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Biomedical subjects

E Wilander

Publications and source records attributed to E Wilander.

At least 217 records · Page 12Linked to original sources
PubMed1975

An ultrastructural study of pancreatic islet cell destruction by n-nitrosomethylurea.

An ultrastructural study of the early effects of intraperitoneal injection of 50 mg/kg body weight of N-nitrosomethylurea on the pancreatic islet tissue in Chinese hamsters was performed. Thirty minutes after injection there was slight dilatation of the endoplasmic reticulum and mitochondrial swelling in a few peripheral alpha2-cells near to capillaries and also in some beta-cells. After 1 hour these changes were more pronounced. After 3 hours, distinct nuclear pyknosis was seen in endocrine islet cells of all types together with beta-cells granular irregularities, disruption of granular cores and autophagy of alpha2-cell granules. During the following hours, marked derangement of intracellular structures, ending in obvious cellular destruction, was observed. The results indicate that N-nitrosomethylurea has a direct cytotoxic effect on the beta-, alpha2- and alpha1-cells of the islet tissue. The similarity between the ultrastructure of the pancreatic islets after injection of N-nitrosomethylurea and streptozotocin is discussed.

Animals↗
PubMed1975

Splenic-gonadal fusion. A case report.

A case of splenic-gonadal fusion is described. In this case, as in most cases reported previously, the malformation was discovered accidentally. An ectopic spleen attached to the left testis is a rare differential diagnosis to left-sided testicular tumour.

Adult↗
PubMedDate not supplied

Monoclonal antibodies raised against mid-gut carcinoid tumor cells.

Three monoclonal IgG 2a antibodies were produced after immunization of mice with dispersed cells from a human mid-gut carcinoid tumor. Acetone-fixed cryosections of 57 primary and metastatic mid-gut carcinoid tumors as well as 2 hind-gut (rectal) carcinoids showed a conspicuous immunoreaction while a thymic carcinoid was essentially unstained with the antibodies. The 3 antibodies yielded a similar pattern of immunostaining. The immunoreaction comprised more than 95% of the carcinoid tumor cells, and it was more uniform and intense in primary tumors than in mesenteric, hepatic, and ovarian metastases of the mid-gut carcinoid tumors. Immunofluorescence studies on suspended carcinoid tumor cells showed that the antibodies bound to the surface membrane of the cells. The antibodies immunostained enterocytes of the small and large bowel, intestinal metaplasia of the stomach mucosa as well as colorectal adenocarcinomas. Endocrine pancreatic tumors producing vasoactive intestinal polypeptide, gastrin, somatostatin, and/or pancreatic polypeptide as well as the epithelium of pancreatic ducts were also stained with the antibodies, whereas a large number of other normal and abnormal human tissues, including benign and malignant insulinomas, were unreactive. The findings indicate that the antibodies recognize differentiation antigens on the carcinoid tumor cell surface preserved also on endocrine and nonendocrine cells of the normal bowel mucosa. The restricted tissue reactivity of the antibodies suggests that they may constitute useful tools in the histological characterization of carcinoid tumors. Further studies may reveal if they are applicable for immunolocalization and perhaps even immunotherapy of these neoplasms.

Antibodies, Monoclonal↗
PubMedDate not supplied

Pancreatic tumors in multiple endocrine neoplasia type 1: clinical presentation and surgical treatment.

Among 33 patients with endocrine pancreatic tumors due to multiple endocrine neoplasia type 1 (MEN-1), 19 (58%) patients had hypergastrinemia, 7 (21%) patients had hyperinsulinism, and 7 (21%) patients had clinically non-functioning lesions. At least one gross tumor was found in all patients undergoing pancreatic surgery, including those with negative localization studies prior to operation. The patients also had additional macroscopic tumors as well as numerous microadenomas, and the lesions frequently were positive for immunostaining with multiple hormones, mainly pancreatic polypeptide, insulin, glucagon, and somatostatin. Duodenal endocrine lesions were found in 4 of 5 investigated patients and stained with gastrin and somatostatin antibodies. Distal, mainly subtotal pancreatic resection, was performed in 18 patients, eventually combined with caput tumor enucleation or duodenotomy, while a few patients underwent only tumor enucleation or a Whipple procedure. The long-term outcome of operation was most favorable in patients with hyperinsulinism; only 1 patient had clinical recurrence. Patients with hypergastrinemia experienced only transitory lowering of serum gastrin values after pancreatic surgery and 47% of them had or developed metastases. Such tumor spread was seen in 57% of the patients with non-functioning lesions. Nine patients died from progressive tumor disease during follow-up. Consistent with previous studies, we found that surgery is indicated in MEN-1 patients with hyperinsulinism even if a lesion is not visualized by radiology. In addition, these indications should be extended to also include patients with only biochemical markers of disease, including elevations of gastrin, as these indicate the presence of gross tumors.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

Histopathologic examination of penile epithelial lesions is of limited diagnostic value in human papillomavirus infection.

