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An apparent increase in the incidence of S. Brandenburg in New Zealand, coupled with the possibility that the virulence of the organism may also be changing, prompted this study.Three typing methods: macro-restriction fragment length polymorphism (MRFLP) profiling using pulsed field gel electrophoresis (PFGE), plasmid profiling and antimicrobial susceptibility profiling were used to determine strain diversity amongst 115 recent and historical isolates of S. Brandenburg from both human cases and non-human sources.Antimicrobial resistance was noted only in three isolates. Plasmids of varying sizes were found in 31 isolates. MRFLP analysis resulted in 13 different patterns. Combining the three sets of typing data yielded 24 composite types. Comparison of composite type, isolation date and geographical location of case allowed the retrospective recognition of seven potential clusters during the 5-year study period. Composite types of 24 (80%) of the non-human isolates tested were indistinguishable from human isolates, suggesting that human infection may be via a number of vehicles.Although not cost-effective for routine use on all salmonella isolates, the methods used in this study are an important adjunct to serotyping for discrimination within an emerging serotype.

AIMS--To compare the predictive value of immunoblotting and enzyme linked immunosorbent assay (ELISA) in diagnosing Lyme borreliosis. METHODS--An ELISA using a whole cell sonicate of the B31 strain of Borrelia burgdorferi was used to screen samples submitted for Lyme borreliosis serology. A total of 1222 serum samples reactive in the ELISA were tested by immunoblotting also using the B31 strain. Patients with other spirochaetal diseases were tested by both methods to assess specificity, while those with erythema migrans were used to evaluate sensitivity. Subjects with different clinical conditions, which may have been associated with Lyme borreliosis, were tested using both techniques. RESULTS--Only 16.3% of serum samples from patients submitted for Lyme borreliosis serology which were reactive by ELISA were confirmed as positive by immunoblotting. This is unlikely to represent a sensitivity problem as 51% of samples from 53 patients with erythema migrans were detected by immunoblotting compared with only 28% by ELISA. Patients whose samples were negative by ELISA were also negative by immunoblotting. Serum samples from patients with relapsing fever were reactive in both ELISA and by immunoblotting, but for other test groups immunoblotting offered increased specificity. CONCLUSIONS--Not all ELISA results could be confirmed by immunoblotting. Yet immunoblotting was both more sensitive and specific than ELISA techniques. As a result of these observations all ELISA results should be serologically confirmed by immunoblotting. Though immunoblotting is not suited to large scale screening of samples, it can be used satisfactorily in conjunction with ELISA methods to improve the predictive value of serological tests for Lyme borreliosis.

Three species of redfish (Sebastes) share a common pattern of mitochondrial DNA tandem repeat polymorphism and heteroplasmy in the northwest Atlantic Ocean. All three species exhibit 9-17 copies of an approximately 275 base pair (bp) tandem repeat situated within the 3' domain of the control region. Sequence analysis of cloned mtDNA from S. mentella revealed that the tandem array is adjacent to the tRNA(phe) gene, and that the repeat shares 53% identity with the tRNA(phe) gene and part of the 12S rRNA gene. These features, as well as potential secondary structure assumed by the repeat, are consistent with previously proposed models explaining tandem duplications in the 3' end of the control region. In a sample comprising 36 S. fasciatus, 52 S. mentella, and 13 S. marinus taken near Newfoundland, neither the mean number of repeats per fish (12.2-12.7) nor the frequency of heteroplasmy varied significantly among species. A total of 42% of the redfishes were heteroplasmic, bearing either two or three repeat variants (33% and 9%, respectively). The similarity of the frequency distributions of tandem repeat variants in the three species suggests either a common balance between mutation and selection in the three species, or mitochondrial gene flow between them.

Objective- Serology has traditionally been the mainstay of diagnosis in Lyme disease (LD). This approach has limitations because of the delayed humoral response to infection, the presence of cross-reactive antibodies arising from commensal and pathogenic spirochaetes and the heterogeneity of the species of Borrelia causing Lyme disease. The polymerase chain reaction (PCR) is a highly sensitive and specific technique which offers an alternative approach to laboratory diagnosis.

We have amplified, by the polymerase chain reaction, and have sequenced the D-loop region of the mitochondrial DNA from the sperm whale (Physeter macrocephalus). The sperm whale D-loop was aligned with D-loop sequences from four other cetaceans (Commerson's dolphin, orca, fin whale, and minke whale) and an out-group (cow). This alignment showed the sperm whale sequence to be larger than that of other cetaceans. In addition, some sequence blocks were highly conserved among all six species, suggesting roles in the functioning of mitochondrial DNA. Other blocks that were previously reported to be well conserved among cetaceans showed little sequence conservation with the sperm whale D-loop, which argues against the functional importance of these sequence blocks in cetaceans.

