Morphological study of clinically nonsecreting pituitary adenomas in patients under 40 years of age

1991 ◽  
Vol 75 (6) ◽  
pp. 902-905 ◽  
Author(s):  
Shozo Yamada ◽  
Kalman Kovacs ◽  
Eva Horvath ◽  
Tadashi Aiba
Keyword(s):  
Microscopic Examination ◽  
Pituitary Adenomas ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Null Cell ◽  
Younger Patients ◽  
Content Type ◽  
Morphological Studies ◽  
Null Cell Adenomas ◽  
Fine Print

✓ Clinically nonsecreting pituitary adenomas removed at surgery from 69 patients under 40 years of age were studied by histological, immunocytochemical, and transmission electron microscopic examination. By morphological analysis. 19 tumors were found to be null-cell adenomas. 17 silent gonadotroph adenomas, 14 silent subtype 3 adenomas of unknown cellular origin, 13 silent subtype 1 or subtype 2 corticotroph adenomas, three oncocytomas, and three silent thyrotroph adenomas. These results indicate that the incidence of null-cell adenomas and oncocytomas, which are known to be the most common types of nonsecreting pituitary adenomas in patients over 40 years of age, is relatively low in younger patients. This trend is even more obvious in patients younger than 30 years of age. It can be concluded that clinically nonsecreting pituitary adenomas represent a heterogeneous group morphologically, and that the incidence of the different tumor types varies depending on the patient's age. These findings underline the importance of careful morphological studies. It is proposed that, in order for the correct morphological diagnosis to be made, tumors removed surgically from patients with clinically nonsecreting pituitary adenomas (especially younger patients) should be investigated not only by histological means but also by immunocytochemical and electron microscopic examination. The information obtained from such analysis may be useful in assessing prognosis and deciding on the appropriate treatment.

Progression of partial experimental injury to peripheral nerve

1975 ◽  
Vol 42 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Alan R. Hudson ◽  
David G. Kline
Keyword(s):  
Recovery Of Function ◽  
Electron Microscopic Examination ◽  
Ground Substance ◽  
Electron Microscopic ◽  
Early Recovery ◽  
Content Type ◽  
Proximal Stimulus ◽  
Late Recovery ◽  
Fine Print ◽  
Experimental Injury

✓ Biopsies from partially lacerated nerves were taken at the sites of proximal stimulus, laceration, and distal recording, and from stimuli and recording sites of control nerves. Electron microscopic examination of the partially lacerated major fasciculus revealed three zones of injury. The laceration zone showed neurotemetic changes, the adjacent or intermediate zone, partial degeneration, and the zone most peripheral to the laceration, changes in ground substance. Progression of the original injury is apparently due to ongoing changes in the intermediate and peripheral zones while much of the relative early recovery is due to reversal of changes in these zones. Regeneration through the laceration or neurotemetic zone is limited but does account for a small amount of late recovery of function.

Ultrastructural morphology of the olfactory pathway for cerebrospinal fluid drainage in the rabbit

1986 ◽  
Vol 64 (3) ◽  
pp. 466-473 ◽  
Author(s):  
Stephanie S. Erlich ◽  
J. Gordon McComb ◽  
Shigeyo Hyman ◽  
Martin H. Weiss
Keyword(s):  
Cerebrospinal Fluid ◽  
Connective Tissue ◽  
Electron Microscopic Examination ◽  
Olfactory Pathway ◽  
Electron Microscopic ◽  
En Bloc ◽  
Major Pathway ◽  
Content Type ◽  
Csf Drainage ◽  
Fine Print

