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D Leopold

Publications and source records attributed to D Leopold.

At least 19 recordsLinked to original sources
PubMed2000

Xenon-enhanced computed tomography quantifies normal maxillary sinus ventilation.

OBJECTIVE: The purpose of this study was to determine the applicability, safety, and normal parameters of a xenon-enhanced CT technique to quantify maxillary sinus ventilation. PATIENTS AND METHODS: Nine healthy subjects inhaled a xenon-oxygen-air mixture through their noses while repeated CT scans were performed through the same section of their sinuses. Images were obtained every 1 to 3 minutes and analyzed to measure the density of the gas in the maxillary sinus as a function of time. RESULTS: Individual nasal cavity time constants ranged from 0.5 to 18 minutes. Studies performed after decongestion showed poorer sinus ventilation. CONCLUSIONS: The xenon-CT washin/washout technique is safe, effective, and gives representative data.

Adult↗
PubMed2000

Gastric acid suppression does not promote clostridial diarrhoea in the elderly.

Gastric acid prevents bacterial colonization of the stomach and suppression of its secretion might predispose to Clostridium difficile (CD) diarrhoea. We retrospectively studied elderly patients admitted to medical wards of an acute hospital to determine whether the incidence of CD diarrhoea was greater among those previously treated with gastric acid suppressants. From records of stool CD toxin tests undertaken in 1995 and 1996, we found 126 cases with positive results, and selected 126 controls with negative results. Information about pre-morbid illness, predisposing factors for CD and medication received in the preceding 16 weeks was obtained from case-notes. A greater number of CD positive cases had received antibiotics such as Cefuroxime, ciprofloxacin or macrolides with or without metronidazole, were more severely disabled, required assistance for feeding, or had hypoalbuminaemia before the onset of diarrhoea. A greater number of controls had received lactulose, suggesting either that its laxative effect resembled CD infection prompting frequent stool tests, or that it offered protection against CD in this group. Both groups were similar for the use of proton-pump inhibitors or H2-receptor antagonists, suggesting that susceptible elderly patients are not more likely to develop CD diarrhoea after receiving gastric acid suppression therapy.

Activities of Daily Living↗
PubMed1997

Outcomes assessment.

Explore the source record for details and available documents.

Activities of Daily Living↗
PubMed1996

Fibronectin fibrils and growth factors stimulate anchorage-independent growth of a murine mammary carcinoma.

Stromal cells are important regulators of mammary carcinoma growth and metastasis. We have previously shown that a 3T3-L1 adipocyte cell line secretes hepatocyte growth factor (HGF), which stimulates proliferation of a murine mammary carcinoma (SP1) in monolayer cultures (DNA Cell Biol. 13, 1189-1897, 1994). We now examine the role of growth factors and the extracellular matrix protein fibronectin in stimulation of anchorage-independent growth of SP1 cells. Purified transforming growth factor-beta (TGF-beta) stimulated significant colony growth in soft agar cultures, whereas HGF had a lesser effect. Analysis by confocal microscopy revealed that carcinoma cell colonies contained extracellular microfibrils composed of fibronectin. Partial depletion of fibronectin from 7% FBS/agar cultures reduced the number of colonies; colony growth could be recovered by adding back exogenous fibronectin. Addition of the 70-kDa N-terminal fragment of fibronectin, which inhibits fibronectin fibril formation, reduced growth of SP1 cell colonies, but an 85-kDa fragment containing the cell binding domain did not inhibit colony growth. These findings indicate that deposition of extracellular fibronectin fibrils is necessary, but not sufficient, for anchorage-independent growth of SP1 mammary carcinoma cells; growth factors are also required. SP1 cells had less fibronectin mRNA and secreted less fibronectin protein under anchorage-independent conditions than under anchorage-dependent conditions, as determined by Northern blotting and immunoprecipitation analysis. Thus, both growth factors (HGF and TGF-beta) and fibronectin may be important regulators of paracrine stimulation by stromal cells of anchorage-independent growth of mammary carcinoma cells.