1. The effect of isoniazid given daily for 7 days on paracetamol (acetaminophen) kinetics and metabolism was studied in 10 healthy volunteers. Paracetamol, 500 mg, was given before isoniazid, on day 7 of isoniazid administration, and 2 days after the last dose of isoniazid. 2. On day 7, isoniazid markedly inhibited the formation clearance of the glutathione and catechol metabolites by 69.7% and 62.2%, respectively. Total paracetamol clearance was lowered by 15.2%. There was no effect of isoniazid on the non-oxidative pathways of paracetamol elimination. 3. Two days after isoniazid was discontinued, paracetamol metabolism had returned to pre-isoniazid values.

A total of 670 Citrullus species accessions were evaluated for resistance to watermelon mosaic virus 2. In greenhouse tests seedlings to be evaluated were mechanically inoculated, and in field tests plants in spreader rows were mechanically inoculated. Plants were considered virus free by the absence of disease symptoms and by negative results in enzyme-linked immunosorbent assay. Our working definition of resistance was the ability of a plant to withstand, oppose, lessen, or overcome the attack of a pathogen. Plants were considered resistant if virus free 10-14 days after final inoculation in the greenhouse, or virus free 4-6 wk after inoculation of the spreader-row plants in the field, even though many were subsequently infected (.)

The in-vitro activity of the new parenteral cephalosporins, HR 810 (HR) and BMY-28142 (BMY), was compared with that of other beta-lactam antibiotics, including cefotaxime, against a total of 315 recent clinical isolates and characterized beta-lactamase producers. An agar dilution procedure was used to determine MICs and two inocula (10(4) and 10(6) cfu) were used throughout. Against all species of the Enterobacteriaceae tested, both HR and BMY were as active as, or slightly more active than, cefotaxime. HR differed from cefotaxime mainly in being eight-fold more active against Pseudomonas aeruginosa and two-fold more active against Staphylococcus aureus. BMY was also eight-fold more active than cefotaxime against Ps. aeruginosa but was two-fold less active than the latter against Staph. aureus. Both new compounds had good activity against Haemophilus influenzae, including the beta-lactamase producing strains of that species, and both had poor activity against the Bacteroides fragilis group (MIC90 greater than 128 mg/l).

The terminal changes following Borrelia duttoni infection in mice consisted of disseminated intravascular coagulation with associated depression in temperature, and in white cell and platelet counts with the development of a positive limulus lysate test. Apart from thrombosis and haemorrhage, similar changes were found in mice given cyclophosphamide prior to infection. The results suggest that neither intravascular coagulation nor immune complex formation are major factors in causing death in borreliosis.

The site of neuromuscular blockade induced by clindamycin and lincomycin was studied on isolated nerve and nerve–muscle preparations. Clindamycin (3.6 × 10−3 M) but not lincomycin (up to 1.5 × 10−2 M) had a local anaesthetic effect on a frog desheathed nerve preparation. Clindamycin (8 × 10−4 M) and lincomycin (4 × 10−3 M) depressed the response of the rat diaphragm to nerve stimulation and to direct muscle stimulation in parallel. This indicated that the predominant neuromuscular blocking effect of these antibiotics was due to an effect on the muscle. Clindamycin was fivefold more potent than lincomycin in this effect, and the unionized form of both drugs was the active form. Lincomycin (4 × 10−3 M) but not clindamycin (8 × 10−4 M) also had some depressant effect on nerve–muscle transmission as indicated by the interaction of the effects of the antibiotics and d-tubocurarine. The significance of these findings is discussed in relation to the acute clinical toxicity of these antibiotics.

At high population densities, the amphibious and herbivorous mudskipperBoleophthalmus boddarti construct mud walls around their territories as a means of reducing aggression between neighbours. Because of the walls, territories contain pools of water and exposed mud slopes. Whilst the density of benthic diatom prey was highly variable, the highest was found on the exposed mud slopes and the lowest on the boundary walls. Fish grazed mainly on the mud slopes. There were no significant differences in diatom density between territorial and non-territorial areas or between grazed and non-grazed areas within territories. The variation of the diatom density, however, was reduced within territories. The mud walls are considered to play a secondary, indirect role in maintaining populations of diatoms within territories.

We examined the effects of simian virus 40 infection on the temporal and spatial organization of initiation sites for DNA replication in Muntjac cells by means of light microscopic DNA fiber autoradiography. Initiation at multiple sites along the DNA fiber in virus-infected confluent Muntjac cells was more nearly synchronous than in serum-deprived controls, although temporal control in the infected cells did not reach the level observed in cells incubated in serum-enriched medium. Initiation sites in virus-infected cells appeared to be spatially closer together than in either uninfected serum-deprived or uninfected serum-enriched cells. This change did not appear to be the result of the induction or repression by simian virus 40 of clusters of replication units with new and different organizations.

