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Biomedical subjects

F B Johnson

Publications and source records attributed to F B Johnson.

At least 55 records · Page 3Linked to original sources
PubMed1990

Teflonomas of the larynx and neck.

Intracordal fluorocarbon (Teflon, Mentor O and O Inc, Norwell, MA) injection has been used for decades to correct paralytic dysphonia, a result of unilateral laryngeal paralysis. Infrequently, the Teflon extravasates and infiltrates into the soft tissues of the neck and larynx producing a mass that clinically simulates a malignant lesion. We report eight cases of so-called "Telonomas" of the larynx and neck that have been identified in the files of the Armed Forces Institute of Pathology Otolaryngic Tumor Registry and from the Cytopathology Service at the George Washington University Medical Center. Patients ranged in age from 31 to 72 years. Vocal cord paralysis, treated by Teflon injection, was caused by primary laryngeal carcinoma or metastatic carcinoma (breast, lung) involving the recurrent laryngeal nerve, surgical trauma to the recurrent laryngeal nerve, or postviral neuritis. Subsequent symptomatology, related to extravasation of the Teflon with a resulting "Teflonoma", included a neck mass or persistent hoarseness. Infrequently, there was associated airway obstruction or voice changes. Diagnosis was made by fine needle aspiration or by excision of the suspicious mass and subsequent identification of a foreign body granulomatous reaction with associated birefringent material. Infrared absorption spectrophotometry identified the foreign material as a fluorocarbon which was further substantiated by scanning electron microscopy and energy dispersive x-ray analysis. Surgical removal of the mass alleviated all symptoms.

Adult↗
PubMed1990

The nature of hyaline (eosinophilic) globules and vascular slits of Kaposi's sarcoma.

Ultrastructural studies of Kaposi's sarcoma (KS) from skin biopsies of 24 patients (eight with acquired immunodeficiency syndrome (AIDS) and 16 without) were performed to delineate the nature of hyaline globules and vascular slits. These structures have been regarded as one of the important criteria for the recognition of KS under light microscopy. Histochemical and immunochemical studies were also performed to correlate with the electron microscopic (EM) observations. The most remarkable EM findings of KS were the intracytoplasmic lumen formation and erythrophagocytic activities of the neoplastic cells, particularly in the mature nodular, or neoplastic stage. The spindle-shaped or ovoid neoplastic cells frequently contained one to several intact and fragmented red blood cells. The intracellular and extravasated erythrocytes were often arranged in single files, giving these vascular slits an elongated appearance on longitudinal sections. The phagocytic activities of the neoplastic cells were demonstrated by the presence of membrane-bound lysosomes containing phagocytized erythrocytes and their partially digested forms (erythrophagosomes) adjacent to pinocytotic vesicles, prominent rough endoplasmic reticulum, and Golgi apparatus, as well as scattered, small, membrane-bound lysosomal granules, some of which were attached to the erythrophagosomes. The erythrophagosomes underwent various stages of disintegration. The partially digested red cells varied from 0.4 to 10 microns in diameter. The results of histochemical and immunochemical findings also strongly suggested that erythrophagosomes were most likely the hyaline globules (bodies) seen in light microscopy. The exact mechanism of erythrophagocytosis is uncertain. However, its consequences, erythrophagosomes, and intracytoplasmic lumen formation, particularly in the nodular or neoplastic stage in patients with and without AIDS, are among the important histologic features of KS.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Stimulation of transcription by an Ultrabithorax protein in vitro.

The Ultrabithorax (Ubx) gene of Drosophila melanogaster encodes a family of UBX proteins that are thought to specify the developmental fates of segments in the posterior thorax and anterior abdomen by controlling the expression of a set of target genes. UBX proteins bind DNA in vitro, and they activate or repress different natural and synthetic target promoters in cultured cells. Here it is shown that a purified UBX protein can stimulate transcription of a synthetic target gene in extracts of cultured D. melanogaster cells. Stimulation is dependent on the presence of upstream, promoter-region binding sites but is independent of binding site orientation. A naturally occurring binding site cluster and a binding site consensus sequence consisting of TAA trinucleotide repeats can mediate this activation. A minimal promoter fused to such sites is activated by UBX, suggesting that transcriptional stimulation could result from an interaction between the promoter-bound protein and the general transcriptional machinery.

