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Biomedical subjects

J Smith

Publications and source records attributed to J Smith.

At least 1,549 records · Page 86Linked to original sources
PubMedDate not supplied

The Jk(a-b-) phenotype in New Zealand Polynesians.

The Kidd locus phenotype Jk(a-b-) was detected in 0.9 percent of Polynesians living in New Zealand. Over a period of 13 years, nine examples of anti-Jk3 were detected, one of which caused a delayed hemolytic transfusion reaction. Other examples resulted in mild hemolytic disease of the newborn. The anti-Jk3 reacted as an inseparable antibody, confirmed that inheritance of the Jk(a-b-) phenotype was best explained by the presence of a silent Jk allele.

Alleles↗
PubMedDate not supplied

Extended storage of single-donor platelet concentrate collected by a blood cell separator.

Use of a sealless blood pathway in a blood cell separator (CS-3000, Fenwal) permits collection of platelets in a "closed system" when saline and anticoagulant solutions are integrally attached; this in turn allows storage of instrument-collected platelet concentrates (PCs) beyond 24 hours. To evaluate extended storage of high yield PCs, cells collected with the instrument were stored (200 ml plasma) for 8 days (flatbed agitation) in either 3-liter polyvinylchloride (PL 146) containers (n = 6), polyolefin bags (PL 732) (n = 8), or two 1-liter polyolefin (double PL 732) containers (n = 8). A mean of 4.45, 4.09, and 3.94 X 10(11) platelets were stored in PL 146, single PL 732, and double PL 732, respectively; total white cells per container averaged 0.3, 0.2, and 0.2 X 10(9) for the three container systems. By day 1, platelet pO2 dropped to 14 and 16 torr in PL 146 and PL 732 PCs (pCO2, 127, and 82 torr). In contrast, double PL 732 maintained high pO2 (approximately equal to 80 torr) and low pCO2 (approximately equal to 30 torr) through day eight. Glucose declined at faster rates in PL 146 and single PL 732 containers, while lactate increased more rapidly (338 and 197 mg/dl of lactate on day four vs. 116 mg/dl for double PL 732 units). Morphology scores dropped from 400 to 98 (PL 146) and 216 (PL 732) at day four (pH values of 6.3 and 7.0), while a score of 330 was seen in double PL 732 PCs.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Platelets↗
PubMedDate not supplied

Plasma separation using a hollow fiber membrane device.

A disposable hollow fiber device was evaluated by collecting approximately 550 ml of normal donor plasma (n = 43) and by performing sham (n = 10) and therapeutic (n = 12) plasma exchanges. Blood was processed at 70 ml per min, and plasma flux averaged 23 (collection) and 25 (exchange) ml per min (mean separation efficiencies of 52 and 60%, respectively). The procedures were tolerated well by all donors and patients. The plasma hemoglobin concentration in separated plasma averaged 1 mg per dl, and cell contamination was negligible (mean of 1, 3, and 6 RBCs, platelets and WBCs/microliter, respectively). There was no evidence of in vivo classical or alternative pathway complement activation as assessed by total hemolytic complement generation (CH50), alternative pathway hemolytic activity (AP50), C3 conversion, or C5 activation, nor were unexpected changes seen in the results of laboratory tests performed after the procedure. Sieving coefficients during sham plasma exchange averaged as follows: albumin, 1.03; IgM, 1.0, IgG, 1.0; IgA, 0.98; factor V, 1.07; factor VII, 0.89; factor VIII, 1.05; and factor IX, 1.19. The device appears to be useful for separation of cell-free plasma from blood during therapeutic plasma exchange procedures.

Blood Component Removal↗
PubMedDate not supplied

Carboplatin-induced immune hemolytic anemia.

BACKGROUND: A case of acute hemolysis following therapy with carboplatin, an anticancer chemotherapeutic agent, was investigated. Hemolytic anemia has been associated with cisplatin, a related drug, but not with carboplatin. CASE REPORT: An 8-year-old boy was treated for an astrocytoma by monthly intravenous injections of carboplatin. Lower back pain was noted after 26 monthly injections, and overt intravascular hemolysis occurred after the 27th injection. The direct antiglobulin test was 4+ with anti-IgG and 1+ with anti-C3d. RESULTS: Blood samples obtained on Days 28 and 56 after the last injection were tested for carboplatin-dependent antibody. The direct antiglobulin test was 1+ with anti-IgG; the eluate was 1+ with and without carboplatin. The serum indirect antiglobulin test was negative in the absence of carboplatin, 3+ to 4+ in the presence of carboplatin, and 1+ with carboplatin-coated cells. Day 56 serum antibody titer was 64 (agglutination at 37 degrees C), 512 (indirect antiglobulin test) in the presence of carboplatin, and 8 (indirect antiglobulin test) with carboplatin-coated cells. CONCLUSION: The findings indicate a carboplatin-induced antibody reacting in vitro by a complex mechanism combining elements of "immune complex," drug adsorption, and autoantibody mechanisms. Drug-dependent hemolysis is a previously unreported but potentially serious complication of carboplatin therapy.