A seroepidemiological survey was undertaken in Addis Ababa to assess the prevalence of chlamydial genital infections among patients attending a sexually transmitted diseases (STD) clinic and patients with no overt genital symptoms. In the STD clinic patients antibodies to Chlamydia trachomatis serotypes D to K (genital types) were detected in 68 of 210 (32.4%) men and in 72 of 159 (45.3%) women, a rate of exposure as high or higher than that found in Europe. Serological evidence of active chlamydial infection was present in 26.7% of men and 28.9% of women. Women were at risk of contracting STD, including chlamydial infections, at the age of 14 years or earlier. The titres of antichlamydial IgG were extremely high in some patients attending the STD clinic, with titres of between 1/512 and 1/8192 in 9.5% of men and 13.2% of women. This suggests that some patients had severe or disseminated chlamydial disease. The prevalence of exposure to chlamydial genital infections among 148 patients with no overt genital disease was 14.2%, which is significantly higher than that found in the United Kingdom. Among the total of 517 patients tested the prevalence of exposure to trachoma, lymphogranuloma venereum, and Chlamydia psittaci agents was very low.

Summary The in-vitro bactericidal effect of serum for Klebsiella rhinoscleromatis was tested. Experiments with C2-deficient and hypogammaglobulinaemic human sera suggested that killing depended on activation of the classical complement pathway, although the alternative pathway probably amplified the effect. Serum from a patient with active rhinoscleroma, and another cured of the disease, showed normal killing.

A 32P-labeled fragment of DNA containing the speC gene, which encodes the biosynthetic enzyme ornithine decarboxylase of Escherichia coli, was used as a hybridization probe for homologous sequences in the genomes of gram-negative and gram-positive bacteria. The speC probe detected homologous sequences in the DNA of only four members of the Enterobacteriaceae (Citrobacter freundii, Salmonella typhimurium, Klebsiella pneumoniae, and Enterobacter aerogenes); no homology was detected with the DNA of other representative members of the Enterobacteriaceae and gram-negative and gram-positive bacteria.

Summary A hitherto unrecognised lipoprotein liver-cell inclusion is described in elderly mice. The significance of these inclusions is unknown. In an experiment to determine the effect of Treponema pallidum on the lifespan of mice (Wright & Wharton, ] 977) an inclusion which had not previously been described was detected in the liver. 30 were inoculated intra peritoneally with a formalinkilled suspension, JO with only the suspending medium, and 20 uninoculated mice were held over for the period of the experiment. From the infected group JO mice were sacrificed at intervals of 6 months, while 10 mice inoculated with dead spirochaetes were killed at 30, 36 and 42 months following the commencement of the experiment. Organs of all these mice were submitted to microscopical examination.

In laboratory rearing studies on the carrot weevil, Listronotus oregonensis (LeC.), at Urbana, Illinois, during the summers of 1951 and 1952, the average duration of the life cycle from egg to adult in two generations each ranged from 33.5 to 41.1 days. With maximum longevity for adult females of 103 days for the first generation and 428 days for second generation extreme overlapping makes a clear demarcation of the two principal generations difficult.

A water-borne Bacillus licheniformis infection was associated with depressed haemoglobin content, white cell and platelet count. The epidemic was resolved by changing from tanked to mains water supply.

SUMMARY Intraperitoneal infection with Treponema pallidum did not shorten the lives of inbred CBA mice. One hundred and fifty infected mice survived to a mean age of 41-24 months and 60 uninfected mice to a mean age of 41-38 months.

Much is now known about the compositions of modern stromatolite-building communities (see review by Golubic 1976). Such stromatolites, although from widely separated areas, are built by a limited number of micro-organisms. These often possess special adaptations which allow them to survive under the rather special conditions in which they live. Many forms inhabiting intertidal settings for example produce gel envelopes which enables them to resist desiccation, while other forms exhibit motility which helps prevent burial by sediment (Golubic and Campbell 1979).

BONE changes in Neanderthal remains which, it has been suggested1, might be caused by rickets are not unlike those seen in certain treponemal diseases, notably congenital syphilis. Examining the Neanderthal collection at the British Museum (Natural History), I noted several features compatible with treponemal disease.

A test is described to distinguish the immunofluorescence seen on T. pallidum in syphilis from that due to antibodies against DNA. The method consists of comparing the results of the fluorescent treponemal antibody (FTA-ABS) test with the staining obtained with T. gondii and T. cruzi using an indirect fluorescent technique. The ability of a particular serum to stain other organisms, in addition to T. pallidum, at a significant titre indicates that the treponemal fluorescence is not specific, and the loss of this staining property when organisms are pretreated with deoxyribonuclease suggests that the common microbial antigen is DNA. The isolated treponemal fluorescence found in syphilis is unaffected by pretreatment of T. pallidum. When 123 sera from patients with collagen disorders were examined, non-specific bacterial fluorescence was observed in six sera, while in 95 sera from patients with lepromatous leprosy, a positive FTA-ABS reaction was obtained in 14. There was no accompanying immunofluorescence on other protozoa. Therefore the antibody reacting in the FTA-ABS test in leprosy is likely to be treponemal in origin. A mitochondrial antibody was found in seven out of the 15 sera from patients with lepromatous leprosy.