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Primers specific to conserved and variable regions in the 16S rRNA sequence were selected from the partially sequenced 16S rRNA genes of Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, S. agalactiae, and Staphylococcus epidermidis. The PCR assay was divided into two DNA amplifications. The first resulted in a general bacterial amplicon, and the second resulted in a species-specific amplicon. The high specificity of the PCR assay was documented after testing bacteria of 28 different species (133 strains). A total of 304 clinical cerebrospinal fluid samples, including 125 samples from patients with bacterial meningitis, were assayed to investigate the diagnostic sensitivity and specificity for bacterial meningitis. The assay showed high sensitivity (0.94) and specificity (0.96) with the clinical samples, although some false results were obtained, the reasons for which are discussed. With agarose gel electrophoresis for detection of the PCR products, the detection limit for meningococci in cerebrospinal fluid was 3 x 10(2) CFU/ml.

An alpha-2 proteobacterium, previously unknown as determined by its phylogenetic characteristics and the DNA sequence of its 16S rRNA gene, was isolated from a patient who presented an unusual clinical picture, including high remitting fever and multiorgan involvement. The bacterium was detected in multiple plasma samples, obtained during the acute phase of the disease, after cocultivation in cell culture media. Electron microscopy of the organism showed a three-layer laminar cell wall and electron-dense granules within the cytoplasm, as well as a polar flagellum. By means of PCR followed by sequencing of amplified 16S ribosomal DNA fragments, the bacterium was found to differ from all species for which ribosomal sequence information is available. It is here provisionally named the Rasbo bacterium. At a subsequent relapse, the bacterium was identified in pericardial fluid both by PCR/sequencing and by direct electron microscopy. At a second relapse, it was again cultured from plasma. After in vitro adaptation to solid media, the MICs of various antibiotics could be determined. A transient immunoglobulin M (IgM) but no IgG response to the bacterium was found by an indirect immunofluorescence test, as well as by an immobilization test during the acute phase of the disease.

The aberrant stickleback in the Karlskrona archipelago is probably a completely new form within the three-spined stickleback Gasterosteus aculeatus complex. Males of this type differ from sympatric, normal stickleback males by being smaller and by having less striking nuptial coloration. They also build nests in algae above the bottom, whereas normal stickleback males build their nest at the bottom. Moreover, observations suggest that aberrant stickleback males have emancipated from most of the care of nest and offspring as they appear to transport fertilized eggs from the nest to the surroundings where they are left unattended. Whether this can be explained by sex-specific reproductive strategies or by any other means is investigated. Preliminary results suggest the aberrant stickleback to be genetically distinct from regular morphs. The project will investigate this further and hopefully clarify whether the aberrant type has evolved in the Karlskrona archipelago, thus probably in sympatry with normal sticklebacks, or if it is of allopatric origin. With reproductively important morphological and behavioural deviations, our first guess would be that isolation is mediated through sexual selection. If this is true, isolation may have been relatively rapid making a sympatric origin less unlikely. The aberrant form is very rare and endangered. Presently, it is only found at two sites, both of which are threatened by an impending ferry terminal construction. A major aim of the project is to help preserve the aberrant stickleback. Most importantly, aberrants will be collected for captive breeding and introduction to new localities.

A litCon mutation in Escherichia coli TU6 results in exclusion of bacteriophage T4 during the late, morphogenetic stage of its development at low temperatures. DNA was synthesized continuously in the infected cells, but less than 10% of the DNA made by 90 min after infection was packaged into DNAase-resistant particles, few viable phage were formed, and the cells lysed poorly. The exclusion could be relieved by conditions leading to elevated levels, determined immunologically, of the E. coli Rho protein (believed to be involved in regulation of T4 transcription), or chromosomally encoded E. coli GroEL (a chaperone known to be involved in phage assembly), or by supplying GroEL in trans from a plasmid. The two suppressing proteins appeared to act independently of each other. GroEL-suppression restored packaging to normal levels, perhaps by preventing GP23 from activating the host Lit protein; in addition DNA synthesis was delayed and reduced and cell lysis enhanced, demonstrating involvement of GroEL in both these processes. Rho suppression was less efficient. Since both transcription-termination-proficient and transcription-termination-deficient Rho suppressed, the results raise the possibility that Rho has a role during T4 development not directly involving transcription regulation.