3T3 Cells↗
PubMed1996

Detection of the chemokine RANTES and endothelial adhesion molecules in nasal polyps.

BACKGROUND: To better understand the mechanisms of eosinophil recruitment into the upper airways, we examined human nasal polyps for the expression of the chemotactic cytokine RANTES and the endothelial adhesion molecules E-selectin and vascular cell adhesion molecule-1 (VCAM-1). METHODS: Routine histologic examination and immunostaining with antibodies to RANTES, E-selectin, and VCAM-1 were performed on three types of tissues: nasal polyps, sinus mucosa, or turbinates from patients undergoing other elective procedures (S/T), and nasal biopsy specimens from nonallergic volunteers (NA). To further quantify the expression of endothelial adhesion molecules, some tissue samples were homogenized, and the resulting supernatants were assayed with sandwich ELISAs for VCAM-1 and E-selectin. RESULTS: Polyp eosinophil counts ranged from 19/mm2 to 1818/mm2 (763 +/- 120/mm2, mean +/- SEM) and were significantly higher than those found in the control tissues (5 +/- 2 in S/T samples and 20 +/- 9 in NA samples, p < 0.002). Immunochemical staining for RANTES was observed in 11 of 14 polyps; intense staining for RANTES (grade 3) was observed in six of 14 polyps. None of nine S/T samples or five NA samples demonstrated grade 3 staining. Staining with anti-RANTES was largely localized to airway and glandular epithelium. There was no significant correlation between counts of eosinophils or the combined total of eosinophils plus mononuclear cells and the intensity of epithelial RANTES staining in all nasal tissues. Staining for VCAM-1, as well as for E-selectin, was detected in 11 of 14 polyps and eight of 13 control tissues. VCAM-1 detected by ELISA in polyp tissues (6.8 +/- 1.3 micrograms/gm) was higher than that found in six S/T samples (1.2 +/- 0.3 micrograms/gm, p < 0.005) and in two NA samples (1.8 +/- 0.02 micrograms/gm, p = 0.08). E-selectin values in polyps (1.4 +/- 0.3 micrograms/gm) were not statistically different from those detected in six S/T samples (0.5 +/- 0.2 microgram/gm) or two NA samples (1.6 +/- 0.4 microgram/gm). Counts of eosinophils and eosinophils plus mononuclear cells displayed a strong correlation with VCAM-1 ELISA values (p < 0.005 and p < 0.004, respectively) but not with VCAM-1 staining. VCAM-1 staining correlated with EG2-positive eosinophils in nasal polyp tissues (p < 0.01). E-selectin staining did not correlate with either neutrophil or eosinophil counts. CONCLUSIONS: These studies demonstrate that the chemokine RANTES is produced in vivo predominantly to nasal epithelium. Endothelial activation, as indicated by adhesion molecule expression, occurs in human nasal polyp tissues and in control tissues, possibly reflecting the continued antigen exposure of the nasal mucosa. The correlations found in this study suggest that expression of VCAM-1 plays a role in the selective recruitment of eosinophils and mononuclear cells into nasal polyp tissues and that RANTES may be more important in localizing eosinophils to the epithelium.

Adult↗
PubMed1996

A history of rhinology in North America.

The history of rhinology is the story of the efforts of men and women who have tried to help patients who have nasal and sinus disorders or other conditions thought to be related to the nose or sinuses. Woven through this story are the subplots of the progress of surgical technology, the understanding of anatomy and physiology, and the hit-or-miss relationship between them. Through the last half of the nineteenth century, great strides were made in understanding nasal and sinus anatomy and physiology. As that century ended and as the twentieth century began, there was a surge of technology that allowed a marked increase in the type and number of surgeries performed. Unfortunately, nasal and sinus surgery holds the awesome potential to promote health or to severely hurt someone. The knowledge of nasal physiology and anatomy had been exceeded, and often those operations were not in the patient's best interest. Through the middle of the twentieth century the basic science knowledge seems to have caught up with the care being provided, but as the end of the century approaches, another tide of surgical activity seems to be upon us. Perhaps in no other area of surgery has this disparity between biologic knowledge and surgical activity been so well demonstrated. Perhaps the next 100 years will witness a better coordination of these activities.

