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Biomedical subjects

E J Doolin

Publications and source records attributed to E J Doolin.

18 recordsLinked to original sources

In vitro bioartificial skin culture model of tissue rejection and inflammatory/immune mechanisms.

We hypothesized that an in vitro bioartificial skin rejection model using living LSEs grown in tissue culture could be developed for the study of autologous, allogenic, and/or xenogeneic inflammatory/immune mechanisms and topical immunosuppressive drugs. Human fibroblasts were mixed with type 1 rat-tail collagen to form a matrix (4 to 5 days), on which human keratinocytes were seeded. After a keratinocyte monolayer formed, CT cultures were raised to the air-liquid interface for continued growth. In the REJ LSE model, immunocytes isolated from human blood were seeded on top of the NHEK monolayer at the time of air-lifting. Thickness measurements of the acellular keratin and keratinocyte layers, and nuclear/cytoplasmic ratios, in both CT and REJ were made using digital image analysis. Immunostaining with anticytokeratin demonstrated a viable, keratin-producing epidermal layer; staining with anti-TGF-beta suggested a role for this cytokine in the rejection or wound-healing process. The LSE appeared histologically similar to normal human epidermis. Immunocytes added to the REJ cultures caused an obvious rejection response and were clearly identifiable in the gels as CD45+ staining cells. The LSE model appears promising for the study of immune/inflammatory mechanisms, thermal injury, screening antirejection agents that might be applied topically and as an in vitro replacement for skin graft studies in animals.

Cells, Cultured

Rat renal allograft tolerance is associated with local TGF-beta and absence of IL-2r expression within chimeric immunocytic foci.

Tolerance was induced in Lewis (LEW) rat renal allograft recipients of Brown Norway kidneys by multiple pretransplant donor-blood transfusions and prior limited cyclosporine A. Rat renal allograft tolerance was associated with the induction of systemic donor T cells (10%), an early phase of nonspecific suppressor-cell generation, followed by maturation of systemic antigen-specific suppressor cells, and renal cellular infiltrates that develop long-term in situ in the kidney graft model. It was hypothesized that these infiltrates represent chimeric immunocytic foci that are locally regulated via a TGF-beta-dependent mechanism. Both immunohistochemical staining and digital image analysis for cellular and extracellular TGF-beta, IL-2 receptor (CD25), and the BN Class I-MHC marker (OX-27) were performed. Control rejecting (REJ) kidneys did not demonstrate any differences with respect to levels of infiltrating immunocyte area vs long-term surviving (TOL) kidneys (3.9% vs 4.5%, P = .303). Immunostaining with the BN Class I MHC marker (OX-27) demonstrated high levels of chimerism within immunocyte foci of the tolerant grafts (OX-27 BN+immunocytes 49.0% +/- 5.1%). In situ cellular IL-2 receptor (CD25) expression was demonstrated in REJ kidney infiltrates but not within TOL immunocytic infiltrating foci, when measured as percent of total lymphocytes (REJ = 5.0% vs TOL = 0.4%, P = .031). Conversely, TGF-beta expression was significantly higher in immunocytes of TOL kidneys when measured as the number of DAB chromogen-staining pixels per total immunocyte area (TOL = .076 vs REJ = .047, P = .003). In conclusion, these results suggested that stable mixed immune chimerism (SMIC) plays an important role in DST-CyA-induced tolerance in situ. SMIC-induced tolerance may involve a local TGF-beta-dependent mechanism that is associated with in situ TGF-beta (+) and IL-2r (-) immunocytes.

Animals

The effect of cyclosporine in gut ischemic injury: a computerized morphometric and enzymatic analysis.

