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B Anderson

Publications and source records attributed to B Anderson.

At least 19 recordsLinked to original sources
PubMed1992

Salmonella mutagenicity tests: V. Results from the testing of 311 chemicals.

311 chemicals were tested under code, for mutagenicity, in Salmonella typhimurium; 35 of the chemicals were tested more than once in the same or different laboratories. The tests were conducted using a preincubation protocol in the absence of exogenous metabolic activation, and in the presence of liver S-9 from Aroclor-induced male Sprague-Dawley rats and Syrian hamsters. Some of the volatile chemicals were also tested in desiccators. A total of 120 chemicals were mutagenic or weakly mutagenic, 3 were judged questionable, and 172 were non-mutagenic. The remaining 16 chemicals produced different responses in the two or three laboratories in which they were tested. The results and data from these tests are presented.

Animals↗
PubMed1992

An inside-out theory of attention.

The brain has two attentional systems; one attentional system is devoted to intrapersonal space and the second attentional system to extrapersonal space. The development of these two attentional systems with inward or outward focus arose from the hemispheral neural systems designed for attending to extrapersonal contralateral space. As a necessary consequence of the brain changes to develop language, one of the hemispheral attentional systems was altered for intrapersonal attention while the other hemispheral attentional system became obligated to attend to all of extrapersonal space. This conceptualization of attention provides a coherent explanation for the confusing hemispheral dominance proposed for attention on the basis of clinical hemineglect, i.e. that the left hemisphere attends to right extrapersonal space and that the right hemisphere attends to both left and right extrapersonal space. This conceptualization also provides a meaningful account of denial of limbs (anosognosia) and imagery.

Animals↗
PubMed1992

Extended field irradiation for carcinoma of the uterine cervix with positive periaortic nodes.

Forty-three patients were treated with extended field irradiation for periaortic metastasis from carcinoma of the uterine cervix (FIGO stages IB-IV). Twelve patients (28%) remained continuously free of disease to the time of analysis or death from intercurrent disease, 20 (46%) had persistent cancer within the pelvis, 11 (26%) had persistent periaortic disease, and 23 (53%) developed distant metastasis. The actuarial 5-year survival rate was 32%. The results correlated well with the periaortic tumor burden at the time of irradiation. None of 19 patients (0%) with microscopic or small (less than 2 cm) periaortic disease had periaortic failures, compared to 29% (4/14) of those with moderate-sized (2-5 cm) disease and 70% (7/10) of those with massive (greater than 5 cm) periaortic metastasis. Similarly, the 5-year survival rates were 50% (6/12) with microscopic disease, 33% (2/6) with small gross disease, 23% (3/13) with moderate-sized disease, and 0% (0/10) with massive periaortic metastases. Only 10% (1/10) of patients whose tumor extended to the L1-2 level survived 5 years, compared with 31% (9/29) of those whose disease extended no higher than the L3-4 level. The periaortic failure rates correlated to some extent with the dose delivered through extended fields, although the difference was not statistically significant. Only 8% (1/13) of those who had undergone extraperitoneal lymphadenectomies developed small bowel complications, compared with 25% (7/29) of those who had had transperitoneal lymphadenectomies. The incidence of small bowel obstruction was 8% (1/13) following periaortic doses of 4000-4500 cGy, 10% (1/10) after 5000 cGy, and 32% (6/19) after approximately 5500 cGy. From this, we concluded that the subset of patients who would benefit most from extended field irradiation are those in whom the residual disease in the periaortic area measures less than 2 cm in size at the time of treatment, whose disease extends no higher than L3, and whose cancer within the pelvis has a reasonable chance of control with standard radiation therapy techniques.

Adult↗
PubMed1992

Dorsal penile nerve block in neonatal circumcision: chloroprocaine versus lidocaine.

Dorsal penile nerve blocking (DPNB) has been used with success in decreasing neonatal stress during circumcision. This study was designed to confirm the effectiveness of lidocaine in DPNB and to demonstrate that chloroprocaine, a shorter acting anesthetic, is as effective in blocking circumcision stress as lidocaine, but, because of its shorter plasma elimination half-life and time of onset of action, is safer. Five groups of 15 neonates were matched for weight, age, and Apgar scores and randomly assigned to a control group, one lidocaine group and three chloroprocaine groups with 2-, 3- and 5-minute postinjection waiting periods. Each neonate was subjected to six events during circumcision for which heart rate, tissue oxygenation, and cry duration were recorded. We found that, as in previous investigations, DPNB with lidocaine was effective in reducing neonatal stress, as was evident from decreased excursion from baseline heart rate, tissue oxygenation, and cry duration when compared with the control group (nonblocked). Furthermore, chloroprocaine DPNB approximates the effectiveness of lidocaine, as was evident from decreased change from baseline cry duration, tissue oxygenation, and heart rate during the most stressful events, particularly in the 3-minute wait chloroprocaine group. This more rapid onset of regional anesthesia decreases DPNB circumcision time and benefits patients, parents, and physicians.

