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Biomedical subjects

L Krueger

Publications and source records attributed to L Krueger.

14 recordsLinked to original sources
PubMed1998

Supernatant from stored red cells activates neutrophils.

Bioreactive substances including cytokines and lipids accumulate during storage of red blood cells (RBCs) but their clinical importance is uncertain. The goal of this study was to evaluate the effect of stored RBC supernatant on neutrophil activity in vitro. Packed RBCs (PRBCs) were collected and divided into two aliguots, one leukodepleted and the other nonleukodepleted. Plasma supernatant from PRBCs were collected on days 1, 8, 15, 29 and 35 and its effect on neutrophil expression of CD11b, CD16 and oxidative burst was measured by flow cytometry. Levels of tumour necrosis factor alpha (TNF alpha) and interleukin-8 (IL8) were also measured. The supernatant from PRBC units stored for greater than 15 days activated and primed neutrophils as evidenced by an increase CD11b and CD16 expression and oxidative burst. The greatest effect was seen in the oldest concentrates (35-day-old) (P < 0.008). Leukodepletion abrogated the effects of stored supernatant on CD11b and CD16 expression (P < 0.02) but did not reduce priming of the neutrophil oxidative burst (P > 0.1). Very low levels of IL8 and TNF alpha were detected in stored supernatants. Stored PRBC supernatant contains substances which directly enhance neutrophil expression of adhesion protein CD11b, CD16 and prime neutrophil oxidative burst. The exceedingly low level of IL8 and TNF alpha found in this study suggests that other factors may play a more important role in neutrophil priming and activation.

Biomarkers↗
PubMed1997

Comparison of immunologic amplification vs enzymatic deposition of fluorochrome-conjugated tyramide as detection systems for FISH.

Using various sizes and dilutions of hapten-conjugated DNA probes, we compared catalyzed reporter deposition (CARD) to fluorochrome-conjugated antibody layering (immunological method) for amplifying FISH signals. Cosmid and phage probes that contained human DNA inserts of 40 KB and 15 KB, respectively, and were mapped to chromosome 15q11.2 were used to evaluate these amplification methods. The probes were used either at standard concentrations (10 ng/microliter) or at dilutions up to 1:40 (0.25 ng/microliter). Detection of FISH signals using either immunological (three antibody layers) or CARD methods were comparable when the undiluted (10 ng/microliter) or 1:4 dilution (2.5 ng/microliter) of the cosmid probe was used. Use of a single fluorochrome-conjugated antibody layer produced very weak FISH signals. However, addition of an unlabeled secondary antibody followed by a third antibody conjugated to the same fluorochrome (i.e., two rounds of amplification) produced a strong signal that was detected at a 1:4 probe dilution but was not successfully detected at probe dilutions of 1:10 or greater. In contrast, intense probe signals were produced with the CARD method at all probe dilutions, particularly when coupled to extended hapten-antibody incubation times. The 15-KB phage probe was difficult to detect at a 1:4 dilution with the standard immunologic amplification methods but was readily detected with the CARD method. These data suggest that CARD may be useful for FISH in that (a) less probe may be needed and therefore valuable probe reagents may be conserved, and (b) smaller targets may be detected, thus extending the range of this technique.

Chromosomes, Human, Pair 15↗
PubMed1996

Elevated levels of recombinational DNA repair in human somatic cells expressing the Saccharomyces cerevisiae RAD52 gene.

The Saccharomyces cerevisiae RAD52 gene was introduced into the human fibrosarcoma-derived cell line HT1080. Transfected cell lines that expressed the yeast transgene catalyzed inter-plasmid homologous DNA recombination at frequencies approx. 12-fold higher than did control cells. Additional experiments revealed that yeast RAD52 gene expression increased the level of resistance to the DNA damaging agents diepoxybutane, and methyl methanesulfonate, but did not alter sensitivity to ultraviolet radiation. These results indicate that the S. cerevisiae Rad52 protein can function in a human somatic cell background and provide support for the idea that a homologous recombination-based DNA repair process functions in mammalian somatic cells.

Anti-Bacterial Agents↗
PubMed1992

Association of human immunodeficiency virus and anal human papillomavirus infection among homosexual men.

