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Biomedical subjects

J F Porter

Publications and source records attributed to J F Porter.

At least 19 recordsLinked to original sources
PubMed1996

Differentiation between human and ovine isolates of Bordetella parapertussis using pulsed-field gel electrophoresis.

The genetic relatedness of 18 human and 29 ovine isolates of Bordetella parapertussis was examined by macrorestriction digestion of DNA with the rarely cutting enzyme XbaI and resolution by pulsed-field gel electrophoresis. There was clear separation of human and ovine isolates and variation within host types. The human isolates were separated into three types as were the 24 Scottish ovine isolates. Species-specific bands were observed with the human isolates at 114, 134, 166, 213, 346 and 372 kb. No species-specific bands were found in the B. parapertussis ovine isolates. Isolates of B. parapertussis recovered from sheep in New Zealand gave a further two DNA banding patterns which were clearly different from the Scottish ovine and the human isolates. These results indicate that human and ovine isolates of B. parapertussis are genetically distinct and that variation exists within isolates from the same host species. Pulsed-field gel electrophoresis therefore appears to be a powerful discriminatory tool for the classification of B. parapertussis.

Animals↗
PubMed1996

Effects of interactions between Pasteurella haemolytica and Bordetella parapertussis on in vitro phagocytosis by lung macrophages.

The aim of the work was to determine the effect of exposing ovine bronchoalveolar macrophages (BAM) in vivo to Pasteurella haemolytica and/or Bordetella parapertussis on the subsequent uptake and killing of P. haemolytica by these cells in vitro. Exposure in vivo to P. haemolytica did not affect the uptake of P. haemolytica by BAM in vitro but reduced (P < 0.05) the intracellular killing of bacteria. Exposure in vivo to B. parapertussis had no significant effect on either the uptake or killing of P. haemolytica in vitro. However, sequential exposure in vivo to B. parapertussis and P. haemolytica reduced both the ingestion (P < 0.05) and killing (P < 0.001) of P. haemolytica in vitro. These results indicate that exposure to P. haemolytica compromised the bacterial killing mechanisms of BAM and that synergy between B. parapertussis and P. haemolytica reduced the ability of BAM to ingest bacteria.

Animals↗
PubMed1996

Moredun Bordetella Medium, an improved selective medium for isolation of Bordetella parapertussis.

Bordetella parapertussis, previously thought to be an obligate human respiratory tract pathogen, has been isolated from sheep. Attempts to assess the prevalence of B. parapertussis in conventionally reared sheep by nasal swabbing proved futile with existing selective media because of extensive overgrowth with Mucor spp. and other nasal commensals. Moredun Bordetella Medium (MBM), which contains cycloheximide and spectinomycin at final concentrations of 0.5 mg/ml and 100 mu g/ml, respectively, was developed as an improved selective medium to isolate B. parapertussis from the nasal cavities of conventionally reared sheep. The selective ability of MBM was evaluated with 200 nasal swabs from conventionally reared sheep, and B. parapertussis was recovered from 31.5% of the samples. MBM facilitated the simple and effective isolation of B. parapertussis from ovine nasal swabs and, in successfully excluding overgrowth with other contaminants, proved superior to other test formulations evaluated and to existing conventional media.

Bordetella↗
PubMed1995

Characterisation of ovine Bordetella parapertussis isolates by analysis of specific endotoxin (lipopolysaccharide) epitopes, filamentous haemagglutinin production, cellular fatty acid composition and antibiotic sensitivity.

Isolates of Bordetella parapertussis, recovered from sheep or man, were characterised by reaction with specific anti-Bordetella lipopolysaccharide monoclonal antibodies, production of filamentous haemagglutinin, fatty acid patterns, and antibiotic sensitivity. Generally, the isolates lay within one of four groups, with separation of the ovine isolates into two groups. Reactions with specific monoclonal antibodies against lipopolysaccharide separated the ovine isolates into these two groupings. Analysis of the cellular fatty acid compositions by cluster analysis differentiated between the human and the ovine strains and also showed variation within the ovine isolates. When the production of filamentous haemagglutinin was analysed in an ELISA system, a similar pattern emerged. Varying concentrations of filamentous haemagglutinin (11-429 ng (mg total protein)-1) were extracted from the human isolates and the one group of ovine isolates with no significant protein detected in the other ovine group. These studies demonstrate variation between and within B. parapertussis isolates recovered from two mammalian sources.

