Detection of enterotoxigenic Escherichia coli in foods by polymerase chain reaction

Enterotoxigenic Escherichia coli (ETEC) causes significant morbidity and mortality in infants of developing countries and is the most common cause of diarrhea in travelers to these areas. Enterotoxigenic Escherichia coli infections are commonly caused by ingestion of fecally contaminated food. A timely method for the detection of ETEC in foods would be important in the prevention of this disease. A multiplex polymerase chain reaction (PCR) assay which has been successful in detecting the heat-labile and heat-stable toxins of ETEC in stool was examined to determine its utility in foods. This PCR assay, preceded by a glass matrix and chaotropic DNA extraction, was effective in detecting high numbers of ETEC in a variety of foods. Ninety percent of 121 spiked food samples yielded positive results. Samples of salsa from Guadalajara, Mexico and Houston, Texas were collected and underwent DNA extraction and PCR. All samples yielded negative results for both the heat-labile and heat-stable toxins. Samples were also subjected to oligonucleotide probe analysis and resulted in 5 samples positive for ETEC. Upon dilution testing, it was found that positive PCR results only occurred when 12,000 to 1,000,000 bacteria were present in 200 mg of food. Although the DNA extraction and PCR method has been shown to be both sensitive and specific in stool, similar results were not obtained in food samples. ^

Immunology and HIV expression in skin, in vitro, and in response to ultraviolet light

HIV can enter the body through Langerhans cells, dendritic cells, and macrophages in skin mucosa, and spreads by lysis or by syncytia. Since UVL induces of HIV-LTR in transgenic mice mid in cell lines in vitro, we hypothesized that UVB may affect HIV in people and may affect HIV in T cells in relation to dose, apoptosis, and cytokine expression. To determine whether HIV is induced by UVL in humans, a clinical study of HIV+ patients with psoriasis or pruritus was conducted during six weeks of UVB phototherapy, Controls were HIV-psoriasis patients receiving UVB and HIV+ KS subjects without UVB.Blood and skin biopsy specimens were collected at baseline, weeks 2 and 6, and 4 weeks after UVL. AIDS-related skin diseases showed unique cytokine profiles in skin and serum at baseline. In patients and controls on phototherapy, we observed the following: (1) CD4+ and CD8+ T cell numbers are not significantly altered during phototherapy, (2) p24 antigen levels, and also HIV plasma levels increase in patients not on antiviral therapy, (3) HIV-RNA levels in serum or plasma. (viral load) can either increase or decrease depending on the patient's initial viral load, presence of antivirals, and skin type, (4) HIV-RNA levels in the periphery are inversely correlated to serum IL-10 and (5) HIV+ cell in skin increase after UVL at 2 weeks by RT-PCR in situ hybridization mid we negatively correlated with peripheral load. To understand the mechanisms of UVB mediated HIV transcription, we treated Jurkat T cell lines stably transfected with an HIV-LTR-luciferase plasmid only or additionally with tat-SV-40 early promoter with UVB (2 J/m2 to 200 J/m2), 50 to 200 ng/ml rhIL-10, and 10 μg/ml PHA as control. HIV promoter activity was measured by luciferase normalized to protein. Time points up to 72 hours were analyzed for HIV-LTR activation. HIV-LTR activation had the following properties: (1) requires the presence of Tat, (2) occurs at 24 hours, and (3) is UVB dose dependent. Changes in viability by MTS (3-(4,5-dimethyhhiazol-2-y1)-5-(3-carboxymethoxyphonyl)-2-(4-sulfophenyl)-2H-tetrazolium) mixed with PMS (phenazine methosulfate) solution and apoptosis by propidium iodide and annexin V using flow cytometry (FC) were seen in irradiated Jurkat cells. We determined that (1) rhIL-10 moderately decreased HIV-LTR activation if given before radiation and greatly decreases it when given after UVB, (2) HIV-LTR activation was low at doses of greater than 70 J/m2, compared to activation at 50 J/m2. (Abstract shortened by UMI.)^

