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Biomedical subjects

J Walker

Publications and source records attributed to J Walker.

At least 541 records · Page 30Linked to original sources
PubMedDate not supplied

Predicting hospital-associated mortality for Medicare patients. A method for patients with stroke, pneumonia, acute myocardial infarction, and congestive heart failure.

We created a microcomputer-based system that uses characteristics of the patient at admission to predict death within 30 days of hospital admission for Medicare patients with stroke, pneumonia, myocardial infarction, and congestive heart failure. These conditions account for 13% of discharges and 31% of 30-day mortality for Medicare patients over 64 years of age. The system was calibrated on a stratified, random sample of 5888 discharges (about 1470 for each condition) from seven states, with stratification by hospital type to make the sample nationally representative. The predictors must be specially abstracted from the medical record. The cross-validated R2 for predictions is 0.14 to 0.25, which is better than the values for other systems for which we have data. Risk-adjusted predicted group mortality rates may be useful in interpreting information on unadjusted mortality rates, and patient-specific predictions may be useful in identifying unexpected deaths for clinical review.

Aged↗
PubMedDate not supplied

Intraocular lymphoma developing in a patient with Vogt-Koyanagi-Harada syndrome.

A 59-year-old Oriental male with chronic uveitis associated with vitiligo, poliosis, tinnitus and sunset glow fundus was diagnosed as having chronic Vogt-Koyanagi-Harada syndrome. He was treated successfully with steroids (systemic and sub-Tenon's) for two years, but then developed intractable vitritis and visual loss that worsened with the addition of azathioprine. A vitreous biopsy showed large B-cell lymphoma; a mass was also apparent in the subretinal space in the operated eye. Evaluation of the central nervous system was negative for lymphoma. Combined radiation treatment and chemotherapy resulted in dramatic resolution of the intraocular tumor. The possible role of immunosuppression in the development and progression of this tumor is discussed.

Humans↗
PubMedDate not supplied

A new use of the Simpson percutaneous atherectomy catheter: resection of retained valve cusps of an in-situ vein graft.

An in-situ saphenous vein graft occluded because of retained valve cusps. After aspiration thrombectomy, percutaneous transluminal balloon angioplasty was performed, but reocclusion occurred 11 months later. Following a second aspiration thrombectomy, the restenosed retained cusps were resected using the Simpson percutaneous atherectomy catheter. The graft remained patent until the patient's death from unrelated causes 6 months later.

Aged↗
PubMedDate not supplied

Unusual case of tracheal agenesis.

We describe the clinical presentation and pathological features of an unusual case of tracheal agenesis. The axial derivatives of the primitive foregut between the larynx and stomach were represented by a single structure featuring sequential segmentation into regions showing exclusively tracheal or esophageal differentiation in a pattern that is not easily classified by existing nosologic systems nor explained by the conventional hypothesis of dysontogenesis.

Abnormalities, Multiple↗
PubMedDate not supplied

Increased immunoreactive dynorphin and leu-enkephalin in posterior pituitary of obese mice (ob/ob) and super-sensitivity to drugs that act at kappa receptors.

Posterior pituitaries of obese mice (ob/ob) contained significantly more immunoreactive dynorphin (P less than .01) and leu-enkephalin (P less than .01) than their lean littermates. Drinking in obese mice was stimulated by 0.3%, and feeding by 10%, of the dose of ethylketocyclazocine, a kappa receptor agonist, needed to produce extra feeding and drinking in lean mice. Obese mice also showed greater and longer lasting suppression of ingestion after MR-2266, a kappa antagonist, than did lean mice. MR-2266 was much more effective than naloxone in suppressing schedule-induced polydipsia in rats. These results indicate that kappa receptors are involved in feeding and drinking and that obesity is associated with changes in these receptors and their ligands.

Analgesics, Opioid↗
PubMedDate not supplied

Elevation of calcitonin immunoreactivity in the pituitary and thyroid glands of genetically obese rats (fa/fa).

This paper contains the first demonstration of quantitative changes in the levels of calcitonin-like immunoreactivity in the pituitary. The concentration of calcitonin-like material in lean Zucker rats (?/+) was 0.42 +/- 0.09 ng/mg wet weight of pituitary. The pituitaries of obese rats (fa/fa) contained significantly greater levels (1.56 +/- 0.56 ng/mg wet weight). This 271% increase represents the first indication that pituitary calcitonin-like material may have a physiological role in genetically obese rats. Thyroidal calcitonin also elevated in the obese (111%). These large elevations in the calcitonin content of the glands of obese rats were not accompanied by significant elevations of calcitonin in the blood. This suggests that obese rats have problems with mechanisms for the release of calcitonin into the blood and might not be able to combat hypercalcemia as effectively as leans. However, this hypothesis remains to be tested.

Animals↗
PubMedDate not supplied

Women's experiences of transfer from a midwife-led to a consultant-led maternity unit in the UK during late pregnancy and labor.

PURPOSE: This study explored the experiences of women who were transferred from a midwife-led to a distant consultant obstetric unit before or during labor. BACKGROUND: Little attention is given to the psychological impact of transfer, particular when it takes place prior to labor. METHOD: Narrative and progressively focused interviews were conducted with 18 women who faced or experienced transfer prior to or during labor. The data were analyzed using a grounded theory approach. RESULTS: The core category in the transferred group was loss. This related to loss of choice, control, continuity, and support and was associated with anger and resentment. Distress appeared most common when transfer took place late in a healthy pregnancy when the mother recognized no risk to the baby. CONCLUSIONS: More attention needs to be paid to the psychological impact of transfer from midwife-led to consultant-led care, particularly where this involves a change of location or midwife.