Adhesins, Bacterial↗
PubMed1995

Sexual aggression and victimization in dating relationships among Chinese college students.

Sexual victimization in dating relationships among female Chinese college students in Hong Kong was studied. Findings were compared to Chinese males' self-reports of sexual aggression. Nonstranger sexual victimization was common among Chinese female college students, especially for less intimate forms of sexual contact. Prevalence of sexual victimization was similar to that in North America for less intimate forms of contact but less prevalent for more intimate contact, including rape. A greater proportion of women than men reported the experience of several behaviors engaged in against a woman's will. These included kissing, and touching a woman's hand, knee, leg, or crotch.

Adult↗
PubMed1995

Bronchopneumonia in mice caused by Pasteurella haemolytica A2 after predisposition by ovine Bordetella parapertussis.

Initial intranasal inoculation of four to eight-week-old Swiss White mice with 7.5 x 10(6) colony forming units (cfu) of ovine B. parapertussis followed 30 min, three or five days, by intranasal inoculation with 1.4 x 10(5) cfu of Pasteurella haemolytica A2 resulted in a more severe infection pattern than when either agent was administered alone. Histopathological examination showed that inoculation with B. parapertussis alone caused a bronchopneumonia the severity of which was dependant upon the infecting dose. Bacteria were recovered up to 10 days after inoculation. P. haemolytica alone had no apparant pathogenic effect and was cleared from the lungs within 24 h. When both agents were given in combination the lesions were most severe when P. haemolytica was administered three days after B. parapertussis infection. These findings suggest that B. parapertussis predisposes mice to subsequent infection with P. haemolytica and that the timing of the P. haemolytica administration influences the severity of the lung lesions.

Animals↗
PubMed1995

Predisposition of specific pathogen-free lambs to Pasteurella haemolytica pneumonia by Bordetella parapertussis infection.

Three groups of specific pathogen-free (SPF) lambs were inoculated intratracheally with an ovine isolate of Bordetella parapertussis (5.5 x 10(9) colony-forming units) or with B. parapertussis followed 2 or 5 days later with Pasteurella haemolytica serotype A2 (120-180 million colony-forming units). When P. haemolytica A2 was administered 2 days after infection with B. parapertussis all lambs became febrile for at least 72 h. At necropsy their lungs were discoloured, congested and showed large areas of collapse and consolidation which, in one case, covered the entire lung. Histopathological examination confirmed that the combined infection produced a severe acute bronchopneumonia in four of seven lambs. B. parapertussis and P. haemolytica were recovered from all of the lambs in this group. Seven lambs challenged with P. haemolytica 5 days after B. parapertussis and six lambs infected with B. parapertussis alone showed no clinical signs of disease other than mild pyrexia and only mild histopathological changes. B. parapertussis, but not P. haemolytica, was recovered from these lambs. The findings indicated that B. parapertussis predisposed the SPF lambs to P. haemolytica pneumonia. This effect appeared to be dependent upon the time interval between the administration of the two agents.

Animals↗
PubMed1994

Isolation and characterization of Bordetella parapertussis-like bacteria from ovine lungs.

Bacteria resembling two Bordetella species were isolated from both normal and pneumonic ovine lungs using a selective charcoal agar. Twenty-eight of the 33 isolates showed similarities to stock NCTC B. parapertussis strains in their SDS-PAGE gel protein profiles, in their biochemical reactions and in causing browning on tyrosine agar. Five isolates behaved similarly to stock B. bronchiseptica strains, in being actively motile, in giving identical positive reactions in three out of four biochemical tests and in causing no colour change in tyrosine agar. Multilocus enzyme electrophoresis separated the isolates into two electrophoretic types distinguishable from those of stock B. parapertussis and stock B. bronchiseptica strains.

