Quantitative and qualitative video analysis of infants feeding: angled- and straight-bottle feeding systems.

OBJECTIVE: To determine whether an angled-bottle feeding system is more effective than a straight-bottle feeding system in facilitating the medically recommended semiupright infant posture and to determine whether an angled bottle promotes improved ergonomic alignment and comfort for the feeder. STUDY DESIGN: On two consecutive days, 23 pairs of parent-infant teams, seated in an ergonomic chair, were videotaped at the same time of day, during which infants were fed by their parents with either an angled or a straight bottle (presented in balanced order) fitted with the infants' regular nipple. Infants were given their regular type and amount of formula. RESULTS: The angled bottle provided a higher level of satisfaction compared with the straight bottle. Less gastric discomfort occurred with the angled bottle versus the straight bottle when each was compared with the bottle used at home. In addition, feeders assumed ergonomically sound positions. CONCLUSION: This study indicates that an angled bottle is preferable to a straight bottle because it encourages more physiologic positioning of the infant, improves the comfort level of the feeder, improves ergonomic feeding performance, and decreases the need for burping.

Oxygen affinity of hemoglobin and peripheral nerve degeneration in experimental diabetes.

Peripheral neuropathy remains a major complication of diabetes. Numerous etiological theories of metabolic and/or vascular disturbances have been suggested including decreased endoneurial oxygen tension with presumed tissue hypoxia. Increases in the affinity of hemoglobin for oxygen (Hb-O2 affinity) may also produce tissue hypoxia and such Hb-O2 affinity changes have been implicated in the pathogenesis of diabetic microangiopathy. In order to test whether affinity hypoxia might contribute to the development of diabetic peripheral neuropathy, we have utilized a rat model of high and normal Hb-O2 affinity produced by backcrossing animals with increased and decreased levels of 2,3-diphosphoglycerate (DPG). Diabetes was induced in ten high and ten low DPG animals with a tail vein injection of 55 mg/kg streptozotocin (STZ). Five animals in each group were treated with 2.4 U protamine zinc insulin (PZI)/day while the remaining animals were untreated. All rats were killed after 30 days, sections of tibial and sural nerve were rapidly removed and processed for teased fiber analysis. A minimum of 125 axons were assessed per nerve for E degeneration (myelin ovoids) using the classification developed by Dyck et al. Untreated animals, regardless of DPG levels, demonstrated 0% neuropathy. In contrast, all insulin-treated animals showed degeneration (0.4-17%) that inversely correlated with the DPG level (r = -0.59, P less than 0.04). The results of this study suggest that the level of RBC DPG (and presumably the Hb-O2 affinity) with its attendant effect on tissue oxygen release may play a role in the development of peripheral neuropathy in STZ-induced diabetic rats treated with insulin.

Neuroscience and occupational therapy: vital connections. 1989 Eleanor Clarke Slagle lecture.

This paper presents the hypothesis that in-depth knowledge of the neurosciences serves as a common denominator that enhances our ability to interpret all aspects of human behavior. Neurobiological information can be used to design research to evaluate our existing treatment philosophy and methodology and to develop new theories and technology. Because occupational therapy addresses widely divergent diagnostic populations, three separate areas along the practice continuum were selected to demonstrate the application of neurobiological concepts: (a) neuroimmunomodulation, (b) organic bases of psychopathology, and (c) traumatic brain injury. Philosophical statements regarding effective methods of teaching neurobiology to occupational therapists are included.

Distribution of thyrotropin-releasing hormone (TRH) in the hippocampal formation as determined by radioimmunoassay.

The distribution of thyrotropin-releasing hormone (TRH) in the hippocampal formation was determined using a radioimmunoassay (RIA) specific for TRH. RIA of hippocampal subregions revealed that the CA3 region of the hippocampal formation contained the highest amount of TRH, followed by intermediate levels in region CA1 and the dentate gyrus. The hilus and subiculum contained the lowest levels. The issue of whether hippocampal TRH is derived from extrinsic and/or intrinsic sources was evaluated by making lesions of the major subcortical afferent to the hippocampus, the fornix pathway. Analysis of the hippocampal formation by RIA revealed that the ventral hippocampus contains higher levels of TRH than the dorsal hippocampus (6.01 +/- 0.62 pg/mg tissue weight vs 1.11 +/- 0.19 pg/mg tissue weight). Lesions of the fornix produced significant decreases in ventral TRH to 52.9% of its control level and in dorsal TRH to 28.8% of its control level. The results from these studies suggest that (1) there is a differential distribution of TRH in the hippocampal formation, (2) the hippocampal formation might be composed of extrinsic and intrinsic sources of TRH, and (3) extrinsic sources of TRH might enter the hippocampus via the fornix pathway. In addition (4) the greater post-lesion decrement in ventral vs dorsal hippocampal TRH suggests that TRH fibers traversing the fornix innervate the ventral hippocampal formation in preference to its dorsal counterpart.

Olfaction in health & disease.

The significance of olfaction is frequently overlooked by health professionals. The purpose of this presentation is to briefly review the neurophysiology of olfaction, survey the relevant research, and present specific implications for occupational therapists working in both physical disabilities and psychiatric settings.