In this thesis, an attempt was made to demonstrate the possible role of monocytes in producing antibody in vitro. Series of experiments were carried out in vitro, under this line, to confirm previous results obtained in vivo by Girard & Murray (67). These authors observed in rabbits maintained in a state of monocytosis that these animals will give a significantly elevated titer over that of control animals when they are immunized against S. typhosa, staphylococcus toxoid and Horse serum. [...]

Isolation of Mycobacterium tuberculosis from cerebro spinal fluid has been always considered the cardinal point for the diagnosis of tuberculous meningitis, although in some instances is difficult or impossible and the diagnosis has to rely on the cytological and chemical changes of the fluid and on the patient's symptoms. To better understand the value of the bacteriological findings and or the pathological changes of cerebro spinal fluid in tuberculous meningitis, it seems advisable to us to review briefly the disease and its new aspects since the advent of therapy.

Ever since Koch, in 1882, announced the discovery of the aetiological agent of tuberculosis, which he named the tubercle bacillus, scientists throughout the world have been trying to improve existing methods of the culture or this organism that has been the scourge of mankind for centuries. One of the attempts to achieve rapid and accurate bacteriologic diagnosis has led to the recent development of the slide-culture technique for growing tubercle bacilli.

The true pathogenic yeasts are organisms of much clinical importance. One species, compensating for its relatively rare occurrence by its extreme virulence, produces systemic diseases which are almost always fatal, while most representatives of the group are significant chiefly for their very wide distribution, and frequent isolation as the causative agents of lesions of the skin, nails, and mucous membranes in man and animals. They are imperfect fungi, lacking any sexual conjugation or spores, and they reproduce by simple budding or the formation of asexual conidia.

Penicillium cyaneo-fulvum, which was found growing as a contaminant on a Lowenstein slope in the Clinical Laboratories of the Department of Bacteriology, McGill University, by Denton (1947), has been shown to produce at least three distinct substances. The mould produces an antibiotic, probably penicillin, a toxin neutralizing substance, noxiversin (Diena, 1954, 1956; Murray, Denton, Stevenson and Diena, 1958) and an antiviral factor (Diena, 1956; Cooke, 1958, 1960). Noxiversin, studied in some detail by Diena and others (Ajemian, 1957; Diena, 1954, 1956; Murray et al., 1958; Tanner, 1956, 1957), was found to possess, in addition to its antitoxic properties, some activity against influenza virus (Diena, 1956).

Scopulariopsis brevicaulis (Saccardo) Bainier is a member of the Fungi Imperfecti. It is a mould which, like many species of Fungi Imperfecti, is widely distributed throughout the world. Of the many species in the genus Scopulariopsis, this organism has attracted the most attention. A review of the literature shows that it is important not only as a saprophyte but also as a parasite. As a human parasite it is most commonly encountered as a dermatophyte. Reviews by Dodge (1935), Raper and Thom (1949), Conant et al. (1954) and more recent reports such as Fischer's review of clinical cases (1960) and a report from Poland by Kapica (1960) indicate that S. brevicaulis is isolated from clinical material more frequently than any other recognized species belonging to this genus.

Note: Missing Page 57. / Interest on the part of the author in this problem was stimulated by the lack of information about the organism L. monocytogenes, its epidemiology and its ability to grow under certain conditions. There has been great controversy in the past few years, as more data about human Listeriosis became available, about the significance of L. monocytogenes in foetal death and in neonatal disease. There have been reports in the literature, naming L. monocytogenes as a cause of a large percentage of repeated abortions in women in certain areas. Other authors have felt that the importance of L. monocytogenes has been over-estimated.

In recent years, the study of antibody synthesis in vitro has aroused considerable interest. Not only does it enable the immunologists to study the phenomenon of antibody formation at a cellular level, free from various factors often associated in a whole body, but also it serves as a model for biochemists in the study of biosynthesis of a specific protein. An antigen is a complex molecule, and very often it contains more than one determinant group that can elicit antibody response. The antibody thus demonstrated in an in vitro system against a microbial antigen cannot necessarily be equated with a measure of immunity against the infection.

Previous work in this department by the present author and others, has demonstrated that changes accompanying the acquisition of resistance to chloramphenicol in Salmonella indicate structural changes in the surface of resistant organisms. Similar changes have been reported by other workers investigating both gram-positive and gram-negative chloramphenicol resistant organisms. The additional observation of a simultaneous increase in resistance to other antibiotics such as penicillin implies a possible non-specific mechanism contributing to resistance linked to the relative permeabilities of the cells. Work was therefore continued with a resistant strain of Salmonella typhimurium in an attempt to find out more about the mechanism of resistance.

Ribonucleic acid (RNA) of tobacco mosaic virus controls the specificity of viral proteins synthesized in the cells of tobacco leaves (Fraenkel-Conrat et al, 1957a) and in a bacterial cell-free system (Taugita et al, 1962). In bacteria, three types of RNA are now recognized, transfer (Berg and Ofengand, 1958), ribosomal (Schachman et al, 1952), and a so-called "messenger” or “rapidly labelled" RNA (Volkin and Astrachan, 1956). The “messenger” fraction is thought to control the specificity of proteins synthesized in bacterial cells (Nomura et al, 1960; Brenner et al, 1961; Gros et al, 1961a; Jacob and Monod, 1961), although direct proof for this claim has not yet been obtained.