BACKGROUND: A previous study of men with proctitis, proctocolitis, or enteritis showed an association of anal human papillomavirus (HPV) infection with human immunodeficiency virus (HIV) infection. Because anorectal abnormalities may confound an observed association between anal HPV DNA and HIV seropositivity, the present study was undertaken among consecutive homosexual men seeking HIV serologic testing who were unselected for anorectal symptoms. METHODS: Consecutive homosexual men underwent a standardized interview, physical examination, and collection of specimens for HIV serologic testing and detection of anal HPV DNA. RESULTS: Anal HPV DNA was detected in eight (31%) of 26 HIV-seropositive men and in 10 (8%) of 119 HIV-seronegative men (odds ratio, 5.8; 95% confidence interval, 1.1 to 30.1, adjusted for history of sexually transmitted disease, current anorectal symptoms, and age). When men with anorectal symptoms were excluded from the analysis, anal HPV DNA was detected in 27% of seropositive men compared with 8% of seronegative men (odds ratio, 4.4; 95% confidence interval, 1.4 to 13.4). There was no difference between HIV-seropositive and HIV-seronegative men with respect to distribution of type of HPV DNA. Men with group II or III and group IV HIV disease were 4.1 and 10.9 times, respectively, more likely than HIV-seronegative men to have anal HPV DNA detected. CONCLUSIONS: Because HIV-seropositive men appear to be at increased risk for the detection of anal HPV DNA, the natural course of anal HPV infection should be compared among HIV-seropositive and HIV-seronegative homosexual men.

Anus Diseases↗
PubMed1991

Mothers' and sons' cognitive and emotional reactions to stimulated marital and family conflict.

This study examined cognitive and emotional reactions to family discussions as experienced by sons and mothers from homes with physically aggressive (PA), verbally aggressive (VA), and low-conflict (LC) marital relationships. Boys of PA couples demonstrated more self-interference, self-distraction, and arousal and less criticism than did other sons in reaction to stimulated parental conflict. Boys of LC parents were more optimistic about family conflict and articulated more ideas concerning family structure and how conflict "should" proceed than did other sons. PA mothers made more positive evaluations and offered more autocratic suggestions than did VA mothers. Also, LC mothers, compared with both conflictual groups, made more democratic statements in response to low-conflict situations. These results indicate that marital conflict experienced in the home may influence sons' and mothers' appraisals of family and marital interactions.

Adaptation, Psychological↗
PubMed1988

Use of a preferred provider by employees of the preferred provider.

Little is known about the use of services in a preferred provider organization. We studied Pacific Medical Center (PMC) in Seattle which offered a preferred provider arrangement to its employees who selected a Blue Cross-Blue Shield type of plan. PMC offered to waive copayments and reduce deductibles for those employees when they (or their dependents) used PMC. PMC was thus a preferred provider. In the first 16 months of this program, 632 subjects made at least one claim; of these, 444 (70 percent) used the preferred provider at least once. The use of PMC was highest for male employees (84 percent had at least one visit), next for female employees (74 percent), and lowest for dependents (58 percent). Approximately one-third (32 percent) used PMC exclusively, 30 percent used other providers exclusively, and 37 percent used a combination of PMC and other providers. These may be thought of as best-case estimates, since the subjects--particularly the male employees--had a high level of familiarity with the program and ease of access, while the dependents had high familiarity but less convenient access. Female employees may have used PMC less because of relationships already established with other physicians. Outpatient and inpatient charges were more than twice as high for those who used both PMC and other providers as for those who used one provider exclusively. It may be that the preferred provider arrangement encourages higher charges or, alternatively, that it provides additional flexibility for those who have the most need for care.

Adolescent↗
PubMed1987

Use of ambulatory health care services in a preferred provider organization.

