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Biomedical subjects

J Linder

Publications and source records attributed to J Linder.

At least 145 records · Page 8Linked to original sources

The undifferentiated malignant neoplasm. Identification of lymphoma arising in skeletal muscle by immunohistochemical analysis.

The undifferentiated malignant neoplasm presents a significant problem in the intelligent selection of therapy. Because of advances in chemotherapy, there are cancers that are effectively palliated, and sometimes cured if appropriately treated. Characterization of tumors by immunohistochemical stains drastically reduces the incidence of "undifferentiated" diagnoses and will optimize patient management, as illustrated by two cases of large-cell lymphoma arising in skeletal muscle.

Biopsy↗

Quantitative evaluation of inflammation in biopsy specimens from idiopathically failing or irritable hearts: experience in 80 pediatric and adult patients.

The histologic criteria for the diagnosis of myocarditis on an endomyocardial biopsy specimen are troubled by varying institutional criteria and interobserver differences. A comprehensive approach to tissue evaluation including quantitative assessment of mononuclear cell populations enhances the accuracy and the specificity of the morphologic diagnosis. Future efforts to characterize the infiltrating cell lines in inflammatory conditions of the heart will aid in the ultimate refinement of therapeutic efficacy.

Adult↗

Characteristics of uveal vasodilation produced by facial nerve stimulation in monkeys, cats and rabbits.

The effect of electrical stimulation of the facial nerve on ocular blood flow and intraocular pressure (IOP) was studied in monkeys, cats and rabbits. Ocular blood flow was determined with radioactive microspheres or by direct measurement of uveal blood flow from a cannulated vortex vein in rabbits. Frequency-response relationships were determined in monkeys (intraocular pressure) and rabbits (uveal blood flow). Stimulation of the facial nerve produced a marked increase (greater than 100%) in choroidal blood flow in all three species. The effect in the anterior uvea appeared the same, but less pronounced. Retinal blood flow was not affected by the stimulation in any of the species. In cats, local blood flow in the optic nerve was significantly increased by the stimulation. As there was no significant change in mean arterial blood pressure, the increase in blood flow must have been due to decreased vascular resistance. The uveal vasodilation was resistant to muscarinic blockade in all three species, excluding acetylcholine as the principal peripheral transmitter. Stimulation of the facial nerve also caused a moderate increase in IOP (range 1-11 cmH2O), only investigated in monkeys. This increase in IOP seems to be secondary to the intraocular vasodilation. The maximal increase in intraocular pressure, in monkeys, and vasodilation, in rabbits, was obtained at 15-20 Hz. At these frequencies, the vasodilation was always abolished by ganglionic blockade. In rabbits, stimulation at high frequencies (greater than 40 Hz) sometimes produced uveal vasodilation even after ganglionic blockade. This vasodilation was always less pronounced than before the ganglionic blockade and could be abolished by muscarinic blockade. The increase in uveal blood flow, in rabbits, was not affected by administration of indomethacin, indicating that prostaglandins are not critically involved in the vasodilation produced by facial nerve stimulation. The vasodilatory nerve fibers in the facial nerve are likely to be involved in regulation of choroidal blood flow to control the environmental temperature for the retina. The present study establishes the existence of efferent vasodilatory nerve fibers of facial nerve origin to the uvea. The peripheral transmitter causing the vasodilation is suggested to be vasoactive intestinal polypeptide (VIP).

Animals↗

Plasma cell granuloma of the thyroid.

Plasma cell infiltrates in the thyroid are rare. They may represent several processes, such as localized plasmacytoma, multiple myeloma, or plasma cell granuloma (PCG). It may be difficult to distinguish these disorders on the basis of morphologic features in sections stained with hematoxylin-eosin. All may be composed of mature plasma cells, without admixed macrophages or lymphocytes, that infiltrate the thyroid and adjacent connective tissue. The identification of the uncommon, but benign, PCG is facilitated by immunohistochemical staining to demonstrate an admixture of plasma cells with cytoplasmic kappa and lambda light chains. The polyclonal nature of the plasma cell infiltrate distinguishes PCG from neoplastic plasma cell proliferation.

Female↗

Immunohistochemical characterization of lymphocytes in uninflamed ventricular myocardium. Implications for myocarditis.

Evaluation of endomyocardial biopsy specimens for lymphocytic myocarditis requires accurate identification of lymphocytes, a task at times difficult considering that other myocardial interstitial cells mimic lymphocyte morphology. To wit, the number of mononuclear cells present in normal (uninflamed) myocardium has remained in doubt. We studied the myocardium from hearts that were obtained at autopsy and transvenous endomyocardial biopsy specimens with monoclonal antibodies and immunohistochemical stains to determine the normal numbers and distribution of lymphocytes in uninflamed hearts. In the ventricular myocardium of hearts obtained at autopsy, total immunohistochemically marked lymphocytes averaged 3.6/sq mm, with most being T-cell marker-positive. The ratio of T-helper to T-suppressor-cytotoxic (OKT-4:OKT-8) cells was 1.44. The number of myocardial lymphocytes demonstrated by immunohistochemical staining correlated well with, but was consistently less than, the number obtained by quantitative light microscopic studies on unmarked samples. Thus, the immunohistochemical technique allows for objective enumeration of cells and provides avenues for quantitation of lymphocyte subpopulations in inflamed hearts.

