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Biomedical subjects

W R Anderson

Publications and source records attributed to W R Anderson.

At least 91 records · Page 5Linked to original sources
PubMed1985

Hemosiderosis and hemochromatosis in renal transplant recipients. Clinical and pathological features, diagnostic correlations, predisposing factors, and treatment.

We analyzed the clinical data and liver histology for iron overload in 74 renal allograft recipients. Twenty of the 74 patients had histological evidence of hemosiderosis. Four patients had hemochromatosis. Of the 2 noninvasive diagnostic tests the serum ferritin level was more reliable than percent saturation of transferrin in predicting the histological diagnosis of hemosiderosis. Of the 20 patients with hemosiderosis 14 died either from liver failure or concomitant sepsis. Female patients and those who received long-term dialysis had higher susceptibility for developing hemosiderosis. Of the 6 patients treated with phlebotomies, the response was good in 4 and incomplete in 2. Hemosiderosis and hemochromatosis should be considered in the differential diagnosis of posttransplant liver disease. Intermittent phlebotomies if carried out early may prevent the progression of hemosiderosis to micronodular cirrhosis.

Adult↗
PubMed1985

Course of hepatic regeneration after 80% to 90% resection of normal rat liver. Comparison with two-lobe and one-lobe hepatectomy.

After subtotal (80% to 90%) hepatectomy of the normal rat liver, thymidine kinase activity began to increase after 24 hours and reached a maximum at 36 hours. This persisted for another 60 hours before it declined to reach the baseline by 7 to 8 days. The maximal increase was 30- to 50-fold. After two-lobe (67% to 78%) hepatectomy, the maximal increase was similar, but the onset and the maximum each occurred 12 hours earlier, and the maximum only persisted for another 24 hours. The important first peak of ornithine decarboxylase activity occurred earlier and rose higher after 67% to 78% hepatectomy. The distributions with time of histologic mitosis counts were similar to the distributions of thymidine kinase activity (reflects DNA synthesis) at each of the three levels of hepatectomy, 80% to 90%, 67% to 78% and 37% +/- 0.5%. Thus the initiation of regeneration was delayed after subtotal resection, but the regenerative response as reflected by DNA synthesis and cell multiplication was prolonged.

Alanine Transaminase↗
PubMed1985

Acetaminophen liver injury: sequential changes in two biochemical indices of regeneration and their relationship to histologic alterations.

Massive liver injury was produced in fasting male Sprague-Dawley rats weighing 200 +/- 25 gm each by gastric administration of 1400 mg/kg acetaminophen. The time sequence of changes in liver ornithine decarboxylase (ODC) activity, which reflects the earliest phases of cell multiplication, liver thymidine kinase (TK) activity, which reflects DNA synthesis, and liver histology (necrosis, mitosis, and repair processes) was recorded. ODC showed the usual biphasic response. By 12 hours, it reached its first peak, a six- to eightfold increase. At this time there was no histologic evidence of necrosis, and serum malate dehydrogenase (MDH), sorbitol dehydrogenase (SDH), and alanine aminotransferase (SGPT) were normal. During the next 12 hours ODC decreased by 60% to 70% and cellular necrosis became evident, and reached a peak at 24 to 36 hours, as did serum MDH, SDH, and SGPT. The serum enzymes fell precipitously at 48 hours, but the histologic evidence of necrosis subsided gradually over 60 hours. The secondary ODC peak, a fourfold increase, coincided with rising activity of TK, which increased 25- to 35-fold over 54 to 72 hours, and then subsided. At 54 hours, when DNA synthesis had already peaked, there was no histologic evidence of repair other than mitoses. However, within the next 6 hours, evidences of repair became prominent, and remained so for another 36 hours before subsiding. Thus, with acetaminophen injury, the initial phases in preparation for cell multiplication occurred before histologic evidence of injury was apparent, and DNA synthesis peaked before other evidence of tissue repair became evident.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetaminophen↗
PubMed1984

Pulmonary oxygen toxic effect. Occurrence in a newborn infant despite low PaO2 due to an intracranial arteriovenous malformation.