BACKGROUND AND OBJECTIVES: Guidelines for the histopathologic diagnosis of human papillomavirus (HPV) infection have been drawn from changes seen in cervical specimens not necessarily applicable to penile epithelium. GOAL: To evaluate histopathologic examination as a means of diagnosing HPV infection of the male genital tract. STUDY DESIGN: Ninety-two consecutive male patients seen at the sexually transmitted diseases clinic. Twelve had condyloma acuminatum, and 80 had papular lesions, macular lesions, or both. Fifteen men without signs of HPV infection served as controls. Biopsy specimens were evaluated morphologically by light microscopy, and HPV DNA detection was performed by in situ hybridization and polymerase chain reaction. RESULTS: All acuminate lesions were HPV DNA positive with in situ hybridization. Forty papular and/or macular lesions harbored HPV DNA, 28 (35%) of them positive with in situ hybridization and the other 12 (15%) positive with polymerase chain reaction. Morphologic signs attributed to HPV infection were found in HPV-positive and HPV-negative penile lesions, as well as in normal epithelium. In papular and macular lesions, the only criterion associated with HPV DNA positivity was neoplastic changes, which was present in 16 (40%) HPV DNA-positive specimens, compared to 4 (10%) HPV DNA-negative specimens (P < 0.01). Of the 16 lesions with neoplasia, 15 (94%) had detectable HPV DNA of a potentially oncogenic type. CONCLUSIONS: Histopathologic signs of HPV infection other than neoplasia seem to be of limited value. Detection of the infectious agent, in this case HPV, should be the gold standard for the diagnosis as it is for other infectious diseases. The strong association between neoplasia and potentially oncogenic HPV types makes this issue even more important.

Adult↗
PubMedDate not supplied

Intracellular and extracellular fibrillar structures in gastroduodenal endocrine tumors.

Sixteen gastroduodenal endocrine tumors have been examined ultrastructurally for the presence of intracellular and extracellular fibrillar material. Intracellular juxtanuclear fibrillar bodies, often with intermingled secretory granules, were observed in one antral, one pyloric, and three duodenal tumors. In the pyloric tumor there were also extracellular fibrillar structures, which, in contrast to the intracellular fibrils, showed a green birefringence after staining with alkaline Congo red indicating the amyloid nature of these fibrils. One endocrine tumor localized to the fundus-corpus contained extracellular fibrillar bodies of a type typical of adenoid cystic carcinoma.

Adult↗
PubMedDate not supplied

Evidence of C-cell destruction in the thyroid gland of mice exposed to high 131I doses.

The parafollicular cells of the thyroid gland were visualized by means of the Sevier-Munger silver technique in normal mice and in mice receiving 131I in amounts sufficient to completely destroy the thyroid tissue. The destruction of the C-cells was observed in all 131I injected mice, and no histologic signs of recovery were seen during a period of 40 days following the treatment.

Animals↗
PubMedDate not supplied

In situ hybridization for the detection of human papillomavirus (HPV) in gynaecological biopsies. A study of two commercial kits.

Human papillomavirus (HPV) detection in biopsies from the lower genital tract may be requested by clinicians as a complement to ordinary histopathological diagnosis. In the present study, two commercial kits, (Enzo Diagnostics Inc., New York, USA and Biohit, Helsinki, Finland) used for in situ hybridization with biotinylated c-DNA probes were compared and the HPV-expression was evaluated in relation to histopathological findings. The Enzo kit identifies HPV-types 6/11, 16/18, 18 and 31/33/51, whereas the Biohit kit has separate probes for HPV 6, 11, 16, 18, 31 and 33, but none for HPV 51. The usefulness of a general probe (probemix) for the visualization of HPV irrespective of type (Enzo Diagnostics Inc.) was also studied Altogether 226 biopsies from the lower female genital tract were formalin-fixed, paraffin-embedded and processed for routine histopathological grading. Consecutive sections were employed for in situ hybridization. 50 biopsies were subject to double-testing with Enzo and Biohit, whereas 176 were tested with Enzo only. Of the double-tested biopsies, 30% displayed a nuclear staining with the Enzo kit and 28% with the Biohit kit. It is concluded that the probes of these two kits have the same sensitivity in detecting HPV in tissue sections. Condylomata acuminata were HPV-positive in 81%, mostly for types 6/11. Flat condylomas were HPV-positive in 35%. The HPV-positivity of biopsies with low grade SIL (I) was 50% and that of high grade SIL (II and III) was 37%. High grade SIL contained either HPV-types 16/18 or 31/33/51. A correlation was found between the occurrence of koilocytosis and the presence of HPV-DNA. HPV-expression was most easily visualized in condylomata acuminata. In epithelium of normal appearance or with inflammatory alterations HPV-DNA was not seen.

