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Thirty-six adult patients with classical hyperparathyroidism had parathyroidectomy in which tissue evaluation included oil red O stains. Neutral lipid staining has been reported to distinguish hyperfunctioning parathyroid from suppressed or normal tissue. In normal glands, parathyroid chief cells show abundant coarse and fine intracytoplasmic neutral lipid droplets. In contrast, the cytoplasm of chief cells is essentially free of neutral lipid droplets in adenomatous, hyperplastic, or carcinomatous glands. This study shows that to limit or alter surgical exploration solely on the basis of the findings of the oil red O technique will lead to significant judgmental error (6/36 patients). Such errors are especially likely in the patient who has enlarged parathyroid glands containing a normal distribution of parenchymal to adipose tissue. There was excellent agreement between clinical outcome, surgical-pathological findings, and the oil red O stain in 30 cases of parathyroid adenoma, nodular hyperplasia, and a control group (12 patients) who had biopsies of normal parathyroid tissue during the course of thyroidectomy.

Three adrenal medullary tumors that showed admixtures of pheochromocytomatous elements with ganglioneuroma or ganglioneuroblastoma were studied to determine the distribution of immunoreactive chromogranins, S-100 protein, and vasoactive intestinal peptide (VIP). Two tumors consisted of typical pheochromocytoma cells admixed with mature-appearing ganglioneuroma. The third consisted of pheochromocytoma admixed with ganglioneuroblastoma and contained many immature and cytologically atypical cells. In all cases, chromogranin staining was absent or weak in neuronal perikarya and moderate to intense in varicosities of neuronal processes, a finding consistent with the presumed distribution of secretory granules in neurons. Chromogranin staining was also intense in chromaffin cells. Glial cells that stained for S-100 were randomly scattered among chromaffin cells but accumulated in areas with neuronal processes. Weak staining for VIP was present in neuronal cells in one of the two tumors with ganglioneuromatous features. Intense staining for VIP occurred in the third tumor in both neuronal and apparently nonneuronal cells. We conclude that granule distribution and cell-cell interactions for specific cell types in compound tumors tend to mimic those in normal adrenal medulla and sympathetic ganglia. Although immunoreactive VIP was localized exclusively to neurons in one tumor, as in normal tissues, patterns of staining for VIP across tumors are less predictable.

A histochemical technique, developed for the localization of DHO-D activity in tissue, has been utilized to study the distribution of this activity in rabbit spleen. This enzyme is involved in the de novo synthesis of pyrimidines of nucleic acids via orotic acid as an intermediate. The enzyme was found to be most active at the periphery of follicles in the resting spleen. Following antigenic challenge, enzyme activity became prominent for several days in macrophages within germinal centers, but not in the intensely pyroninophilic cells which are the dominant cell type of these structures. Antigenicity of the injected compound appeared to be necessary for the production of this effect. The pattern of localization of DHO-D is similar to the pattern of distribution of antigen within splenic tissue.

Temporary crowns with subgingival margins can result in gingival inflammation. This inflammation is the result of plaque accumulating at the restoration-tooth interface and a change in the nature of that plaque to one associated with periodontitis. It was postulated that tetracycline incorporated in a slightly soluble cement would be released in the sulcus and decrease the amount, and improve the quality, of the subgingival microflora. The unknown was whether tetracycline is inactivated by any of the components of the temporary cement Temp Bond. To determine this concern, disks of Temp Bond cement with and without varying concentrations of tetracycline were anaerobically incubated in cultures of Bacteroides gingivalis. Results showed that tetracycline incorporated in Temp Bond at 10% by weight is highly bacteriostatic while retaining typical working properties of the cement.

Continuous monitoring of the electrocardiogram provides an opportunity for the veterinary surgeon to perform the surgical procedure in a safe and controlled manner. Arrhythmias can usually be eliminated by lowering the concentration of anesthetic and administering additional oxygen. Antiarrhythmic drugs are required when these measures do not control the problem and when surgery cannot be stopped. If a disturbance cannot be abolished or controlled with medication, the surgeon must weigh the potential gain of surgery against the potential risks of the arrhythmia.