PURPOSE: Gut ischemia has been implicated in the pathogenesis of necrotizing enterocolitis. Cyclosporine A (CSA), a potent immunosuppressant, attenuates immune/inflammatory cellular reactions. CSA also might be useful for inhibiting cellular immune responses involved in tissue ischemia/reperfusion injury. The authors hypothesized that CSA would attenuate inflammatory cellular changes associated with gut ischemic injury and that these effects could be quantified by computerized morphometry. METHODS: Twenty Sprague-Dawley rats underwent 60 minutes of gut ischemia by vascular occlusion of the superior mesenteric vessels. After 1 hour of reperfusion, the ischemic small bowel was harvested for histopathological examination and computerized morphometry, as well as xanthine oxidase (XO, U/mg protein) and maltase (MALT, mmol/L substrate degraded/min/mg protein) assays. CSA (5 mg/kg/d subcutaneously) was given to experimental animals (CSA, n = 10) for 5 days before ischemia, and vehicle was given to controls (CON, n = 10). The computer morphometric parameters studied were: surface index (SI, mucosal surface length per linear unit of intestine), average villous thickness (AVT), and average villous height (AVH). RESULTS: Results are provided in Table 1. CONCLUSION: The results of this study show that CSA may play a role in attenuating ischemia/reperfusion injury in the gut. Enzymatic analysis showed a beneficial role in the preservation of mucosal cell function after gut ischemia/reperfusion injury, as demonstrated by an elevated maltose level. Computerized morphometry demonstrated significant differences in all parameters in the experimental group, showing that CSA does confer gut mucosal protection during ischemia.

Animals

Morphometry and histochemistry of pulmonary arteries in a hypoplastic lung model.

Persistent pulmonary hypertension (PPH) is a common consequence of many neonatal respiratory diseases. The pathophysiology of PPH remains unknown. To study PPH, a rat model of pulmonary hypoplasia was used. Lung mass and body mass were recorded and lungs were prepared for frozen section examination and stained with hematoxylin and eosin, elastin, anti-Factor VIII, and nitro blue tetrazolium to identify nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase. The lungs were analyzed for air space volume, pulmonary artery wall thickness, total pulmonary arterial cross-sectional area, and density of tissue NADPH diaphorase staining. The mass of hypoplastic lungs was less than that of normal lungs (mean mass 85.93 mg vs 142.97 mg, P < 0.0001). The measured fraction of airspace volume was significantly less in hypoplastic lungs compared to controls (17.7% vs 30.8%, P < 0.0001). There was a significant difference in the pulmonary artery wall thickness ratio between the two groups (control 0.46 vs hypoplastic 0.487, P = 0.001). The arterial cross-sectional area was identical (control 1.25% vs hypoplastic 1.37%, P = 0.47). Staining density for NADPH diaphorase activity was determined using an intensity staining index (ISI). The experimental group showed increased staining for NADPH diaphorase (ISI = 54 in hypoplastic lungs vs 38 in controls, P < 0.01). Lung mass, appearance, and measured volume of airspace and tissue were all consistent with hypoplasia. In this model, arterial wall thickness was measurably greater in the hypoplastic group, while arterial cross-sectional area was not different. Staining for NADPH diaphorase showed significantly greater levels of enzyme in the hypoplastic lung.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Computer analyzed histology of ischemic injury to the gut.

Histopathologic alterations in the intestinal mucosa after ischemic injury have been extensively described in the literature, but these descriptions have primarily been qualitative in nature. The purpose of this study was twofold: (1) to establish parameters obtained by computerized digital image analysis that would be useful in identifying ischemic injury, and (2) to use these parameters to identify the critical period of intestinal ischemia producing measurable histopathologic change. Seventy male Sprague-Dawley rats weighing 80 to 150 g underwent various times of gut ischemic injury by vascular occlusion of the superior mesenteric artery and vein with a microaneurysm clamp. The clamp times were 0, 1, 20, 30, 40, 50, 60, 70, 80, and 90 minutes. Histological sections of the terminal ileum were quantitatively analyzed using Jandel Scientific's computerized morphometric image analysis system. Parameters studied were surface index (SI, surface length per linear unit of mucosa), average villous thickness (AVT), average villous height (AVH), and the number of villous cells/100 microns length (VC). Ischemic times of 1, 20, 30, and 40 minutes produced no measurable injury as compared with baseline (P[40 minutes versus baseline] = SI, .60; AVT, .84; AVH, .93; VC, .09). At 50 minutes, SI and AVH showed a measurable change from baseline (P[50 minutes versus baseline] = SI, .01; AVH, .02). Sixty minutes of ischemic time produced measurable change in all parameters (P[60 minutes versus baseline] = SI, .007; AVT, .001; AVH, .002; VC, .007).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Graft-versus-host disease in extremity transplantation: digital image analysis of bone marrow in situ.

