Effects of pro-cholinergic treatment in patients suffering from spatial neglect.

Spatial neglect is a neurological condition characterized by a breakdown of spatial cognition contralateral to hemispheric damage. Deficits in spatial attention toward the contralesional side are considered to be central to this syndrome. Brain lesions typically involve right fronto-parietal cortices mediating attentional functions and subcortical connections in underlying white matter. Convergent findings from neuroimaging and behavioral studies in both animals and humans suggest that the cholinergic system might also be critically implicated in selective attention by modulating cortical function via widespread projections from the basal forebrain. Here we asked whether deficits in spatial attention associated with neglect could partly result from a cholinergic deafferentation of cortical areas subserving attentional functions, and whether such disturbances could be alleviated by pro-cholinergic therapy. We examined the effect of a single-dose transdermal nicotine treatment on spatial neglect in 10 stroke patients in a double-blind placebo-controlled protocol, using a standardized battery of neglect tests. Nicotine-induced systematic improvement on cancellation tasks and facilitated orienting to single visual targets, but had no significant effect on other tests. These results support a global effect of nicotine on attention and arousal, but no effect on other spatial mechanisms impaired in neglect.

Plantar pressure distribution in Type 2 diabetic patients without peripheral neuropathy and peripheral vascular disease.

AIMS: To evaluate the distribution of plantar pressure during walking on a level gradient in patients with Type 2 diabetes mellitus without any microvascular and macrovascular complications and to compare them with non-diabetic control subjects. METHODS: A group of 15 patients with Type 2 diabetes mellitus without either peripheral neuropathy or peripheral vascular disease (PVD), as well as without both diabetic retinopathy and nephropathy, was compared with a group of 15 non-diabetic subjects matched for age, sex, body weight and height. The plantar pressure and duration of plantar pressure were measured on big toe, 1st, 3rd and 5th metatarsal heads, and on the heel of both feet by Force Sensing Resistors sensors. The static contact plantar surface was measured by method of Harris footprints. RESULTS: The diabetic group showed a significant increase in peak plantar pressure at the level of the big toe [right foot 205 +/- 94 vs. 101 +/- 39 kPa (mean +/- SD), P = 0.01; left foot 165 +/- 61 vs. 104 +/- 43 kPa, P = 0.05] and 5th metatarsal head (right foot 160 +/- 68 vs. 97 +/- 32 kPa, P = 0.05; left foot 174 +/- 65 vs. 91 +/- 42 kPa, P = 0.02) with a significantly prolonged duration of plantar pressure at each step. Under the heel, the peak plantar pressure was significantly lower in the diabetic group (right foot 187 +/- 54 vs. 321 +/- 91 kPa, P = 0.05; left foot 184 +/- 63 vs. 298 +/- 110 kPa, P = 0.05). No significant differences were noted under 1st and 3rd metatarsal heads. The contact plantar surface was significantly reduced in the diabetic group compared with control subjects (right foot 118.2 +/- 10.8 vs. 141.5 +/- 12.7 cm2, P = 0.05; left foot 127.5 +/- 8.7 vs. 140.0 +/- 11.1 cm2, P = 0.05). CONCLUSIONS: We observed an anterior displacement of weight-bearing during walking on a level gradient as well as a reduced static contact plantar surface in diabetic patients without evidence of any complications compared with the non-diabetic control group. This could be a premature sign of peripheral neuropathy, which is not evaluated on clinical examination or quantitative sensory testing used in clinics.

Immunogenicity of trivalent subunit versus virosome-formulated influenza vaccines in geriatric patients.

The safety and immunogenicity of a commercial trivalent subunit influenza vaccine and an experimental virosome-formulated influenza vaccine were evaluated among geriatric patients in a double-blind, randomized manner. The virosome vaccine was produced by incorporating hemagglutinin (HA) into the membrane of liposomes composed of phosphatidylcholine. Both vaccines elicited a significant (P < 0.01) rise in the geometric mean anti-HA antibody titer to all three vaccine components 1 month after immunization. However, significantly (P < 0.005) more subjects vaccinated with the virosome preparation mounted a more than fourfold rise to the A/Singapore and A/Beijing strains compared with those who received subunit vaccine. The percentage of patients who attained protective levels (anti-HA titer > or = 40) of anti-A/Beijing antibody was also significantly (P < 0.005) higher in the virosome group. Subjects who possessed non-protective baseline antibody levels to the A/Singapore and A/Beijing strains were more likely (P < 0.005-0.030) to achieve protective levels after immunization with the virosome vaccine than with the subunit vaccine. Of particular clinical significance was the fact that 68.4% of subjects immunized with the virosome vaccine attained protective levels of antibody to all three vaccine components versus 38% for the subunit vaccine (P = 0.010).

Prevalence of infections and their risk factors in geriatric institutions: a one-day multicentre survey.

This one-day prevalence survey of 1919 patients (74% females and 44% aged greater than or equal to 85 years) in nine geriatric hospitals, six of them located in France and three in Switzerland, indicated a high prevalence of infections in elderly institutionalized patients (infection rate: 18.7% in males and 15.4% in females). The risk factors for infection were identified and the relative risks assessed. Prevention of infections in geriatric wards should be one of the goals of every care-giver. A low rate of infection in elderly inpatients is thus likely to be associated with care of good quality.

Accidental bromine exposure in an urban population: an acute epidemiological assessment.

In November 1984, because of an accident at a chemical plant, the population of a large area in the town of Geneva, Switzerland, was exposed to toxic bromine gas during several hours at concentrations above the short-term exposure limit. We describe the development of the disaster, the reactions of the fire brigade, the police and the first aid services as well as the breakdown of communications that occurred. On-the-spot epidemiological assessment of the exposed area and of the characteristics of the exposure syndrome was combined with the emergency care of 91 self-referred patients that were seen at the University Hospital. Follow-up was obtained one month later. The clinical course was moderate (eyes and upper airways irritation) and self-limiting in all cases. Immediate definition of the exposed population permitted effective follow-up. Such early evaluation could prove to be of crucial importance for managing more serious accidents of a similar nature.

[Bromine cloud in Geneva. Epidemiologic study of the short-term effects on a population sample]. / Nuage de brome à Genève. Etude épidémiologique des effets à court terme sur un échantillon de la population.

In November 1984, due to an accident at a chemical plant, toxic bromine gas spread into the town of Geneva, Switzerland, at concentrations over five times the maximal admissible concentration (MAC). Monitoring of atmospheric brome concentrations allowed the determination both of the duration of exposure and the geographical area concerned. Description of the immediate measures taken at the time of the accident illustrates how mass panic reactions can be generated or controlled, and clearly shows the vital importance of an effective communication network: it was lacking in this case and caused further insecurity for the population and isolation of the hospital. Immediate and systematic data collection enabled us to carry out an "acute" epidemiological survey of the accident. It is the first report of mass bromine intoxication in the medical literature. 91 patients with symptoms of bromine exposure were seen in the outpatient and casualty departments of the cantonal Hospital, but the clinical course was mild and self-limited in nearly all cases. One patient was admitted for 24 hours. The most common symptoms were upper respiratory tract symptoms, cough and headache. In 20-30% of cases these pesisted for more than three days, and sometimes up to one month. Recording the location of patients at the time when their first symptoms occurred made it possible to define the exposed area with precision. When the initial data collected in this "acute" fashion is reliable, it should be possible to undertake more elaborate epidemiological studies at a later stage if necessary.