✓ Previous physiological studies indicate that the olfactory region serves as a major pathway for cerebrospinal fluid (CSF) drainage into the lymphatic system. The present study was undertaken to determine the ultrastructural characteristics of this egress route. New Zealand White rabbits received a single bolus injection of the tracer ferritin (MW 400,000) into both lateral ventricles in such a manner as not to raise the intraventricular pressure above the normal level. The animals were sacrificed via intracardiac perfusion of fixative between less than 12 minutes and 4 hours following injection. The cribriform region was removed en bloc, decalcified, sectioned coronally, and prepared for light and electron microscopic examination. The arachnoid, dura, and periosteum surrounding the fila olfactoria passing through the cribriform plate merge together and form the perineurium, which consists of multiple layers of loosely overlapping cells with widely separated junctions and few vesicles. The perineurium surrounding the olfactory filaments at the superficial submucosal level is only one cell thick. The subarachnoid space freely communicates with the perineural space surrounding each filament. No morphological barrier between the perineural space and the loose submucosal connective tissue was identified. Whether or not the perineurium was multi- or singlelayered, ferritin was noted in abundance between the loosely overlapping perineural cells and in the submucosal connective tissue. The distribution of ferritin at 12 minutes was similar to that at 4 hours; however, the quantity of ferritin was increased at 4 hours. These results indicate that no significant barrier to CSF drainage is present at the rabbit cribriform region and that CSF reaches the submucosal region rapidly via open pathways.

Multiple pituitary adenomas in Cushing's disease

2000 ◽  
Vol 93 (5) ◽  
pp. 753-761 ◽  
Author(s):  
John K. Ratliff ◽  
Edward H. Oldfield
Keyword(s):  
Cushing’S Disease ◽  
Medical Records ◽  
Pituitary Adenomas ◽  
Cushing's Disease ◽  
Clinical Database ◽  
Null Cell ◽  
Content Type ◽  
Initial Surgery ◽  
Repeated Surgery ◽  
Fine Print

Object. Clinically evident multiple pituitary adenomas rarely occur. The authors assess the incidence and clinical relevance of multiple adenomas in Cushing's disease.Methods. A prospective clinical database of 660 pituitary surgeries was analyzed to assess the incidence of multiple pituitary adenomas in Cushing's disease. Relevant radiographic scans, medical records, and histopathological reports were reviewed.Thirteen patients with at least two separate histopathologically confirmed pituitary adenomas were identified. Prolactinomas (nine patients) were the most common incidental tumors. Other incidental tumors included secretors of growth hormone ([GH], one patient) and GH and prolactin (two patients), and a null-cell tumor (one patient). In two patients, early repeated surgery was performed because the initial operation failed to correct hypercortisolism, in one instance because the tumor excised at the initial surgery was a prolactinoma, not an adrenocorticotropic hormone—secreting tumor. One patient had three distinct tumors.Conclusions. Multiple pituitary adenomas are rare, but may complicate management of patients with pituitary disease.

Pathology of invasive pituitary tumors with special reference to functional classification

1986 ◽  
Vol 65 (6) ◽  
pp. 733-744 ◽  
Author(s):  
Bernd W. Scheithauer ◽  
Kalman T. Kovacs ◽  
Edward R. Laws ◽  
Raymond V. Randall
Keyword(s):  
Pituitary Adenomas ◽  
Prognostic Significance ◽  
Pituitary Tumors ◽  
Thyroid Stimulating Hormone ◽  
Biological Behavior ◽  
Null Cell ◽  
Content Type ◽  
Acth Cell ◽  
Ultrastructural Characteristics ◽  
Fine Print

