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PubMed1996

Immunological studies on venereal spirochetosis of rabbits (rabbit syphilis).

White rabbits in a family, which were clinically diagnosed as moderately or severely diseased with spirochetosis, were bacteriologically and immunologically examined. The specimens from the diseased rabbits, including affected prepuces, scrotum, or skins with an occasional presence of the spirochetes, did not, however, result in growth in six conventional culture media. Serological tests, including quantitative complement fixation test, rapid plasma reagin card test, Treponema pallidum hemagglutination test, and microscopic agglutination test for leptospires using sera from diseased rabbits showed no differences when compared with those of pooled normal rabbit sera. Immunoblot analysis of the polypeptides from three human oral treponemes and three non-oral spirochetes demonstrated that antibodies against several treponemal polypeptides were detected.

Animals↗
PubMedDate not supplied

Genetic variation for dorsal-ventral patterning of the Drosophila melanogaster eggshell.

Patterning of the insect eggshell is an excellent system for exploring the molecular basis of phenotypic variation. In Drosophila melanogaster, two dorsal-anterior respiratory appendages are produced in response to signaling through the Epidermal growth factor receptor (Egfr). Previous work implicates Egfr pathway function in both intraspecific variation for dorsal appendage spacing (DAS) on the eggshell, as well as interspecific differences in dorsal appendage number and location. To test the hypothesis that genetic variation in Egfr contributes to variation in eggshell patterning, we have made use of naturally occurring intraspecific variation for DAS as a model quantitative trait. We found that there is substantial segregating genetic variation for DAS in D. melanogaster, and have tested for associations with 289 common polymorphisms in the Egfr locus. A marginal association was seen with two polymorphic sites in Egfr; however, we failed to replicate these findings in a second population, or in a modified quantitative complementation test designed to specifically test the effects of the putative polymorphisms. Therefore, we conclude that the polymorphisms we have identified in Egfr do not contribute to variation in DAS, and further work is required to understand the genetic architecture of this trait.

Animals↗
PubMed1975

Yersinia pestis: correlation of ultrastructures and immunological status.

Ultrastructural identification and localization of the fraction 1 "envelope" antigen in the plague bacillus Yersinia pestis were the primary objectives of this brief study. The antigenicity of extra-cellular material between the bacilli in undisturbed cultured colonies and that of the pathogen per se were measured and correlated by means of the semi quantitative complement fixation method after incubation for 72 h at 37 C. When the amount of extracellular substance in wild-type T1 (virulent) bacteria was compared by electron microscopy with that in avirulent strains of Y. pestis, with and without passage through guinea pigs, we found that the material of interest was greatly attenuated or even absent in colonies that had not been passed through animals, whereas passage markedly augmented production of the material. We also explored the requirement for larger quantities of Ca(2+) and Mg(2+) in the culture media and discovered that without these ions production of the extracellular material was limited. These observations support the hypothesis that this extracellular substance between cultured Y. pestis bacilli of various strains represents the source of the fraction 1 envelope antigen.

Antigens, Bacterial↗
PubMed1973

Genetic study of suppressor-sensitive mutants of the Bacillus subtilis bacteriophage phi 29.

With bacteriophage phi29 of Bacillus subtilis 133, suppressor-sensitive (sus) hydroxylamine mutants have been isolated. Intracistronic and intercistronic quantitative complementation placed the mutants in 13 cistrons, and three-factor crosses have been used to assign an unambiguous order for 10 cistrons. Recombination frequencies have been presented for several regions of the genome to facilitate comparison of the sus system with the previously published temperature-sensitive mapping systems.

Bacillus subtilis↗
PubMed1974

Murine type-C virus group-specific antigens: interstrain immunochemical, biophysical, and amino acid sequence differences.

The 30,000-molecular-weight internal protein, p30, was purified from seven strains of mouse type-C viruses. The individual p30's showed variation in isoelectric points and also intrastrain heterogeneity. The individual p30's could be distinguished by peptide map and quantitative complement fixation techniques with relatedness estimates of >95%. Amino terminal sequence analysis showed variability at position 4 for several p30's with complete homology otherwise through 24 residues. The intrastrain heterogeneity in p30 isoelectric points could not be explained by common contaminants, as shown by peptide mapping, and is more likely based on post-transcriptional modifications. These data provide a chemical basis for the recently described type-specific immunological properties of individual p30's.