A newborn infant with a massive left to right shunt secondary to a cerebral arteriovenous malformation required continuous oxygen therapy in high concentrations. Despite high PO2, the infant maintained low to normal PaO2 concentrations. Light and ultrastructural studies of the lungs demonstrated typical changes of acute pulmonary oxygen toxicity, including degeneration of capillary endothelium and type I pneumonocytes, interstitial edema, and alveolar exudation. These observations confirm earlier experimental animal studies that demonstrated that the alveolar Po2 concentration and not the Pao2 is the major factor contributing to pulmonary oxygen toxic effect.

Humans↗
PubMed1984

Urinary retention in female patients induced by adenocarcinoma of urethra.

Acute urinary retention in middle-aged females is an infrequent occurrence; therefore, when such a patient presents to the urologist, an aggressive diagnostic evaluation is warranted. Carcinoma of the urethra might be the underlying pathologic process causing urinary retention. Herein, we present 2 cases of acute urinary retention triggered by adenocarcinoma of the urethra. In 1 patient the diagnosis was delayed due to severe superimposed infection which responded poorly to medication. Anterior exenteration and radiotherapy were used in the management of both patients.

Adenocarcinoma↗
PubMed1983

Diagnosis of swine trichinosis by enzyme-linked immunosorbent assay (ELISA) using an excretory--secretory antigen.

An excretory--secretory (ES) antigen was used in a serodiagnostic enzyme-linke immunosorbent assay (ELISA) for swine trichinosis. ELISA procedures included a double-antibody test, using either an anti-swine IgG or a protein A enzyme conjugate, and a triple-antibody test using a pig IgG heavy-chain specific second antibody with a conjugated third antibody. The ES antigen was effective in eliminating all false-positive reactivity in sera from farm-raised hogs. The triple-antibody procedure was more sensitive and demonstrated a greater efficiency in detecting positive animals and early seroconversions. Naturally-infected pigs with worm burdens as low as 0.01 larvae per gram (LPG) of diaphragm were seropositive using these procedures. Seroconversion in experimentally-infected animals receiving low doses of muscle larvae (500) occurred considerably later than in animals receiving high doses (10000). This might account for false-negative reactions in naturally-infected animals with very low (less than 0.1 LPG) worm burdens.

Animals↗
PubMed1983

Cardiopulmonary sequelae of reparative stages of bronchopulmonary dysplasia.

Seventy-three infants died after intensive respiratory therapy that included supplemental oxygen; their survival ranged from three to 225 days. Pulmonary alterations began with an exudative, early reparative stage and progressed to subacute and chronic fibroproliferative stages that correlated with stages 2 through 4 of bronchopulmonary dysplasia. Cardiopulmonary complications of interstitial fibrosis, emphysema, and cor pulmonale were most pronounced in the longest survivors and were associated with progression of the reparative response to the chronic fibroproliferative stage. An obliterative bronchiolitis was also a frequent manifestation of this reparative response, which may account for cystic bronchiolectasis observed in five infants. Ultrastructural studies indicated that the type 2 pneumocyte contributed to the reparative and proliferative reactions by reepithelialization of damaged septal walls and incorporation of hyaline membranes into septal walls that seemed to stimulate interstitial fibroplasia.

Bronchi↗
PubMed1982

Patterns of periovulatory oviductal motility and progesterone in the unanesthetized rabbit.

Pairs of miniature extraluminal force transducers were chronically implanted on the isthmus of 26 rabbits without disturbing reproductive function. No alterations were noted in the transducer-bearing animals in the numbers of corpora lutea, uterine implants, or viable conceptuses, or in fertility, pregnancy rates, rates of ovum transport, or peripheral plasma levels of progesterone (P) or estradiol (E2). Using these devices, isthmic motility was recorded in 14 unanesthetized rabbits throughout the 72 h following human chorionic gonadotropin injection (hCG) (75 IU) and coitus. This activity was comprised of distinct bursts (B) of intense contractile activity, interspersed with periods (IB) of relative quiescence. Although the basic pattern of B and IB periods persisted throughout this interval, significant changes were noted in the duration of its components. During this period, B durations increased, with all values greater (P less than 0.01) than estrus from 24 h following the ovulatory stimuli. IB durations diminished somewhat at 24 h, but were markedly prolonged at 60 and 72 h. The proportion of time spent in bursting activity was maximal and significantly greater than estrus (P less than 0.01) at 24 h, a time at which ova were retained at the ampullary-isthmic junction. This proportion was minimal, on the other hand, at 60 and 72 h, when ova were moving rapidly through the isthmus and uterotubal junction. Plasma P surged from estrus to a peak at 6 h, fell until 24 h, and gradually increased through 72 h. All post-stimulus P values were greater (P less than 0.01) than at estrus. The B and IB durations at 72 h were both positively correlated with the P levels at 6 h. These findings suggest the importance of specific patterns of isthmic motility in ovum transport and of P in its regulation.