Animals↗
PubMed1990

Transport of viral specimens.

The diagnosis of viral infections by culture relies on the collection of proper specimens, proper care to protect the virus in the specimens from environmental damage, and use of an adequate transport system to maintain virus activity. Collection of specimens with swabs that are toxic to either virus or cell culture should be avoided. A variety of transport media have been formulated, beginning with early bacteriological transport media. Certain swab-tube combinations have proven to be both effective and convenient. Of the liquid transport media, sucrose-based and broth-based media appear to be the most widely accepted and used. Studies on virus stability show that most viruses tested are sufficiently stable in transport media to withstand a transport time of 1 to 3 days. Some viruses may withstand longer transport times. In many cases, it is not necessary to store virus specimens in a refrigerator or send them to the laboratory on wet ice or frozen on dry ice. However, the specimen should not be exposed to environmental extremes. Modern viral transport media allow for more effective use of viral culture and culture enhancement techniques for the diagnosis of human viral infections.

Culture Media↗
PubMed1988

Lycopodium granuloma.

The spores of Lycopodium (L) clavatum were used as a component of a dusting powder in many hospitals during the 1920's and 1930's. When L spores enter surgical wounds a lesion clinically resembling tuberculosis or neoplasia may develop months or even years later. We recently encountered a case of L granuloma occurring in a patient 50 years after an appendectomy. Three additional cases found in the files of the AFIP are also reported.

Aged↗
PubMed1987

Liesegang rings in tissue. How to distinguish Liesegang rings from the giant kidney worm, Dioctophyma renale.

Liesegang rings (LRs) are periodic precipitation zones from supersaturated solutions in colloidal systems. They are formed by a process that involves an interplay of diffusion, nucleation, flocculation or precipitation, and supersaturation. Examples include LRs of calcium carbonate in oölitic limestone (in nature), LRs of silver chromate in gelatin (in vitro), and LRs of glycoprotein in pulmonary corpora amylacea (in vivo). Here we describe LRs in lesions from 29 patients--mostly lesions of the kidney, synovium, conjunctiva, and eyelid. The LRs formed in cysts, or in fibrotic, inflamed, or necrotic tissue. The LRs in this study varied greatly in shape and size, measuring 7-800 microns. Special stains and energy-dispersive radiographic analysis or scanning electron microscopy revealed that some LRs contained calcium, iron (hemosiderin), silicon, and sulfur. Some pathologists have mistaken LRs for eggs, larvae, or adults of the giant kidney worm, Dioctophyma renale. D. renale is a large blood-red nematode that infects a variety of fish-eating mammals, especially mink. Fourteen documented infections of humans have been recorded, usually with adult worms expelled from the urethra. The adult worms are probably the largest helminth to parasitize humans. Eggs of D. renale are constant in size (60-80 microns X 39-47 microns), contain an embryo, and have characteristic sculpturing of the shell. Liesegang rings should not be mistaken for eggs, larvae, or adults of D. renale, or for any other helminth.

Chemical Precipitation↗
PubMed1986

Suitability of new chlamydia transport medium for transport of herpes simplex virus.

