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Biomedical subjects

J D Anderson

Publications and source records attributed to J D Anderson.

At least 127 records · Page 7Linked to original sources
PubMed1981

Appraisal of disk sensitivity tests with mecillinam.

Disk susceptibility tests for mecillinam were carried out on 167 hospital isolates of Enterobacteriaceae from Vancouver. Inhibition zone sizes with eight experimental variations were compared by three-way analysis of variance. The Association of Clinical Pathologists' method gave significantly (p = 0.0002) larger zones than the Kirby Bauer method (24.9 +/- SD 7.5 and 23.4 +/- 7.3 mm, respectively). 10 microgram mecillinam disks from Mast Laboratories gave significantly (p = 0.0004) larger zones than the Baltimore Biological Laboratories (BBL) equivalent (24.9 +/- 7.6 and 23.4 +/- 7.2 mm, respectively). Differences between Oxoid Iso-sensitest agar and BBL Mueller Hinton agar were not quite significant (24.5 +/- 7.9 and 23.8 +/- 6.9 mm, respectively, p = 0.061). Each disk test method was significantly different from at least one other (Duncan multiple range test, alpha = 0.05). A semilogarithmic regression was established between the antibiotic disk inhibition zone and the MIC for each experimental variation. BBL Mueller Hinton and Oxoid Iso-sensitest media did not give significantly different results in MIC determinants by a surface inoculation method. An additional 146 organisms from hospitals in New York provided a wider range of organisms from a different location. Pooled data from both centres were used to identify breakpoints for mecillinam in the disk susceptibility test using the Kirby Bauer method with BBL disks and media. A 16-mm breakpoint with 10 microgram mecillinam disks provides a realistic and conservative prediction of probable response to attainable serum concentrations of this antibiotic.

Amdinocillin↗
PubMed1980

Fusidic acid: new opportunities with an old antibiotic.

The extensive foreign experience with fusidic acid prior to its belated introduction to Canada is reviewed. Fusidic acid is a steroid antibiotic with minimal toxic and hormonal effects that is mainly excreted through the liver. It has a predominantly bactericidal action and does not shown cross-resistance with other antibiotics. Since organisms resistant to this drug form easily in vitro when exposed to low concentrations, complementary treatment with another antibiotic may be required in some clinical situations. Although fusidic acid is active in vitro against a number of organisms, to date it has mainly been used to treat serious infections due to Staphylococcus aureus. The agent appears to be particularly valuable in the treatment of bone and joint infections and in pediatric practice. Fusidic acid will soon be available in Canada for both oral and intravenous administration. Attainable antibiotic levels in many tissues and body fluids greatly exceed the minimum inhibitory concentrations.

Anti-Bacterial Agents↗
PubMed1980

The in situ cellular immune response in BALB/c mice jejunum disseminated lymphoid tissue after stimulations with E. coli endotoxin.

The feasibility of the functional ultrastructure, a term used to describe the in situ immunocumpetent cell topography, B-cell transformation, multiplication and cell-to-cell interactions, was only recently made possible (Toma et al. 1977a; Toma and Retief 1978). The functional ultrastructure of the BALB/c mice jejunum disseminated lymphoid tissue (JDLT) before and after four i.p. sequential stimulations with 5 ng E. coli endoxin (ECE) each revealed the following results: 1. The in vitro T-cell response was found to be by recruitment and not by the in situ cell division. T-lymphocyte recirculation in the thymus may be the answer to the question "Where does the clonal proliferation occur?" 2. Two T-cellular immune responses have been identified, one occurring early during the stimulation (1st and 2nd stimulations) and the other occurring late (after the 4th stimulation with ECE). It was thought that the first T-cell response represented the helper type of the immune response, whereas the second would represent the suppressor T-cell response. 3. The B-cell response, as judged from the percentage of plasma cells (PC) generated, was strong in the T-PC islands but no patterns of its generation could be established. 4. The curious topography of the immunocompetent cells inside the T-PC islands in the Lieberkühn crypts was found and their origin discussed. We aimed to establish the physiology of the cellular immune response in JDLT and to use it as a normal comparative model. It will be compared with the pathology of immune response in this part of BALB/c mouse gut established by immunosurveillance and tumorigenesis in artificially induced plasmacytomas with mineral oil (the following article).

Animals↗
PubMed1980

I. Immunosurveillance and tumorigenesis in 1. BALB/c mice. Early reactive state in the jejunum disseminated lymphoid tissue.