History, 18th Century↗
PubMed1992

[The external ear--a marker in identification].

The ear, well known anatomically in earlier investigations was only measured. We looked for 144 newborns and children (sex, age, morphology). We studied carefully and first of all systematically size, form and condition of the auricula. The form is genetically determined. Babies have a relative big ear between 9 and 15 months of age (accelerated?). In early time (20 century) this development only seen by children 3 years old. Eight specific characters changes with age (months). Outcome are proofed on 732 pupils. In forensic medicine a scientist should know this results before expertise of identification by mass disasters or unknown children.

Adolescent↗
PubMed1990

[Cause of death in severe acute ethanol intoxication].

A study of acute alcohol influence (heavy drinker) on sudden unexpected death were analyzed as to age, sex, cause of death and along with the lethal blood alcohol content. Excess alcohol abuse by adults or middle aged women causatived acute intoxication with actual toxic depression of brainstem function (high blood levels, means 3,6 mg/g). Others (alcohol abuse) die by drowning, trauma, sudden coronary death (drinking spirits), cardiomyopathy, hypothermia or hypoglycemia (Diabetes). The autopsy findings are discussed.

Adult↗
PubMed1990

[Recent developments of sex determination using various skeletal sections].

Sexualdimorphism of the skull characterized by morphological marks. Practical applications and the value represented. Epiphysial breadth of the long bones well qualified for difference sex of the bones, demonstrated by new measurements of 314 bones from adult persons. Stepwise regressions- and discriminant-analysis verify the results. Reference of the influence of acceleration and type of constitution complete the study of identification. Analysis of pictures from living persons using also pattern of the lip and marks of the ear.

Anthropometry↗
PubMed1989

[Polytrauma in childhood from the forensic medicine viewpoint].

Forensic investigations on lethal accidents of infants and teenagers inclusive biomechanic aspects. Under 523 avoidable deaths are a high number of traffic accidents. This analysis was extended to serious accidental trauma of head and/or vertebral column. Most of the children dead by lesions of CNS, violent injury of intracranial vessels and traumatic ruptured organs. Conclusions for prophylaxis are added ("Pedestrian friendly constructions" of cars, liberal education of the drivers, separate way for the bicycles).

Accidents, Traffic↗
PubMed1986

[Experimental combined impression trauma of the brain and spinal cord].

Experimental investigations in guinea pigs after impression trauma by means of the weight fall technique showed in the brain and the spinal cord cellular changes resembling as such in man. No significant differences were presented between pure craniocerebral and combined traumas in the animal brain. The impression traumas of the spinal cord produced exclusively hemorrhages in the central grey matter of the spinal cord and in one half of the cases supplementary reactionary changes of the brain. Edematous changes in the spinal cord were observed in 70% of the animals in case of pure craniocerebral traumas.

Animals↗
PubMed1985

The ex vivo plasma protein binding of theophylline in renal disease.

The plasma protein binding of theophylline was measured in 21 patients with renal disease and 21 healthy age and sex matched controls. The percentage of theophylline unbound to plasma was greater in patients with nephrotic syndrome and in chronic renal failure than in controls. In nephrotic syndrome the impairment of drug binding mirrored the marked degree of hypoalbuminaemia seen in this condition but in chronic renal failure the impairment of protein binding was greater than would be expected from the plasma albumin concentration changes. The percentage of theophylline free in plasma in renal disease may be increased (by as much as 50%). Such changes should be taken into account in interpreting the relationship between total plasma theophylline concentration and drug effect in renal disease.

Adult↗