Animals↗
PubMed1994

Tracheobronchial washings from seven vertebrate species as growth media for the four species of Bordetella.

The four species of Bordetella differed in their ability to grow at 37 degrees C in membrane-filtered tracheobronchial washings (TBW) from seven vertebrate species, including their natural hosts. From washed inocula of approximately 2 x 10(3) colony-forming units per ml (cfu ml-1), Bordetella bronchiseptica and B. avium grew much better than the other two bordetellae and yielded stationary-phase cultures containing 10(8)-10(9) cfu ml-1 in most of the TBW samples. These counts were only moderately lower than those attained in CL medium which contains about a 450-times higher concentration of amino acids. B. bronchiseptica and B. avium also grew to a limited extent in phosphate-buffered saline without nutrient supplements. B. parapertussis grew in TBW from man, sheep, rabbit, mouse and chicken, but not in TBW from a dog and a horse or in PBS. B. pertussis grew well in CL medium, but not in PBS or in any of 13 samples of TBW from the seven vertebrate species, which included three samples of lung lavage fluid from human patients. Analysis of the TBW samples for known Bordetella nutrients revealed concentrations of amino acids and nicotinic acid averaging 0.35 mM and 0.56 microgram ml-1 respectively.

Amino Acids↗
PubMed1993

Long-term survival of Bordetella bronchiseptica in lakewater and in buffered saline without added nutrients.

Bordetella bronchiseptica grew from small inocula, and retained viability for at least 24 weeks, in unsupplemented lakewater or phosphate-buffered saline. From washed inocula of around 10(3) colony-forming units/ml, there was growth at both 10 degrees C and 37 degrees C to give 10(6)-10(7) colony-forming units/ml. At 10 degrees C, these counts were maintained with little diminution up to week 24 when observations ceased. In the tests at 37 degrees C, two of three strains tested showed similar retention of viability. These results suggest that B. bronchiseptica may exist as hitherto unsuspected reservoirs of infection in freshwater habitats.

Bordetella bronchiseptica↗
PubMed1992

Measurement of sexual aggression in college men: a methodological analysis.

Researchers have devoted increased attention in recent years to the measurement of sexual aggression in college populations. This review describes and critically examines current methods of measuring sexual aggression which rely on a self-reported history of such behavior. We suggest that the construct validity of these approaches can be enhanced through a systematic consideration of instrumentation and methodological issues. Twenty-six empirical studies were evaluated with regard to sample characteristics such as size, type, representativeness, and subject exclusion criteria, as well as study design, measurement method, statistics reported, use of debriefing, and control for socially desirable response bias. Specific instrumentation methodology to measure a self-reported history of sexual aggression was examined in detail.

Adult↗
PubMed1992

Sexual and aggressive motives in sexually aggressive college males.

The relative contributions to sexual aggression of general sexual and aggressive motives and their respective inhibitory factors were compared. One hundred forty-three university males responded to self-report measures of sexual and aggressive drives, sex and hostility guilt, social desirability response bias, and history of coercive sexuality. With the effects of social desirability controlled, the only predictor of sexual aggression was Sex Guilt, which predicted level of force used but not intimacy of the sexual act obtained.

Adolescent↗
PubMed1991

Growth and survival of Bordetella bronchiseptica in natural waters and in buffered saline without added nutrients.

Bordetella bronchiseptica showed increases in viable count when incubated in phosphate-buffered saline (PBS), in reagent-grade water, and in local lake and pond waters, all without added nutrients. Within 48 to 72 h at 37 degrees C in PBS and in lake and pond waters, stationary-phase populations of around 2.7 x 10(6) CFU/ml developed from washed B. bronchiseptica inocula of around 2 x 10(3) CFU/ml. Increases in CFU on the order of five- and eightfold, respectively, were observed in reagent-grade water and in seawater from the same sizes of inocula. The organisms remained viable for at least 3 weeks in PBS and in lake waters at 37 degrees C. The possibility that carry-over of nutrients was responsible for growth was discounted by showing serial transfer of B. bronchiseptica in PBS under conditions in which Escherichia coli tested in parallel rapidly died out.

