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Biomedical subjects

J Nickels

Publications and source records attributed to J Nickels.

At least 55 records · Page 3Linked to original sources

Leydig cell tumor with gynecomastia. Report of a case with electron microscopy.

A case of Leydig cell tumor is reported and discussed. The tumor, 1.5 cm in diameter, was located in the capsule of the right testis. Gynecomastia present for 3 months was almost absent 4 months postoperatively. Preoperative hormone analysis revealed a low concentration of serum testosterone, which was normalized 1 week postoperatively. In electron microscopic examination, several intracytoplasmic microbody-like structures and 'tigroid' mitochondria were noted. These findings are similar to the three earlier descriptions of Leydig cell tumors.

Adult↗

Histological study of glutaraldehyde-processed vascular grafts of biological origin.

A total of 90 grafts of 100 mm in length was inserted as arterial and shunt conduits in 31 mongrel dogs. Histological changes before and after implantation were evaluated. Sections were stained with van Gieson, haematoxylin eosin and Wiegert's method for elastic fibres, and studied with light microscopy. Twenty five of the 42 cases studied showed classic signs of rejection around the graft, the strongest immunological response being seen in the fresh vein grafts. Glutaraldehyde pre-treatment diminished this reaction but it was still clearly visible in 13 of the 21 cases. Of the fourteen human umbilical vein grafts tanned with glutaraldehyde and used either as shunts or bypass grafts, seven showed only slight or moderate reaction and in seven cases no clear sign of rejection could be seen. The absence of intimal hyperplasia with this type of graft also showed its superiority over that of the human "non-umbilical" vein grafts. The problem in all the groups was the anastomotic area, where fibrous hyperplasia developed. The graft structure seemed to be well-preserved during the follow-up period of 6.0 months.

Animals↗

Morphological study of flow surface of glutaraldehyde pre-treated vascular substitutes.

90 grafts were inserted as arterial and shunt conduits in 31 dogs. Human saphenous veins and umbilical veins were either fresh or treated with 0.2% v/v glutaraldehyde. 72 samples from these grafts were studied morphologically. Macroscopic inspection, and light, scanning and transmission microscopy was used. The insertion time of the grafts were kept in place for periods up to 6.0 months. The tanning procedure with glutaraldehyde destroyed all normal endothelial structures. However, the new vascular interface appeared to be quite thrombo-resistant, because only slight changes were found on the flow surface following surgery. Multiple collagen fibres were seen with fibrin like deposits predominating. In those grafts which were thrombosed the thrombus had its origin at the anastomotic site and the graft itself was free of thrombus. No endothelium could be seen in any case studied. Fresh untreated saphenous vein grafts studied as controls showed clear degenerative changes and thrombus accumulation on the inner surface. The same kind of changes were found also in the anastomosing artery.

Animals↗

Granulocytic sarcoma (chloroma) of the cerebellum and meninges a case report.

A 7-year-old boy, having had headache and vomiting for one month, was operated for a tumour in the left side of the posterior fossa. The tumour, weighing 52 g, infiltrated the dura mater, leptomeninges, and also, superficially, the left cerebellar hemisphere. The patient died five weeks after operation. Light and electron microscopical examination revealed a granulocytic sarcoma (chloroma). Pre- and postoperative blood examinations, together with postoperative and autopsy bone marrow examinations, showed no sign of acute myelogenous leukaemia. This is the second reported case of primary intracranial chloroma with no preceding sign of acute myelogenous leukemia, and the first case with cerebellar infiltration.

Cerebellar Neoplasms↗

Paraganglion cells mimicking metastatic clear cell carcinoma.

Four patients are presented whom normal paraganglion cells simulated metastases of clear cell carcinomas of the urogenital tract. The cells, located within and near the lumbar sympathetic ganglia, were initially interpreted by the pathologist as metastatic, but a later examination showed them to be normal paraganglion cells. One ganglion was also examined electron microscopically. Normal ganglion cells were seen, as were cells with intracytoplasmic osmophilic neurosecretory granules, confirming their paraganglionic origin. Awareness of the appearance of paraganglion cells in some instances is essential to avoid their misinterpretation as metastases of clear cell carcinomas.

Adenocarcinoma↗

Trophoblastic pseudotumour of the uterus. A case report.

A 52-year-old woman with vaginal bleedings had hysterectomy because curettings prompted suspicion of malignancy. A uterine tumour with deep infiltration of trophoblastic cells in the myometrium was revealed. Postoperative quantitative analysis for urinary human choriongonadotropin gave 1500 IU/1. The patient got no other treatment and is well 3 years after operation. The histopathological picture and the clinical course were consistent with the recently introduced diagnosis of benign "trophoblastic pseudotumour", which should perhaps replace the old terms "syncytioma" and "chorionepitheliosis".

Diagnosis, Differential↗

Thymoma metastasizing to extrathoracic sites. A case report.

In the case presented, metastases to extrathoracic sites developed in a 53-year-old man four years after the diagnosis of inoperable thymoma had been established. The appearance of metastases was preced by an extensive intrathoracic invasion of the tumour. The thymoma was of epithelial subtype which was the most common (67 percent) type also in the previously published 29 cases of thymomas metastasizing to extrathoracic sites.

Humans↗