Raised intraabdominal pressure, renal failure, and the bumble bee.
Explore the source record for details and available documents.
Acute Kidney Injury↗
Biomedical subjects
M Fisher
Publications and source records attributed to M Fisher.
Sonographic pseudokidney after nephrectomy.
When interpreting renal sonograms, one should be aware of the possibility of mistaking fat and scarring in the renal fossa for a normal kidney in a patient with a history of prior nephrectomy. When in doubt, the ultrasound findings should be confirmed with a CT scan.
Adipose Tissue↗
Composition of whole unstimulated saliva of healthy children: changes with age.
Whole unstimulated saliva was collected from 136 healthy subjects divided into 5 groups according to age: (1) 25 infants, 7-11 months old; (2) 28 toddlers, 2-3 yr old; (3) 28 children, 6-8 yr old; (4) 28 adolescents, 12-14 yr old; (5) 27 adults, 25-63 yr old. The concentrations of Na, K, total protein, IgA and amylase activity were measured. A significant ascending linear correlation with age was found for concentrations of Na, total protein, IgA and amylase activity. There were significant differences between age groups in K and IgA concentrations. Salivary amylase activity was very variable, and a significant difference was found between infants and toddlers only. Salivary composition thus changes significantly during childhood, implying a process of development and maturation of the salivary glands and indicating the need of age-matched controls for the clinical use of saliva.
Adolescent↗
Algorithms for the computation of spatial statistics.
Algorithms are described for the calculation of spatial statistics. The statistics are the functions K(t), G(y), F(x), and K12(t). They can be used to determine (a) which type of spatial process ('random', 'clustered', 'regular', etc.) best fits a data set and whether the spatial pattern changes with distance, and (b) whether two types of events are correlated with each other, and if so, at which distances the correlation occurs. These functions provide a powerful tool for analysing the spatial distribution of biomedical and biological phenomena. An interactive, command-driven program that incorporates these algorithms is described.
Algorithms↗
Hermansky-Pudlak syndrome: case report and clinicopathologic review.
The Hermansky-Pudlak syndrome is an autosomal recessive disorder consisting of the triad of albinism, a bleeding diathesis, and ceroid deposition within the reticuloendothelial system. In this study of a patient with Hermansky-Pudlak syndrome, we demonstrate the presence of ceroid within dermal macrophages. Electron microscopic studies suggest that melanosomes may be a substrate for the formation of ceroid in the skin. A review of the clinical and pathophysiologic features of this disorder is presented.
Albinism↗
Adolescent medicine in pediatric practice.
Adolescents report important unmet health care needs. This study directly assesses pediatricians' current practices pertinent to the primary care of adolescents. An anonymous questionnaire survey of general pediatricians was conducted in two suburban counties in New York State. Of the 101 respondents, 51% were older than age 50 and 88% were in private practice. The "average" pediatrician saw 28 patients in a 7-hour office day. Approximately 1 in 10 regularly saw patients with a sexuality-related concern, substance abuse problem, or anorexia nervosa. Fewer than half provided anticipatory guidance regarding sexuality, and only 14% questioned teens about depression. Respondents perceived factors related to fees, lack of time, lack of knowledge, and their image as obstacles to an expanded care of adolescents. Those with some training in adolescent medicine during residency were significantly more likely to provide care and anticipatory guidance related to sexuality and substance abuse. Thirty percent reported an interest in increasing their involvement with adolescents. We conclude that most of these pediatricians played a small role in meeting the health needs of adolescents.
Adolescent↗
Dietary n-3 fatty acid supplementation reduces superoxide production and chemiluminescence in a monocyte-enriched preparation of leukocytes.
Consuming substantial quantities of n-3 fatty acids reduces atherogenesis in experimental models of atherosclerosis. The mechanisms of this beneficial effect remain uncertain. Monocyte-derived tissue macrophages are associated with atherogenesis, and inhibition of monocyte inflammatory activity could, hypothetically, be helpful in preventing atherosclerosis. We observed that stimulated human monocyte and/or macrophage production of superoxide and the occurrence of monocyte chemiluminescence, two indices of monocyte inflammatory activity, were significantly reduced by the ingestion of 6 g n-3 fatty acids/d for 6 wk. This effect was associated with a reduction of stearic and arachidonic acids whereas eicosapentaenoic and docosahexaenoic acid concentrations rose significantly. These results indicate that modest dietary n-3 fatty acid supplementation can reduce stimulated human-monocyte free-radical production and may impair the capability of macrophages derived from monocytes to promote oxidation of low-density-lipoprotein cholesterol and associated cellular toxicity.
Adult↗
Impairment of theophylline clearance by a hypocaloric low-protein diet in chronic obstructive pulmonary disease.
The effect of a hypocaloric, low protein diet on theophylline kinetics was studied in a 70-year-old man with chronic obstructive pulmonary disease who lost 6.2 kg of weight. Total systemic clearance, unbound clearance, and intrinsic hepatic clearance fell dramatically. Theophylline elimination half-life rose from 8.4 to 17.1 h. Therefore, a diet deficient in both calories and protein can significantly impair theophylline clearance and prolong theophylline elimination half-life.
