Biomedical subjects
Publications and source records attributed to D Jackson.
The antiplasmin which migrates electrophoretically with the alpha(2) globulins preponderates in effect over that of the alpha(1) migrating antiplasmin. This preponderance persists at physiological pH value in vitro and the significance of this finding is discussed. No evidence has been obtained of the existence of anti-urokinase activity in antiplasmin-free serum fractions.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
This article reviews retrospective data derived from Sharp The BirthPlace. San Diego for 1993-94 and from the University of California. Irvine, Birthing Center for 1994 and compares these findings to data obtained from the National Birth Center Study (NBCS). The focus of this article is on intrapartum transfer rates from the two freestanding birth centers as a critical clinical indicator. Cause-specific transfer rates were calculated for eight clinical conditions. Data suggest that cause-specific intrapartum transfer rates are influenced by factors such as risk profile of the client population, distance to the referral center and mechanisms of transfer, definitions and diagnostic criteria used, and clinical practice guidelines. Reports from the literature, such as NBCS data, might serve as points of reference, but are likely not appropriate baseline indicators (benchmarks of "best practice") for clinical events, against which individual performance can be measured; rather, these benchmarks should be individually defined, based on characteristics unique to each birth center.
Several studies have investigated the effects of prenatal cocaine (PCOC) exposure on the nigrostriatal dopaminergic system in animal models of maternal drug abuse, yet independent examinations of striatal dopamine (DA) receptors and tissue DA levels have produced equivocal results. The current meta-analysis provides a quantitative review of the literature on these topics, and analyzes potential moderators of the effects of PCOC exposure on these variables. The results indicate that the effects of PCOC exposure on striatal DA levels, D1 and D2 receptor-binding densities, and D2 receptor-binding affinity are negligible when collapsed over age, sex, species, and several other methodological variables. However, effects of PCOC exposure on some dopaminergic measures were significantly influenced by factors such as age and sex. As expected, and as suggested by the selectivity and specificity of PCOC-induced changes reported in the published literature, the direction and magnitude of differences between genders or age groups in this study were not systematic across all dependent measures. Generally, PCOC exposure was more often linked to decreases, rather than increases, in the selected dependent measures. These findings indicate that PCOC exposure produces selective alterations in striatal dopaminergic system function which do not appear under all experimental circumstances, but which may be important factors in behavioral alterations seen in selected groups after PCOC exposure.
Two novel hypolipidaemic agents, both members of the aminopyrimidine series, with a mode of action of inhibition of oxidosqualene cyclase (OSC), were administered orally to dogs and mice for 14 and 28 days. Both compounds produced a similar spectrum of pathologic changes. In dogs, the agents produced equatorial single cell necrosis and cataract in the lens (also observed clinically); atrophy, ulceration, and inflammation of the cornea; hyperkeratosis, acanthosis, hair papillary atrophy, and inflammation of the skin; and epithelial degeneration and sperm granuloma in the epididymides. One female dog showed signs of liver toxicity. In mice, severe cataract formation was seen with both compounds, and liver toxicity was produced by one of the compounds. The severity and speed of onset of the cataract formation were very marked. The changes seen were dissimilar to those reported with the most commonly used class of hypolipidaemic agents in the clinic, the hydroxymethyl glutaryl coenzyme A (HMGCoA) reductase inhibitors but were reminiscent of those reported for the hypolipidaemic agent Triparanol. which was predictive of toxicity seen in man.
One-third of the adolescent patients followed up in our prosthetic clinic have developed patellar dislocation. Four cases are described, and radiographs are evaluated for femoral-tibial alignment, patellar height, and tibial length. Patella alta was present in each patient. We propose that the forces associated with the patellar tendon-bearing prosthesis may produce elongation of the patellar tendon in young patients and predispose them to patellar instability.
BACKGROUND: The purpose of this study was to determine precipitation limits and construct curves for calcium and phosphorus in parenteral nutrition solutions compounded with specialty amino acid solutions. METHODS: The effect of temperature, concentration of amino acids, and pH on the solubility of calcium and phosphate was studied for two specialized amino acid solutions: NephrAmine and HepatAmine. Ten amino acid solutions were manufactured with NephrAmine and 12 with HepatAmine at amino acid concentrations of 0.8%, 1.5%, and 2%. The final dextrose concentration was 10%. Some of the solutions were tested with the additive cysteine hydrochloride, 40 mg cysteine/g of protein, and some were buffered with sodium bicarbonate or hydrochloric acid to model the pH of a combined fat emulsion and total parenteral nutrient (TPN) solution. Calcium gluconate and potassium phosphate were added to test samples of each TPN solution. A range of calcium concentrations of 2.5 to 40 mEq/L and phosphate concentrations of 2.5 to 40 mmol/L were tested. After storage at room temperature (25 degrees C) for 18 hours, solutions were inspected for precipitation. At the end of the 18-hour period, the solutions were held in a water bath at 37 degrees C for 30 minutes and inspected for precipitation and microcrystallization. RESULTS: Solubility curves were plotted to represent Ca-PO4 solubility limits before visual or microscopic precipitation. These curves depend on the variables of time, temperature, concentration, and pH. CONCLUSIONS: These data and graphs will help the clinical pharmacist estimate Ca-PO4 solubility limits and prevent precipitation of TPN solutions formulated with NephrAmine or Hepatamine.