Anesthetics, Local↗
PubMed1992

Interaction of tricyclic antidepressants with cholestyramine in vitro.

The adsorption of amitriptyline, desipramine, doxepin, imipramine, and nortriptyline onto cholestyramine was demonstrated in vitro with use of 1.2 mol/L HCl at 37 degrees C to simulate gastric fluid. Binding to cholestyramine was approximately 80% for each of the tricyclic antidepressants, and this was about the same degree of binding noted with a nonpharmaceutical, non-ionic resin widely used in the diagnostic toxicology laboratory (Amberlite XAD-2). In contrast, five other non-antidepressants (acetaminophen, chlordiazepoxide, procainamide, quinidine, and theophylline) showed only minimal binding to cholestyramine under these conditions. Activated charcoal completely bound all drugs studied. These findings suggest that cholestyramine should be used with caution in patients receiving tricyclic antidepressants. They also suggest that cholestyramine may be a potentially useful adjunctive therapy in treatment of overdose with the tricyclic antidepressants.

Adsorption↗
PubMed1992

Immunoglobulin A (IgA) and IgG serum antibodies to mycobacterial antigens in Crohn's disease patients and their relatives.

Sera from patients with Crohn's disease, their relatives, their spouses, and unrelated healthy controls were assayed by enzyme-linked immunosorbent assay for immunoglobulin G (IgG) and IgA antibodies to Mycobacterium tuberculosis, M. avium, and M. gordonae. The patients had significantly higher IgA responses to mycobacterial antigens than did either their relatives or the controls. On the other hand, both the patients and their relatives had significantly higher IgG responses against these antigens than did the controls. The elevated IgA response was more pronounced against isopentanol-extracted whole bacterial cells than it was against soluble protein extracts, and it appeared to be directed against fixed surface antigens that lie under the loosely bound peptidoglycolipid or glycolipid antigens of mycobacteria.

Adult↗
PubMed1992

Medical record content: recurring area of concern in hospital analysis.

This article reports on an analysis of 109 hospitals that received recommendations for improvement within their Medical Record Service when surveyed by the Australian Council on Health Care Standards (ACHS) in 1990. Seventy-five per cent of Medical Record Service recommendations made at an earlier survey had been fully implemented and 17% partially implemented by hospitals at the time of their next survey in 1990. The major area receiving recommendations for improvement was medical record content. Other areas of concern were quality assurance, organization and administration, and space for research and work within the service. Certain aspects of medical record content also appeared to be resistant to change from one survey to the next.

Accreditation↗
PubMed1992

The significance of peritoneal cytology in stage IB cervical cancer.

OBJECTIVE: The purpose of this study was to determine the incidence of positive peritoneal cytology and to evaluate its usefulness in the management of patients with early-stage cervical cancer. METHODS: Peritoneal cytology was studied in 273 women undergoing primary surgical exploration for International Federation of Gynecology and Obstetrics stage IB cancer of the cervix. Charts were reviewed retrospectively for clinicopathologic data concerning tumor size, cell type, lymph node status, and outcome. RESULTS: Cytology was positive in four women, three of whom had enlarged pelvic or para-aortic lymph nodes or intraperitoneal disease. There was no association between tumor histology or tumor size and peritoneal cytology. CONCLUSION: The incidence of positive peritoneal cytology in early-stage cervical cancer is low, and the prognostic significance of positive cytology is overshadowed by other risk factors more obvious at surgery. The routine collection of cytologic specimens at laparotomy should be abandoned in this setting.

Female↗
PubMed1991

An appraisal of polystyrene-(ELISA) and nitrocellulose-based (ELIFA) enzyme immunoassay systems using monoclonal antibodies reactive toward antigenically distinct forms of human C-reactive protein.