60 women with bacterial vaginosis were entered into a double blind, placebo-controlled treatment trial with lyophilized Lactobacillus acidophilus. The lactobacilli used were producing H2O2. Immediately after completion of treatment, 16 out of 28 women who were treated with lactobacilli had normal vaginal wet smear results, in comparison to none of the 29 women treated with placebo. All women harboured Bacteroides at inclusion. Bacteroides was eliminated from the vagina of 12 out of 16 healthy women after treatment. Only three of the women who received the Lactobacillus suppository were free of bacterial vaginosis after the subsequent menstruation.

Morphologically different Lactobacilli can be observed in wet smear preparations from the lower female genital tract; this morphological difference seems to correlate with the ability of the bacterium to produce hydrogen peroxide. This discussion will examine the role of the normal bacterial flora in protection of the host against recurrent infections. Further, we will propose a model as to how the potential role of immunological tolerance or 'immunological preference for' the maternal bacterial flora, can give individual differences in disposition for infections.

Numerous studies have shown that the presence of Helicobacter pylori in the stomach is linked to the development of chronic gastritis most commonly seen in the antrum. However, the pathogenic mechanisms are unclear. In 23 of 31 patients, examined due to symptoms from the upper gastrointestinal tract, H. pylori-associated chronic gastritis of the antrum was diagnosed histologically and by growth of H. pylori. Immunoperoxidase staining on gastric biopsy specimens from these patients showed an increased number of gamma/delta T-cells within the epithelium. Furthermore, the Mab ML30 (raised against the 65 kDa heat shock protein of mycobacteria) demonstrated positive staining in the gastric epithelial cells in all H. pylori-positive but not in H. pylori-negative biopsy specimens. H. pylori also reacted with ML30, as detected by immunoperoxidase staining as well as by immunoblotting. Intraepithelial gamma/delta T cells may play a role in host defense against invading H. pylori, and the bacteria may trigger an autoimmune response to stress proteins expressed by the gastric epithelial cells.

Seventy women scheduled for abdominal hysterectomy were examined for the presence of clue cells in the vaginal discharge in an attempt to identify a possible risk group for development of postoperative infection. Seven of 20 women (35%) with clue cells developed vaginal cuff infections or wound infections, compared with four of 50 women (8%) without clue cells (P less than .01). Women with bacterial vaginosis, diagnosed by air-dried vaginal smears, are therefore at risk for postoperative infection.

The occurrence of motile anaerobic curved rods in vaginal discharge was studied in 94 samples from women attending an STD clinic. Almost all wet smear preparations of discharge contained motile rods. Anaerobic curved rods were isolated from 46% of the samples. Of 28 specimens studied by culture and immunofluorescence, 21 were confirmed to harbour motile anaerobic curved rods. Culture was performed with a dilution and sampling technique that is too time-consuming for diagnostic routines, but it enhanced the precision of information on motile anaerobic curved rods in vaginal secretion. More selective and rapid methods for identification of these bacteria are desirable.

Numerical analysis of phenotypic data on 38 strains of anaerobic curved rods (CR) and 7 reference strains indicated that the curved rods could be split into two types, anaerobic long (LCR) and short curved rods (SCR). In addition, a subcluster was formed within the cluster of SCR by strains that are both morphologically and biochemically intermediate between the LCR and SCR group. None of the reference strains could be grouped into the clusters of CR. DNA-base composition was 52-54 mol% GC for LCR and 56-58 mol% GC for SCR. Serologically the two groups are distinct.

For many years gram-negative bacteria have been found to be attached to human gastric mucosa. S-shaped bacteria were seen closely associated with the surface epithelium, both within and between the gastric pits. The successful culture of these organisms from gastric biopsy material was reported in 1983 by Marshall and Warren [1]. Due to similarities to Campylobacter strains and frequent occurrence in the distal stomach the bacteria were termed Campylobacter pyloridis [2]. However, in 1987 the bacteria were renamed as Campylobacter pylori [3]. The organisms are found almost exclusively in connection with inflammatory changes of the gastric mucosa, and a proposed causal relation between C. pylori, gastritis and ulcer disease is under intense investigation throughout the world. This paper describes monoclonal antibodies for the detection of these bacteria, compared to culture and to another proposed method for rapid detection, namely direct inoculation of urea broth [4].