Adolescent↗
PubMedDate not supplied

Expectations of independence and life satisfaction among ageing spinal cord injured adults.

PURPOSE: The present study offers information about independence and life satisfaction over the lifespan for individuals with traumatic spinal cord injuries. METHODS: The study uses the health expectancy methodology to estimate expectations of the remaining years of life that may be spent in states of independence and satisfaction with life. SUBJECTS: The cohort studied had all incurred a spinal cord injury between the ages of 25 and 34, between the years 1945 and 1990 in central and south-eastern Ontario. RESULTS AND CONCLUSIONS: The study found that levels of independence and quality of life in the sample conformed closely to those found in other similar studies with the spinal cord injured population: 22% reported their own functional status as dependent, and 22% reported fair to poor life satisfaction. Expectations of independence appeared to decline steadily over the five decades studied, while expectations of modified independence increased proportionally. Estimates varied significantly for those with paraplegia vs. quadriplegia, and those with complete vs. incomplete lesions. Expectations of life satisfaction appeared to change after the 30 year mark; at that point, the balance changed so that expectations of dissatisfaction outweighed expectations of satisfaction. Multiple regression showed that independence was related to lesion level, completeness and recency of injury, and both independence and satisfaction were related to marriage and employment.

Activities of Daily Living↗
PubMedDate not supplied

Allozyme diversity in Macbridea alba (Lamiaceae), an endemic florida mint.

Macbridea alba is a herbaceous perennial mint endemic to the panhandle region of Florida. We used starch gel electrophoresis to describe allozyme diversity and genetic structure in this federally threatened plant. Ten populations were analyzed, with an average sample size of 47 plants (range 41-48 plants) per population. Of the 22 loci analyzed, 11 (50%) were polymorphic, with an average of 36.2% of the loci polymorphic within populations. Gene diversity measures for the species (Hes = 0.121) and for the populations (Hep = 0.099) were slightly higher than means found for other surveyed endemic plants. Compared to nine previously analyzed woody mints, however, M. alba is genetically depauperate. Little genetic structure was evident within the species, with 92% of the total genetic variation found within populations. Genetic identities between population pairs were high (mean I = 0.98). The perennial life habit of M. alba and long-distance pollination by bumblebees may contribute to the maintenance of genetic diversity within this threatened species.

Electrophoresis, Starch Gel↗
PubMedDate not supplied

Effects of a single music therapy intervention on anxiety, discomfort, satisfaction, and compliance with screening guidelines in outpatients undergoing flexible sigmoidoscopy.

Screening flexible sigmoidoscopy (FS) is an effective tool for the detection of colon cancer. Nonetheless, persons are reluctant to undergo FS for a variety of reasons such as anxiety, discomfort, and the possibility of abnormal findings. Nurses caring for FS patients can implement interventions to allay anxiety and promote comfort in an effort to enhance satisfaction and future compliance. Music therapy is one nonpharmacologic intervention that has been shown to be effective in allaying anxiety, reducing discomfort, and promoting satisfaction in other patient populations. A two-group pretest, posttest experimental design with repeated measures study recruited 64 subjects undergoing FS from one Midwestern tertiary care center. Subjects were randomly assigned to a control condition of usual procedural care or to an experimental condition of music therapy during the examination. State and trait anxieties were measured at pretest. State anxiety, discomfort, satisfaction, and perceived compliance with future screening were measured after the procedure. Subjects in the music group reported less anxiety and discomfort than subjects in the control group. There were no differences on satisfaction ratings or perceived compliance with screening guidelines. Nurses caring for patients undergoing screening FS can offer music therapy as one nonpharmacologic intervention to ameliorate anxiety and reduce discomfort.

Analysis of Variance↗
PubMedDate not supplied

Early versus delayed stabilization of pediatric femur fractures: analysis of 387 patients.

OBJECTIVES: To assess the effect of timing of femur fracture stabilization on pulmonary complication rates in pediatric trauma patients. DESIGN: Retrospective review. SETTING: Level I trauma center. PATIENTS: Three hundred eighty-seven previously healthy patients from zero to fifteen years of age with traumatic diaphyseal femur fractures. INTERVENTION: Femur fracture stabilization: early (less than twenty-four hours after injury) in 213 patients and late in 174 patients. MAIN OUTCOME MEASUREMENTS: Age, sex, GCS (Glasgow Coma Score), AIS/ISS (Abbreviated Injury Score/Injury Severity Score), timing of fracture stabilization, duration of mechanical ventilation, intensive care unit stay, and hospital stay were recorded. Pulmonary complications, including pneumonia, respiratory distress syndrome, and pulmonary embolus, were recorded. RESULTS: Thirteen patients developed pulmonary complications. Twelve of these had severe head injuries (GCS < or = 8). One had sustained an upper cervical spine fracture that resulted in quadriplegia. Statistical analysis revealed GCS, GCS < or = 8, ISS, and head and neck AIS to be significant predictors of pulmonary complications. Early stabilization of femur fractures had no apparent effect on the pulmonary complication rate. CONCLUSIONS: Pulmonary complications are rare in pediatric femur fracture patients. Patients with severe head injuries (GCS < or = 8) or cervical spinal cord injuries are at high risk for pulmonary complications. The timing of femur fracture stabilization does not appear to affect the prevalence of pulmonary complications in these patients.

Adolescent↗
PubMedDate not supplied

Ultrasonography of the unossified patella in young children.

Ultrasonography has become a useful technique to assess the cartilaginous hip of the newborn. We applied this technique and found that it gave useful information in helping to locate the unossified patella in two cases of congenital dislocation of the patella.

Contracture↗