The purpose of this study was to compare and contrast two enzyme immunoassay systems: the enzyme-linked immunosorbent assay (ELISA), which utilizes polystyrene microtiter plates as the adsorptive surface and the enzyme-linked immunoflow assay (ELIFA), which utilizes nitrocellulose membranes. The principal parameter under scrutiny was the denaturing or unfolding effects caused by the interaction of the protein with the adsorptive surfaces in each assay system. These effects were monitored by utilizing two conformationally distinct forms of human C-reactive protein (CRP), the native form of CRP and a denatured form (M-CRP), with a corresponding panel of monoclonal antibodies (MAbs) specific to either CRP or M-CRP. The results show that the ELIFA system was less sensitive than the ELISA system but that the ELIFA assay can be completed in less time than the ELISA. Also, adsorption of native CRP to the polystyrene surface in the ELISA system resulted in conformational changes of the adsorbed native CRP protein such that M-CRP reactive determinants were available for binding with anti-M-CRP MAbs, whereas native CRP adsorbed to the nitrocellulose membrane in the ELIFA system resulted in very limited conversion of CRP to M-CRP reactive epitopes. These results have important implications for development of immunoassays and screening of MAbs for proteins whose conformations may be affected by adsorption to various surfaces.

Antibodies, Monoclonal↗
PubMed1991

Plasma renin activity in renal transplant patients with hypertension.

Chronic renal allograft rejection (CR) is the major cause of graft loss after 1 year following transplantation. Hypertension (HTN) and proteinuria (Up) are the hallmarks of this immunologic allograft response. Over 1 year, 23 patients posttransplantation and with HTN (diastolic greater than 95 mm Hg) were examined. Serial serum creatinine (Scr), Up, urine creatinine (Ucr), and resting and enalapril challenged (EC) plasma renin activity (PRA) were all determined. Renal artery stenosis was excluded by noninvasive imaging. Of the 23 patients, eight eventually lost their renal allografts, while 15 maintained satisfactory renal function (Scr less than 2.5). Results of this study show that: 1) worsening renal function (RF) increases EC reactivity; 2) the presence of proteinuria is not itself related to increase in EC activity; 3) renin before and after EC was higher (P = .06) in the allograft loss group. In this study, patients with high PRA represent the highest EC responses. Therefore, they display not macrovascular lesions, but microvascular intrarenal disease; this defect is most likely secondary to chronic immunologic insult.

Adult↗
PubMed1991

The spectrum of spontaneous mutations in a Saccharomyces cerevisiae uracil-DNA-glycosylase mutant limits the function of this enzyme to cytosine deamination repair.

Uracil-DNA-glycosylase has been proposed to function as the first enzyme in strand-directed mismatch repair in eukaryotic organisms, through removal of uracil from dUMP residues periodically inserted into the DNA during DNA replication (Aprelikova, O. N., V. M. Golubovskaya, T. A. Kusmin, and N. V. Tomilin, Mutat. Res. 213:135-140, 1989). This hypothesis was investigated with Saccharomyces cerevisiae. Mutation frequencies and spectra were determined for an ung1 deletion strain in the target SUP4-o tRNA gene by using a forward selection scheme. Mutation frequencies in the SUP4-o gene increased about 20-fold relative to an isogenic wild-type S. cerevisiae strain, and the mutator effect was completely suppressed in the ung1 deletion strain carrying the wild-type UNG1 gene on a multicopy plasmid. Sixty-nine independently derived mutations in the SUP4-o gene were sequenced. All but five of these were due to GC----AT transitions. From this analysis, we conclude that the mutator phenotype of the ung1 deletion strain is the result of a failure to repair spontaneous cytosine deamination events occurring frequently in S. cerevisiae and that the UNG1 gene is not required for strand-specific mismatch repair in S. cerevisiae.

Base Sequence↗
PubMed1991

Reproductive behaviour of families segregating for Cooley's anaemia before and after the availability of prenatal diagnosis.

The reproductive behaviour of couples with heterozygous beta thalassaemia, with at least one affected child, was investigated for the period 1955 to 1984 and was compared to the behaviour of control couples matched for age, age at marriage, and presence of at least one child. The comparisons were made as a function of knowledge of the risk and availability of prenatal diagnosis and abortion. It was found that the couples segregating for Cooley's anaemia, before knowledge of the risk, had a higher reproductive rate than that of control couples. Knowledge of the genetic risk had a different effect on reproductive behaviour in the 1950s from that in later years. The difference was attributed both to the influence of cultural factors and to technical, therapeutic, and diagnostic advances.

Abortion, Eugenic↗