Biomedical subjects
Publications and source records attributed to D Maurer.
3-month-old infants made 2 types of discrimination with their peripheral vision. They discriminated between grossly different figures placed as far out as 30 degrees toward the periphery, and they discriminated between more subtly different figures, which differed only in the shape of their internal elements, out to 10 degrees. The results imply that infants can readily process stimuli with peripheral vision.
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The Autobac I system was used to evaluate the antibiotic susceptibility pattern of methicillin-resistant Staphylococcus aureus isolates. The results of the Autobac I were compared with the results of the disk diffusion method. The disk diffusion susceptibility pattern showed resistance to methicillin/oxacillin, penicillin, erythromycin, clindamycin, and kanamycin. All isolates were susceptible to cephalothin, chloramphenicol, tetracycline, and gentamicin. There was at least 96% agreement using the Autobac I system with all antibiotics except methicillin and clindamycin. Seventy percent of 57 isolates were recorded as susceptible to methicillin, whereas 9% had an intermediate susceptibility. With clindamycin, 14% were recorded as susceptible and 7% were recorded as intermediate. Upon prolonged incubation of the Autobac I cuvette, the agreement between the two methods was 44% for methicillin and 93% for clindamycin. Changes in the environmental conditions, such as use of 5% sodium chloride broth and a 32 degrees C incubation temperature, did not increase the detection of methicillin-resistant isolates by the Autobac I system.
6 1-month-old infants and 6 2-month-old infants each viewed 3 faces (his mother's, a strange woman's, and a strange man's) while his eye movements were recorded by corneal photography. The 1-month-olds fixated away from the faces most of the time, and they looked at their mothers even less often than at the strangers. When they did fixate a face, they usually chose a limited portion of the perimeter. By constrast, 2-month-olds fixated the faces most of the time, looked at more features, and were more likely to look at internal features, especially the eyes. This scanning resembles that reported previously for 2-dimensional shapes, although in some respects it appears unique to faces.
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A systematic, strict appraisal was made of 100 patients, after preliminary clinical trials suggested that some patients with pain could be helped by peripheral nerve stimulation. Transcutaneous stimulation of different nerve trunks was done with a special electrical stimulation device with various selected electrical parameters. More than half of the patients experienced some relief; in many, this effect was obtained by stimulating nerves distant from the area of referred pain. Pain relief lasted for varying periods after stimulation. The maximum benefit was noticed after certain specific parameters were reached for each patient. A few patients had response decay, gain or worsening. Results differ to some degree from previous reports. The results seem encouraging for the treatment of certain forms of intractable pain.
Twenty-three patients underwent implantation of a stimulator system and were followed for 6-20 months. Twenty patients estimated between 50% and 100% pain relief. The effect was largely consistent and reproducible. Reduced drug intake and improved social performance were associated with subjective improvement. The surgical technique is given, complications are analyzed and parameters are discussed.
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Explore the source record for details and available documents.
Retrosternal dislocations of the clavicle have been reported previously in adults throughout the orthopedic literature. However, in children few cases have been noted in either the pediatric, emergency, or orthopedic literature. The potential for great vessel injury as well as acute airway compromise makes the retrosternal disruption of the sternoclavicular joint a surgical emergency that must be diagnosed quickly. Diagnosis is enhanced by the cephalic tilt view and by computed tomography (CT scan), as planar x-ray and tomography do not always reveal this potentially life-threatening condition. Surgical consultation must be sought acutely; however, management may need to begin prior to definitive repair. Emergency management begins by suspecting the injury, and with immediate airway and circulatory support for the patient.