Adolescent↗

Primary malignant fibrous histiocytoma of the lung. A clinicopathologic and ultrastructural study of five cases.

Primary sarcomas of the lung are rare malignant neoplasms which have usually been classified as fibrosarcomas or as leiomyosarcomas. Only five cases of primary malignant fibrous histiocytoma (MFH) of the lung have previously been reported in the literature. The authors reviewed 10 cases of primary pulmonary sarcoma of the lung seen at their institution during the last 12 years, and five of these cases met the morphologic criteria for the diagnosis of MFH. The morphology in these cases is identical to MFH of other body locations, and shows a combination of fibroblast-like and histiocyte-like cells at both the light and electron microscopic level. By electron microscopic examination there was no evidence for anaplastic carcinoma, rhabdomyosarcoma, or leiomyosarcoma. Of the three patients with adequate follow-up, one patient is alive without evidence of disease at 10 years, one died at 5 years without evidence of recurrent sarcoma, and one died at 7 months with liver metastasis. Two other patients are alive without recurrence at 8 months and 1 year, respectively, following surgery. Because MFH is primarily a tumor of the soft tissues of the extremities, patients with MFH of the lung must be carefully evaluated to rule out a metastatic origin. The reported prognosis in patients with primary MFH of the lung is poor, but early surgical resection does offer the possibility of a cure.

Aged↗

Esophageal involvement by non-Hodgkin's lymphoma.

Esophageal involvement by non-Hodgkin's lymphoma is extremely unusual. For this reason, the differential diagnosis of symptoms referable to the esophagus in patients being treated for non-Hodgkin's lymphoma generally includes fungal or viral infection, therapy-related mucositis, and reflux esophagitis but not lymphomatous involvement. A patient is described who had development of dysphagia during treatment for lymphoma and involvement of the esophagus documented by biopsy.

Aged↗

Congenital endodermal heterotopia of the atrioventricular node: evidence for the endodermal origin of so-called mesotheliomas of the atrioventricular node.

A case of so-called mesothelioma of the atrioventricular node is presented. Controversy exists as to whether this lesion is of mesodermal or endodermal origin. The light and electron microscopic morphologic characteristics in this case were identical to those reported previously. The glandular component produced mucin that resisted digestion with both hyaluronidase and diastase; this staining pattern is characteristic of endodermal rather than of mesodermal tissue. Immunohistochemical methods demonstrated abundant carcinoembryonic antigen (CEA) in the cytoplasm of the cells composing the lesion. The presence of CEA strongly argues for an endodermal origin, since this antigen characterizes tissue derived from endoderm and is generally absent from mesoderm. The lesion probably represents endodermal foregut tissue that is displaced during embryogenesis. As such, it is not a true neoplasm. It is proposed that this lesion be designated "congenital endodermal heterotopia of the atrioventricular node."

Atrioventricular Node↗

Oncological consequences of impaired immune surveillance against ubiquitous viruses.

The immune system is constantly challenged by ubiquitous viruses. Multiple immune defenses have evolved to meet these challenges, and thus immunocompetent individuals successfully respond to infection without sequela. X-linked lymphoproliferative syndrome patients, renal allograft recipients, and acquired immunodeficiency syndrome patients share impaired immune surveillance as a common feature. Such individuals are variously susceptible to numerous untoward complications following infection with Epstein-Barr virus, cytomegalovirus, herpes simplex virus, human papillomavirus, and hepatitis B virus. We hypothesize that failure of the immune system to control these viruses is instrumental in the occurrence of some B-cell lymphomas. Kaposi's sarcoma, and squamous-cell and hepatocellular carcinomas. Herein we review some mechanisms responsible for the breakdown of immune surveillance and the permissive role immunodeficiency plays in viral oncogenesis.

Acquired Immunodeficiency Syndrome↗

Systemic kappa light-chain deposition. An ultrastructural and immunohistochemical study.

This report describes the pathology of kappa light-chain deposition in a 55-year-old patient who presented with respiratory insufficiency and hepatomegaly. Biopsies of lung and liver showed PAS-positive deposits which did not stain with congo red, crystal violet, or thioflavin-T. By indirect immunoperoxidase techniques, the deposits were composed of kappa light-chain immunoglobin. Electron microscopy revealed granular and fibrillar electron-dense material which lacked the characteristics of amyloid. Subsequent clinical studies showed this patient had a plasma cell dyscrasia. These data show that kappa light-chain deposition is not limited to the kidney, and that the first manifestation of a plasma cell dyscrasia may be systemic deposits of light chain. These deposits can be distinguished from amyloid by their immunochemical, tinctorial, and ultrastructural appearance.

Amyloidosis↗

Fibrosarcoma of the heart metastatic to the brain.

A right parietal lobe metastasis of a fibrosarcoma originating in the left atrium of the heart was resected twice in a 33-year-old man. Light microscopy showed lightly packed, pleomorphic spindle cells with abundant collagen production and an alcian blue-positive matrix. Electron microscopy confirmed the fibroblastic character of these cells. Review of the literature reveals one other cardiac fibrosarcoma metastatic to the brain. The case presented is the first reported example of successful surgical resection of this unusual metastatic sarcoma. Although he succumbed to metastatic disease, the patient remained neurologically intact until the time of death.

Adult↗