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Biomedical subjects

W A Phillips

Publications and source records attributed to W A Phillips.

At least 91 records · Page 5Linked to original sources
PubMed1988

Visual event perception in alcoholics.

A series of microcomputer-based procedures were devised to investigate the ability of alcoholics to detect and locate rapid visual changes, and to assess deficits of visual processing in this patient population. Forty alcoholics were tested 7-13 days after cessation of drinking (mean period of abstinence = 9.5 days), and 24 were retested 2-3 weeks later (mean abstinence = 27.8 days). In comparison to a matched control group the alcoholics were impaired on initial testing at locating visual events. Alcoholics also had significantly slower movement times in a visual-choice reaction time task, and were slower on visual search. At retest the alcoholics were impaired on one of the event perception tasks. Alcoholics were not impaired initially on a measure of visual memory span but were impaired at retest, possibly due to a learning deficit. It is concluded that alcoholics show a persisting deficit in the ability to notice and locate rapid visual changes, together with a transitory impairment on timed tasks requiring visually guided movement.

Adult↗
PubMed1988

Wisconsin and other instrumentation for posterior spinal fusion.

In idiopathic scoliosis, the Wisconsin system is as safe as a Harrington rod and nearly as strong as a Luque construct. The installation is relatively easy. Sagittal curves can be preserved while correcting the scoliosis by contouring the rods and fixing them to the spine in a segmental fashion. The Wisconsin system is currently the instrumentation of choice at the authors' clinic for routine idiopathic scoliosis. The quest for the ideal spinal instrumentation system will probably never end. Further improvements on the current systems will inevitably appear, and new concepts will be developed. Spine surgeons will continue to be faced with the need to compare the advantages and disadvantages of different systems.

Equipment Design↗
PubMed1988

Control of blood loss during scoliosis surgery.

By combining surgical and anesthetic techniques that minimize blood loss with the use of autotransfusion, it should now be possible to complete a routine posterior spinal fusion without using allogeneic blood transfusions. Surgical efforts should include careful preoperative planning, positioning with the abdomen hanging free, use of topical hemostatic agents, and decortication late in the procedure. Preoperatively donated autogeneic blood or reclaimed red cells from suction can take the place of allogeneic transfusions. Blood loss during scoliosis surgery correlates closely with left ventricular stroke work index (LVSWI), a measure of blood flow calculated from systemic vascular resistance, cardiac output, and heart rate. All of these parameters are under the anesthesiologist's control, making him the primary determinant of blood loss in scoliosis surgery. Induced hypotensive anesthesia may be ineffective in controlling blood loss if the cardiac output or heart rate is high. Halothane, a commonly used hypotensive agent, is not very useful for scoliosis surgery because spinal cord monitoring and wake-up testing are not possible. Rebound hypertension has been noted with the use of sodium nitroprusside. Trimethaphan works well clinically but experimentally it reduces spinal cord blood flow, which may increase the risk of spinal cord injury.

Anesthesia↗
PubMed1987

Priming of neutrophils and macrophages for enhanced release of superoxide anion by the calcium ionophore ionomycin. Implications for regulation of the respiratory burst.

Phagocytic cells can be primed for enhanced stimulated release of superoxide anion (O2-) by exposure to a variety of biologic agents, including gamma-interferon and lipopolysaccharide. We examined the role of calcium ion in this priming, using the calcium ionophore ionomycin. Preincubation with ionomycin, 1 to 10 nM, primed human neutrophils to release up to 7-fold more O2- during stimulation with 1 microM formyl-methionyl-leucyl-phenylalanine (f-Met-Leu-Phe). With 160 nM phorbol myristate acetate as stimulus, ionomycin caused a doubling of O2- production in mouse peritoneal macrophages. Incubation of phagocytes with ionomycin at priming concentrations did not directly stimulate O2- release. Priming of neutrophils occurred in 1-2 min and was associated with a marked reduction in the lag time for O2- release after f-Met-Leu-Phe stimulation and with an increase in the rate of O2- production. Kinetic analysis of NADPH-dependent O2(-)-producing activity in sonicates of resting human neutrophils incubated with sodium dodecyl sulfate suggested that modification of the enzyme responsible for the respiratory burst was not responsible for priming. Priming of neutrophils with ionomycin had no apparent effect on either the activity or subcellular distribution of protein kinase C. The effect of ionomycin on the cytosolic free calcium concentration ([Ca2+]c) was assessed in neutrophils using the calcium-sensitive fluorescent dye fura-2. Ionomycin at priming concentrations caused an approximate doubling of the base-line [Ca2+]c. When neutrophils were exposed to various concentrations of ionomycin, a parallel rise in [Ca2+]c and priming was observed. A rise in [Ca2+]c of approximately 0.8 microM caused half-maximal priming. These results suggest that an increase in [Ca2+]c is not sufficient to initiate release of O2-, but they support the concept that Ca2+ can serve as a second messenger in this event.