We used micrococcal nuclease to separate murine erythroleukemia cell (MELC) chromatin into soluble and insoluble fractions which differ in gene content and chromatin structure. Genes that are not expressed in the erythroid lineage, such as the Ig alpha and albumin genes, distribute preferentially into the soluble rather than the insoluble fraction, and are organized into nucleosomes in both fractions. Both alpha 1- and beta maj-globin genes are enriched in the insoluble fraction and are organized into structures that are partially devoid of nucleosomes in uninduced MELC, when the genes are transcriptionally inactive. Following chemical induction of MELC and the onset of globin gene transcription, globin gene enrichment and nucleosome disruption in the insoluble chromatin fraction increase. Using seven DNA subclones that span the beta maj-globin gene we show that insolubility and nucleosome disruption are largely limited to DNA sequences lying within the transcribed domain. Non-transcribed, flanking sequences are soluble and organized into nucleosomes. In addition, the globin genes found in insoluble, non-nucleosomal chromatin contain previously engaged RNA polymerases which can elongate globin RNA chains in vitro in a pattern qualitatively and quantitatively similar to intact nuclei. These results are discussed in terms of a model for globin gene activation during erythropoeisis.

The extent of the surgical resection necessary for breast cancer patients treated by primary radiation therapy is unknown. A simple gross excision of the tumor provides the best cosmetic result, but a wide local resection may be important to prevent local recurrence in some patients. In order to identify patients who are not adequately treated by gross excision of the tumor and radiation therapy, we performed a retrospective clinical-pathologic review of 221 treated women with infiltrating duct carcinoma. There were 53 cases in which the excision specimen showed a constellation of three pathologic features: prominent intraductal carcinoma in the tumor, intraductal carcinoma in the grossly-normal adjacent tissue, and poorly-differentiated nuclei. These cases had a 37% risk of a local recurrence at 6 years compared to eight per cent for all other cases (p less than 0.0001). In cases with all three features, the use of a supplemental dose of radiation to the primary site did not significantly reduce the risk of a local recurrence. Local recurrence at 6 years was 34% in cases with all three features, who received supplemental local radiation, compared to 49% in cases not receiving a supplemental dose (p = 0.28). Survival was also worse for patients with all three features compared to other cases (69% vs. 90% at 6 years, p = 0.002). These results indicate that patients with all three pathologic features have a high risk of local recurrence following gross excision of the tumor and radiation therapy. If primary radiation therapy is selected for these patients, they should first undergo a re-excision of the tumor site in order to be certain that areas of extensive intraductal carcinoma have been adequately resected. Patients whose tumors do not show all three features are adequately treated by gross excision of the tumor prior to radiation therapy.

A patient with a fistula producing a 2:1 left-to-right shunt between the coronary arteries and pulmonary artery followed for 13 years is described. The patient remained asymptomatic and without significant electrocardiographic, hemodynamic, or angiographic changes. Large collateral vessels were demonstrated on initial and repeat angiographic studies. This case illustrates the natural history of coronary artery to pulmonary artery shunts and suggests that surgery may not be necessary, even in the presence of a very large communication.