Biopsy↗
PubMedDate not supplied

Detection of single HPV copies in SiHa cells by in situ polymerase chain reaction (in situ PCR) combined with immunoperoxidase and immunogold-silver staining (IGSS) techniques.

Detection of HPV by means of in situ hybridization techniques may often present problems if the number of HPV copies is too small, especially when using nonradioactive detection systems. A new way of amplifying extremely small amounts of virus DNA copies is the polymerase chain reaction (PCR), which is mostly used in vitro. In this study, we present a method for in situ PCR combined with immunogold-silver staining (IGSS) and immunoperoxidase (IMP) methods which allows the detection of single copies of HPV-DNA in SiHa cells. This method may have wide applications in routine diagnostic histopathology.

Base Sequence↗
PubMedDate not supplied

Application of silver stains to cytologic specimens of neuroendocrine tumors metastatic to the liver.

Cytologic specimens of neuroendocrine tumors metastatic to the liver were examined with regard to their silver staining properties after the application of argentaffin and argyrophil staining techniques (Masson, Grimelius and Sevier-Munger). In tumors with a content of serotonin (small intestine carcinoids), the presence of this substance was demonstrated cytologically as an argentaffin reaction in individual tumor cells; however, formalin fixation was a prerequisite for positive staining. Melanin in malignant melanoma cells displayed a positive argentaffin reaction, irrespective of the fixation used (air drying, formalin, Bouin's fluid or acetone-alcohol). Thus, serotonin and melanin can be distinguished in cytologic samples of neuroendocrine tumors by the use of the Masson argentaffin reaction with different fixatives. The nonargentaffin-positive neuroendocrine tumor cells were weakly stained or unreactive with the Grimelius argyrophil technique. The Sevier-Munger argyrophil technique was negative or gave a disturbing nonspecific background staining reaction that was difficult to interpret in the cytologic samples. Thus, the Grimelius method appears to be the most useful silver stain for identifying neuroendocrine tumor cells in cytologic material, irrespective of their hormone content, since both argentaffin-positive and argentaffin-negative cell samples were stained at least to some degree.

Adenocarcinoma↗
PubMedDate not supplied

Cytologic diagnosis of a medullary carcinoma of the thyroid by Sevier-Munger silver staining and calcitonin immunocytochemistry.

A medullary carcinoma of the thyroid was preoperatively diagnosed on ultrasonically guided fine needle aspiration biopsies. After cytocentrifugation, the tumor cells displayed a dense cytoplasmic silver granulation with the Sevier-Munger technique when applied to air-dried or acetone-ethanol-fixed samples and an obvious calcitonin immunoreactivity after fixation in Bouin's fluid. These methods may prove useful in the identification of nonpalpable metastases and recurrences of medullary carcinomas of the thyroid, especially since the cytologic typing of medullary thyroid carcinoma cells may be difficult with routine stainings.

Biopsy, Needle↗
PubMedDate not supplied

Serotonin in cytologic samples of liver metastases of carcinoid tumors. An immunocytochemical study with a monoclonal antibody.

Cytologic samples of malignant carcinoid tumors were examined with regard to the presence of serotonin by immunocytochemical staining with a monoclonal antibody. Serotonin immunoreactivity occurred in tumor cells derived from carcinoids of the small intestine while bronchial carcinoid tumor cells were nonreactive. Acetone-alcohol fixation of the cells was a prerequisite for an adequate staining. The serotonin-immunoreactive tumors were also argentaffin positive. The results indicate that cytologic specimens of neuroendocrine tumors, such as carcinoid, can be successfully assayed for the presence of serotonin by an immunocytochemical procedure.

Adult↗