The organization of the delivery of health care can have significant cost-saving implications, but few of the available studies have made adequate comparisons of costs across plans. Furthermore, new organizational types such as independent practice associations and preferred provider organizations have not yet been studied in detail. This paper examines ambulatory utilization in a preferred provider organization (PPO) for Uniformed Services beneficiaries at Pacific Medical Center (PMC) in Seattle. The utilization in the PPO is compared with the results of a recently reported study of three other organizationally different Seattle plans: a Blue Cross/Blue Shield plan (BC), a closed-panel health maintenance organization (HMO), and an independent practice association (IPA). The PPO was similar to the IPA and the HMO in having a high percent of patients with any ambulatory use and had standardized ambulatory costs per user which were lower than BC but higher than the HMO. Thus, this particular type of PPO may have cost-saving features, particularly because the Uniformed Services population is known to use more health services than the general population. Methodological issues for future utilization research across organizations are also discussed.

Adolescent↗
PubMed1984

Prediction of pneumonia in outpatients with acute cough--a statistical approach.

Cough is the fifth most common reason for physician visits, but data on acute cough have rarely been collected in a standardized manner and have not been analyzed in a multivariate fashion. We report data on 1819 patients presenting with cough, all of whom received a standardized history and physical, and a chest X-ray. Only 48 (2.6%) were found to have an acute radiographic infiltrate (pneumonia). The prevalence of common signs and symptoms is shown for the patients with and without pneumonia. Thirty-two of these findings were significant predictors of pneumonia (p less than 0.05, one-tailed). These 32 did not include some of the expected predictors of pneumonia and did include some predictors not previously described in the literature. A diagnostic rule is developed which identifies pneumonia patients with 91% sensitivity and 40% specificity, or 74% sensitivity and 70% specificity. The study results suggest that many pneumonias could be predicted based only on the patients histories. Physician visits to determine physical findings and chest X-rays might be avoided by telephone triage, with substantial cost savings.

Acute Disease↗
PubMed1983

Early effects of high-dosed absorbable amoscanate on rat brain.

An oily suspension of the absorbable form of amoscanate was administered to young adult albino rats in single or repeated oral doses of 25, 125 and 500 mg/kg. At least 3 consecutive doses of 125 or 500 mg/kg were needed to induce a brain lesion. The early change consisted of necrosis of the ependyma of the lateral ventricles, indicating that intoxication may have occurred via the cerebrospinal fluid.

Aniline Compounds↗
PubMed1978

Cellular and molecular studies on globin gene expression.

Globin gene expression has been studied with the use of a combination of cell and molecular biology techniques. With a somatic cell hybrid between mouse erythroleukemia (MEL) and human erythroid cells, human and mouse globin genes can be coexpressed in the same hybrid cell. Somatic cell hybridization between MEL cells and nonerythroid cells (e.g., human fibroblasts) results in hybrid cells that cannot be induced to produce hemoglobin of any type. Molecular hybridization of cellular DNA and RNA with globin cDNA indicates that the globin genes are present but that no globin mRNA is in the nonexpressing hybrid cell. This finding demonstrates that the loss of globin gene expression in the hybrid cell occurs at the level of transcription or mRNA processing. The nucleus of the nonerythroid cell is not necessary for the extinction of globin gene expression, since cybrids formed from MEL cells with enucleated nonerythroid cells also result in cells which cannot be induced to synthesize hemoglobin even after 40 or more generations. These data suggest that the cytoplasm of cells contains diffusible regulatory molecules which influence globin gene expression. In our attempt to develop an intracellular assay to test for regulatory molecules, we studied the procedure microinjection with red blood cell (RBC) ghosts. Rabbit globin mRNA (with hemin) was loaded into RBC's and then, by Sendai virus-mediated fusion, into Chinese hamster ovary (CHO) cells growing in culture; these microinjected CHO cells synthesized hemoglobin. Since this microinjection procedure appears to be effective in inserting both proteins and nucleic acids into intact cells, it should be possible to develop modifications for inserting aliquots of fractionated cytoplasm into growing cells. The procedure might then be useful as an assay for putative genetic regulatory molecules.

Animals↗
PubMedDate not supplied

Prediction of fracture in patients with acute musculoskeletal ankle trauma.

