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Previous work has demonstrated that vitamin A-deficient, retinoic acid-supplemented pregnant rats cannot complete gestation without the administration of retinol. As little as 2 micrograms administered on day 10 of gestation is sufficient to prevent the characteristic fetal resorption that begins at day 15 of gestation. This single dose of retinol supports continued development through day 20 of gestation. However, if gestation is allowed to proceed to parturition, the newborn pups die within a few minutes of being severed from the umbilical cord. The pups are born with a pink and healthy skin tone, but within seconds of umbilical separation, they begin to gasp for air, become cyanotic in appearance, and die within several minutes from an apparent inability to obtain oxygen. Histological examination of these neonates demonstrates delayed pulmonary development. Branching and scalloping of ducts and saccule and subsaccule formation are decreased. This phenotype is consistent with that observed in respiratory distress syndrome seen in some premature human infants.

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Aspirates of bone marrow with chronic lymphocytic leukemia, hairy cell leukemia, and Richter's syndrome were stained by the argyrophilic nucleolar organizer region (AgNOR) method and analyzed. The AgNOR configurations of small cells of chronic lymphocytic leukemia, hairy cell leukemia, and lymphosarcoma cells were similar and most often consisted of a single large dot, a single small regular bleb, and two dots of various sizes, similar to patterns of normal lymphocytes. The large cells of chronic lymphocytic leukemia and prolymphocytic leukemia cells transformed from chronic lymphocytic leukemia contained larger AgNORs (group II), that is patterns consistent with proliferation. Richter's syndrome lymphoma cells contained even larger AgNORs. A single large regular bleb, small regular bleb and large irregular bleb were most common. Cells with only small structures were very rare.

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Previous observations indicated that a colloidal silver (AgNOR) method identifies iron-containing bone marrow cells. In this study we examined AgNOR-stained bone marrow smears from 30 selected patients and compared the results with the conventional Prussian blue (PB) method for staining storage iron and sideroblasts, including ringed sideroblasts (RS). Erythroid cells were easily identified, and iron granules stained as distinct, small, round, black dots. In all cases containing sideroblasts and RS, their proportion expressed as the percentage of all normoblasts was higher with AgNOR than with PB. Pronormoblastic and basophilic sideroblasts were detected more often with AgNOR than with PB. Sideroblasts were noted in cases with no PB-stainable iron. Ringed sideroblasts were identified in a number of cases in which they were nondetectable with PB. In cases of myelodysplastic syndrome, pronormoblastic and basophilic RS were found more often than with PB. Hemosiderin deposits within the macrophages were clearly visualized as black aggregates and were seen in cases with no PB-stainable iron. There were no instances where iron or any category of sideroblasts was seen with PB only. In our sampling, the AgNOR method was more sensitive yet specific, and it produced staining results of superior quality.

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Fifteen normal bone marrow aspirates were stained with the agyrophilic nucleolar organiser region (AgNOR) method. The results of the specific staining AgNORs as well as nuclear and cytoplasmic staining were analysed. A system was devised to characterise precisely the AgNORs present in the nuclei of bone marrow cells. Particular types of bone marrow cells had a characteristic AgNOR and non-AgNOR staining pattern. The bone marrow cells were identified easily and reliably with AgNOR staining and the method was especially useful for lymphocytes, plasma cells, erythroid cells, basophils/mast cells, monocytes and cells containing haemosiderin. The immature haemopoietic cells exhibited more and larger AgNORs than the more mature cells. It is concluded that AgNOR staining can be used to study bone marrow cells by providing additional information when used in conjunction with conventional stains.

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The binding, internalization, and fate of interleukin-2 (IL-2) were studied in phytohemagglutinin (PHA)-activated human lymphocytes using biotinylated recombinant IL-2 (rIL-2). Streptavidin adsorbed to 18-nm colloidal gold beads (Au18-streptavidin) and streptavidin covalently bound to horseradish peroxidase (HRP-streptavidin) were used to follow the movement of biotinylated rIL-2 within cells over a 4-hour period. Results obtained from either probe were similar. Biotinylated rIL-2 was taken up in coated pits, transferred to a series of small uncoated vesicles and tubules in the peripheral cytoplasm of the cell, then concentrated and sequestered in uncoated vesicles, multivesicular bodies (MVB), and dense bodies (DB) in the peripheral and juxtanuclear cytoplasm of the cell. Occasionally, MVB containing Au18-streptavidin, or HRP-streptavidin, appear to have fused with the plasma membrane of the cell. No labeling of the Golgi cisternae, nuclear envelope, or nucleus was observed. Results from a competitive receptor binding assay and a cell proliferation assay indicate that both the affinity of rIL-2 for high affinity rIL-2 receptors and the proliferative activity of rIL-2 were negligibly affected by the biotinylation procedure. These studies suggest that in activated lymphocytes, IL-2 is bound to receptors on the cell surface, gathered in coated pits, internalized by receptor-mediated endocytosis, concentrated in the endosomal compartments, and delivered to lysosomes for degradation.

