Search PubMed⌕ Search

Biomedical subjects

M T Green

Publications and source records attributed to M T Green.

34 records · Page 2Linked to original sources
PubMed1984

Detection of herpes simplex virus induced polypeptides in rabbit trigeminal ganglia.

The objective of this study was to follow herpes simplex virus type 1 (HSV-1) genome expression in rabbit trigeminal ganglia during primary, latent, and artificially reactivated infections using monospecific antiserum to representatives of the sequentially produced alpha, beta, and gamma group polypeptides. Rabbits with or without electrode implants were inoculated with 10(5) plaque forming units of McKrae strain HSV-1 following scarification and monitored by daily preocular tear film culture. Animals were killed during primary, latent, and artificially reactivated infections. Representative trigeminal ganglion sections from each animal were reacted with either preimmune rabbit serum, anti-HSV-1, anti-ICP-4, anti-ICP-8, or anti-ICP-5 sera. During primary infection, staining was evident in 30-40% of the ganglion cell nuclei with all antisera. During latency, staining with anti-ICP-4 was detected in 14 out of 18 ganglia tested; 10-15% of the ganglion cell nuclei per section exhibited positive staining. A +/- staining pattern with anti-ICP-8 was obtained in 5 out of 14 of the ganglia tested; 1-3% of the nuclei per section exhibited this staining pattern. Staining with anti-HSV-1 and anti-ICP-5 was not detected. During induced reactivation, staining of ganglion cell nuclei with all antisera was observed, but the number of cells staining per section was decreased compared to that observed during primary disease.

Animals↗
PubMed1981

Endogenous Candida albicans endophthalmitis in the rabbit. Chemotherapy for systemic effect.

Progressive endogenous Candida albicans endophthalmitis was established in rabbits by intravenous (IV) injection of blastospores (2.0 to 5.0 x 10/kg). Severity of infection was directly related to the strain and inoculum size. Intravenous amphotericin B (1.0 mg/kg/day), IV amphotericin B methyl ester ascorbate (5.0 mg/kg/day), and oral ketoconazole (80 mg/kg/day) effectively prevented or reduced the severity of infection when therapy was initiated 24 hours following inoculation of blastospores and continued for five to seven days. Intravenous miconazole (30 mg/kg/day) was ineffective in this model. Intravenous amphotericin B(1.0 to 2.0 mg/kg on alternate days), IV amphotericin B methyl ester ascorbate (5.0 mg/kg/day), and oral ketoconazole (80 mg/kg/day reduced the severity of C albicans endophthalmitis when therapy was initiated seven days following injection of blastospores and continued for 28 days. Oral flucytosine (75 and 150 mg/kg/day in four doses) produced uniformly fatal hepatic necrosis in uninfected rabbits.

Amphotericin B↗
PubMed1981

Quantitation of herpes simplex virus type 1 shed in preocular tear film of rabbits treated with acyclovir.

The quantity and duration of herpes simplex virus type 1 shedding in the preocular tear film of rabbits were measured before, during, and after administration of acyclovir topically, intravenously, and by these routes. Topical administration reduced shedding significantly, Intravenous administration was without effect and in the combination regimen added nothing to the effectiveness of local application. The effects of acyclovir were temporary because there were significant increase in preocular tear film virus shedding after cessation of treatment.

Acyclovir↗
PubMed1981

In vivo reactivation of herpes simplex virus in rabbit trigeminal ganglia: electrode model.

The rabbit provides an excellent model for the study of ocular herpes because herpetic keratitis in the rabbit eye resembles human disease in its clinical features and in its propensity for spontaneous recurrence. This paper presents a method for the electrical induction of multiple episodes of in vivo reactivation of latent HSV-1 infection with peripheral shedding of virus. Physiological levels of current delivered via an electrode implanted over the trigeminal ganglion of latently infected animals has enabled us to modify and synchronize virus shedding in preocular tear film and to cause multiple episodes of reactivation in a single animal. For this reason, the model is well suited for antiviral efficacy testing and provides an excellent opportunity for investigation of virus-host cell interactions in latent and recurring herpetic disease.

Animals↗
PubMed1981

Detection of an immediate early herpes simplex virus type 1 polypeptide in trigeminal ganglia from latently infected animals.

In this study, trigeminal sensory ganglia from animals with acute herpes simplex virus, type 1 (HSV-1) infection were compared to those with a latent infection for the expression of HSV-specific antigens. By the indirect immunofluorescence assay, antisera to an immediate early polypeptide of molecular weight 175,000, designated VP175 or ICP4, and a hyperimmune antiserum to HSV-1 were used to determine whether early viral polypeptides were being expressed in neurons during the latent stage of infection. All 17 ganglia from animals with acute infection (sacrificed 3 to 12 days postinfection) exhibited positive staining when treated either with anti-HSV-1 or with anti-VP175. Forty of 42 ganglia from animals sacrificed during the latent stage of infection (22 to 200 days postinfection) exhibited immunofluorescent staining when treated with anti-VP175. The staining appeared to be similar to that observed in ganglia from acutely infected animals stained with anti-VP175, except that the number and distribution of stained cells were markedly reduced. No immunofluorescence was observed in ganglia from noninfected control animals when stained with anti-VP175 or anti-HSV-1, or when ganglia from latently infected animals were stained with anti-HSV-1 or preimmune serum.

Animals↗
PubMed1981

Quantitation of herpes simplex virus in vitro and in preocular tear film.