Using functional ultrastructure we established the physiology of the cellular immune response in the BALB/c mouse jejunum disseminated lymphoid tissue (JDLT) before and after sequential stimulations with E. coli endotoxin (ECE) (the preceding article in this journal). The functional ultrastructure was established also in this series of BALB/c mice injected i.p. initially with 0.5 ml of mineral oil and then weekly with 5 ng of ECE (EOA). The present series of mice had a pathological immune response and, it is known that they will in time produce plasmacytomas. Differences between the physiologic and pathologic immune responses during the first month of tumorigenesis, are: 1. The T-lymphocyte response was found to be strong but disorganized; 2. As judged from the T:B ratios, the B-lymphocyte response was found to be very strong, late after the first, early after the second, and late after the fourth injections with ECE, in this EOA model of stimulation. 3. The macrophage cellular response during the EOA stimulation was found to be slightly weaker than that seen in the series of mice stimulated with ECE alone. At the time of this study, the differences found between the physiologic and pathologic immune responses in the JDLT are not conclusive and they do not elucidate either the mechanisms of tumorigenesis or the role of the immunocompetent cells.

Animals↗
PubMed1980

Test-retest reliability of the test for auditory comprehension of language when it is used with mentally retarded children.

The Carrow (1973) Test for Auditory Comprehension of Language (TACL) is used frequently as part of a test battery to assess the language skills of mentally retarded children. This study determined its reliability with this population using a test-retest paradigm. Forty-four retarded children were given the test and then retested after a five-week interval. A reliability coefficient of 0.91 was obtained between pre-test and posttest administrations of the TACL. Internal stability was highest for total scores, the subtests measuring form class and function words, and grammatical categories. The low coefficients obtained for the subtests of morphological construction and syntactic suggest that these should be viewed with considerable caution when considered separately from the total test results.

Adolescent↗
PubMed1980

Comparison of amoxicillin and ampicillin activities in a continuous culture model of the human urinary bladder.

Sixteen isolates of Escherichia coli were obtained from women with significant acute urinary tract infections who were subsequently treated with amoxicillin. The activities of amoxicillin and ampicillin against these organisms were compared in urine in a continuous culture apparatus which partly simulated the milieu of the human urinary bladder. After introduction of amoxicillin into the bladder model, mean viable counts for 14 susceptible strains (minimum inhibitory concentration less than or equal to 32 microgram/ml) at 10, 20, 30, and 45 min fell to 34, 8, 0.4, and 0.2% of the original. Corresponding figures for ampicillin were 56, 24, 11, and 2.4%. Viable counts obtained at seven timed intervals up to 2 h were significantly (P = 0.025) lower with amoxicillin than ampicillin. Both antibiotics had a similar activity in conventional disk susceptibility and surface plate minimum inhibitory concentration tests. The realism of the model was confirmed by comparing response to amoxicillin in vivo and in vitro. A serious discrepancy was seen in only one of the 16 cases.

Acute Disease↗
PubMed1980

Plasma cell leukaemia. Diagnostic problems in our experience with 11 cases.

11 patients with plasma cell leukaemia (PCL) are reported. Diagnostic clinical, haematological, immunological, biochemical and electron microscopical (TEM) data were analysed and compared to the largest series of PCL cases reported in the literature. Special attention was paid to four facets of this disease: (a) the clinical picture at admission; (b) the frequency of PCL; (c) the production of M components in relation to the maturity and type of the asynchronous plasma cells, and (d) the diagnostic problems of this entity of acute leukaemia of the afferent limb of the B lymphocyte transformation. In this series PCL emerges as a distinct clinical entity: patients are severely anaemic, hepatosplenomegaly is prominent, bone lessions are uncommun, but if present are usually non-osteolytic, and the response to treatment with an alkylating agent and glucocorticoid is poor. The diagnosis is difficult since the circulating plasma cells may have morphological features which only allows the diagnosis to be made after the TEM examination. If the peripheral blood of cases of acute leukaemias and immunocytic dyscrasias is routinely examined by TEM, PCL appears to be a not uncommon variant of plasma cell dyscrasia--in the present study it was 11%.

Adult↗
PubMed1979

Postmenopausal endometriosis: A case report.

A case of postmenopausal endometriosis is presented. Symptoms started 14 years after total abdominal hysterectomy and bilateral salpingo-oöphorectomy for endometriosis following oestrogen administration. The disease had a protracted course and eventually responded well to radiotherapy. Certain aspects of postmenopausal endometriosis are discussed.

Endometriosis↗
PubMed1979

Incidence of ovarian neoplasms at the Bloemfontein Academic Hospitals, 1972-1977.