Transcriptional regulation of the human Fas (CD95) promoter

The coordination of the apoptotic program necessitates the timely expression of sensor, effector, and mediator molecules. Fas/CD95, a transmembrane receptor which tethers the cell-death machinery, triggers apoptosis to maintain immune homeostasis, tolerance, and surveillance. Dysregulation in Fas-mediated apoptosis, either from disproportionate expression or disruptions in the downstream signaling pathway, manifests in autoimmune disorders and certain malignant progression. ^ In this project, the transcriptional requirements underlying two modulators of Fas expression were investigated. In T-lymphocytes, activation results in potent Fas upregulation followed by an acquisition of sensitivity towards FasL-mediated apoptosis. Human fas promoter cloning and analysis have identified a cis-element critical for inducible Fas expression. EMSA studies using this region demonstrated a constitutive association with the transcription factor Sp1 and inducible NF-κB binding in response to activation. These interactions were mutually exclusive, as the rB/Sp1 element bound with recombinant Sp1 was readily displaced by increasing amounts of NF-κB p50. Thus, Fas upregulation by T-cell activation stimuli is dependent upon NF-κB binding at the fas promoter. ^ The capacity of Sp1 to direct basal Fas expression was examined through mutagenesis of several GC-rich regions within the core fas promoter. Reporter analysis of single or combinatorial mutant GC-box constructs revealed usage of a particular GC-element in moderating over 50% of basal fas transcription. Inducible expression was Sp1-independent, however, since activated Jurkat cells containing fas Sp1-mutant constructs retained equivalent reporter induction. Overall, a dual-level of transcriptional control exists in fas, where constitutive activity is monitored through Sp1 binding, whereas T-cell activation obligates NF κB transactivation. ^ In response to genotoxic damage, p53 modulates Fas levels partly by a transcription-dependent mechanism. Reconstitution of wild-type p53 in the hepatoma cell line Hep3B readily induced Fas transcription. Furthermore, fas promoter analysis identified an undescribed p53 responsive element which, when deleted, ablated p53-mediated reporter activity. Therefore, the pro-apoptotic function mediated by p53 is driven partially through the enhancement of Fas expression. ^ Altogether, events elicting Fas transcription may invoke single or overlapping mechanisms that converge at the level of promoter activity. Agents that enhance or attenuate these pathways may be therapeutically beneficial in modulating the expression and sensitivity towards Fas-dependent apoptosis. ^

A case-control study of bilateral compared with unilateral breast cancer

Approximately 10 to 15% of breast cancer patients develop a primary cancer in the contralateral breast. This study examined differences between women with unilateral compared with bilateral primary breast cancer. It focused on hormonal factors and family history, and evaluated the prevalences of invasive lobular histology and the replication error phenotype in the tumors. ^ Cases (n = 82) were patients at M.D. Anderson Cancer Center (MDACC) in Houston, Texas diagnosed with primary breast cancer in each breast between 1985 and 1994 inclusive. Controls (n = 82) were MDACC patients with primary cancer in a single breast diagnosed during the same interval, individually matched to cases. Data were obtained by in-person and/or telephone interview with the patient and/or proxy. Replication error phenotype was determined from archival tissue. ^ Diagnosis of breast, but not ovarian, cancer in a female first-degree relative (FFDR) was a strong risk factor for bilateral cancers. Cases had a significantly 3-fold higher excess of familial breast cancer than did controls (cases: O/E = 2.65, 95% CI = 1.85–3.69; controls: 0.86, 0.46–1.47; homogeneity: p = 0.00). Risk did not vary with menopausal status of the patient, but was greatest if a relative was diagnosed before age 45 (O/E = 38.9; 95% CI = 21.7–64.1). By implication, young first-degree relatives of patients with bilateral breast cancer are at very high risk of breast cancer themselves. Cases also had significantly fewer siblings than did controls. ^ Earlier menarche, and parity in the absence of lactation, were associated with bilateral cancers; age at menopause and parity with lactation were not. A history of alcohol consumption, particularly if heavy, carried a 3.4-fold risk (p = 0.03). The data suggested a slightly different pattern in risk factors according to menopausal status and interval between cancers. ^ Replication error phenotype was available for 59 probands. It was associated with bilateral cancers (particularly if diagnosed within one year of each other), increased age (p = 0.02) and negative nodal status. Invasive lobular histology was associated with bilateral disease but numbers were small. ^ These data suggest bilateral breast cancer arises in the context of a combination of familial and hormonal factors, and alcohol consumption. The relative importance of each factor may vary by age of the patient. ^