Animals↗
PubMed1987

The child with a limp.

The child with a limp is a commonly encountered diagnostic challenge. This article discusses normal gait in children and how to assess the limping child. A review of potential catastrophies and a differential diagnosis based on age is presented.

Adolescent↗
PubMed1986

Changes in the incorporation of free fatty acids upon the stimulation of human polymorphonuclear leukocytes.

We have investigated the incorporation of free fatty acids into the cellular lipids of human polymorphonuclear leukocytes (PMN). Resting PMN incorporated both saturated and unsaturated fatty acids into triacylglycerol with only small amounts incorporated into the phospholipids. In contrast, PMN stimulated with the calcium ionophore A23187 incorporated significantly higher amounts of fatty acids, predominantly those other than arachidonic acid, into phosphatidylcholine and phosphatidylinositol, with reduced incorporation into triacylglycerol. Stimulation of PMN with serum-treated zymosan or the chemotactic peptide f-met-leu-phe but not phorbol myristate acetate, also increased the incorporation of fatty acids into these phospholipids. This stimulation-induced incorporation of fatty acids into cellular phospholipids was directed exlusively into position 2 of the lipid and probably reflects the reacylation of lysophospholipids after the release of arachidonic acid by phospholipase A2.

Acylation↗
PubMed1986

Objective benefit of nifedipine in the treatment of Raynaud's phenomenon. Double-blind controlled study.

To compare the effects of the calcium channel antagonist, nifedipine, with that of placebo, a randomized double-blind crossover study was performed in 11 patients with moderate to severe Raynaud's phenomenon. Digital skin temperature recovery time was measured after immersing the patient's hand in ice water for 20 seconds. Patients were randomly assigned to receiving either nifedipine or placebo for one week, followed by the crossover phase. Skin temperature recovery time was also measured in 21 normal volunteers. The mean time to recovery for patients taking nifedipine was 28.5 +/- 20.8 minutes versus 44.9 +/- 18.9 minutes for patients receiving placebo (p less than 0.05 by analysis of variance with repeated measures). The mean time to recovery for the normal volunteers was 11.3 +/- 7.2 minutes versus 40.2 +/- 19.9 minutes for the patients (p less than 0.01 by the Student t test). Nine of the 11 patients noted improvement of symptoms during treatment with nifedipine. It is concluded that nifedipine is an effective, well-tolerated treatment for Raynaud's phenomenon.

Adult↗
PubMed1986

MRI and CT evaluation of primary bone and soft-tissue tumors.

Twenty-six patients with primary tumors of bone or somatic soft tissues underwent both magnetic resonance imaging (MRI) and computed tomography (CT); 15 of the patients had radionuclide bone scans as well. Only in a minority of cases did these tomographic methods provide information needed for diagnosis that could not be derived from the plain radiographs alone; however, for assessing the extent of the disease, both CT and MRI proved very valuable, particularly MRI. Specifically, MRI was superior to CT in delineating the extent of the neoplasms and their relation to surrounding structures in 21 of the patients, equal in four, and inferior in only one. Furthermore, in the 13 patients with tumors of long bone, MRI was judged superior to CT in visualizing marrow abnormality in 12 cases, and equal in only one case. Radionuclide scans demonstrated the lesions in 14 of the 15 cases; its primary utility was in excluding additional lesions. It is concluded that for these patients, MRI was the imaging method of choice in assessing the extent of bone and soft-tissue tumors.

Adolescent↗
PubMed1986

The effect of a preassembly zeranol implant and post-transit diet on the health performance and metabolic profile of feeder calves.

A total 262 Angus steer calves averaging 207 kg from none (trial 1) and five farms (trial 2) were identified on the farm of origin and one-half of the calves on each farm was implanted with 36 mg of zeranol before entering the feeder calf assembly and marketing system. Calves were assembled, fasted for 24 h and fed hay for 72 h, then shipped 1,368 km. Upon arrival, the following receiving diets were fed for 4 wk to one-third of the calves from each farm and implant group: 1) control diet, 2) high-potassium diet, 3) escape-protein diet using corn gluten meal, which can escape ruminal degradation as a protein source. Implanted calves gained more weight (P less than .10) than nonimplanted calves while on the farm, but changes in weight during assembly, transit and the 28-d receiving period were not different (P more than .10). Plasma glucose and total protein concentrations were higher (P less than .05), while urea nitrogen concentration was lower (P less than .05) for implanted calves following transit. Increasing the potassium concentration of the receiving diet increased (P less than .05) post-transit weight gains, but had no affect on dry matter consumption. Corn gluten meal replaced soybean meal in the escape-protein diet and resulted in similar weight gains. Plasma urea nitrogen concentrations were higher (P less than .05) at 2 wk post-transit in the escape-protein diet group as compared with the control group. Receiving diet had no effect on the incidence or severity of bovine respiratory disease, but affected (P less than .05) performance during the subsequent 69-d stocker phase of ad libitum access to medium quality hay and 2.27 kg of supplement per day.

