Search PubMed⌕ Search

Biomedical subjects

L Berthiaume

Publications and source records attributed to L Berthiaume.

At least 55 records · Page 3Linked to original sources
PubMed1978

The experimental infection of piglets with a porcine reovirus.

A strain (Quebec) of reovirus isolated from the faeces of a pig with dysentery was neutralised by reovirus type 1 antiserum. Four of eight hysterectomy-produced, colostrum-deprived (HPCD) piglets dosed orally with the third cell culture passage of the virus developed diarrhoea and showed focal areas of villous atrophy in the small intestine. The virus was isolated from the intestinal tract of all eight specific pathogen free piglets, but not from three control animals. Nine germ-free piglets dosed orally with the eight cell culture passage of the virus showed neither clinical signs nor lesions, but virus was recovered from their intestinal tracts for 14 days after infection. No virus was isolated from four control germ-free piglets.

Animals↗
PubMed1977

[Formation of spheriods by cultured human diploid cells].

When human lung diploid fibroblasts are grown in micro-wells in presence of the organic buffer HEPES in an atmosphere of 5% of CO2, the cells migrate and form spheroids. Histologic examination reveals the presence of fibroblastic and epithelioid cells in these spheroids. Signs of degeneration are seen in both cell types under the electron microscope. Following dissociation of the spheroids and their subculture in absence of HEPES, the cells reverse to their original fibroblast-like morphology and grow in monolayer.

Cell Aggregation↗
PubMed1976

Herpes encephalitis. Rapid diagnosis and treatment with antiviral drugs.

The use of specific IgM antibodies and direct electron-microscopic examination of brain biopsies or vesicle fluid was tested as means of raped diagnosis in 6 cases of herpes simplex encephalitis seen consecutively in Montreal. In 2 of 3 biopsies herpes viruses were seen by negative staining of a cell extract within 1 hr. In the negative case, the biopsy was done almost 1 month after onset. In 2 additional cases herpes virus particles were found directly in the fluid of isolated vesicles. In the last 2 cases, who survived, the diagnosis of herpes encephalitis rested upon the demonstration of a greater than 4-fold rise in complement fixing herpes simplex virus antibodies in convalescent sera and upon the appearance late in the course of the encephalitis of specific antibodies in the cerebrospinal fluid. The early appearance of specific IgM antibodies contributed to the diagnosis in 4 of the 6 cases. Antiviral therapy was attempted in alternate cases (3 cases) but was not successful. Brain biopsy is rarely performed for diagnostic purposes but when prompt antiviral therapy is contemplated, the examination of the biopsy material for herpes virus particles by electron microscopy in negative staining and thin sections can rapidly and reliably confirm the diagnosis.

Aged↗
PubMed1976

Structural aberrations in group A Staphylococcus bacteriophages.

Six related Staphylococcus phages spontaneously produced various abnormal head and tail structures: (i) giant capsids which were tailed and apparently contained nucleic acid; (ii) regular and irregular smooth polyheads; (iii) heads and polyheads with wavy outlines; (iv) mottled heads and polyheads; (v) abnormally long and short tails; and (vi) "double capsids" connected by a small bridge. Some of these structures are rare, or have not yet been reported. The frequency os specific aberrant particles varied from one phage to another. Length distribution of smooth irregular polyheads and of abnormal tails indicated that these structures assemble at random from protein synthesized in excess. These phages represent an interesting model for genetic and morphogentic studies.

Capsid↗
PubMed1971

Rapid diagnosis by electron microscopy of avian coronavirus infection.

The election microscopic examination of allantoic fluid from embryonated hens' eggs inoculated with tissue homogenates from organs of birds suffering with infectious bronchitis, reveals the presence of coronaviruses as early as the first or the second passage. This method permits a rapid diagnosis and is as accurate as the standard technique.

Animals↗