Current methods for virus isolation from preocular tear film are not quantitative. This report presents a sensitive method for detection and quantitation of herpes simplex virus type 1 in unknown samples of small size (less than 50 microliters). Serial tenfold dilutions of stock virus were inoculated onto 16 mm vero cell monolayers, which were monitored for the development of cytopathologic evidence (CPE) for presence of virus and were assigned a severity grade. Standard curves were developed on the basis of time interval between inoculation, recognition of CPE, and CPE score. These curves were used to predict virus titers in unknown samples. This method for virus isolation is simple, efficient, and consistently sensitive to virus titers of less than 10 plaque forming units.

Animals↗
PubMed1979

Effects of an enkephalin analog on complex learning in the rhesus monkey.

Facilitation of the learning of a discrimination reversal task for a reward of food was found in rhesus monkeys after subcutaneous administration of a potent pentafluorinated enkephalin analog. (D-Ala2)-F5-Phe4-enkephalin-NH2. General activity, short-term memory, startle, and analgesia, however, were not significantly affected. In a within-subject design, each of 6 monkeys (3 males and 3 females) received each of 5 doses of the enkephalin analog (0.1, 1, 10, 100, and 1,000 microgram/kg). One daily injection was made for 7 consecutive days, including pre- and posttests on the first and last days with the diluent control. The enkephalin doses, with the exception of the 0.1 microgram/kg level, produced significantly faster learning than the diluent. Some sex differences were suggested by the data, but these effects are difficult to interpret. The results suggest that relatively small amounts of this analog given systematically can exert a reliable effect on a complex behavior such as reversal learning at doses devoid of opiate effects, due perhaps to enhanced cognitive flexibility rather than improvement in short-term memory or association formation.

Analgesia↗
PubMed1977

Reliable in vivo model for latent herpes simplex virus reactivation with peripheral virus shedding.

A long-sought laboratory model, a reliable system for in vivo reactivization of latent herpes simplex infection with peripheral shedding of active virus, is present. Results demonstrate that surgical stimulation of latently infected rabbit trigeminal ganglia induces peripheral release of infectious herpes simplex virus. Virus could be cultured from the tear film in 83% of the stimulated animals' eyes within 48 h.

Animals↗
PubMed1974

Demonstration of the phenomena of microbial persistence and reversion with bacterial L-forms in human embryonic kidney cells.

A series of experiments was undertaken in which human embryonic kidney (HEK) fibroblasts were infected with either relatively stable or stable L-forms of Streptococcus faecalis. The infected cells were maintained by splitting over long periods (1 to 2 months) while samples were withdrawn for culture and electron microscopic studies. Relatively stable S. faecalis L-forms could be cultured from infected cells only during the first week after infection, although L-form-like material was frequently detected at later periods by electron microscopy. HEK cells continued to proliferate and showed no gross histopathology until reversion occurred. At reversion, electron microscopy revealed the presence of intracellular L-forms, transitional variants, and intra- and extracellular bacterial forms. Unlike relatively stable L-forms, stable L-forms were culturable throughout the experimental period. These experiments demonstrate the phenomena of persistence and reversion in vitro. Electron microscopy indicated that the L-forms entered the HEK cells, where they underwent morphological changes. Observations suggested that these altered L-forms (elementary bodies) persisted in the cell until reversion to the parent bacterial form was triggered. Infected cells, when treated with L-form antiserum and stained with fluorescein-conjugated goat anti-rabbit serum, were consistently positive regardless of cultural findings.

Antigens, Bacterial↗
PubMed1974

Proposed reproductive cycle for a relatively stable L-phase variant of Streptococcus faecalis.

Based on electron microscopic observations, the reproductive cycle of a relatively stable L-phase variant of Streptococcus faecalis was proposed. The small, dense, nonvesiculated L-form is envisioned as the central (core) element. It was seen to divide and bud rapidly. In addition, the dense forms appeared to be capable of growth and development within vesicles of mature mother forms. When these forms were released from the vesicles into the surrounding fluid medium, further growth occurred, resulting in the development of immature and ultimately mature mother forms. Under conditions unfavorable for L-form growth, these dense forms developed first into transitional forms and then into the bacterial form. These dense forms might therefore be considered as undifferentiated "stem cells' with the capacity to develop along several different routes, depending upon the stimulus received.

Cell Differentiation↗
PubMedDate not supplied

Possible role of HHV-6 in the development of AIDS retinitis.

Majority of AIDS patients experience visual loss due to AIDS-associated retinitis or commonly known as CMV retinitis. It has been reported that CMV infection of the retina is a late manifestation of AIDS and a poor prognostic sign. The etiology and mechanism(s) involved in the development of AIDS-associated retinitis is currently unknown. It is of critical importance to understand the pathobiology of this disease process in order to develop a rational approach to therapeutic intervention. We have determined the frequency and proximity of simultaneous occurrence of HIV-1 and HHV-6 in retinal tissues of AIDS patients in the absence of CMV infection. Active infection of HIV-1 has been identified in the retinal tissues of 30-60% of AIDS patients analyzed. HHV-6 antigens and transcripts were detectable in about 50% of HIV-1 positive retinas. Most significant finding of our studies is the presence of HIV-1 and HHV-6 antigens and transcriptional activity in retinal tissue in the absence of CMV infection. These observations suggest that HIV-1 in association with HHV-6 may predispose certain retinal cells to other opportunistic agents such as CMV in late stages of AIDS-associated retinitis.

AIDS-Related Opportunistic Infections↗