The development of either unstable immune chimerism and lethal graft-versus-host disease or stable immune chimerism and alloimmune tolerance can result from extremity transplantation. LBN rats served as recipients of Lewis vascularized extremity (limb) transplants. Recipients received no immune suppression and were immunologically unmodified. The bone marrow of transplanted and contralateral limbs was analyzed in situ for distribution of nuclei, nuclear area, and staining intensity by digital image analysis and computerized morphometry. Cellularity was significantly increased, and fat content was significantly decreased in the graft-versus-host disease animals' marrow versus the tolerant animals' marrow for both the transplanted and contralateral limbs. Tolerant animals demonstrated significantly increased nuclear staining compared with graft-versus-host disease animals for both transplanted and contralateral limbs. Additionally, there were significant changes between the host and the transplanted limbs for marrow intensity and cellularity within tolerant and graft-versus-host disease groups. The significant differences in the graft-versus-host disease-positive recipients suggested that both autoimmune dysregulation and alloimmune reactions were in effect for both donor and host bone marrow compartments. Cellular alterations in the tolerant recipients' marrow were suggestive of subtle subclinical graft-versus-host responses.

Animals

Calibration of endoscopic images.

In pediatric airway surgery, endoscopic evaluation of the lesions and treatment is important. However, there are no objective and reproducible methods for measurement. The purpose of this study was to define the optical effects of a Storz-Hopkins system and develop a method of calibration and measurement. Known geometric images (grids and circles) were viewed through the Storz-Hopkins system and recorded. These images were then analyzed morphometrically with a computer image analyzer (Jandel Scientific). The distortion of the endoscope could be identified, and the severity was found to be a function of the distance from the center of the field (r = .962). When this distortion factor (range, 0% to 25% shrinkage) was used mathematically, known circles could be measured by means of an endoscopic image. The error was reduced from 17.6% to 4.3% (p < .003). With morphometric programs the optical distortion of the bronchoscope can be calibrated. This can then be used to correct the measurement of images.

Analysis of Variance

Airway measurement using morphometric analysis.

Measurement of airway size using endoscopic morphometry was investigated. Endoscopic images of the porcine tracheobronchial tree were obtained via a Storz system at a known distance from the telescope. The bronchi were marked with transluminal wires, transected, and imaged. All images were analyzed morphometrically with a computer image at multiple sites (N = 20). The endoscopic measurements were plotted against the macro lens images so that a straight line with a slope of 1 would indicate a consistent correlation. Area measurements for all images had a slope of 0.67 (r = .885); however, for images with area < 80 mm2 the slope was 1 (r = .879), for images with area < 80 mm2 of 0.93 (r = .875), and for images with area > 80 mm2 of -0.34 (r = .482), and major axis had a slope for all images of 0.73 (r = .904), for images with area < 80 mm2 of 0.88 (r = .923), and for images with area > 80 mm2 of -0.59 (r = .771). Accurate area measurements as well as major and minor axis measurements can be obtained for airways with area < 80 mm2 by means of this system. Each bronchoscope-telescope unit has an optimal target size for which measurements are accurate.

Bronchi

Composite reconstruction of the esophagus and hypopharynx after severe caustic injury.