Animal Feed↗
PubMed1986

The effect of pre-fast diet and transport on nitrogen metabolism of calves.

Two trials were conducted to determine the effects of transport stress and pre-transport diet on N losses, blood chemistry and ruminal variables of steers. In each trial, 16 crossbred steers (261 kg avg weight) were assigned to four groups in a 2 X 2 factorial arrangement of treatments. Treatments consisted of either transported or non-transported groups and two pre-transport dietary regimens (alfalfa hay or a 50% concentrate diet fed for 3 d before fasting). The alfalfa hay contained 14.6% crude protein (CP) and had a calculated metabolizable energy (ME) content of 1.92 mcal/kg. The 50% concentrate diet contained 15.5% CP and had a calculated ME content of 2.23 mcal/kg. Steers in the transport group were transported for 13 h in trial 1 and 46 h in trial 2, while the remaining steers were not transported. Both groups were withheld from feed and water during the observation periods. Urine and feces were collected and blood samples were obtained at intervals during the observation periods. Transport increased (P less than .05) urinary and total N excretion and nonevaporative water losses compared with fasting alone. Calves fed the 50% concentrate diet had lower N and nonevaporative water losses than calves fed hay, probably due to lower pre-fast N and water intakes. Ruminal total volatile fatty acid (VFA) concentrations and molar proportions of propionate and butyrate declined (P less than .05) with time in all groups, while molar proportions of acetate and minor VFA increased. Results of these trials indicate transportation stress can cause a significant increase in total N excretion and nonevaporative water loss compared with feed and water deprivation alone. Losses of N and water were lower in calves fed a 50% concentrate diet rather than hay for 3 d before the fasting period, probably because of lower pre-fast N and water intakes.

Animals↗
PubMed1985

A prospective, randomized study of the management of severe ankle fractures.

One hundred and thirty-eight patients with a closed grade-4 supination-external rotation or pronation-external rotation ankle fracture (Lauge-Hansen classification) who were seen in the emergency room of the University of Chicago Hospitals were entered into a randomized study of the results of various methods of treatment. Ninety-six patients with satisfactory initial closed reduction were randomized between continued closed treatment in a plaster cast and open reduction with rigid internal fixation according to the techniques of the Association for the Study of Internal Fixation (ASIF). Forty-two patients with unsatisfactory closed reduction were randomized between open reduction with internal fixation of only the medial malleolus and open reduction with rigid internal fixation according to the ASIF techniques. Of the 138 patients who were admitted to the study, only seventy-one (51 per cent) could be followed for an average of 3.5 years (a typical return rate of urban trauma centers). The outcomes were evaluated by a scoring system that included clinical, anatomical, and arthritis scores. Statistical analysis of the data showed that, of the patients with initial satisfactory closed reduction, the ones treated by open reduction and rigid internal fixation had significantly higher total scores, particularly the patients who were more than fifty years old and those with a medial malleolar fracture. The small number of patients with unsatisfactory closed reduction who were treated by one of the two types of open reduction and internal fixation and were available for follow-up precluded drawing any conclusions about the superiority of one method of internal fixation over the other in that group. The difference in the talocrural angle between the injured and normal sides was the only statistically significant radiographic indicator of a good prognosis.

Adolescent↗
PubMed1985

Comparative effects of khellin and timefurone on serum parameters in normal male cynomolgus monkeys.

Timefurone and khellin (10 mg/kg/day, gavage, 14 days) significantly lowered low density lipoprotein cholesterol, high density lipoprotein cholesterol, and total cholesterol. Khellin-induced changes were significantly greater than those induced by timefurone. Neither drug altered body weights or clinical chemistry parameters. Monkeys treated with khellin, however, exhibited elevated levels of very low density lipoprotein cholesterol and marked emesis, while no changes were observed with timefurone. On the basis of these data, timefurone has a better therapeutic ratio and further study with this promising drug appears warranted.

Animals↗
PubMed1984

Pregnancy and aggressive or malignant primary bone tumors.

The authors performed a retrospective study of 33 patients to assess the effect of pregnancy on the behavior of primary bone malignancies, and to develop a strategy for pregnant women with such malignancies focusing on decisions concerning the fetus. This study indicates that pregnancy has no effect on the clinical behavior of bone sarcomas, and, therefore, there is no reason to perform an abortion because of their simultaneous occurrence. However, optimal treatment of the tumor may cause irreparable harm to the fetus. Three main medical factors need to be considered when the future of the fetus is being decided: (1) the trimester at the time of diagnosis; (2) the anatomic site of the tumor; and (3) the type and grade of the tumor, as it relates to the expected treatment of the tumor.

Adult↗