Secondary structure and thermostability of the photosystem II manganese-stabilizing protein of the thermophilic cyanobacterium Synechococcus elongatus.

The secondary structure of the manganese-stabilizing protein of the thermophilic cyanobacterium Synechococcus elongatus in solution was investigated by Fourier-transform infrared (FT-IR) and circular dichroism (CD) spectroscopies. Both methods showed a high proportion of disordered structure (40-43%) and a relatively small amount of beta-sheet (23-24%) and alpha-helix (17-19%). The conformation of the protein remained essentially unchanged at temperatures up to 70 degrees C. Unfolding of the protein occurred at higher temperatures and FT-IR spectroscopy revealed that beta-sheet was more strongly unfolded than alpha-helix at 76 degrees C. The protein largely lost the ordered secondary structures at 90 degrees C, but, when cooled down to 30 degrees C, regained its original conformation. Thus, the cyanobacterial protein is very thermostable and its denaturation at an extremely high temperature is reversible.

Fusiform basilar artery aneurysm in a child.

A giant fusiform aneurysm of the basilar artery was present in a 10-year-old boy with a 2-year history of intermittent headaches and the acute onset of neurologic signs. Elevated sedimentation rate, cerebrospinal fluid pleocytosis, and an apparent response to corticosteroid therapy suggest a chronic inflammatory vascular process. The uniqueness of this aneurysm in a child and the possible underlying arteriopathies are discussed.

Perceived first contact care for disabled children.

In a mail-back questionnaire survey, 169 mothers of myelodysplastic children were asked whom they would contact first for each of 24 health-related problems. These problems ranged from earaches to shunt obstruction to sexual counseling. All children were being followed in a comprehensive care clinic at a regional center; however, nearly half of these families lived in rural areas distant from the clinic. Eighty percent of children were said to have local physicians. Mothers tended to perceive clinic staff and specialists for first contact care according to severity of the child's motor paralysis, the greater the child's hospitalization experience, and the shorter the travel time from home to clinic. However, when travel time was controlled, there was no difference in overall perceptions for those mothers living more than 90 miles away from the clinic. In a second survey to 91 physicians designated as the "child's local doctor" and a third survey to the 27 clinic staff members, respondents were asked whom should mother contact first for each of the 24 health-related problems. The clinic staff tended to prefer itself, despite the general policy of the clinic to encourage families to utilize community resources, including their physicians. Local physicians tended to prefer themselves over clinic staff, a position consistent with the philosophy of primary care to the chronically disabled child.

Experiences with phrenic nerve pacing in children.

We report a series of four spinal cord-injured children with ventilator dependency who were implanted with radiofrequency phrenic nerve pacers. At injury, their ages ranged from 6 to 9 years. Implantation occurred from 15 to 47 months following injury. The longest term of pacing has been 59 months. One patient, who was being paced full-time, died suddenly at 32 months of a viral myocarditis. Two patients underwent bipolar phrenic implantation in the neck, while two other patients underwent bilateral thoracotomy with monopolar electrode implantation in the mediastinum. There have been no complications related to pacer dysfunction in the postoperative course. Selective pacing schedules have been developed to minimize problems related with external mechanical ventilation. Radiofrequency phrenic nerve pacing is of value in the complete rehabilitative management of these severely disabled children.

Checklist for the prescription of slings for the hemiplegic patient.

The wide variety of hemiplegic sling designs, the lack of a uniform approach to sling selection, and the paucity of research data in this area have tended to make prescribing a sling a subjective process. Based on clinical experience and a comprehensive literature review, the authors propose a checklist for examining hemiplegic slings. The Checklist, which includes 19 desirable and 4 undesirable characteristics of slings, provides a more objective basis for comparing sling designs, warns of potential hazards, and facilitates the thorough examination of hemiplegic slings. The uses and limitations of the Checklist are discussed.

Clinical evaluation of the effects of ketamine sedation on pediatric dental patients.

This study was undertaken to determine the dosages, treatment times and side effects of ketamine HCI with and without two benzodiazepines when used for sedation on a group of precooperative children at the UCLA Children's Dental Center. Ketamine was evaluated when used alone, and in conjunction with two benzodiazepines, diazepam or a new water-soluble midazolam. An anti-muscarinic, atropine or glycopyrrolate, and nitrous oxide-oxygen were included in all sedations. Mean treatment times were increased significantly when ketamine and a benzodiazepine were used in combination. Additionally, mean ketamine dosages were decreased significantly when ketamine was utilized in combination with a benzodiazepine. All children tolerated the sedation well and there were no severe adverse reactions. Side effects included nausea, vomiting, and a rise in post-operative temperatures.