A new chlamydia transport medium (ChlamydiaPort; Scott Laboratories, Inc., Fiskeville, R.I.) was evaluated for its suitability as a transport medium for herpes simplex virus (HSV). Two laboratory HSV strains (McIntyre and 333) and two clinical isolates (AO218 and AO301) were suspended in ChlamydiaPort, ViraPort (Scott Laboratories), and cell culture medium and maintained at 2 and 22 degrees C. Samples were tested at various time intervals to determine surviving virus. The range of half-lives of the HSV strains held at 2 degrees C in ChlamydiaPort medium was from 3.5 to 10 days, while virus stability was greater in ViraPort and less in cell culture medium. These HSV strains held at 22 degrees C in ChlamydiaPort had half-lives from 1.5 to 6 days, which were significantly greater than the half-lives of the viruses held in either tissue culture medium or ViraPort. Clinical specimens were tested for virus by using the Selecticult-HSV (Scott Laboratories) system to determine the performance of the transport medium under field conditions. Clinical specimens maintained up to 5 days at ambient temperatures in ChlamydiaPort medium appeared suitable for diagnostic testing without detectable loss of positive specimens. In addition, there was a significant decrease in the average time required for diagnosis when compared with a standard transport system, Virocult (Microdiagnostics, Cleveland, Ohio). These results show that HSV infections can be successfully diagnosed in distant virology laboratories by shipping specimens in ChlamydiaPort transport medium at ambient temperatures.

Chlamydia↗
PubMed1986

Identification and significance of magnetite in human tissues.

Magnetite or iron oxide has been identified in humans as well as certain animals and bacteria. With the current popularity of magnetic resonance imaging, the presence of these ferromagnetic particles in the tissues may impose biological significance. So far, identification of magnetite in tissue has been mainly based on magnetometry. Hence, a simple technique for direct identification of the magnetic particles in tissues is described. Lung tissues with abundant iron material and particles were digested in 1N sodium hydroxide solution. After rinsing, the sediments were suspended in 95% alcohol and placed on a glass slide located on a strong magnet. The iron-containing particles from the digestion procedure were aligned in a parallel manner along the north-south poles of the magnet and were confirmed to be magnetite by x-ray diffraction. No such effect was observed with hemosiderin-containing granules from the control liver tissues. The results of this experiment show that the "biological magnetite" is distinctly different from hemosiderin and has characteristic properties when subjected to a magnetic field.

Adult↗
PubMed1985

Sodium orthophosphate hydrate (NA3PO4.12H2O): a new type of human urinary stone.

In a series of electron microscopic studies of human urinary stones, a stone composed of sodium orthophosphate hydrate was identified. The stone was recovered from a patient who succumbed to advanced renal failure. A massive failure of the sodium pump, which cotransports phosphate across the brush border membrane of the proximal tubules is thought to be responsible for such an exceptional stone. This appears to be the first description of sodium phosphate crystal in a human urinary stone. Electron microscopy is a useful tool for stone analysis.

Aged↗
PubMed1985

Modified radical neck dissection and postoperative radiotherapy in squamous cell head and neck cancer.

Between 1978 and 1982, 41 patients with clinically staged N1, N2, or N3b disease underwent unilateral or bilateral modified radical neck dissection. Five patients died free from their original disease with less than 24 months follow-up. Twenty-four patients with histologically positive nodes received postoperative radiotherapy with 2 (8 percent) neck recurrences. Another four patients with histologically positive nodes refused postoperative radiotherapy and had two (50 percent) neck recurrences. Three patients did not respond to radiotherapy at the time of their surgery and had no neck recurrences. The final five patients had histologically negative nodes, did not receive radiotherapy, and had no neck recurrences. These results suggest that modified radical neck dissection can be used in lieu of the classical radical dissection in many patients with clinically positive nodes who have squamous cell head and neck cancer without compromising survival.

Carcinoma, Squamous Cell↗
PubMed1985

Amyloid plaques in spongiform encephalopathy of mule deer.

Amyloid plaques were demonstrable in central nervous system tissues of adult captive mule deer affected with chronic wasting disease, a transmissible primary spongiform encephalopathy. Plaques were detected in tissues of 13 of 21 (62 per cent) spontaneously affected animals from 2 to 4 years of age or older, but were not found in 16 unaffected deer of from a few months to 12 years of age.

Age Factors↗
PubMed1985

A prospective study of preoperative chemotherapy and split-course irradiation for locally advanced or recurrent oral/pharyngeal squamous carcinoma.