Thirty-six postirradiation breast tissue specimens from 30 patients with breast cancer treated by primary radiation therapy were evaluated to define the effects of therapeutic doses of ionizing radiation on the residual non-neoplastic breast tissue. Breast tissue was sampled an average of 30.4 months after completion of therapy because of the development of new clinically or mammographically detectable abnormalities within the treated breasts. The average radiation dose was 6,399 rad to the primary tumor area and 4,778 rad to the remainder of the breast. Breast tissue sections from 35 nonirradiated patients served as control specimens. The most characteristic radiation effects consisted of atypical epithelial cells in the terminal duct lobular unit ( TDLU ) associated with lobular sclerosis and atrophy. These changes were present in all of the irradiated patients but varied in severity and extent among patients and within individual patients. This variation was not related to the presence or absence of carcinoma elsewhere in the specimen, radiation dose, patient age, time to postirradiation tissue sampling, or use of adjuvant chemotherapy. Epithelial atypia in larger ducts, stromal changes, and vascular changes were less frequent but were always accompanied by prominent TDLU changes. Radiation effects could usually be clearly distinguished from carcinoma involving the TDLU by the absence of both cellular proliferation and distention of the involved TDLU and by the preservation of cellular polarity and cohesion in areas of presumed radiation-induced injury. Familiarity with these changes is of considerable practical importance in that they must be distinguished from new or recurrent neoplasms.

We have recently cloned and characterized the promoter region of the gene encoding eukaryotic initiation factor 2 alpha (eIF-2 alpha) to identify regulatory elements of this housekeeping gene. We compared the location of DNase I-hypersensitive (HS) sites with the distribution of protein-binding sites as revealed by footprint analysis. The eIF-2 alpha promoter contains four upstream DNase I-HS sites extending from -650 to -40 base pairs and a fifth downstream site near the first intron-exon junction. In vitro DNase I footprint analysis shows eight distinct DNA-protein interactions organized into clusters that correspond well with the distribution of the five HS sites. None of the protected regions, however, shares obvious sequence homology with the binding sites of known regulatory factors. To initiate our analysis of factors required for eIF-2 alpha expression, selected a CAP-proximal element shown by in vivo methylation protection analysis to bind a potential regulatory factor. A striking feature of this element is its palindrome sequences and eight-base pair direct repeats. We have purified to near homogeneity a 66-68-kDa protein that binds to this region and have designated it alpha-PAL. The alpha-PAL-binding site extends from -74 to -10. By methylation protection analysis and mobility shift assay, the alpha-PAL-binding site is shown to be two adjacent sites, one with high and one with lower affinity, which bind alpha-PAL in a noncooperative manner. When the high affinity binding site is cloned upstream of the adenovirus 2 core promoter, in vitro transcription is stimulated 2-3-fold. When linked to a CAT reporter gene, activity of the eIF-2 alpha promoter shows an approximate 2-fold dependence on the alpha-PAL element.

An ultrasensitive detection method for atmospheric monitoring has been developed based on the technique of supersonic molecular beam, resonance enhanced multiphoton ionization, and time-of-flight mass spectroscopy (MB/REMPI/TOFMS). Several organophosphonate and organosulfide compounds, representing simulants to a class of toxic compounds, were studied. Detection levels as low as 300 ppt (dimethyl sulfide) were obtained. Single-vibronic-level REMPI of the cooled molecules in conjunction with TOFMS provided selectivity of ~10(4) against chemically similar compounds in humid air expansions. The fragment ions formed by REMPI excitation are shown for diisopropyl methylphosphonate to depend strongly on the resonant intermediate state of the neutral molecule.

The promoter region of the gene (eIF-2 alpha) for eukaryotic initiation factor 2 alpha (eIF-2 alpha) was isolated from a human genomic library and its structure was determined by restriction mapping and nucleotide (nt) sequence analysis. The promoter region and twelve in vivo transcriptional start points (tsp) have been identified by endonuclease S1 mapping and their location confirmed by primer-extension analysis, using RNA isolated from human cells. The untranslated leader is 102 to 140 nt long depending upon the tsp, and the 5' region of the mRNA has the potential for forming stable stem-loop structures. The nt sequence of the regions upstream and downstream from the tsp contains neither a 'TATA box' nor a 'CAAT box', but does contain several direct and inverted repeats, as well as palindromic sequences near the tsp. In addition, multiple consensus binding sites for a wide variety of regulatory proteins are present throughout upstream and downstream tsp-flanking regions.