X-rays taken for ankle trauma contribute significantly to the cost of health care in this country. In an attempt to find clinical correlates of ankle fracture 36 detailed historical and physical examination variables were collected from 587 consecutive patients with ankle trauma, and ankle x-rays were taken of all patients. The association of each variable with the final diagnosis of fracture, rupture, or sprain was tested; 21 variables were significant predictors of fracture (vs. sprain and rupture) and 15 were not significantly associated with final diagnosis. The variables were used in a linear discriminant analysis to develop a rule which would predict the final diagnosis. If only those patients predicted by the rule to have fractures had been x-rayed, all patients with fracture would have been identified but more than a fourth of all ankle trauma patients would have been spared x-rays. This compares favorably with a recently published rule that did not assess sensitivity. A simulated prospective evaluation suggests that these results are stable, but that up to 10% of the fractures could be missed on the first visit. Although current practice is not well documented, it appears that use of this rule could yield substantial cost savings.

Adolescent↗
PubMedDate not supplied

Chromosome rearrangements in fumigant appliers: possible relationship to non-Hodgkin's lymphoma risk.

Appliers of pesticides (n = 18) who are exposed to the fumigant phosphine or who have a mixed exposure to other pesticides and phosphine demonstrate a significant increase in chromosome rearrangements in G-banded chromosomes from peripheral blood compared to control subjects (n = 26). Appliers who had discontinued using phosphine for at least 8 months prior to specimen collection (n = 5) do not demonstrate significant increases in chromosome rearrangements compared to controls. Breakpoint analysis of 6,138 metaphases from all subjects demonstrates 196 breaks per 3605 metaphases in exposed subjects and 102 breaks per 2,533 metaphases in control subjects. Bands with significantly more breaks than expected based on band length in all study subjects were 1q32, 3p14, 7p15, and 14q11. Three of these four bands had significantly more breaks than expected in the exposed group, and all four bands had a significant excess of breaks in the control group. There are four bands with a significant excess of breaks in the exposed group and no breaks in the control group; each of these occurs in a known protooncogene region. These are 1p13 (NRAS), 2p23 (NMYC), 14q32 (ELK2), and 21q12 (ETS-2). Most breaks at bands 1p13, 14q32, and 21q22 are associated with chromosome rearrangements and occurred in appliers who have a mixed exposure to phosphine and other pesticides. Cytogenetic abnormalities, i.e., rearrangements and/or deletions involving bands 1p13, 2p23, and 14q32, are associated with non-Hodgkin's lymphoma. We speculate that these findings could relate to the risk of evolution of a neoplastic clone in these workers. Epidemiological studies of similarly exposed workers indicate an excess of non-Hodgkin's lymphoma.

Chromatids↗
PubMedDate not supplied

Continuing unsafe sex: assessing the need for AIDS prevention counseling.

To assess the need for acquired immunodeficiency syndrome (AIDS) prevention counseling for gay and bisexual men who were continuing to engage in unsafe sex, a nonprobability telephone survey--the data may not be generalizable to the population--was conducted in Seattle during March 1987. In a 4-week period, 141 callers phoned in response to local publicity and completed a 30-minute anonymous interview. This paper focuses on 106 male respondents who were behaviorally defined as gay (that is, sex during the past year exclusively with partners of the same sex, N = 74) or bisexual (sex with both men and women, N = 32). The modal respondent was a never-married white male in his thirties who had some college education and was employed full-time in a white collar occupation. The gay men were more likely than the bisexual men to report that their family members and friends knew of their sexual orientation and to indicate that they were able to discuss their concerns about unsafe sex with someone close to them. Gay men were also more likely to use condoms and to have engaged in anonymous sex during the 3 months before the interview. More gay men had engaged in unprotected receptive anal intercourse (27 percent) than had bisexual men (13 percent), and in considerably more insertive anal intercourse (42 percent versus 22 percent). Of the gay men interviewed, 73 percent indicated that they needed help in changing their high-risk sexual behaviors compared with 61 percent of bisexuals. However, respondent preferences for the context of counseling (for example, sexual preference of the counselor,group versus individual counseling, type of agency) differed on the basis of the respondent's self definition of sexual preference. Bisexual men expressed a preference for individual therapy delivered by a private practitioner who is a heterosexual. The authors conclude that men who are at risk of AIDS due to ongoing unsafe sex will require a diversity of counseling options.

Acquired Immunodeficiency Syndrome↗