Aged↗
The free amino acid profile in the middle gluteal before and after fatiguing exercise in the horse.
Explore the source record for details and available documents.
Amino Acids↗
Human lower esophageal sphincter pressure response to increased intra-abdominal pressure.
We studied the effects of increased intra-abdominal pressure on the lower esophageal sphincter (LES) pressure in 15 healthy subjects. The role of the diaphragm in the genesis of LES pressure during increased intra-abdominal pressure was determined by measuring diaphragm electromyogram (EMG). The latter was recorded using bipolar intraesophageal platinum electrodes that were placed on the nonpressure sensing surface of the sleeve device. We also measured the LES pressure response to increased intra-abdominal pressure during inhibition of the smooth muscles of the LES by intravenous atropine (12 micrograms/kg). Straight-leg raising and abdominal compression were used to increase intra-abdominal pressure. Our results show that the increase in LES pressure during straight-leg raising is greater than the increase in gastric pressure. During abdominal compression, the rate of LES pressure increase is faster than that of the gastric pressure, suggesting an active contraction at the esophagogastric junction. The increase in LES pressure during periods of increased intra-abdominal pressure is associated with a tonic contraction of the crural diaphragm as demonstrated by EMG recording. Atropine inhibited the resting LES pressure by 50-70% in each subject but had no effect either on the peak LES pressure attained during increased intra-abdominal pressure or tonic crural diaphragm EMG. We conclude that 1) there is an active contraction at the esophagogastric junction during periods of increased intra-abdominal pressure and 2) tonic contraction of the crural diaphragm is a mechanism for this LES pressure response.
Abdomen↗
A 21-aminosteroid reduces hydrogen peroxide generation by and chemiluminescence of stimulated human leukocytes.
Leukocytes recruited to regions of focal cerebral ischemia may contribute to tissue injury by their ability to promote inflammation. A novel group of drugs, the 21-aminosteroids, have been observed to reduce neurologic damage and vasogenic cerebral edema in animal models of stroke by inhibiting lipid peroxidation. Production of hydrogen peroxide and free radicals by leukocytes during the inflammatory response may contribute to lipid peroxidation and other consequences of free radical-mediated tissue injury. We assessed the effect of U74500A, a 21-aminosteroid, on the generation of hydrogen peroxide by and on the chemiluminescence of stimulated polymorphonuclear leukocytes and monocytes from normal humans. U74500A significantly reduced the generation of hydrogen peroxide by polymorphonuclear leukocytes (p less than 0.001) and monocytes (p less than 0.01) in a dose-dependent manner. Monocyte chemiluminescence was also significantly inhibited (p less than 0.05), but polymorphonuclear leukocyte-associated chemiluminescence was unchanged. Our results indicate that U74500A can reduce the concentration of oxygen metabolites associated with stimulated human leukocytes, and this effect may explain in part how 21-aminosteroids reduce lipid peroxidation, ischemic injury, and vasogenic edema.
Adult↗
Correlates of middle cerebral artery blood velocity in the elderly.
We analyzed the association between hematologic factors and blood velocity of the middle cerebral artery in 42 healthy ambulatory subjects aged 63-86 years. We found a significant inverse association between mean velocity and both hematocrit (r = -0.37, p less than 0.02) and fibrinogen concentration (r = -0.42, p less than 0.005). These two variables are independently associated with velocity and together explain 29% of the variance in mean velocity. Both hematocrit and fibrinogen concentration should be considered in the interpretation of transcranial Doppler findings in this population.
Aged↗
Geometric factors of the bifurcation in carotid atherogenesis.
In vitro studies have demonstrated that geometry of the carotid bifurcation predicts blood flow alterations associated with atherosclerotic plaque formation. We investigated intraindividual asymmetry of carotid atherosclerosis by measuring geometric aspects of the carotid bifurcation. We measured diameter stenosis, the internal carotid artery/common carotid artery area ratio, and the angle of the carotid bifurcation on 40 arteriograms. Stenosis asymmetry was significantly associated with area ratio asymmetry (r = 0.355, p less than 0.025); there was no such association between stenosis asymmetry and bifurcation angle asymmetry. Geometric factors of the carotid bifurcation, particularly the area ratio, may help explain intraindividual asymmetry in carotid atherosclerosis.
Aged↗
Delayed treatment with a t-PA analogue and streptokinase in a rabbit embolic stroke model.
Fibrinolytic therapy may be effective in the treatment of ischemic stroke, and clinical trials are under way. We evaluated two fibrinolytic agents, an analogue of tissue plasminogen activator (Fb-Fb-CF, the catalytic fragment of the tissue plasminogen activator molecule with a prolonged serum half-life, n = 10) and streptokinase (n = 7), in a rabbit model of embolic stroke. Both agents were given 3 hours after stroke onset, a time relevant to the clinical setting. Fb-Fb-CF was significantly better (p less than 0.04) than saline (n = 7) in restoring blood flow to previously occluded intracranial arteries, but streptokinase was ineffective. Neither fibrinolytic agent was associated with a substantial risk for intracerebral hemorrhagic side effects. Our study demonstrates that Fb-Fb-CF can safely and effectively reperfuse rabbit intracranial arteries 3 hours after occlusion, while streptokinase does not.