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Our understanding of the histology and histopathology of the endolymphatic sac (ELS) is based on both temporal bone preparations and biopsy material. The current study will provide the basis for an ultrastructural analysis of the spectrum of pathologic changes observed in biopsy specimens from patients with endolymphatic hydrops in Meniere's disease. Emphasis is placed on the distribution and density of subepithelial collagen in the ELS of normal and hydropic patients. This study will be the light microscopic basis for an ultrastructural clinicopathologic correlation of inner ear tissue from the ELS with the clinical stage of the disease.

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Male and female Sprague-Dawley rats (70 males and 70 females in the initial group) were fed a diet containing a polychlorinated biphenyl mixture (Aroclor 1260, 100 ppm for 16 months and 50 ppm for an additional 8 months) for 2 years followed by a control diet for 5 months. A control group initially consisted of 63 males and 63 females. Sequential morphologic changes were evaluated throughout the study. In the PCB-exposed group the following hepatocellular lesions developed in sequence: centrolobular cell hypertrophy at 1 month, foci of cell alteration at 3 months, areas at 6 months, neoplastic nodules at 12 months, trabecular carcinoma at 15 months, and adenocarcinoma at 24 months. In addition, simple and cystic cholangioma at 18 and 23 months, respectively, and adenofibrosis at 22 months were present. With the exception of hepatocyte hypertrophy and adenofibrosis, all lesions contained cells that were positive for gamma glutamyl transpeptidase activity. In the PCB-exposed group that was examined after 18 months, hepatocellular neoplasms were present in 95% of the 47 females and in 15% of the 46 males. Distant organ metastases did not occur and the mortality rate was not increased in the PCB exposed group. In 81 control rats examined after the 18th month, only 1 hepatocellular neoplasm (a neoplastic nodule) occurred. PCB- exposed and control rats developed simple cholangioma, cystic cholangioma and adenofibrosis; the incidence of each was greater in the PCB group. Thus, within the Sprague-Dawley rat group exposed to a diet with relatively high concentrations of Aroclor 1260 for 2 years a hepatocarcinogenic effect manifested by formation of slowly growing hepatocellular carcinomas was produced.

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In vitro growth patterns and morphologic characteristics of five low-grade human papillary transitional cell carcinomas (TCCs) were compared and contrasted with those of normal human urothelial cells in culture. Biopsies of TCC were performed by transurethral resection. Specimens of normal human ureters were obtained surgically. Singly dispersed TCC cells grew in 0.3% agarose semisolid medium with a cloning efficiency ranging from 0.02% to 0.71%. Singly dispersed normal ureteral urothelial cells under the same conditions did not form colonies in 0.3% agarose. Neither singly dispersed TCC nor normal urothelial cells formed colonies when plated on collagen-gel substrates. In primary explant culture, normal human urothelial cells grew rapidly, to form tightly adherent flat sheets of apparently nonmotile cells. Autoradiographic labeling with 3H-thymidine of growing cultures of normal urothelial cells showed cell division primarily in the zones of growth near the explant. Outgrowth of TCC from primary explants was loosely adherent. One TCC explant culture gave rise to a continuous suspension culture. Numerous multilayered cellular formations of fronds, nodules, and "walls" were seen around the periphery of TCC explant colonies. Autoradiography showed that these multilayered areas of TCC growth contained actively dividing cells. The altered ability of papillary TCC to form superficial multilayered formations in vitro distinguishes them from normal human urothelium and reflects the morphologic characteristic of this tumor type in vivo.