Deep pockets or blueprint for change: traumatic brain injury (TBI) proactive strategy.

The Pacific Conference scheduled for October 1-3, 1988, is a critical event in the development of an integrated community-based plan for a comprehensive continuum of services to address the "silent epidemic," Traumatic Brain Injured (TBI). This paper provides insights of the complex nature and the special problems faced by the TBI survivors; their families, natural supports and caregivers, as well as the health, social and educational care providers in Hawaii. Process for the development of the community plan is presented.

Polio survivors in Hawaii: new problems of health and disability.

U.S. mainland studies reveal an alarming rise of progressive disability reported by long-term polio survivors. To determine if polio survivors residing in Hawaii were experiencing similar problems, this study of 100 volunteers was undertaken. Extensive interviews and physical examinations were performed. Results indicate that many patients were complaining of new or greater disability due to late complications of polio or medical conditions unrelated to polio. Twenty percent appeared at greater risk for having post-polio syndrome (PPS). Over half described mobility that was less than fully independent. Subjects voiced a clear need for specialized health, social and rehabilitative services. Consistent with Mainland reports, polio survivors in Hawaii are demonstrating changes in disability that challenge the traditional notion that polio is a static, permanently stable neurologic condition.

Epidemiology of ocean sports-related injuries in Hawaii: 'Akahele O Ke Kai'.

Before attempting to prevent ocean activity injuries, as well as to improve treatment strategies, more information is needed regarding the numbers of injuries that are geographic and activity specific and the identification of persons at risk for such injury. Data on 276 injuries that occurred during ocean sports activities on the islands of Oahu and Hawaii over a 10-month period are presented. The injuries were mainly related to swimming and board-surfing, although serious injuries were found for almost all types of sports activities. The majority of those injured were young adult men who were local residents. Over 10% of the injuries required hospitalization, including 4 fatalities due to drowning and 5 spinal cord injuries due to trauma or to SCUBA-related, decompression incidents. Our study identifies the need for determining an estimate of the number of persons engaging in ocean sports, establishes the need for a single reporting system for injuries, determines potential risk factors, and suggests targets for prevention.

Bowel training for children with neurogenic dysfunction: a follow-up.

Fifty children with neurogenic bowel dysfunction and stool incontinence received in patient bowel regulation training and were interviewed an average of 1.2 years later. Twenty-eight were males. Mean age was 13.5 years (range 5.6 to 18.9 years). Of the 50 children, 27 (54%) had myelomeningocele; 21 (2%), spinal cord lesion; and 27/2 (4%), repaired imperforate ani. Frequency of stool incontinence decreased from 1.8 episodes for the week prior to discharge to 0.9 episodes for the same period preceding follow-up interview (p less than 0.025). Significant changes occurred in the recommended bowel program in order to accommodate individual home environment and family life styles. Contributory factors accounting for these changes are discussed in light of specific guidelines for the rehabilitation team.

Study on the mechanism of the appearance of noise effects.

This study was undertaken to investigate the dose-response relationship between the biological effect and noise exposure, and to consider the mechanism of the appearance of noise effects. Rats were exposed to noise at intensities of 60 dB (A), 80 dB (A) and 100 dB (A) for 240 min and examined for the change of activities of dopamine-beta-hydroxylase (DBH) in serum and adrenal glands. Plasma cyclic adenosine 3',5'-monophosphate (c-AMP) levels were also measured. Some rats were given 6-hydroxydopamine (6-OHDA) as a chemical sympathectomyzing agent 20 h before noise exposure in order to consider the mechanism of the appearance of noise effects. By noise exposure, serum DBH activity was significantly (P less than 0.01) increased at each intensity compared with the control group, but there were no remarkable changes in adrenal DBH activity. Plasma c-AMP level was also significantly elevated in response to the noise stress. When the rats, which had been pretreated with 6-OHDA, were exposed to noise with an intensity of 100 dB (A), the response of serum DBH activity was no longer observed. Therefore it is suggested that the effect due to noise exposure appears through the post-ganglionic sympathetic nerve fiber.

Changes in cerebral norepinephrine induced by vibration or noise stress.