Amino Acid Sequence↗
PubMed1976

Genetic analysis of bacteriophage phi 29 of Bacillus subtilis: integration and mapping of reference mutants of two collections.

Reference mutants of Bacillus subtilis phage phi 29 of the Madrid and Minneapolis collections were employed to construct a genetic map. Suppressor-sensitive and temperature-sensitive mutants were assigned to 17 cistrons by quantitative complementation. Three-factor crosses were used to assign an unambiguous order for the 17 cistrons. Recombination frequencies determined by two-factor crosses were used to construct a linear genetic map of 24.4 recombination units. The genes were numbered sequentially from left to right (1 to 17) according to their relative map position.

Bacillus subtilis↗
PubMed1989

Identification of factors specific for transcription of the late class of vaccinia virus genes.

Cytoplasmic extracts made from HeLa cells that have been harvested late after infection with vaccinia virus are capable of specifically transcribing templates containing vaccinia virus late-gene promoters. We applied such an extract to a phosphocellulose column and eluted the proteins with a series of buffers containing successively higher concentrations of NaCl. None of three column fractions alone was capable of specific transcription of a late-gene template. However, specific transcriptase activity could be reconstituted by mixing column fractions, with maximal activity seen when all three fractions were present. The activities present in all fractions were heat labile, resistant to micrococcal nuclease, and present only in extracts from vaccinia virus-infected cells. A quantitative complementation assay was used to further purify one factor, named VLTF-1, over subsequent columns of DEAE-cellulose and hydroxylapatite. VLTF-1 was separated from endogenous RNA polymerase, was a late-promoter-specific transcription factor, and had a sedimentation rate consistent with an apparent Mr of 45,000. The RNA polymerase-containing fraction was not only necessary for transcription with a late-promoter template but alone was capable of specifically transcribing a vaccinia virus early-gene promoter. A further difference between early and late gene transcription in this system was in the ability of the ATP analog beta-8-imidoadenosine-5'-triphosphate (AMP-PNP) to substitute for ATP in supporting specific transcription of only the late-promoter template. The system reconstituted from the various fractions retained the ability to produce the novel poly(A) sequence found on the 5' end of vaccinia virus late messages.

Adenosine Triphosphate↗
PubMed1994

Listening to local voices: adapting rapid appraisal to assess health and social needs in general practice.

OBJECTIVES: To explore the use of rapid appraisal in defining the health and social needs of a community and to formulate joint action plans between the residents and service providers. DESIGN: Collection of data by an extended primary care team from three sources: existing documents about the neighbourhood, interviews with a range of informants, and direct observations to build a profile of the community. SETTING: Council estate of 670 homes in Edinburgh. MAIN OUTCOME MEASURES: Perceived problems of the community and suggestions for change. RESULTS: The interviews and focus groups identified six priorities for change, many of which were not health related. These changes have been or are being implemented. CONCLUSIONS: An expanded primary care team can use rapid appraisal as a first step in identifying and meeting local health needs. It facilitates a multidisciplinary approach and complements quantitative methods of assessing need.

Community Participation↗
PubMed1967

Antibodies to native and denatured deoxyribonucleic acid in systemic lupus erythematosus.

The relative reactivities with native and denatured DNA of 35 lupus sera were investigated by quantitative complement fixation and precipitin studies and showed great variations. The use of purified native DNA demonstrated that, in at least 22 of these 35 sera, the anti-DNA antibodies reacted with the native form, independently of denatured contaminants. Systemic lupus sera were shown to contain three main types of DNA antibodies: those reacting only with denatured DNA, those reacting to the same extent with both forms of DNA, and those reacting preferentially with native DNA. In some instances, the latter antibodies fix complement and precipitate only with native DNA but are inhibited by the denatured form. This finding points to the importance of conformation in the antigenic structure of DNA. The simultaneous occurrence of different varieties of DNA antibodies was demonstrated in several sera. Evidence was obtained that some of these human antibodies to DNA can belong to the IgM class. Thus, DNA antibodies from systemic lupus patients differ in many respects from most of the experimentally produced antibodies capable of reacting with DNA.

Antibodies↗
PubMed1990

Nurses in resident evaluation. A qualitative study of the participants' perspectives.