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Long-term administration of carbon tetrachloride to rats has produced proteinuria and histopathologic glomerular alterations. The present study was done to determine the effect of prior reduction of renal mass on the long-term nephrotoxicity of carbon tetrachloride. Female Sprague-Dawley rats with uninephrectomy received twice-weekly intraperitoneal injections of either corn oil or corn oil with 0.05 to 0.1 ml carbon tetrachloride. Rats were studied for up to 36 weeks. Increased urinary protein and albumin excretion was noted in the rats receiving carbon tetrachloride after ten weeks. Glomerular abnormalities were noted only in rats receiving carbon tetrachloride. Glomeruli were focally sclerotic with large electron-dense deposits within capillary lumina. Visceral epithelial cell injury was also frequently seen. Tubulointerstitial alterations were also more frequent in animals given carbon tetrachloride. Reduced renal mass may enhance the long-term nephrotoxicity of carbon tetrachloride.

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Seven cases of renal oncocytomas are described. Two cases were from recent surgical and autopsy material seen within a period of ten months. Four cases were reclassified as renal oncocytomas from a 20 year review of 63 renal cell carcinomas removed operatively. One case was identified from a nine year review of 31 renal cell carcinomas coded in our autopsy files. All patients were males; mean age was 69 years. The smallest tumor measuring 0.3 X 0.3 X 0.3 cm represents the smallest renal oncocytoma reported. The largest tumor weighed 2350 g. It is the largest renal oncocytoma so far reported in the literature. Two of the cases were found in polycystic kidneys. None of the seven patients presented with symptoms related to the tumors and the subsequent clinical course was benign in all cases. Differential diagnosis from renal cell carcinoma is discussed in terms of light and electron microscopic and radiologic aspects. The previously reported cases in the literature are reviewed.

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A method for initiating rapidly growing cultures of normal human transitional cells from ureter and embryonic bladder specimens has been developed and quantified. A new microdissection technique was used to nonenzymatically separate the urothelium. The use of enriched medium containing 10 micrograms/ml insulin, 5 micrograms/ml transferrin, and 1 microgram/ml hydrocortisone resulted in improved growth. The use of thin collagen gel substrates (0.6 ml/60 mm petri dish) resulted in 97% attachment of explants compared to 77% attachment on plastic. Explants grown on thicker collagen (2 ml/60 mm petri dish) showed, in addition to better attachment, enhanced growth of cells as determined both by measurements of colony size and cell density. Cultures of transitional cells that were initiated using explants could be passed three to five times using 0.1% EDTA for dispersion. Autoradiography of [3H]thymidine-labeled cells showed an initial phase of rapid cell division in primary explant cultures and restimulation of cell division in passaged cultures. Transmission electron microscopy showed that the cells growing out from the explants were continuous with the stratified urothelium maintained in the original explant. Stratification of transitional cells occurred in cultures of both ureter and embryonic bladder cells. Surface cells were joined near their apices by junctional complexes. Desmosomes and Golgi vesicles were present in all cells. Passage in culture did not alter the morphological characteristics of cells.

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This study describes the technique and instrumentation necessary to perform a double-wall biopsy of the endolymphatic sac (ELS). Since this technique protects the lumen of the ELS, which is within the center of the biopsy sample surrounded by the lateral and medial wall, the ultrastructure of the ELS epithelium, luminal contents, and perisaccular connective tissue tends to represent the in vivo status. The biopsy specimen can be analyzed by electron microscopy for clinical-pathologic correlation. Ultrastructural analysis (1) provides definite identification of the ELS and epithelium, (2) may provide insight into a possible role of the ELS in the pathogenesis of endolymphatic hydrops, and (3) can provide much improved clinical-pathologic correlation over only light microscopic studies.

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The ultrastructure of a case of rhabdomyosarcoma is reported, and the world literature on the ultrastructure of rhabdomyosarcomas is reviewed. The reported case was first observed as an undifferentiated malignancy originating in the maxillary antrum of a 46-year-old white woman and later showed differentiated cells in metastatic sites. A specific feature of the sarcomere within a representative malignant cell is necessary and sufficient for diagnosis of rhabdomyosarcoma by ultrastructure. Examples of specific features include thick and thin filaments in a hexagonal array, an unambiguous Z line, or A bands with H and M bands. The presence of thick and thin filaments without additional features of the sarcomere indicate a myogenous origin, either leiomyosarcoma or rhabdomyosarcoma. Other ultrastructural features observed in rhabdomyosarcomas, for which the diagnosis is confirmed by the presence of diagnostic ultrastructural features or by the presence of cross-striations observed by light microscopy, include large irregularly shaped nuclei with projections and invaginations, free ribosomes closely associated with filaments, rough endoplasmic reticulum that is often dilated, glycogen, and external lamina, prominent nucleoli, and pleomorphic mitochondria. When this spectrum of features is present, the possibility of rhabdomyosarcoma cannot be excluded, and a diligent search for the diagnostic components of the sarcomere should be made. Small intercellular junctions, pinocytotic vesicles, and paranuclear cilia occurred in the poorly differentiated metastasis of this case; the presence of these nonspecific features permits neither diagnosis nor exclusion of rhabdomyosarcoma.