Two courses of preoperative chemotherapy (methotrexate, bleomycin, cisplatin) were combined with split-course irradiation (2,000 rad/10 preop., 4,000 rad/20 postop.) and prospectively compared with standard therapy (surgery and/or irradiation alone) for locally advanced or recurrent oral/pharyngeal squamous cancer. The chemoradiotherapy arm (Ch-XRT) had 31 patients; the standard therapy arm 28 randomized (RC) and 20 concomitantly-treated (CC) patients. Treatment-related mortality was 17% for Ch-XRT; 10% for RC + CC. Number of patients NED at completion of treatment was 74% for Ch-XRT; 83% for RC + CC (NS). Median survival, however, was 17 months for Ch-XRT, 9 months for CC, and 12 months for RC. In addition, survival at 40 + months was 45% for Ch-XRT versus 21-22% for RC and CC (p less than 0.05). Thus, Ch-XRT seems to have promise in advanced oral/pharyngeal cancer, but needs revision to decrease toxicity.

Aged↗
PubMed1985

Comparison of the Scott Selecticult-HSV kit with conventional culture and direct immunoperoxidase staining for detection of herpes simplex virus in cultures of clinical specimens.

In a comparative study, clinical specimens were cultured for herpes simplex virus (HSV). The presence of virus was noted by the appearance of characteristic cytopathic effect, as determined by standard direct immunofluorescence techniques, by using a direct immunoperoxidase stain for viral antigen, or by using the Selecticult-HSV (SC-HSV) stain for viral antigen. There was 100% correlation between the SC-HSV stain and immunofluorescence staining in recognizing HSV-infected cells (81 of 81 positive specimens). In comparison with observation of cytopathic effect, the SC-HSV system and conventional culture detected 93 and 78% of positive cultures at 48 h postinoculation and 76 and 32%, respectively, at 24 h. By 5 days postinoculation, SC-HSV detected 100% of the positive specimens. As compared with the direct immunoperoxidase stain, SC-HSV stain was slightly more sensitive and gave less background stain. HSV serotypes 1 and 2 were both detected by the SC-HSV stain. The Scott SC-HSV kit appears to be an effective system for the diagnosis of HSV infections.

Antigens, Viral↗
PubMed1985

Comparison of an avidin-biotin immunoassay with three commercially available immunofluorescence kits for typing of herpes simplex virus.

An avidin-biotin complex system was compared with three commercially available immunofluorescence kits for serotyping herpes simplex virus isolates from clinical specimens. Sensitivity values showed that the Electro-Nucleonics and Immulok reagents were useful in detecting the presence of virus, whereas the predictive values showed that the Syva and Immulok reagents possessed adequate discrimination between the herpes simplex virus serotypes. The avidin-biotin complex system was equal or superior to the immunofluorescence reagents tested both in detecting herpes simplex virus antigens in cell culture and in serotyping herpes simplex virus isolates.

Antigens, Viral↗
PubMed1985

X-ray microanalysis of urinary stones, a comparison with other methods.

A previous study of urinary stones by a combined electron microscopy demonstrated the potential of scanning electron microscopy and X-ray analysis as an analytic tool for urinary stones. Electron diffraction was chosen for the final confirmation of crystals in the study. Although electron diffraction is highly accurate for this purpose, it is desirable to establish the sensitivity of X-ray analysis for the identification of stone components relative to the more commonly used methods. Eighty six consecutive urinary stones were analyzed by X-ray analysis and the findings were compared with those of X-ray diffraction, infrared spectrometry and chemical analysis. The results indicate that X-ray analysis exceeds X-ray diffraction and infrared spectroscopy in its sensitivity for the identification of stone components several fold. This was largely due to the inability of the latter methods to detect apatite in more than half of the apatite containing stones. The findings in X-ray analysis had the best correlation with chemical analysis, which was applied mainly to the detection of apatite. X-ray analysis is particularly suited for the detection of rare and minor inorganic components of urinary stones such as silica and gypsum, and is obviously one of the most powerful tools for the analysis of urinary stones. Further application of X-ray analysis to urinary stone is likely to discern rare inorganic components of urinary stones overlooked by other methods.

Calcium Oxalate↗