The ingestion of caustic materials may cause burns and subsequent strictures of the esophagus. Depending on the extent of the injury, the stricture may require dilation, excision, or bypass with an esophageal replacement. There is also a risk of esophageal dysfunction, perforation, and malignancy. Here is presented a case of a burn so severe that the hypopharynx was deformed and the esophagus destroyed. Composite techniques restored complete gastrointestinal continuity while maintaining excellent swallowing function.

Adrenal Cortex Hormones

Rectal manometry, computed tomography, and functional results of anal atresia surgery.

Children with anal atresia often have compromised function. This is especially common with the anatomic "high lesion." Twenty-five patients have been studied using clinical evaluation, computed tomography (CT), and manometry to make an objective evaluation. The patients were an average of 9.6 years old; the male-to-female ratio was 3:2. Thirty-three percent had acceptable bowel function as defined by a continence score of 1 or 2. Only two (11%) had an abnormal sacrum. The mean rectal pressure was 20 cm H2O and 5 patients (23%) had a normal rectal relaxation reflex. Thirty percent had CT scans that demonstrated an intact external sphincter and puborectalis. In comparing the objective criteria and clinical results no technique could predict continence. CT demonstrated no significant group (P = .046 to .659) and manometry demonstrated no significant group (P = .082 to .752). We found no objective criteria that could evaluate the patient's clinical result or dictate therapy.

Adolescent

Esophageal stricture: an uncommon complication of foreign bodies.

Ingestion of foreign bodies is common in infants. As a rule, the infant is being observed and the event is witnessed. When it is unwitnessed, acute symptoms bring the problem to the attention of a physician. When the ingestion is not witnessed or symptomatic, its presence can only be surmised. The object can create injuries and chronic symptoms that are not typical for this accident. Here is reported an ingestion of a coin that went undiagnosed and untreated for more than a year. The result was a transmural esophageal injury with stricture formation. The diagnostic methods and transcervical repair are described.

Child

Motility abnormality in intestinal atresia.

This study was designed to investigate the motility of the small bowel of the lamb under the conditions of experimental intestinal atresia. Of 26 fetal lambs operated upon (50 to 90 days gestation), 13 came to term. All term lambs exhibited a type 3a atresia. Six were successfully repaired and had intestinal myoelectric activity monitored for periods from 2 to 27 hours. A slow wave pattern (12 to 13/min) was present in the bowel of control lambs and in the proximal dilated bowel and the microbowel of atretic lambs, confirming the presence of functional smooth muscle. Spike potentials, which indicated circular muscular contractions, occurred 10% of the time in the control intestine, 5% in the proximal dilated gut (P less than .2), and 0% in the microbowel (P less than .001). A previously undescribed myoelectric transient of variable amplitude and frequency (6 to 24/min) was identified in all lambs studied. Histologic evaluation demonstrated villous hyperplasia in the microbowel and mucosal flattening in the distended bowel. The data suggest that the quiescent microbowel distal to the atresia contributes significantly to the functional obstruction.

Animals

Familial retroperitoneal fibrosis.

Retroperitoneal fibrosis is an unusual cause of obstructive uropathy in the pediatric population. The etiology is unknown although there are laboratory and clinical associations with various autoimmune diseases. Familial associations have not been reported in children. A family is reported where two siblings have idiopathic retroperitoneal fibrosis. In addition, these sisters and the father manifest clinical laboratory evidence for systemic immunologic diseases. These young girls represent the first patients to illustrate both autoimmune and familial characteristics of this disease. These cases support the concept that retroperitoneal fibrosis is a local manifestation of a systemic immune disease.

Child

Emergency lung biopsy: friend or foe of the immunosuppressed child?

