Characterization of a picosecond gated optical intensifier.

The development of high speed imaging detectors is crucial for high-temperature plasma characterization and optimization. These detectors must perform within many strict parameters, such as precise timing, high spatial resolution, low noise, high gain, and fast gating. We present test results on a picosecond gated optical intensifier that aims to meet these requirements. The detector was developed by Kentech and is part of a packaged Sydor solution of 1-8 detectors, designed for use in plasma diagnostics. It has low jitter (SD 4 ps) and gate widths less than 80 ps. We use a pulsed laser to test the gate profile and the spatial resolution performance of the intensifier at different points within the gate.

Advantages of environmental scanning electron microscopy in studies of microorganisms.

Microorganisms, including bacteria, fungi, protozoa, and microalgae, are composed predominantly of water which prohibits direct observation in a traditional scanning electron microscope (SEM). Preparation for SEM requires that microorganisms be fixed, frozen or dehydrated, and coated with a conductive film before observation in a high vacuum environment. Sample preparation may mechanically disturb delicate samples, compromise morphological information, and introduce other artifacts. The environmental scanning electron microscope (ESEM) provides a technology for imaging hydrated or dehydrated biological samples with minimal manipulation and without the need for conductive coatings. Sporulating cultures of three fungi, Aspergillus sp., Cunninghamella sp., and Mucor sp., were imaged in the ESEM to assess usefulness of the instrument in the direct observation of delicate, uncoated, biological specimens. Asexual sporophores showed no evidence of conidial displacement or disruption of sporangia. Uncoated algal cells of Euglena gracilis and Spirogyra sp. were examined using the backscatter electron detector (BSE) and the environmental secondary electron detector (ESD) of the ESEM. BSE images had more clearly defined intracellular structures, whereas ESD gave a clearer view of the surface E. gracilis cells fixed with potassium permanganate, Spirogyra sp. stained with Lugol's solution, and Saprolegnia sp. fixed with osmium tetroxide were compared using BSE and ESD to demonstrate that cellular details could be enhanced by the introduction of heavy metals. The effect of cellular water on signal quality was evaluated by comparing hydrated to critical point dried specimens.

Primary pulmonary botryomycosis. A manifestation of chronic granulomatous disease.

A 19-year-old woman with a childhood history of cavitating left upper lobe pneumonia presented with persistent weight loss, fever, cough and roentgenographic evidence of right upper lobe pneumonia resistant to antibiotic therapy. An open lung biopsy led to the diagnosis of botryomycosis. Neutrophil function studies including flow cytometric evaluation of oxidative burst, bacterial killing and evaluation of neutrophil cytosolic proteins required for oxidase activation were consistent with chronic granulomatous disease. This is the first case report of primary pulmonary botryomycosis as a clinical manifestation of CGD. Other recent cases of immunodeficiency states associated with botryomycosis are reviewed.

Submandibular cystic hygroma resembling a plunging ranula in a neonate. Review and report of a case.

Cystic hygromas are large lymphangiomas that are most often found in the posterior triangle of the neck and the axilla in children. They are most frequently found before age 2 and may be massive. After upper respiratory infection, they may become infected and enlarged, causing dysphagia and toxemia. The diagnosis can usually be made by history and physical examination and confirmed by biopsy. Treatment is by surgical excision of small lesions and staged debulking excisions in more severe cases. A patient with a cystic hygroma having many clinical characteristics of a plunging ranula is presented. The cyst fluid was aspirated and analyzed for its amylase, sodium, potassium, chloride, urea nitrogen, glucose, and total protein content. The characteristics of the fluid were also compared with those of lymph and saliva. This report demonstrates the difficulty in determining the diagnosis of a tumor that has the clinical features of a cystic hygroma, as well as a plunging ranula. The necessity of a proper presurgical diagnosis is essential since the form of therapy for each is different and conflicting. A method that distinguishes between the cervical cystic hygroma and a plunging ranula by means of aspirated fluid is discussed.

Kaposi's sarcoma with bone marrow involvement: occurrence in a patient with the acquired immunodeficiency syndrome.

A patient with the acquired immune deficiency syndrome (AIDS) and the lymphadenopathic variant of Kaposi's sarcoma developed skin, gastrointestinal and pulmonary lesions. A cellular specimen was obtained on bone marrow aspiration, but the bone marrow biopsy revealed dense reticulin fibrosis with slit-like spaces and endothelial-lined channels consistent with Kaposi's sarcoma. At postmortem examination, Kaposi's sarcoma was found in the pleura and lungs, throughout the gastrointestinal tract, in the liver and spleen, and in the thoracic and abdominal lymph nodes. Bone marrow architecture appeared grossly normal, but microscopic examination revealed numerous foci of Kaposi's sarcoma. This is the first reported example of bone marrow involvement with Kaposi's sarcoma in AIDS recognized antemortem.