To investigate the effects of whole body vibration on the central nervous system, rats were exposed to various whole body vibrations and examined for changes in the levels of norepinephrine (NE) in whole brain or regions of the brain. Whole brain NE had decreased significantly (P less than 0.05) after an acceleration of 5.0G with a frequency of 20 Hz; and the decrease was also observed in the hypothalamus (P less than 0.01) and the hippocampus (P less than 0.10). Exposure to noise [100 dB (A)] caused a significant decrease in NE. This decrease related particularly to a significant decrease in midbrain NE (P less than 0.05) and a non-significant decrease of NE in the hypothalamus.

Scavenging of Active Oxygen Species by Glycated Proteins.

Scavenging of active oxygen species by glycated proteins was investigated. Glycated proteins were prepared from bovine serum albumin (BSA), insulin, and lysozyme incubated with glucose. Glycated BSA at concentration of 0.5% scavenged 34% of hydroxyl radicals by ESR experiments using DMPO as a spin-trapping reagent. The ability to scavenge hydroxyl radicals by glycated BSA was higher than that by BSA. Hydrogen peroxides also were largely scavenged with an increase in the concentration of glycated proteins. However, the ability to scavenge superoxides by glycated BSA was lower than that by BSA because glycated proteins produced superoxides. Experiments using model compounds such as Amadori compound and caproyl pyrraline suggested that the scavenging ability of glycated proteins against hydroxyl radicals depends on Maillard reaction products in the advanced stage, while the ability against hydrogen peroxides is dependent upon Maillard reaction products in the early stage and brown pigments.

Bleeding control after extractions in a patient with aplastic anemia during bone marrow transplantation: report of case.

This report describes a method of bleeding control at dental extraction sites using medicaments (thrombin, cocaine, Amicar, Surgicel) in conjunction with a dental appliance containing vinyl polysiloxane silicone putty (Optosil) to provide greater coverage and pressure at the extraction sites. The acrylic splint was used to control bleeding in a 15-year-old male, with an aplastic pancytopenia anemia, who had required removal of severely mobile exfoliating teeth prior to a bone marrow transplantation procedure.

Skin breakdown in patients with myelomeningocele.

An attempt was made to quantify longitudinal morbidity and identify risk factors associated with high rates of skin breakdown in patients with myelomeningocele. Based on annual evaluations, 227 of 524 patients accounted for 468 positive observations including classic decubiti, abrasions, burns, and ammoniacal dermatitis. Forty-two percent (196) of skin breakdown was attributed to excessive pressure; 57% (267) to other causes; and 1% (5) to unknown causes. Prevalence curve revealed a steady rise from infancy to age 10 years, at which point rates varied between 20-25%. Longitudinal morbidity curves of first skin breakdown showed a tendency of lesions over the perineum or gibbus to appear more frequently in the presence of higher paraplegia (generalized Savage or Mantel-Cox, p = 0.05). However, mildly paraplegic and partially insensate patients exhibited relatively higher rates of breakdown over the lower extremities compared to more paraplegic patients. Higher rates of breakdown were associated with other characteristics such as mental retardation, large head size, kyphoscoliosis, and chronic soiling. Data confirm the high prevalence of skin breakdown in patients with myelomeningocele and reflect an overall influence of growth and development.

Motorized wheelchair driving by disabled children.

Thirteen children with physical disabilities, normal intelligence and stable family situations were studied to learn whether children under age 4 years could learn competent control of a motorized wheelchair. Their mean age was 31.3 months (range 20 to 37 months). There were six girls and seven boys. Each child required adaptive seating to manipulate the control stick in a conventional motorized wheelchair. Without specific training instructions, parents introduced the wheelchairs under pleasant circumstances at home. Daily logs and engine-hour-meters indicate that 12 children learned seven pre-established driving skills within a mean cumulative period of 34.4 hours (range 6.6 to 168 hours) distributed over an average 16.3 days (range 3 to 50 days). Actual cumulative wheelchair movement averaged 8.1 hours (range 1.7 to 26.1 hours). All learned a cluster of four to five skills over a one to five day period. Start-stop and circling were the two initial skills in all but one case. In four children, the first skill appeared after a latent period of 5, 6, 12 and 43 days. Children as young as 24 months can learn to drive motorized wheelchairs. Because of the theoretical importance of approximating normal gross motor milestones, powered mobility should be considered an early rehabilitative intervention for physically disabled children.

Community education on stroke.

A programme of community education on stroke in Micronesia is based on the use of brightly illustrated posters with a limited content of written material in the native languages. This approach has been favourably received by the people.