An acute pneumonic process in an immunosuppressed child poses a diagnostic and therapeutic challenge. These patients tolerate infection poorly. An open lung biopsy may provide prompt diagnosis. Nevertheless, a beneficial change in therapy that results in survival does not necessarily follow. Fifty-six immunosuppressed children with acute respiratory symptoms and interstitial pulmonary infiltrates underwent lung biopsy from 1974 to 1985. The most common underlying diagnosis was acute lymphocytic leukemia (60%). A specific etiology was determined in 46 (82%). Operative morbidity in 52% included prolonged intubation, recurrent pneumothorax, and hemorrhage. Overall, mortality was 34%. Those patients with solid tumor and those who required postoperative ventilation had a statistically significant higher mortality than all others. We defined biopsy "patient benefit" as follows: (1) the biopsy yielded an etiology for which a change of treatment was required; and (2) the child survived this acute illness. Despite the successful diagnostic results of this procedure, only 13 (23%) of the patients derived clinical benefit. Even though a specific infectious etiology was diagnosed in 39 (69%) patients only ten (18%) of these improved and survived after an appropriate change in therapy. Eight of these had Pneumocystis carinii. One survivor benefited from the treatment of documented radiation pneumonitis. Another was successfully treated for graft v host reaction but this diagnosis also was made by skin biopsy. One half of the biopsies were performed very early in the course of the illness, specifically to exclude Pneumocystis carinii of which we saw a peak incidence in 1978 to 1979.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease

Pharmacologic inhibition of scar contracture of intracardiac prosthetic patches.

Significant fibrosis and contracture often cause complications of pericardial and Dacron grafts within the heart. Both continue to be utilized because more suitable materials are unavailable. Newer prosthetic materials and the administration of drugs that might minimize intracardiac fibrosis and contracture after implantation were studied. Measured patches of three prosthetic materials were implanted into the right atrium of 18 dogs: 6 with expanded polytetrafluoroethylene (PTFE or Gore-Tex--W. L. Gore & Associates, Elkton, Md.), 6 with glutaraldehyde-preserved bovine pericardium, and 6 with Dacron patches. The animals were sacrificed after 8 weeks and gross and microscopic pathologic examinations were performed. The patch materials did not intrinsically shrink but all demonstrated marked distortion from the growth of surrounding scar tissue. In a fourth group of eight dogs with intraatrial Dacron patches, four were treated for 8 weeks with oral 3-aminopropionitrile fumarate, and four were not treated. A blinded observed evaluated the adhesions on a scale of 0 = no adhesions or patch distortion, to 4 = dense adhesions with marked distortion of the patches. The untreated dogs had dense adhesions of the lung and pericardium and the patches were encased in scar tissue with marked distortion. The average score was 3.5. The treated dogs had only minimal pleural adhesions and only a thin neointimal covering of the patch with virtually no distortion. The average score was 1.0 (P = 0.0032). The tensile strength of the healed atriotomies was evaluated with stress testing. The intact atrial wall ruptured at a force of 2.60 +/- 0.37 kg/m/sec2, the untreated atriotomy wound at 2.38 +/- 0.18 kg/m/sec2, and the treated atriotomy wound at 2.60 +/- 0.17 kg/m/sec2. There was no statistically significant difference among these groups. No other side effects of the 3-aminopropionitrile fumarate were noted, with only a single superficial wound infection caused by early postoperative trauma. Pharmacologic inhibition of scar formation minimized distortion and contracture of intracardiac prosthetic patches and decreased adhesions. Though further experimental evaluations are necessary, prolonged low-dose oral administration of beta-aminoproprionitrile (BAPN) may be beneficial in preventing complications of prosthetic implants and reoperative cardiac surgery in children.

Aminopropionitrile

Fatal iron intoxication in an adult.

An 18-year-old male accidentally fell into a vat of saturated ferrous chloride in a dilute solution of hydrochloric acid. He aspirated the iron solution to his lungs, ingested it into his stomach, and absorbed it through the burned skin. His clinical course paralleled acute iron intoxication with GI bleeding, acidosis, and transient improvement before his demise. In addition, he developed a severe disseminated intravascular coagulopathy which was temporarily ameliorated with heparin and clotting factors.

Accidents, Occupational