✓ Pituitary adenomas may remain intrasellar or infiltrate dura and bone. Invasive adenomas are not considered to be malignant; in biological behavior they are between non-infiltrative adenomas and pituitary carcinomas. The latter are defined as tumors with subarachnoid, brain, or systemic metastasis. Invasion may be defined radiologically, operatively, or histologically. On the basis of operatively assessed tumor size and gross invasion of dura and bone as well as immunocytochemical and ultrastructural analysis of 365 pituitary adenomas, the following data were obtained. There were 23 growth hormone (GH)-cell adenomas: 14% microadenomas and 86% macroadenomas; their overall frequency of invasion was 50%. There were 24 prolactin (PRL)-cell adenomas: 33% microadenomas and 67% macroadenomas, with an overall frequency of invasion of 52%. Mixed GH-cell and PRL-cell adenomas were found in 35 cases; 26% were microadenomas and 74% were macroadenomas, and the overall frequency of invasion was 31%. Sixty patients had adrenocorticotropic hormone (ACTH)-cell adenomas (Cushing's disease): 87% microadenomas and 13% macroadenomas; the overall frequency of invasion was 25% (in 8% of microadenomas and 62% of macroadenomas). Twenty patients had ACTH-cell adenomas (Nelson's syndrome): 30% microadenomas and 70% macroadenomas; the overall frequency of invasion in these cases was 50% (in 17% of microadenomas and 64% of macroadenomas). Silent ACTH-cell adenomas, 100% macroadenomas, were found in 11 patients, with an 82% frequency of invasion. There were 32 follicle-stimulating and luteinizing hormone adenomas, all macroadenomas, with a frequency of invasion of 21%. Four patients had thyroid-stimulating hormone adenomas, all macroadenomas, with a 75% frequency of invasion. Null-cell adenomas were found in 93 cases: 2% microadenomas and 98% macroadenomas, with a frequency of invasion of 42%. There were 63 plurihormonal adenomas (GH, PRL, glycoprotein): 25% microadenomas and 75% macroadenomas, with a 50% overall frequency of invasion. Based on this study, and on their usual frequency of occurrence, the estimated rate of gross invasion by pituitary adenomas of all types is approximately 35%. It is concluded that immunocytochemical and ultrastructural characteristics of pituitary adenomas reflect the tendency of these tumors to infiltrate and hence may be of prognostic significance.

Suprasellar peri-infundibular ectopic adenohypophysis in fetal and adult brains

1985 ◽  
Vol 63 (1) ◽  
pp. 113-115 ◽  
Author(s):  
Akira Hori
Keyword(s):  
Pituitary Adenomas ◽  
Anterior Pituitary ◽  
Normal Adult ◽  
Pars Tuberalis ◽  
Pituitary Cells ◽  
Electron Microscopic ◽  
Content Type ◽  
Cell Groups ◽  
Immunohistochemical Methods ◽  
Fine Print

✓ Ectopic anterior pituitary cells, identified by histological, electron microscopic, and immunohistochemical methods, were consistently found in the leptomeninges of the suprasellar peri-infundibular region of fetal brains. The cell groups were not in continuity with the pars tuberalis of the adenohypophysis. Suprasellar peri-infundibular ectopic pituitary cells, which snowed no neoplastic character, were found in 15 of 20 “normal” adult brains that were similarly examined. This finding sheds new light on the possible origin of intracranial ectopic pituitary adenomas.

Ectopic pituitary adenoma of the third ventricle

1990 ◽  
Vol 72 (1) ◽  
pp. 139-142 ◽  
Author(s):  
B. K. Kleinschmidt-DeMasters ◽  
Ken R. Winston ◽  
David Rubinstein ◽  
Mary H. Samuels
Keyword(s):  
Pituitary Adenoma ◽  
Neurological Examination ◽  
Pituitary Adenomas ◽  
Sphenoid Sinus ◽  
Third Ventricle ◽  
Electron Microscopic ◽  
Content Type ◽  
The Third ◽  
Ectopic Pituitary Adenoma ◽  
Fine Print

✓ Ectopic pituitary adenomas without associated intrasellar adenomas are rare and are usually located in the sphenoid sinus. Most have been reported without modern radiological, endocrinological, or electron microscopic (EM) documentation. The case of a 47-year-old man with a third ventricular, ectopic, clinically non-secretory pituitary adenoma, which was shown to be a gonadotrophic adenoma by immunohistochemical and EM study, is reported. Neurological examination, extensive neurodiagnostic imaging, surgical anatomical observation, and endocrinological evaluation showed no evidence of neoplasia outside the third ventricle.