In the Orange Free State patients with gynaecological tumours are mainly referred to the National and Pelonomi Hospitals and the Department of Oncotherapy. During the 6 years 1972-1977 there were 1 895 admissions to the gynaecological wards of the National Hospital and 9 807 admissions to those of the Pelonomi Hospital. A total of 205 cases of primary ovarian neoplasia was seen, comprising 97 Whites and 108 Blacks. These cases were further divided into benign and malignant tumours and histologically classified into four main groups. Comparisons were made between cases seen in Bloemfontein and cases at other institutions.

Female↗
PubMed1979

Is the d an allelic gene of D in the Rh blood group system? A quantitative study using 99mTechnetium-pyrophosphate-labelled antibody (TcLA) method.

This article reports on studies of Rh antigens, such as D, Du and d, using uranyl-labelled antibody (ULA) and TcLA (99mTc-pyrophosphate-labelled antibody) methods for the first time for this purpose. TcLA method proved to be simple in labelling and very sensitive (20--100 times more so than the indirect Coombs test) in the detection of Rh antigen-antibody binding. Results of this quantitative study demonstrate convincingly that the d is not an allelic gene of D but rather the weakest of the series D less than Du less than d. Although the evidence from this study demonstrates clearly that differences between D and d are only quantitative, the authors do not think that the Rh nomenclature should be changed but they do think that the present evidence should be used in regard to the understanding of the allelism in the Rh blood group system. The c is an allelic gene of C as the e is an allelic gene of E; specific test sera detecting every one of these antigens exist and the family studies verify these statements. However, the d is not a distinct antigen as c and e are, even if the pattern of inheritance from family studies, using the existent anti-D serum, would suggest the allelism as probability. That is why in the past the anti-Du and anti-d specific test sera never incidentally found or artificially produced.

Alleles↗
PubMed1979

Purine nucleotide metabolism of germinating soybean embryonic axes.

Isolated soybean (Glycine max L. cv. Kent) embyronic axes metabolized [(14)C]glycine to ATP within the 1 hour of imbibition. Radioactivity was not detected in GTP until the 3rd hour. Throughout most of the first 24 hours of germination about 10 to 26 times as much label from [(14)C]glycine appears in ATP as GTP. About five times as much [(14)C]hypoxanthine and [(14)C]inosine was converted into GTP as into ATP in embryonic axes. Two independent pools of IMP appear to be used in purine nucleotide synthesis of soybean axes.

Journal Article↗
PubMed1979

Ethylene production by apple protoplasts.

Freshly prepared protoplasts from apple tissue that produced ethylene were obtained. Ethylene production was inhibited by osmotic shock, 0.01% Triton X-100, and aminoethoxyvinyl glycine. Protoplasts as well as the ethylene system were not greatly affected by protease treatment.

Journal Article↗
PubMed1979

Characterization of the Phosphate-mediated Control of Ethylene Production by Penicillium digitatum.

Characterization of the phosphate effect on ethylene production by Penicillium digitatum is reported. A low level of phosphate (0.001 millimolar) was about 200 to 500 times as effective as a high phosphate level (100 millimolar) in stimulating ethylene production and the stimulation was readily reversed by addition of phosphate. This phosphate effect did not operate in static cultures. The precursor of ethylene in the stimulated low phosphate system was glutamate but not alpha-ketoglutarate, which is a precursor in static systems. Actinomycin D and cycloheximide effectively inhibited the low phosphate/high ethylene-producing system. Alkaline phosphatase and protein kinase activities were higher in low than in high phosphate systems. We suggest that phosphate level regulates ethylene production by P. digitatum and that the regulation involves a phosphorylation or dephosphorylation reaction of some enzyme system associated with ethylene production. Phosphate-mediated control of ethylene production may also involve the transcriptional and translational machinery of the fungal cell. P. digitatum apparently can produce widely different levels of ethylene by different pathways, depending on culture conditions under which it is grown.

Journal Article↗
PubMed1979

Influence of enol ether amino acids, inhibitors of ethylene biosynthesis, on aminoacyl transfer RNA synthetases and protein synthesis.

The analogs of rhizobitoxine, aminoethoxyvinylglycine (AVG) (l-2-amino-4-2'-aminoethoxy-trans-3 butenoic acid) and methoxyvinylglycine (MVG) (l-2-amino-4-methoxy-trans-3-butenoic acid), that are potent inhibitors of ethylene biosynthesis at 0.1 millimolar also inhibited protein synthesis and charging of tRNA especially at 1 millimolar and higher concentrations. The saturated analog of MVG inhibited ethylene synthesis while the saturated analog of AVG did not. Both saturated AVG and MVG inhibit methionyl- and leucyl-amino acyl-tRNA synthetase. Because of the inhibition of amino acid metabolism in plant tissues by these rhizobitoxine analogs caution is advised in interpreting the results obtained with concentrations of compounds above 0.1 millimolar.

Journal Article↗