Anemia, Hemolytic, Autoimmune↗
PubMedDate not supplied

The effects of dexamethasone on the differentiation and the fertilisation of the germinal primordium in the chick embryo.

We showed that, in the chick embryo, the fertilisation of the attractive germinal epithelium by primary germ cells can be represented by a three-dimensional diagram in which the space and time co-ordinates are graduated in terms of the segmentation of the axial and paraxial mesoderm. We thus established that the differentiation of the coelomic epithelium into an attractive germinal epithelium and the fertilisation of the gonadal primordium both occur by mechanisms that are tightly linked to somitogenesis. In the continuous presence of a constant concentration of Dexamethasone, a marked inhibition of the rate of fertilisation of the gonadal primordium was observed. A mathematical analysis of the mode of action of the inhibitor revealed the progressive establishment of a competition between Dexamethasone and the molecule(s) responsible for the process of attraction. Given the chemical nature of the inhibitor, we propose that the endogenous factor that triggers the first step of the differentiation of the germinal primordium is a steroid-containing complex.

Animals↗
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Assuring quality and access in advanced practice nursing: a challenge to nurse educators.

In an environment characterized by a projected over-supply of primary care providers and a public seeking higher quality, cost-effective care, advanced practice nurses will be measured not only by their comparative value in delivering conventional primary care, but also by the uniqueness of their contributions to health outcomes. These value-added skills, distinctive to nursing practice at all levels, include health education, disease prevention, health promotion, community resource access, and partnerships with patients. Government, private payors, and national and state regulators all authorize increasingly independent practice by advanced practice nurses. When advanced practice nurses assume such fully accountable primary care roles, their title and certification should be distinctive to that level of practice. A Doctor of Nursing Practice (DNP) degree would signal to the public that nurses--at their highest practice competency--are at the same level as other health professionals holding doctorates (such as MD, DDS, or PharmD).

Clinical Competence↗
PubMedDate not supplied

Vascularized fibular grafts for salvage reconstruction of clavicle nonunion.

Three cases of persistent nonunion of the clavicle with segmental bone loss were treated with autogenous, vascularized fibular grafts. In each case, the patient presented with pain and shoulder dysfunction after an average of 3.7 procedures. Each case was characterized by segmental bone loss that failed to unite after treatment of clavicle nonunion by traditional means. Union was achieved in all 3 cases. Average follow-up was 2.8 years. Both pain and shoulder function were improved with the procedure. To date, the use of vascularized fibular grafts has not been described in clavicle reconstruction. We believe that vascularized fibular grafting may be used successfully as a salvage procedure when traditional means of achieving union have failed.

Adult↗
PubMedDate not supplied

Effect of low-level body burdens of lead on the mental development of children: limitations of meta-analysis in a review of longitudinal data.

The effect of low-level body burdens of lead on the intelligence of children, as measured by intelligence quotient (IQ), was assessed. We reviewed 35 reports from five longitudinal studies conducted in the United States and Australia. In each of these studies, infants were followed for 58 mo or less. The study populations consisted of low- and middle-socioeconomic-class infants who had low-level exposure to environmental lead. Blood-lead levels were measured in a standard fashion at various times, beginning in the prenatal period, and intelligence was first measured at 6 mo of age and was followed by subsequent assessments. Studies were assessed for quality by a review panel blinded to the identity of the investigators and their affiliations. Efforts were made to pool the data with meta-analytic techniques, but efforts were unsuccessful because the methods used to analyze and report data were inconsistent. Inconsistencies were as follows: (a) there were few instances in which IQ and blood-lead levels were measured at comparable times in different studies; (b) incompatibilities existed among the studies, including differences in independent variables, data transformations, and statistical parameters reported; (c) results conflicted when measurement intervals were comparable (i.e., heterogeneity); (d) patterns of regression and correlation coefficients were inconsistent; and (e) data were insufficient to interconvert the parameters reported. Consequently, definitive conclusions regarding the effect of low-level body burdens of lead on IQ could not be determined from the longitudinal data. Examination of the weight of the evidence from this and other studies, however, suggests an adverse relationship of lead on the intelligence of children.

Bias↗
PubMedDate not supplied

Methodological comment: temporal stability of older person's spontaneous self-definition.

Open-ended tasks such as the "Who am I?" (Bugental & Zelen, 1950) or the Twenty Statement Test (Kuhn & McPartland, 1954) have facevalidity with regard to assessing content and dimensions of self-definition. Examined in the present study were questions about short-term temporal stability. Theory suggests that measures of the self may better reflect intraindividual variability than personality tests. Free-response and card-sort versions of the "Who am I?" were completed twice over an 8-week period by a volunteer sample of older persons (N = 104; age range: 69-92 years, M = 79). Low temporal stability of self-definition was found on an intraindividual level and on the level of interindividual differences. Measures of personality showed high stability. Although the "Who am I?" may not be the best instrument for assessing the content aspects of self-definition that are stable over time and across situations, it may provide a measure of situation-related variability.

