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S Ballard

Publications and source records attributed to S Ballard.

14 recordsLinked to original sources

Tracing blood units to their recipients: results of a two-centre study.

An important principle of the use of blood components is the ability to trace them from the donor to the recipient. This study set out to establish whether there was sufficient documentation in patient case notes to confirm the transfusion of blood components in a sample of computer blood bank records at two large teaching hospitals in UK. The criteria for verification of transfusion were taken from guidelines from the British Committee for Standards in Haematology (Transfusion Medicine 1999, 9, 227-238). The blood bank computer records indicated that 486 units of blood components were issued and not returned to the blood bank for 80 patients during a 2-month period. Of the 486 units, transfusion of 409 units (84%) was verified against patient notes, but 77 units (16%) could not be verified as received by the patient. The study showed that documentation of transfusions was variable. For example, written prescriptions were only found for 204 units (42%). These results have implications for 'lookback studies' involving blood transfusion. Further efforts are required to educate those involved in transfusing blood about the need for accurate documentation.

Blood Banks↗

The insulin-like growth factor type I receptor stimulates growth and suppresses apoptosis in prostatic stromal cells.

Stromal cells derived from benign prostatic hyperplasia synthesize and secrete measurable levels of insulin-like growth factor (IGF). Seventy-two-hour conditioned medium obtained from these cells contains IGF-II at levels ranging from 125-177 ng/mL.10(6) cells. IGF-I is almost undetectable. RT-PCR analysis has demonstrated that the genes for both the type I IGF receptor (IGF-IR) and the type II IGF receptor (IGF-IIR) are expressed by benign stromal cells in vitro. Competition binding analysis for IGF-I and IGF-II confirmed the existence of binding sites for both ligands with respective Kd and binding capacities of 4.9 x 10(-9) mol/L and 6.6 x 10(5) sites/cell and 4.7 x 10(-9) mol/L and 3.8 x 10(6) sites/cell. Under serum-free conditions, IGF-I and IGF-II at 500 ng/mL induce 80% and 113% increases in stromal cell density, respectively, over a 96-h period. Incubation with the IGF-IR-neutralizing antibody alpha IR3 (50 micrograms/mL) reduces the rate of stromal cell proliferation by approximately 60-80% even in the presence of stimulatory concentrations of IGFs. Camptothecin-induced apoptosis is inhibited by the addition of IGF-I and -II (500 ng/mL). alpha IR3 suppresses these survival signals and itself induces cell death in the prostatic stroma. The data suggest that IGF-IR is a pivotal molecule in prostatic stromal cell maintenance, and that specific antagonism may offer a novel means of controlling the fibromuscular expansion characteristic of benign prostatic hyperplasia.

Apoptosis↗

Cost benefit of emerging technology in localized carcinoma of the prostate.

PURPOSE: In a health care environment strongly concerned with cost containment, cost-benefit studies of new technology must include analyses of loco-regional tumor control, morbidity, impact on quality of life, and financial considerations. METHODS AND MATERIALS: This nonrandomized study analyzes 124 patients treated with three-dimensional conformal radiation therapy (3D CRT) and 153 with standard irradiation (SRT) between January 1992 and December 1995, for histologically proven adenocarcinoma of prostate, clinical Stage T1 or T2. Mean follow-up is 1.4 years. Three-dimensional CRT consisted of six or seven coplanar oblique and lateral and, in some patients, AP fields designed to treat the prostate with a 1 to 1.7 cm margin. SRT consisted of 120 degrees bilateral arc rotation. Total doses to prostate were 67 to 70 Gy when pelvic lymph nodes were irradiated or 68.4 to 73.8 Gy when prostatic volume only was treated; dose per fraction was 1.8 Gy. Patients were interviewed weekly for severity of 12 acute intestinal and urinary pelvic irradiation side effects (0 to 4+ grading). Time and effort for 3D RTP and daily treatment with 3D CRT and SRT were recorded. Dose-volume histograms (DVHs) were calculated for gross tumor volume, planning target volume, bladder, and rectum. Actual reimbursement to the hospital and university was determined for 41 3D CRT, 43 SRT, and 40 radical prostatectomy patients treated during the same period. RESULTS: Average treatment planning times (in minutes) were: 101 for 3D conformal therapy simulation, 66 for contouring of target volume and sensitive structures, 55 for virtual simulation, 39 for plan preparation and documentation, 65 for physical simulation, and 20 for approval of treatment plan. Daily mean treatment times were 19 min for 3D CRT with Cerrobend blocking, 16 with multileaf collimation, and 10 with bilateral arc rotation. Dosimetric analysis (DVHs) showed a reduction of 50% in volume of bladder or rectum receiving doses higher than 65 Gy. Acute side effects included dysuria, moderate difficulty in urinating, and nocturia in 25-39% of both SRT and CRT patients; loose stools or diarrhea in 5-12% of 3D CRT and 16-22% of SRT patients; moderate proctitis in 3% of 3D CRT and 12% of SRT patients (p = 0.01). Chemical disease-free survival (prostate-specific antigen < or =2 ng/ml) at 3 years was 90% with 3D CRT and 80% with SRT (p = 0.01). Average initial treatment reimbursements were $13,823 (3D CRT), $10,864 (SRT), and $12,250 (radical prostatectomy). Average total treatment reimbursement and projected cost of management of initial therapy failures per patients were $15,173, $16,264, and $16,405, respectively. CONCLUSIONS: Three-dimensional CRT irradiated less bladder and rectum volume than SRT; CRT initial reimbursement was 28% higher than SRT and 12% higher than radical prostatectomy. Because of projected better local tumor control, average total cost of treating a patient with 3D CRT or radical prostatectomy is equivalent to cost of SRT. Treatment morbidity was lower with 3D CRT. Our findings reflect an overall benefit with 3D CRT as a new promising technology in treatment of localized prostate cancer. Dose-escalation studies may enhance its efficacy and cost benefit.