We evaluated the subcortical pathways' contribution to human adults' horizontal OKN by using a method similar to that used previously with cats (Harris & Smith, 1990; Smith & Harris, 1991). Five normal adults viewed plaids composed of two drifting sinusoidal gratings arranged such that their individual directions of drift were 60 deg or more from the direction of coherent motion of the overall pattern. Physiological evidence indicates that under monocular viewing, nasalward coherent motion gives advantage to any crossed subcortical contribution while temporalward coherent motion minimizes it. We recorded horizontal eye movement by infrared reflection and asked subjects to report the perceived direction of motion. During both binocular and monocular viewing, the direction of the slow phase of OKN fell closer to the direction of coherent movement than to that of the oriented components. Monocular viewing produced no nasal-temporal asymmetries in the influence of coherent motion on the direction of OKN. This suggests that in humans the influence of coherent motion is mediated primarily by cortical mechanisms and, unlike in cats, with little or no involvement of subcortical mechanisms in the generation of horizontal OKN.
We tested 1-month-olds for cross-modal transfer of shape between touch and vision using a procedure described by Meltzoff and Borton, but including controls for side bias and stimulus preference. In Experiment 1 (N = 48), infants' looking times to smooth and nubby visual stimuli were not influenced by previous oral exposure to one of the shapes during the preceding 90 s, except for an effect on the first test trial in one group; this effect could have been due to limited cross-modal transfer, to Type 1 error, or to side bias, possibly interacting with a small stimulus preference. The failure of that effect to replicate in a group (N = 16) with less side bias (Experiment 2) suggests that it was not due to cross-modal transfer. Experiment 3 (N = 32), an exact replication of Meltzoff and Borton's experiment, also failed to yield evidence of cross-modal transfer. Overall, there is not good evidence that 1-month-olds can transfer information about these shapes from touch to vision. Future studies exploring the ability to transfer information about other shapes will be easier to interpret if they include controls for side bias and stimulus preference.
In atopic individuals, cutaneous antigen-presenting cells (APC), i.e. Langerhans' cells (LC) and dermal dendritic cells (DDC), frequently display anti-IgE reactivity. While earlier observations suggested that this phenomenon results from the binding of (complexed) IgE to the low affinity IgE receptor (Fc epsilonRII/CD23), recent evidence exists that LC and DDC, as well as peripheral blood dendritic cells and monocytes from atopic individuals, can bind monomeric IgE via the high-affinity receptor for IgE (Fc epsilonRI). We have now found that Fc epsilonRI, both quantitatively and qualitatively, is the pivotal serum IgE-binding structure on APC of atopic individuals, that Fc epsilonRI on APC functions as allergen-focusing molecule and that allergens are more efficiently taken up, processed and presented to T cells following targeting to APC via Fc epsilonRI compared to allergen binding to APC in the conventional manner. In vivo, Fc epsilonRI-IgE-dependent allergen presentation may critically lower atopic individuals' threshold to mount allergen-specific T cell responses. This would result in the perpetuation of allergen-specific IgE production (type I reactions) and perhaps even in the occurrence of T-cell-mediated delayed-type hypersensitivity reactions in allergen-exposed tissues.
PURPOSE: We measured the extent of the monocular visual fields of children deprived of normal visual experience and examined the influence of the timing and duration of deprivation, of whether deprivation was monocular or binocular, of having patched the fellow eye, and of optical factors. METHODS: The Goldmann perimeter and a 6.4' stimulus of either 31.8 cd/m2 (target 12e) or of 318 cd/m2 (target 14e) were used to test 44 children treated for a dense and central cataract in one (n = 25) or both (n = 31) eyes that developed before 6 years of age. Then, the influence of optical factors was assessed in two adults treated for a late-onset, unilateral cataract and in two children treated for unilateral congenital cataract. RESULTS: Compared with age norms or the normal fellow eye, all children treated for cataract showed a restricted field, especially temporally, even when deprivation began as late as 6 years of age and lasted less than 6 months. The restrictions were larger than those shown by the adults who developed cataracts. The restrictions were larger after longer deprivation and monocular deprivation than after binocular deprivation. However, children who regularly patched the fellow nondeprived eye and, therefore, experienced less interocular competition, exhibited smaller restrictions temporally. Neither visual acuity nor optical factors could account for all of the restrictions in the deprived children. CONCLUSIONS: The development of the visual field is vulnerable to the effects of deprivation, especially to unilateral deprivation and to long deprivation. The losses likely reflect alterations in the visual pathways subserving peripheral vision.