Animals↗
PubMed1982

Hemosiderosis: an unrecognized complication in renal allograft recipients.

During the past decade, 258 patients received 293 renal transplants at Hennepin County Medical Center Minneapolis, Minnesota. Twenty-three of these patients had a pretransplant liver biopsy. Thirty-six patients had liver biopsies done during the post-transplant period. Liver tissue at autopsy was available from 24 patients who died after receiving a kidney transplant. Systematic analysis of the biopsy and autopsy specimens with appropriate tissue stains showed significant iron deposition (3+ to 4+) within the hepatic parenchymal cells in 1 of the 23 (4%) pretransplant biopsies and 17 of the 60 (28%) post-transplant specimens (P = 0.02). Eight of the 17 (47%) patients with post-transplant hemosiderosis also exhibited histological features of liver cirrhosis. As hemosiderosis is reversible with intermittent phlebotomies, early recognition and adequate management are highly desirable. We suggest that the serum ferritin level, which is a reliable index of body iron stores, should be monitored in all patients at periodic intervals following renal transplantation.

Adolescent↗
PubMed1982

Evaluation of three immunodiagnostic procedures for porcine strongyloidiasis.

An indirect fluorescent antibody test (IFAT), an indirect radioimmune antibody test (IRAT), and an enzyme-linked immunosorbent antibody assay (ELISA) were compared for their efficacies in detecting antibody to Strongyloides ransomi in pigs. The greatest sensitivity was exhibited by the ELISA, using a soluble, whole larval extract. The 2 indirect antibody assays, IFAT and IRAT, using intact 3rd-stage larvae (L3) were comparable in sensitivities. The use of live L3 in the IFAT and IRAT presented technical problems, because the larvae shed antibody complexes at ambient room temperature. This could be inhibited by the addition of 20 mM of sodium azide to all working solutions or by doing the tests at 4 C. Fixation of the L3 by either formalin or heat also eliminated the shedding problem. The specificities of the ELISA and IFAT were supported by the negative results obtained with serum from pigs infected with Ascaris suum, Stephanurus dentatus, and Trichinella spiralis.

Animals↗
PubMed1980

A miniature extraluminal force transducer for recording in vivo oviductal motility.

A miniature extraluminal force transducer has been developed and used to record acute and chronic motility of the reproductive tract in the rabbit. This device, which contains two matched piezoresistive silicon sensors bonded to a titanium beam strip, is durable, physically stable, and highly sensitive to bending force (gage factor, 140). Acute recordings made in 20 rabbits revealed continuous, rhythmic contractile activity in both the oviduct and uterus. Chronic recordings made in three unanesthetized rabbits revealed periodic bursts of intense activity interspersed with periods of relative quiescence. Chronic implantation of these devices was accomplished with no evidence of infection, adhesions, or other abnormalities, and without disruption of fertility.

Animals↗
PubMed1980

Histopathologic study of adverse effects of linoleic acid on rat lung.

Linoleic acid administered intravenously was highly toxic to the rat lung. The severity of the toxicity paralleled the dosage administered and was characterized by generalized, irreversible damage to alveolar wall structures. Although evidence of tissue damage was not apparent or minimal by light microscopy, ultrastructural studies disclosed extensive degeneration and necrosis of septal wall components with 15 minutes following injection of low dosages of linoleic acid. Degeneration of endothelial cells was most severe suggesting that these cells were the target of injury resulting in impaired vascular integrity, interstitial and alveolar edema, and degeneration of type 1 pneumocytes. Fragmentation and stripping of endothelium from capillary basement membranes was uniformly present and was in some instances associated with platelet aggregation indicative of early thrombosis. These studies suggest that this toxic effect on septal capillaries leading to increased permeability and alveolar edema may be a contributing factor to death occurring from free fatty acid toxicity in the human.

Animals↗