Adenocarcinoma↗

The neurological basis of attention deficit hyperactivity disorder.

Attention deficit hyperactivity disorder (ADHD) is a serious disability with long-term consequences. At present the disorder is considered organic in pathology, particularly in regard to central nervous system functioning. This paper reviews research on ADHD. The role of neurochemical stimulation is discussed, and the signs of neurological deficits are explored. Nearly 600,000 young people in the United States receive medication daily for ADHD, and these drugs mimic brain neurotransmitters. The chemical action of these drugs and the cognitive, affective, and behavioral effects are discussed. Side effects and dosage levels are also examined. Basic behavior modification with ADHD children and how these techniques can be combined with effective drug treatment are elaborated.

Attention Deficit Disorder with Hyperactivity↗

Volume calculation by means of SPECT: analysis of imaging acquisition and processing factors.

To assess the effect of image acquisition and processing factors on the volume calculated from single photon emission computed tomography (SPECT) images, the authors evaluated technical factors including image matrix size, size of the region of interest (ROI), activity concentration in the region, amount of background subtraction, type of reconstruction filter, section thickness, and number of projections. They found that the percentage of background subtraction was the single most important factor affecting volume calculation. The smaller the volume, the greater the amount of background subtraction needed before the ROI is drawn. As an acceptable means to circumvent the varying percentage of background subtraction for different volumes, a calibration curve was constructed relating the true volume with the calculated volume for a fixed percentage of background subtraction. The use of a 128 X 128 acquisition matrix and zooming of the reconstructed images were necessary for accurate calculation of volumes smaller than 300 mL.

Humans↗

The pharmacokinetics, pharmacological responses and behavioral effects of acepromazine in the horse.

After intravenous (i.v.) injection, acepromazine was distributed widely in the horse (Vd = 6.6 litres/kg) and bound extensively (greater than 99%) plasma proteins. Plasma levels of drug declined with an alpha half-life of 4.2 min, while the beta phase or elimination half-life was 184.8 min. At a dosage level of 0.3 mg/kg acepromazine was detectable in the plasma for 8 h post dosing. The whole blood partitioning of acepromazine was 46% in the plasma phase and 54% in the erythrocyte phase. Penile prolapse was clearly evident at doses from 0.01 mg/kg to 0.4 mg/kg i.v., and the duration and extent of protrusion were dose related. Hematocrit levels were significantly lowered by administration of 0.002 mg/kg i.v. (about 1 mg to a 500 kg horse) and increasing dosages resulted in greater than 20% lowering of the hematocrit from control levels. Pretreatment of horses with acepromazine also reduced the variable interval (VI 60) responding rate in all horses tested. These data show that hematocrit changes are the most sensitive pharmacological responses to acepromazine, followed by changes in penile extension, respiratory rate, VI responding and locomotor responses. Acepromazine is difficult to detect in plasma at normal clinical doses. However, because of its large volume of distribution, its urinary elimination is likely prolonged, and further work on its elimination in equine urine is required.

Acepromazine↗

Atypical conditions for quantitative recovery of acepromazine and chlorpromazine from plasma.

Recoveries of acepromazine and chlorpromazine from equine plasma were examined. Recoveries of both drugs from plasma were poor under theoretically optimal conditions for basic drugs. When a wide range of extraction pH was examined, it was found that more complete recoveries of these drugs from plasma were achieved at pH 5-6. Use of [3H] chlorpromazine showed that the rate of migration of the drug from an aqueous to a nonpolar environment was much faster at pH 6.0 than at pH 9.2 from both plasma and buffer solutions. Times required for equilibration with agitation were 15 min at pH 6.0, 1 h at pH 9.2, and 2 h at pH 11.0. With these agitation times and pH values, recoveries were more than 95% complete.

Acepromazine↗

Quantifying nursing needs in home health care.

A study was conducted to determine what factors were most predictive of the quantity of nursing service and total agency service required by cardiac and cancer patients in home-care agencies. A retrospective record review on 397 patients in 9 randomly selected Connecticut home-care agencies collected demographic data on referral and payment source, support system, discharge status, primary care provider, and health status, as well as total number of professional and nonprofessional visits and length of stay. The Health Status Score, which measured deficits in daily activities and nursing problems, proved to be the best predictor. The ability of the Health Status Score to predict the need for total agency visits was particularly strong for cancer patients. The agency variable was a significant predictor of resource utilization, especially for cardiac patients. A significant limitation of the study was the inconsistency among the agencies regarding closure of records. Future research into resource use in home care depends on consistent and complete recording practices across agencies.

Adolescent↗