Animals↗
Assessment of median nerve somatosensory evoked potentials in cerebral ischemia.
Seventy patients with cerebral ischemia (21 with transient ischemic attack and 49 with stroke) were studied with short-latency median nerve somatosensory evoked potentials to characterize the evoked potentials in all ischemic patients and to investigate their efficacy for prognosis in stroke. Within 72 hours of symptom onset, all 70 patients received a scaled neurologic function score, with a maximum of 50 points. Somatosensory evoked potential abnormalities were found in 10% (2/19), 42% (15/36), and 93% (14/15) of all patients with initial neurologic examinations who had normal (50 points), mild-moderate (30-49 points), and severe deficits (less than or equal to 29 points), respectively. Thirty-seven of the 49 stroke patients were available for a follow-up neurologic assessment. Eight-nine percent (8/9) of the stroke patients with poor outcome had somatosensory evoked potential abnormalities; 82% (9/11) of the stroke patients with severe neurologic deficits at onset had poor outcome. Results demonstrate that somatosensory evoked potential abnormalities are common in patients with cerebral ischemia but that somatosensory evoked potential findings are not significantly better than a detailed neurologic examination in predicting outcome from stroke.
Adult↗
Transient focal neurologic deficits complicating interleukin-2 therapy.
We report 2 patients with transient, focal, repetitive, stereotyped episodes of neurologic deficits during treatment with interleukin-2. One patient had recurrent monocular blindness, while the 2nd had recurrent homonymous quadrantanopia. We suggest that these attacks are provoked by endothelial cell activation induced by interleukin-2.
Blindness↗
Effect of sodium bicarbonate on racing Standardbreds.
Twenty-two Standardbred horses in race training were used in a crossover experiment to determine the effect of oral sodium bicarbonate (NaHCO3) administration on performance and metabolic responses to a 1.6-km (1-mile) race. Horses were paired and one horse in each pair was treated with either NaHCO3 (300 mg/kg BW) or a placebo, 2.5 h before they raced against each other. Each horse was scheduled to compete in two races, approximately 1 wk apart, one on each treatment. Horses always raced in the same pairs. Fourteen horses successfully completed both races. Jugular blood samples were obtained 1.5 h after treatment (rest), immediately before racing, 5 min post-race and 15 min post-race. In six horses, blood samples also were obtained 30 min post-race. Race times averaged 1.1 s faster after NaHCO3 treatment (P less than .1). Sodium bicarbonate treatment also elevated blood pH (P less than .05). In the horses sampled 15 and 30 min post-race, blood lactate disappearance was faster with the NaHCO3 treatment (P less than .05). The NaHCO3 may delay the fatigue precipitated by i.m. acidosis. Because other factors may limit performance (musculoskeletal soundness, cardiovascular and respiratory ability), NaHCO3 would not be expected to enhance the performance of all horses. However, the effect of NaHCO3 on lactate clearance may have implications for all intensively worked horses; because lactate and the associated hydrogen ions are believed to cause muscle damage and soreness, any mechanism to increase their removal rate could benefit the equine athlete.
Acid-Base Equilibrium↗
Chimeric analysis of the site of Lurcher gene action with respect to glial enzyme expression.
Immunocytochemical analysis of aggregation chimeras made using either of the mutants, Lurcher or Purkinje cell degeneration, previously showed that only Bergmann glia close to surviving Purkinje cells expressed an apparently normal level of the enzyme, glycerol-3-phosphate dehydrogenase (GPDH) (Fisher and Mullen, 1988). In the present study, aggregation chimeras were made using embryos from a B6D2 hybrid mouse strain carrying the Lurcher (Lc/+) mutation and homozygous for an allele specifying a high level of beta-glucuronidase activity and embryos from a wild-type C3H strain with low beta-glucuronidase activity. Chimeric cerebella were analyzed immunocytochemically and histochemically to determine whether Lurcher mutant Bergmann glia could express a normal, high level of GPDH. Comparisons between pairs of alternately stained, 2 microns thick serial sections showed that Bergmann glia with high level of beta-glucuronidase (i.e., Lurcher) expressed normal GPDH immunoreactivity only when close to surviving, wild-type Purkinje cells. Interestingly, in Purkinje cell-free areas of cerebellar cortex that were sufficiently large that GPDH expression was diminished, Bergmann glia also showed a reduced level of histochemically detectable beta-glucuronidase activity, as do Bergmann glia in adult Lc/+ mice. The results indicate that Lc/+ mutant Bergmann glia are not intrinsically defective with regard to expression of the enzymes, GPDH and beta-glucuronidase, but rather, expression of these enzymes depends on glial interaction with wild-type Purkinje cells.
Alleles↗