BACKGROUND: The purpose of this study was to evaluate the feasibility and safety of early enteral feedings of critically ill pediatric patients. METHODS: The subject population of 42 critically ill patients ranged in age from 5 days to 18 years (mean 5.8 years), mean weight 17 kg. Transpyloric nasoenteric tubes were placed in all patients by a nonfluoroscopic bedside technique. All subjects were mechanically ventilated; 32 (76%) were on one or more vasoactive medications. Six (15%) patients were fed for more than 13 days while on vasoactive support and pharmacological paralysis. RESULTS: There were no documented complications of early enteral feeding, including aspiration. All patients were able to achieve caloric goals within 48 hours of beginning enteral feedings. All patients developed regular stool patterns despite periodic absence of bowel sounds. Enteral feedings replaced 256 days of total parenteral nutrition. Estimated patient charge savings averaged $425 for each day of enteral feedings. CONCLUSIONS: Early enteral feedings are feasible, well tolerated, and cost effective in critically ill pediatric patients.
BACKGROUND: The purpose of this study was to demonstrate the feasibility of placing transpyloric feeding tubes at the bedside without fluoroscopy in critically ill pediatric patients. METHODS: The patient population consisted of 90 patients (ages 1 week to 15 years, median age 9 months) admitted to a 26-bed pediatric intensive care unit in a university-affiliated pediatric hospital. Patient weights ranged from 2.4 to 100 kg with a median weight of 7.5 kg. Seventy-six patients were endotracheally intubated and mechanically ventilated; one patient had a tracheotomy. A total of 24 patients were pharmacologically paralyzed; 38 patients were receiving catecholamine infusions, and 17 patients had intracranial monitoring devices in place. All had concurrent nasogastric suctioning. Nonweighted Silicone Rubber 6F or 8F nasoenteric tubes were inserted at the bedside using metoclopramide, air insufflation and positioning to achieve transpyloric passage. Blue-dyed water was instilled in 58 patients to test for reflux and confirm transpyloric position. RESULTS: Successful nonfluoroscopic bedside transpyloric (duodenal or jejunal) tube placement was verified radiographically in 84 (93%) patients; seven of these patients were less than 4 weeks of age. One patient had blue dye in the nasogastric fluids, consistent with duodenogastric reflux or failure of transpyloric passage. The abdominal radiographs confirmed the results of the blue dye test in all 58 patients. There were six (6.7%) unsuccessful attempts at transpyloric bedside tube placement: four were a result of hemodynamic instability, one was a result of oropharyngeal trauma, and one was due to intestinal malrotation. The average time for placement was 15 minutes with a range of 5 to 45 minutes. No complications from tube placement were observed. CONCLUSIONS: Bedside placement of transpyloric feeding tubes is a safe and effective method to institute enteral feedings in critically ill pediatric patients.
A bolus of 3 mg. of atropine was given intravenously (I.V.) TO 123 ANESTHETIZED PATIENTS. Increases in heart rate were seen in 109 patients (88 percent), while 7 patients (5.7 percent) had no change. A mean increase in systolic arterial blood pressure of 14 mm. Hg was noted. A certain pattern in increases in heart rate and systolic blood pressure was observed. Ninety-six percent of the patients under cyclopropane, fluroxene, ether, ketamine, or regional (spinal or epidural) anesthesia had heart-rate increases, compared with only 77 to 89 percent of the patients anesthetized with halothane, enflurane, or neuroleptanalgesics. Rise in systolic blood pressure was seen in 40 to 50 percent of the former, but only in 31 to 40 percent of the latter group. The arrhythmias observed were transient A-V junctional tachycardias in three instances and bigeminal rhythm in one patient under cyclopropane anesthesia, The administration of a vagolytic dose of atropine to anesthetized patients appears not to be as arrhythmogenic as previously considered.
Explore the source record for details and available documents.
This qualitative study was undertaken to explore the relevance and meaning of the experience of hope for survivors of acute myocardial infarction (AMI). Depth interviews were conducted with eight survivors (n = 8) of AMI at four weeks following discharge from hospital. Analysis of transcribed interviews revealed three distinct narrative themes. These were holding on to human connectedness, finding and harnessing the 'will' to live, and, having faith in the primacy of a higher power. Study findings are discussed in relation to the literature. Findings of the study assist in building knowledge and understanding of the complex phenomenon of hope. Implications for nursing practice and research are drawn from study findings.
Explore the source record for details and available documents.
The 1999/2000 winter demands on the NHS have once again highlighted deficits in UK critical care provision (Daily Telegraph, 2000; London Evening Standard, 2000) Recent years have seen the development of the role of health care support workers in the NHS; some critical care units now employ health care support workers This research examined the views of critical care unit staff on the introduction of health care support workers into the critical care unit It is concluded that the role is viable within the setting of this study A framework is outlined that could form the basis for a critical care health care support worker training programme