Aged↗
PubMedDate not supplied

Performance characteristics of the button personal inhalable aerosol sampler.

The button inhalable aerosol sampler with a curved porous inlet recently was developed and evaluated as a stationary sampler in the laboratory and in the field. The present study focused on investigating its suitability for personal inhalable aerosol sampling. The button sampler was tested at two wind velocities (0.5 and 2.0 m/sec), three particle sizes (7, 29, and 70 microm) and three orientations to the wind (0, 90, and 180 degrees). The performance characteristics of the button sampler were compared with those of three other personal samplers--the IOM (Institute of Occupational Medicine), GSP, and 37-mm closed-face filter cassette. The experiments were conducted in a wind tunnel with the samplers mounted on a full-size manikin. The direction-specific sampling efficiency of the button sampler was found to be essentially independent of the wind direction and dependent on the wind velocity to a much smaller degree than that of the three other samplers. When direction-averaged, the fit of its sampling efficiency curve to the inhalability curve was found to be better than that of the 37-mm closed-face cassette, comparable with that of the GSP sampler, and less than that of the IOM sampler. The precision of the button sampler was found to be generally equal to or better than the precision of the comparison samplers. It was concluded that the button sampler can be successfully used as a personal inhalable aerosol sampler.

Aerosols↗
PubMedDate not supplied

Integration of physical medicine and rehabilitation into a medical school curriculum: musculoskeletal evaluation and rehabilitation.

The issue of increasing awareness of the specialty of physical medicine and rehabilitation is a primary concern of physiatrists in both teaching hospitals and private practice. Over the years, exposure to this specialty in medical schools has decreased, although there is simultaneously an increasing awareness of the importance of providing adequate musculoskeletal education for medical students. The authors describe one institution's success at integrating musculoskeletal medicine education, along with exposure to patients with chronic disease and disability. Curriculum content and a unique musculoskeletal skills acquisition test are discussed. Increased exposure to the specialty of physical medicine and rehabilitation in medical school can introduce numerous benefits for both the specialty and musculoskeletal education as a whole.

Clinical Clerkship↗
PubMedDate not supplied

Rating the burn scar.

A reliable, objective, and universal method of assessing burn scars does not exist in today's burn literature. Such a method is necessary to provide a descriptive terminology for the comparison of burn scars and the results of treatment. The method should be applicable to patients both within an institution and between burn centers. A burn scar assessment has been devised based on physical parameters. These relate to the healing and maturation of wounds, cosmetic appearance, and the function of the healed skin. Pigmentation, vascularity, pliability, and scar height are assessed independently, with increasing score being assigned to the greater pathologic condition. Normal skin has a score of 0. Seventy-three patients were assessed by three separate occupational therapists and the findings subjected to statistical analysis for interrater reliability. For each parameter a Cohen's kappa statistic of approximately 0.5 +/- 0.1 indicates a statistically significant agreement between observers. These values were found to improve with time. This appears to be a useful tool for the assessment of burn scars, allowing objective comparison of the same scar by different observers.

Adolescent↗
PubMedDate not supplied

Investigation of the presence and role of calmodulin and other mitogens in human burn blister fluid.

It is unclear whether burn blister fluid is beneficial or deleterious to the healing of the underlying wound. We investigated the calcium binding protein calmodulin in human burn blister fluid and its role in the mitogenicity of this fluid in the culture of human keratinocytes, fibroblasts, and mouse 3T3 fibroblasts. Calmodulin levels in blister fluid were three times greater than in serum (p < 0.005), whereas epidermal growth factor and platelet-derived growth factor concentrations were significantly lower (p < 0.001). Calmodulin in blister fluid was biochemically identified after affinity chromatography, Western blotting, and immunostaining with a monoclonal antibody. Inhibiting calmodulin with either an antagonist or antibody to calmodulin reduced the mitogenic activity of blister fluid in three cell types by 26% to 80%. These in vitro studies suggest that burn blister fluid may promote wound healing, and locally released calmodulin contributes to this effect. In appropriate cases it may be beneficial to leave burn blisters intact.

3T3 Cells↗
PubMedDate not supplied

Laboratory and hospital testing of new infrared tympanic thermometers.

A patented approach to infrared thermometry based on the use of a standard pyrosensor has resulted in the development of two new infrared tympanic thermometers, one for professional use, the other for home use. Both were tested to evaluate accuracy in the laboratory and to evaluate equivalence to standards, correlation to standards, and precision in human subjects. Accuracy was found to be well within ASTM standards on both models. Mean ear temperatures were 0.2 degrees C below oral and 0.7 degrees C below bladder temperature. Correlations between ear and oral and ear and bladder temperatures were r = .77 to .84. Repeatability in the same ear was very high at r = .95 (left) and .97 (right). Reproducibility between left and right ear ranged from r = .89 to .92.

Equipment Design↗