This study complemented a large psychometric study using nurses to assess medical residents' humanistic behavior. It was designed to identify how nurses and residents defined humanistic qualities and behaviors and what factors affected their views of residents' performance and evaluation. The study also illustrates how qualitative methods were used to complement quantitative psychometric data and thereby yield a more complete assessment of the value of a new performance evaluation form. The results indicated that nurses' definitions of humanistic behavior often differed from residents', tending to reflect a broader perspective on the physician's role and responsibility in patient care. Nurses and residents disagreed about whether nurses were qualified to evaluate residents' humanistic behavior and about what nurses actually observed on the wards. Professional respect was an issue for both nurses and residents. The discussion section identifies some implications for resident training and nurse-resident relationships and supports the value of combining research strategies when evaluating complex human behavior.

Attitude of Health Personnel↗
PubMed2002

The psychosocial experience of people with sickle cell disease and its impact on quality of life: Qualitative findings from focus groups.

OBJECTIVES: In this exploratory study, an in-depth analysis of accounts of the experiences of people with sickle cell disease (SCD) was undertaken to gain an understanding of the psychosocial impact of the disease. An additional aim of the study was to determine whether these experiences could be conceptualized in terms of quality of life as defined by the World Health Organization (WHOQOL) with the intention of informing psychosocial research. DESIGN: This study utilized a series of non-directive, patient-led, focus groups that specifically addressed the ways in which sickle cell disease impacts on life. Participants were recruited from four centres in London and eight focus group discussions (each one hour in length) were held separately for each centre. METHOD: Altogether 32 hours of focus group materials were tape-recorded and transcribed verbatim. Data were analysed using a phenomenological approach to identify emerging themes. RESULTS: Six themes were identified: Growing up with SCD; Education; Impact of the unremitting nature of the disease; Employment; Effects on relationships; and Hospitalization. CONCLUSION: This research has clearly shown that SCD carries a huge psychosocial burden impacting on physical, psychological, social and occupational well-being as well as levels of independence and environment. These aspects of life are equivalent to the core domains of the multi-dimensional WHOQOL and consequently we have argued that SCD undermines quality of life in important ways. The paper provides a rich source of qualitative data to complement quantitative findings and provides detail of the complex human processes and experiences consequent on a life-long chronic illness such as SCD.

Journal Article↗
PubMed1970

Immunological factors which influence response to immunotherapy in malignant melanoma.

Antimelanoma antibodies previously demonstrated in the serum of melanoma patients by immunofluorescence have now been detected by a sensitive and quantitative complement fixation technique. The melanoma-specific antibodies detected by both of these techniques show a remarkable correlation with the stage of disease. Study of serums from 63 melanoma patients showed that both the incidence and titer of antibodies to the tumor antigens of malignant melanoma were found to be higher in patients with localized melanoma than in those with widespread metastatic disease. Furthermore, study of serial serum specimens on melanoma patients revealed a drop in antibody titer to undetectable levels with advancing metastatic disease. Additional evidence for the importance of immunological factors in this disease came from studies of delayed cutaneous hypersensitivity in melanoma patients. All patients with localized melanoma were capable of being sensitized to DNCB, whereas all patients who could not manifest delayed cutaneous hypersensitivity to this chemical had widespread metastatic disease. Eight melanoma patients were treated with immunotherapy using BCG as an immunological adjuvant. This therapy produced a rising titer of antimelanoma antibody and temporary tumor regression in five patients. However, only one of these patients has had a complete regression and remains free of disease at two years following treatment. There was a good correlation between the patient's immunological competence and his response to immunotherapy. All patients who could be sensitized to DNCB or tuberculin and developed a fourfold rise in antibody titer had some response to immunotherapy, whereas anergic patients failed to respond to this therapy. These studies indicate that the host immune response to malignant melanoma is an important factor in controlling the progression of this disease. Therefore, immunotherapy may become a useful adjunct to the primary surgical therapy of malignant melanoma.

Antibodies, Neoplasm↗
PubMedDate not supplied

[Nutrition surveillance: 25 years later].