Bordetella↗
PubMed1988

The AI/RHEUM knowledge-based computer consultant system in rheumatology. Performance in the diagnosis of 59 connective tissue disease patients from Japan.

AI/RHEUM is a knowledge-based computer consultant system for the diagnosis of rheumatic diseases. Its diagnostic accuracy was evaluated using information that was supplied by Japanese rheumatologists on 59 patients with connective tissue diseases. The diagnoses of the AI/RHEUM model were in full or partial agreement with those of the Japanese rheumatologists in 54 of 59 cases (92%). Preliminary evaluation of the criteria tissue disease showed a sensitivity of 90% and a specificity of 96%.

Artificial Intelligence↗
PubMed1986

Developmental toxicity of N,N1-bis(dichloroacetyl)-1,8-octamethylene diamine: effects of in utero exposure on the postnatal murine immune system.

Oral gavage of pregnant C57BL/6J mice with N,N1-bis(dichloroacetyl)-1,8-octamethylene diamine on day 10 of gestation alters the morphology of a primary lymphoid organ, i.e., thymus, of the offspring when observed at 36 days of postnatal life. Thymuses obtained from the experimental offspring exhibited an overall reduction in size and cortical hypoplasia. Morphology of the spleen, a secondary lymphoid organ, is also affected in the offspring obtained from dams treated with this compound on day 10 of gestation. Spleens exhibited diffusely distributed white pulp areas compared to the distinctly nodular appearance in control spleens. Furthermore, it has been shown for the first time that prenatal administration of N,N1-bis(dichloroacetyl)-1,8-octamethylene diamine on day 12 of gestation alters the functional responsiveness of splenocytes obtained from the offspring of treated dams to a variety of mitogens when examined at 3, 5, 9 and 16 weeks of postnatal life. Administration of the compound prenatally on day 12 of gestation did not alter the postnatal morphological appearance of either thymus or spleen.

Abnormalities, Drug-Induced↗
PubMed1985

Longitudinal assessment of immunologic abnormalities of mice with the autosomal recessive mutation, "wasted".

Mice homozygous for the autosomal recessive mutation wasted (wst/wst) undergo a progressive wasting beginning at the third week of postnatal life, when body weight declines in the mutants. The wst/wst mice do not survive past 30 days of age. The present report describes histologic and functional abnormalities in a longitudinal analysis (17 to 29 days postpartum) of wst/wst mice. In addition to a marked age-dependent decline in wst/wst body weight as well as spleen and thymus wet weight to body weight ratios, we have observed a significant decline in spleen and thymus cell number in these organs, compared with phenotypically normal (+/+ or +/wst) littermates. Histologic analysis of the wst/wst thymus revealed marked cortical pyknosis at 23 days of age and significant cortical depletion by 26 days postpartum. The wst/wst spleen at 23 days of age and later was characterized by a marked reduction in the content of red pulp. Lymphoproliferative responsiveness to Con A was markedly altered in the wst/wst thymus and spleen, in an age-dependent fashion, compared with normal littermates. The wst/wst spleen LPS responsiveness was also markedly altered in an age-dependent fashion. Hypotheses are presented concerning the possible site(s) of gene action in the wst/wst mutant which may mediate the observed morphologic and functional abnormalities.

Age Factors↗
PubMed1976

Homosexuality treated adventitiously in a stuttering therapy program: a case report presenting a heterophobic orientation.

The heterophobic orientation toward treatment of homosexuality is discussed. A case report is presented where homosexuality apparently "spontaneously remitted" and heterosexuality was instated while the patient underwent treatment for stuttering. The change in sexual orientation is interpreted as possibly adventitiously induced through generalization effects from treatment of the relevant phobic aspects of the stuttering problem to the associated social aspects of the sexual problem.

Adult↗