Cultured Chinese hamster cells undergo apoptosis after exposure to cold but nonfreezing temperatures.

Cultured Chinese hamster V79 fibroblast cells at the transition from logarithmic to stationary growth have been shown to undergo apoptosis (programmed cell death) after cold shock [B. L. Soloff, W.

Apoptosis induced by cold shock in vitro is dependent on cell growth phase.

Chinese hamster V79 fibroblast cells were exposed to brief periods of cold but non-freezing temperatures at different points on the population growth curve. Upon rewarming, cells at the transition from logarithmic to stationary growth exhibited apoptosis (programmed cell death). Cells in other stages of growth, or after reentry into logarithmic growth by refeeding, did not exhibit apoptosis.

Electron microscopic observations concerning the in vivo uptake and release of the agent of guinea-pig inclusion conjunctivitis (Chlamydia psittaci) in guinea-pig exocervix.

This report details electron-microscopical observations concerning C. psittaci infection in vivo. The model employed was that of the guinea-pig infected at the exocervical region with the agent of guinea-pig inclusion conjunctivitis (GPIC).

Treatment of varicella-zoster meningoencephalitis with acyclovir--demonstration of virus in cerebrospinal fluid by electron microscopy.

Disseminated varicella-zoster (V-Z) infection developed in three immunocompromised patients, with direct invasion of the central nervous system by virus. For two of these patients, diagnosis was confirmed by electron microscopic examination of cerebrospinal fluid (CSF) and detection of viral particles. Extensive immunologic evaluation demonstrated impairment of cellular immune function.

Cystitis associated with chlamydial infection of the genital tract in male guinea pigs.

Male guinea pigs were infected with the chlamydial agent of guinea pig inclusion conjunctivitis (GPIC) by intraurethral injection of chlamydiae or by placement of a drop of chlamydial suspension on the meatus of the extruded penis. Transient urethritis and cystitis were observed in animals infected by either method. The production of cystitis by the drop-on technique indicated that chlamydiae are able to ascend the urethra and that the bladder may be a target organ of chlamydial infection.

A new animal model for the study of Chlamydia trachomatis genital infections: infection of mice with the agent of mouse pneumonitis.

A new animal model for the study of genital infections caused by Chlamydia trachomatis has been developed. Female mice were successfully infected after intravaginal inoculation with the C. trachomatis agent of mouse pneumonitis.

Experimental chlamydial salpingitis in immunosuppressed guinea pigs infected in the genital tract with the agent of guinea pig inclusion conjunctivitis.

At necropsy indication of spread of infection to fallopian tubes was found in 25 of 41 (60%) female guinea pigs infected in the genital tract with the chlamydial agent of guinea pig inclusion conjunctivitis and immunosuppressed with cyclophosphamide. Eighteen were examined histologically, and the diagnosis of acute salpingitis was confirmed in 10, based on inflammatory reaction, detection of guinea pig inclusion conjunctivitis in tissue, and formation of cysts (pyosalpinx and hydrosalpinx). Infection of fallopian tube tissue was confirmed by indirect immunofluorescence and electron microscopy.

Target tissues associated with genital infection of female guinea pigs by the chlamydial agent of guinea pig inclusion conjunctivitis.

Female guinea pigs were experimentally infected in the genital tract with the strain of Chlamydia psittaci that causes guinea pig inclusion conjunctivitis. Chlamydiae were found frequently in superficial squamous epithelial cells of the exocervix, along with heavy involvement at the squamocolumnar junction. In this zone chlamydiae were observed in columnar cells, but inflammation and chlamydial inclusions were not observed in true endocervical epithelium.

Biochemical and morphological characterization of mycobacteriophage R1.

Large-scale propagation of mycobacteriophage R1 in broth culture has allowed the isolation of quantities of virus sufficient for characterization of its nucleic acid and lipid components as well as investigation of its ultrastructural attributes. Analysis of R1 DNA indicates that it is double stranded and possesses a molecular weight of 2.5 X 10(7) and a guanine-plus-cytosine content of 65.