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The metabolism and biliary excretion of 3H-2, 4, 5, 2', 4', 5'hexachlorobiphenyl (HCB) were studied in two rhesus monkeys (Macaca mulatta), a young, mature female and a juvenile male. This compound is a major constituent of those commercial polychlorinated biphenyl (PCB) mixtures with high chlorine content, and it is also a prevalent PCB analogue in human adipose tissue. Following cannulation of the common bile duct and duodenum, allowing collection of a known fraction of bile with return of the remaining bile into the duodenum, the animals received 3H-HCB (1 gm/kg body weight) by gastric intubation. Bile was collected daily for 3 weeks. During the 3-week period, 1.3% and 4% (from the female and male, respectively) of the administered radioactivity were excreted in the bile. As has been demonstrated for other species, the monkey apparently metabolizes and excretes HCB at a rate slower than for compounds containing two adjacent unsubstituted carbons. Approximately 2% of the bile radioactivity in the adult female and 12% in the juvenile male were extracted with organic solvents. Thin layer chromatography (TLC), using a benzene:ethyl acetate (12:1) solvent system, of the organic extracts of bile separated four major regions of radioactivity designated as I, II, II, and IV with Rf values of 0.86, 0.67, 0.58, and 0.00, respectively. Region I consisted of the parent HCB, which was identified by analysis with gas chromatography-mass spectrometry (GC-MS). Region II consisted of a metabolite identified as 2,4,5,2',4',5'-hexachloro-3-hydroxybiphenyl (OH-HCB) by analysis with GC-MS of the methylated derivative of the metabolite. Region III probably contained a more polar metabolite, which has not yet been identified. Region IV contained an even more polar material, probably including conjugates of HCB metabolites. Release of OH-HCB from the water-soluble fraction of bile in the presence of beta-glucuronidase and lack of release of OH-HCB in presence of beta-glucuronidase with saccharo-1, 4-lactone (a beta-glucuronidase inhibitor) or in the presence of aryl sulfatase with saccharo-1, 4-lactone provided evidence of water-soluble, glucuronic acid conjugates of OH-HCB in the bile. The hexachlorobiphenyl was excreted in the bile as HCB, OH-HCB, and water-soluble conjugates of HCB metabolites, probably including 2,4,5,2',4',5'-hexachloro-3-hydroxybiphenyl glucuronide. The metabolism of HCB may or may not include the formation of an arene oxide.

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A glomus tumor of the stomach was found in a 79-year-old white man who had episodes of upper gastrointestinal bleeding. Clinically, this uncommon gastric tumor mimics most of the benign and malignant lesions of the stomach. The most important aspect of this tumor, therefore, is its histologic identification and differentiation from the more common gastric lesions, most especially malignant tumors. This is of paramount importance because the glomus tumor is essentially benign and does not warrant a radical surgical procedure. The histologic and ultrastructural features of this particular gastric neoplasm are presented and discussed.

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Radiation-induced well-differentiated and poorly differentiated follicular thyroid cancers were transplanted into the intrascapular fat pads of male Fisher 144 rats. The tumors grew in the recipient rats and after a time interval were removed and studied along with normal rat thyroids for lysosomal activity and ultrastructural characteristics. Plasma from experimental and control rats was also studied for lysosomal activity. Rats with radiation-induced thyroid carcinoma had a decrease in growth rate compared with normal rats. There was no significant increase in plasma lysosomal enzymes in the experimental rats. Well-differentiated thyroid carcinomatous tissue showed increased total activities of lysosomal enzymes as well as a difference in subcellular distribution compared with normal and poorly differentiated carcinomatous tissue. Electron microscopy of normal and carcinomatous tissue demonstrated the greatest number of lysosomes in the well-differentiated carcinoma and the fewest in the poorly differentiated carcinoma.

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