock, and granulocyte colony-stimulating factor. ASSESSMENT: Should a patient with a terminal illness receive high-cost drugs given limited healthcare resources? Necessary clinical information including treatment algorithms, risk to benefit ratios, and cost-effectiveness data are evaluated. Rationing, especially bedside rationing, by the clinician is rejected because it is contrary to the clinician's ethical obligation of beneficence and nonmaleficence. Patient autonomy and desires may also conflict with society's interest in equitably distributing resources. Treatment could be denied if costs exceed benefits for the outcomes and thus deny resources to others who have more basic healthcare needs. There is no obligation to offer medically futile care or for the patient to accept extraordinary medical care. CONCLUSIONS: An ethical argument for rationing cannot be made because of the lack of a clear clinical and societal consensus on specific criteria for rationing of healthcare dollars. The decision to use high-cost drugs in the case presented is made using a clinical decision-making approach based on available treatment guidelines. This assumes that the patient continues to consent to therapy and that there is continued benefit.

[Nosocomial Aeromonas hydrophila pneumonia complicating toxic coma]. / Pneumopathie nosocomiale à Aeromonas hydrophila compliquant un coma toxique.

A 24-year-old male homosexual drug addict was admitted in coma and circulatory failure after a 10 g overdose of acebutolol. The usual resuscitative measures were undertaken, together with administration of adrenaline and gastric lavage. Six hours of external cardiac massage and pacing, and high catecholamine doses (36 mg.h-1 of adrenaline and 60 micrograms.kg-1 x min-1 of dobutamine) were required before the circulatory system became again spontaneously efficient. After this acute episode, the patient improved despite acute tubular necrosis. On the third day, bilateral alveolar and interstitial lesions were found on the chest film. Bronchoalveolar lavage and protected distal brushings were carried out. Both Aeromonas hydrophila and Staphylococcus aureus were found in the cultured brushings. Treatment with ceftriaxone, vancomycin and amikacin was introduced. This nosocomial pneumonia was very haemorrhagic, resulting in several bloody casts responsible for several episodes of atelectasis. The patient was definitely extubated on the 18th day, and left the ICU 23 days later without any sequela. His HIV status was negative. Four other infections with the same strain of Aeromonas hydrophila occurred at the same time as this patient's. The common source for this germ was found to be soft water. Several measures have since been undertaken: removal of a centralized water softener, filtration and higher chlorine content in the water circuit, and updating of intensive care protocols for disinfection of equipment.

A 28-kilodalton fibronectin-binding protein of group A streptococci.

Lipoteichoic acid (LTA) has been implicated as a major adhesin of group A streptococci that interacts with fibronectin (Fn). It has been suggested that protein adhesins may also be involved in the binding of Fn to streptococci. We searched for such a protein by transblotting membrane preparations from M types 5, 19, and 24 group A streptococci to nitrocellulose and reacting the blot with 125I-Fn. The Fn reacted with a 28-kDa polypeptide from all three serotypes of streptococci. Using affinity-purified antibodies to the 28-kDa protein in immunoblots of membrane preparations from various streptococci, we demonstrated that the 28-kDa protein is present in all 17 strains tested. Affinity-purified antibodies to the 28-kDa protein also reacted in varying degrees with intact streptococci, demonstrating that the antigen is exposed on the surface of intact organisms. Our results suggest that, in addition to LTA, group A streptococci contain a common Fn-binding moiety that is expressed as a major component of membrane preparations and that is accessible on the surface of streptococci for interactions with Fn.

Survey of clinical pharmacokinetic software for microcomputers.

Twelve distributors of pharmacokinetic software programs for microcomputers were surveyed to determine scope of drug coverage; the pharmacokinetics models, methods, and equations used; hardware requirements including use of math coprocessor, random access memory (RAM) required, storage space, printer support and mouse use; software features including availability of windows, pull-down menus, context sensitive help, graphical representation of data, ability to export data including to ASCII file and ability to store patient data; availability of support including toll-free telephone numbers, 24-hour support and clinical consultations; costs; and frequency of updates.

Evaluation of patient counseling microcomputer software programs.

Five patient counseling drug information programs are evaluated using specific criteria definitions. This article compares the features and ratings of each program. The scope of drug coverage is found to be good to excellent. Most of the programs fared poorly in the timeliness of the database. Updates to the programs range from quarterly to undefined schedule. The ease of readability of all the programs is excellent. The inclusion of key components of information is determined to be good to excellent. The overall patient performance ratings are excellent for each of the programs. The programs are all competitively priced. All of the programs evaluated are easy to use. The only distinguishing feature among the programs is the format of the printed output.

Drug interaction microcomputer software evaluation: drug interaction facts on disk.

Drug Interaction Facts on Disk (DIF) was evaluated using general and specific criteria. The installation process, ease of learning and use, the user documentation, and the technical support were rated excellent. The scope of coverage, the quality of the clinical documentation, and overall clinical performance were also excellent. The frequency of updates is good. The program's clinical performance was compared to RxTriage and Drug Therapy Screening System using five recently reported drug interactions. The ability to screen for selected drug-food/nutrient interactions was also evaluated. Drug Interaction Facts is rated to be one of the better bargains in drug interaction software programs.

[The effect of a combination of propofol and fentanyl on cerebral blood flow. A study using transcranial doppler]. / Effet de l'association propofol-fentanyl sur les flux sanguins cérébraux. Etude par doppler transcrânien.

The results of the association propofol fentanyl on the velocity of the middle cerebral artery were studied by means of a transcranial doppler on twenty ASA I patients without any intracranial pathology. Anaesthesia induction by propofol (2.5 mg.kg-1) and fentanyl (2 micrograms.kg-1) induced a significant fall of average velocities (p: 0.0001) and an increase of the resistance index (p: 0.0001) without any associated variation of mean blood pressure and CO2 expiratory fraction. These results corroborate the variations of cerebral blood flow and cerebral vascular resistances reported in the literature and give evidence, in all probability, of a cerebral autoregulation phenomenon.

Evaluation of IV compatibility microcomputer software programs.

Four microcomputer software programs that contain IV compatibility information were evaluated using specific criteria for these programs. This article compares scope of coverage, quality of clinical documentation, frequency updates, and clinical performance for these programs. There are no excellent IV compatibility programs. Of the programs tested, Micromedex performed the best. Therapeutic Software is not considered a comprehensive IV compatibility program. IV-Check PC and Medicom Micro performed equally well.