Nutrition surveillance is a rather recent application of epidemiological surveillance to nutrition. It covers not only the morbidity and mortality of nutritional disorders, but is at least as much interested in their major determinants. After some fifteen years of trial and error, nutrition surveillance has today found its way: its concepts, methods and uses are well established by now. After retrieving experiences conducted since the seventies and the eighties, and on the basis of their own experience, the authors have come to identify a few major features of nutrition surveillance: predominance of the supply of information over the collection of data; the early identification of users; the importance of causal analysis as a departure point for conceiving a surveillance activity; the highly selective choice of data to be collected; a permanent concern for sustainability; the participation of all actors (or "stakeholders") and, from a technical viewpoint, the place of qualitative data collection techniques (borrowed from social anthropology) to complement quantitative data. The authors summarize the major steps followed in the design and implementation of a nutrition surveillance activity, emphasizing the benefits of a careful and in-depth preparation during the so-called "pre-surveillance" phase.

Data Collection↗
PubMed2006

[Numbers are also words].

The author, leaving aside his development as a statistician, opens up to other proposals, reviewing some studies about qualitative research methodology as related to health sciences. He concludes that qualitative research complements quantitative research and that a subjective element exists in both: numbers are also words because behind numbers there is a reflexive process and a human interpretation.

Qualitative Research↗
PubMed1988

[The value of resorting to 2 technics for detecting anti-mitochondrial antibodies].

The presence of antimitochondrial antibody was determined by an indirect immunofluorescence assay (IIFA) and a quantitative complement fixation test (CFT) in 2,302 sera. This survey enabled us to calculate the sensitivity, specificity, positive and negative predictive values of the two techniques. It seemed valuable to use both techniques as the IIFA was more sensitive than the CFT whilst the CFT was more specific than the IIFA.

Antibodies↗
PubMed1988

Purification of a factor required for transcription of vaccinia virus early genes.

Partially purified DNA-dependent RNA polymerase from infectious vaccinia virus particles exhibits the following two activities: 1) specific transcription of double-stranded DNA templates containing vaccinia early promoters and 2) nonspecific transcription of single-stranded DNA templates. After further purification of the RNA polymerase, specific transcriptase activity was selectively diminished suggesting the loss of a transcription factor. In agreement with the latter hypothesis, transcriptase activity could be reconstituted by mixing the purified RNA polymerase with certain column fractions. A quantitative complementation assay was developed and used to locate the transcription factor during successive column chromatography steps. The factor eluted as a single peak of activity from single strand DNA-cellulose and phosphocellulose columns. An observation that the transcription factor binds specifically to vaccinia early promoter sequences was exploited in the final affinity chromatography steps. The purified factor was separated from all previously identified vaccinia enzymes and contained two polypeptides of Mr 77,000 and 82,000. A DNA-dependent ATPase activity also copurified with the transcription factor. Although a single template was used for assays during isolation, the purified factor stimulated transcription of three other early genes by 20-30-fold suggesting that it has a general role in conferring promoter specificity for initiation of early transcription.

Chromatography, Affinity↗
PubMed1975

Antigenic determinants of bovine myelin encephalitogenic protein recognized by rabbit antibody to myelin encephalitogenic protein.

The antigenic determinants of bovine myelin encephalitogenic protein were investigated by quantitative complement fixation and hapten inhibition using rabbit anti-monkey protein and anti-bovine protein and purified and characterized fragments of bovine protein. The two regions of bovine encephalitogenic protein containing determinants were sequences 1 to 43 and 90 to 170. One rabbit antiserum recognized a determinant(s) probably in residues 15 to 40 while for another rabbit antiserum the determinant of 1 to 43 resided in 1 to 20. The determinant(s) of residues 90 to 170 involved the region around the tryptophan at position 116. Fragment 44-89, which contains the major encephalitogenic determinant for the rabbit, was virtually devoid of any reactivity with the rabbit anti-encephalitogenic protein. It appears that portions of the protein other than the encephalitogenic site are responsible for stimulation of bone marrow-derived cells and antibody production. In demonstrating selected regions of the protein as sites for antigenic determinants, the present immunochemical studies also suggest that the protein might have a more folded conformational alignment than previously suspected.

Amino Acids↗
PubMed1981

Hyperthyroidism and polycythemia vera with chronic urticaria and angioedema.

Of 154 patients with chronic urticaria, six manifested concomitant hyperthyroidism and four polycythemia vera. Investigations of serum IgE, immune complex quantitation, complement and skin biopsies failed to elucidate a causal relationship. Polycythemia vera and hyperthyroidism should be considered as possible associations in the evaluation of chronic urticaria.

Angioedema↗