Properties of Isolated Mitochondria of Agaricus Bisporus: Their Relationship to Dormancy and the Germination of Spores

1973 ◽  
Vol 31 ◽  
pp. 458-459
Author(s):  
K. S. McCarty ◽  
R. F. Weave ◽  
L. Kemper ◽  
F. S. Vogel
Keyword(s):  
Mitochondrial Dna ◽  
Ethidium Bromide ◽  
Microscopic Examination ◽  
Agaricus Bisporus ◽  
Osmotic Shock ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Isolated Mitochondria ◽  
Dna Strands ◽  
Cytoplasmic Ribosomes

During the prodromal stages of sporulation in the Basidiomycete, Agaricus bisporus, mitochondria accumulate in the basidial cells, zygotes, in the gill tissues prior to entry of these mitochondria, together with two haploid nuclei and cytoplasmic ribosomes, into the exospores. The mitochondria contain prominent loci of DNA [Fig. 1]. A modified Kleinschmidt spread technique1 has been used to evaluate the DNA strands from purified whole mitochondria released by osmotic shock, mitochondrial DNA purified on CsCl gradients [density = 1.698 gms/cc], and DNA purified on ethidium bromide CsCl gradients. The DNA appeared as linear strands up to 25 u in length and circular forms 2.2-5.2 u in circumference. In specimens prepared by osmotic shock, many strands of DNA are apparently attached to membrane fragments [Fig. 2]. When mitochondria were ruptured in hypotonic sucrose and then fixed in glutaraldehyde, the ribosomes were released for electron microscopic examination.

Artifact-free electron microscopic immunocytochemistry on rat brain tissue

1991 ◽  
Vol 49 ◽  
pp. 272-273
Author(s):  
Veronika Burmeister ◽  
N. Ludvig ◽  
P.C. Jobe
Keyword(s):  
Microscopic Examination ◽  
Free Electron ◽  
Electron Microscopic Examination ◽  
Ultrastructural Localization ◽  
Rabbit Serum ◽  
Electron Microscopic ◽  
Electron Microscopic Immunocytochemistry ◽  
Phosphate Buffered Saline ◽  
Rat Brain Tissue ◽  
Immune Rabbit

Electron microscopic immunocytochemistry provides an important tool to determine the ultrastructural distribution of various molecules in both normal and pathologic tissues. However, the specific immunostaining may be obscured by artifactual immunoreaction product, misleading the investigator. Previous observations show that shortening the incubation period with the primary antibody from the generally used 12-24 hours to 1 hour substantially reduces the artifactual immunostaining. We now extend this finding by the demonstration of artifact-free ultrastructural localization of the Ca2/calmodulindependent cyclic nucleotide phosphodiesterase (CaM-dependent PDE) immunoreactivity in brain.Anesthetized rats were perfused transcardially with phosphate-buffered saline followed by a fixative containing paraformaldehyde (4%) and glutaraldehyde (0.25%) in PBS. The brains were removed, and 40μm sections were cut with a vibratome. The sections were processed for immunocytochemistry as described by Ludvig et al. Both non-immune rabbit serum and specific CaM-dependent PDE antibodies were used. In both experiments incubations were at one hour and overnight. The immunostained sections were processed for electron microscopic examination.

Ultrastructural studies of Chlamydia psittaci 6BC variant strains. I. Ultrastructure of the surface layers of egg-passaged 6BC strain

1973 ◽  
Vol 19 (8) ◽  
pp. 887-894
Author(s):  
Linda Poffenroth ◽  
J. W. Costerton ◽  
Nonna Kordová ◽  
John C. Wilt
Keyword(s):  
Chick Embryo ◽  
Microscopic Examination ◽  
Electron Microscopic Examination ◽  
Chlamydia Psittaci ◽  
Gram Negative Bacteria ◽  
Surface Layers ◽  
Electron Microscopic ◽  
Gram Negative ◽  
Ultrastructural Studies ◽  
First Time

Electron microscopic examination of a semipurified Chlamydia psittaci 6BC strain attenuated in chick embryo yolk sac revealed for the first time two morphologically distinct small elementary bodies which differ both in the ultrastructure of their surface layers and in their buoyant densities in sucrose gradients. Also, the morphology of the surface layers of the larger reticulate forms in cell-free systems is described for the first time. Many points of difference between the surface envelopes and internal structure of chlamydial particles and those of Gram-negative bacteria are discussed.

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