Micro-concentrators for a microsystems-enabled photovoltaic system.

A 100X magnification, ± 2.5° field of view micro-concentrating optical system has been developed for a microsystems-enabled photovoltaic (MEPV) prototype module using 250 µm diameter multi-junction "stacked" PV cells.

The monkey safety test for neurovirulence of yellow fever vaccines: the utility of quantitative clinical evaluation and histological examination.

Two different derivatives of the 17D strain of yellow fever (YF) vaccine virus, i.e. ALV-free seed virus 6676 and three consecutive vaccine lots, A, B and C, obtained from another seed, were compared in monkey neurovirulence tests using rhesus and cynomolgus monkeys.

Rhesus diploid rabies vaccine (adsorbed): neurological safety in guinea pigs and Lewis rats.

Rabies vaccine produced in rhesus diploid cells (RDRV) and adsorbed on aluminium phosphate was evaluated for its neurological safety in guinea pigs and Lewis rats. The vaccine (as well as aluminium phosphate itself) in combination with myelin basic protein did not induce experimental allergic encephalomyelitis (EAE) when injected into either species. RDRV combined with complete Freund's adjuvant still failed to induce any signs of EAE.

Sensitization induced in guinea pigs with beta-propiolactone-treated serum albumin: experimental evidence for the cause of allergic reactions in humans receiving human diploid cell rabies vaccines.

beta-Propiolactone-treated (BPL-T) homologous serum albumin caused anaphylaxis in guinea pigs with a frequency and severity equal to that of guinea pigs inoculated with human albumin. Untreated guinea pig serum albumin did not cause any reactions in these animals. Some recipients of current rabies vaccine produced in human diploid cells available in the USA develop systemic allergic reactions, usually following booster immunization.

Tumorigenicity testing of primate cell lines in nude mice, muscle organ culture and for colony formation in soft agarose.

Primate neoplastic and finite cell lines were tested in one in vivo and two in vitro test systems: adult nude mice, muscle organ culture (MOC) and soft agarose (SA). Comparison of the sensitivity of the systems indicated that nude mice were inferior to either in vitro system: WI-38 VA13 (an SV40 transformed cell line) did not cause tumours in these animals yet it behaved as if it were neoplastic in MOC and formed colonies in SA. There was complete correlation between results obtained in MOC and SA.

Oral vaccination of monkeys with an invasive Escherichia coli K-12 hybrid expressing Shigella flexneri 2a somatic antigen.

A living oral vaccine, designed to protect against Shigella flexneri 2a infections, was constructed by using Escherichia coli K-12 as a carrier strain. The hybrid strain, designated EC104, contained both chromosomal and plasmid genes from S. flexneri donor strains.

Tumorigenicity of Vero cells.

One of the current criteria for evaluating the acceptability of cell lines for use in vaccine production is lack of tumorigenicity. Vero cells represent an example of a class of cells known as continuous cell lines. They were derived from African green monkey kidney, and their growth properties and culture characteristics have many advantages over other cell substrates for use in vaccine production.

Interferon fever: absence of human leukocytic pyrogen response to recombinant alpha-interferon.

A sensitive in vitro assay for generation of human leukocytic pyrogen has been used to study the pathogenesis of fever accompanying administration of human alpha-interferon. Unlike other potent pyrogens, two recombinant interferon preparations tested over a wide concentration range did not stimulate release of leukocytic pyrogen. This result suggests that interferon may cause fever by a novel mechanism not dependent on leukocytic pyrogen.

Epidemic typhus in the United States associated with flying squirrels.

Between July 1977 and January 1980, seven cases of sporadic, nonepidemic "epidemic" typhus (Rickettsia prowazekii) were discovered in Virginia, West Virginia, and North Carolina. The reservoir seemed to be the southern flying squirrel (Glaucomys volans), an animal indigenous to the eastern United States; however, the vector or mode of acquisition was not evident. Diagnosis was established principally through complement fixation, indirect immunofluorescence, and toxin neutralization tests.

Experimental infection of ectoparasitic arthropods with Rickettsia prowazekii (GvF-16 strain) and transmission to flying squirrels.

Epizootiologic studies conducted during the past few years showed the existence of widespread natural infection of the southern flying squirrel, Glaucomys volans, with epidemic typhus rickettsiae, Rickettsia prowazekii. The ecological findings strongly implicated transmission of the etiologic agent by an arthropod vector. Studies were conducted under controlled laboratory conditions to determine whether ectoparasites naturally associated with flying squirrels (squirrel fleas, lice, mites and ticks) were capable of acquiring, maintaining and transmitting the infection.

Enhancement of carcinoembryonic antigen expression by interferon.

Human interferon decreased DNA but not RNA synthesis in a human colon carcinoma cell line, WiDr; in addition, there was a two- to three-fold increase in the expression of a tumor-associated antigen, carcinoembryonic antigen. In contrast, interferon had no effect on a normal human diploid cell line, WI-38. Thus, in addition to its anti-cellular effect against tumor cells, interferon can also modulate tumor antigenicity.

Epizootiology of epidemic typhus (Rickettsia prowazekii) in flying squirrels.

Vector transmission of Rickettsia prowazekii among wild flying squirrels, Glaucomys volans, was suggested by the occurrence of natural infection of squirrel lice and fleas. Lice, mostly Neohaematopinus sciuropteri Osburn, were found infected in the fall in each of 2 consecutive years; 4 of the 8 pools of this insect tested were infected. Fleas, Orchopeas howardii (Baker), were found infected on two occasions in 1 of the 2 consecutive years.

Evaluation ofprimary blood monocyte and bone marrow cell culture for the isolation of Rickettsia rickettsii.

Rickettsia rickettsii was isolated from experimentally infected guinea pigs by culture of blood monocytes and bone marrow cells, and from experimentally infected rhesus monkeys by blood monocyte culture. Rickettsiae were identified in monocyte-macrophage monolayers stained by Giménez or flourescent antibody techniques. A total of 78 culture attempts were made from 20 guinea pigs and 16 monkeys.

Isolation of Rickettsia rickettsi in primary bone marrow cell and circulating monocyte cultures derived from experimentally infected guinea pigs.

Rickettsia rickettsi was isolated and propagated in primary cell cultures derived from experimentally infected guinea pigs. Organisms were recognized as early as 3 days after cultures were initiated.

Zoonotic infections in military scout and tracker dogs in Vietnam.

Significant levels of antibodies indicative of a variety of zoonotic infections were demonstrated in sera collected from 64 U.S. military scout and tracker dogs after service in the Republic of Vietnam (RVN).