A novel form of CYP3A from rat brain: cDNA cloning, protein characterization and gene regulation of cytochrome P450 3A9

One full length cDNA clone, designated 3aH15, was isolated from a rat brain cDNA library using a fragment of CYP3A2 cDNA as a probe. 3aH15 encoded a protein composed of 503 amino acid residues. The deduced amino acid sequence of 3aH15 was 92% identical to mouse Cyp3a-13 and had a 68.4% to 76.5% homology with the other reported rat CYP3A sequences. Clone 3aH15 was thus named CYP3A9 by Cytochrome P450 Nomenclature Committee. CYP3A9 seems to the major CYP3A isozyme expressed in rat brain. Sexual dimorphism of the expression of CYP3A9 was shown for the first time in rat brain as well as in rat liver. CYP3A9 appears to be female specific in rat liver based on the standards proposed by Kato and Yamazoe who defined sex specific expression of P450s as being a 10-fold or higher expression level in one sex compared with the other. CYP3A9 gene expression was inducible by estrogen treatment both in male and in female rats. Male rats treated with estrogen had a similar expression level of CYP3A9 mRNA both in the liver and brain. Ovariectomy of adult female rats drastically reduced the mRNA level of CYP3A9 which could be fully restored by estrogen replacement. On the other hand, only a two-fold induction of CYP3A9 expression by dexamethasone was observed in male liver and no significant induction of CYP3A9 mRNA was observed in female liver or in the brains. These results suggest that estrogen may play an important role in the female specific expression of the CYP3A9 gene and that CYP3A9 gene expression is regulated differently from other CYP3A isozymes. ^ P450 3A9 recombinant protein was expressed in E. coli using the pCWOri+ expression vector and the MALLLAVF amino terminal sequence modification. This construct gave a high level of expression (130 nmol P450 3A9/liter culture) and the recombinant protein of the modified P450 3A9 was purified to electrophoretic homogeneity (10.1 nmol P450/mg protein) from solubilized fractions using two chromatographic steps. The purified P450 3A9 protein was active towards the metabolism of many clinically important drugs such as imipramine, erythromycin, benzphetamine, ethylmorphine, chlorzoxazone, cyclosporine, rapamycin, etc. in a reconstituted system containing lipid and rat NADPH-P450 reductase. Although P450 3A9 was active towards the catabolism of testosterone, androstenedione, dehydroepiandrosterone (DHEA) and 17β-estradiol, P450 3A9 preferentially catalyzes the metabolism of progesterone to form four different hydroxylated products. Optimal reconstitution conditions for P450 3A9 activities required a lipid mixture and GSH. The possible mechanisms of the stimulatory effects of GSH on P450 3A9 activities are discussed. Sexually dimorphic expression of P450 3A9 in the brain and its involvement in many neuroactive drugs as well as neurosteroids suggest the possible role of P450 3A9 in some mental disorders and brain functions. ^

Alcohol consumption and breast cancer risk among Hispanic and non-Hispanic women in New Mexico

Breast cancer incidence and mortality rates for Hispanic women are lower than for non-Hispanic white (NHW) women, but recently rates have increased more rapidly among Hispanic women. Many studies have shown a consistent increased breast cancer risk associated with modest or high alcohol intake, but few included Hispanic women. Alcohol consumption and risk of breast cancer was investigated in a New Mexico statewide population-based case-control study. The New Mexico Tumor Registry ascertained women, newly diagnosed with breast cancer (1992–1994) aged 30–74 years. Controls were identified by random digit dialing and were frequency-matched for ethnicity, age-group, and health planning district. In-person interviews of 712 cases and 844 controls were conducted. Data were collected for breast cancer risk factors, including alcohol intake. Recent alcohol intake data was collected for a four-week period, six months prior to interview. Past alcohol intake included information on alcohol consumption at ages 25, 35, and 50. History of alcohol consumption was reported by 81% of cases and 85% of controls. Of these women, 42% of cases and 48% of controls reported recent alcohol intake. Results for past alcohol intake did not show any trend with breast cancer risk, and were nonsignificant. Multivariate-adjusted odds ratios for recent alcohol intake and breast cancer suggested an increased risk at the highest level for both ethnic groups, but estimates were unstable and statistically nonsignificant. Low level of recent alcohol intake (<148 grams/week) was associated with a reduced risk for NHW women (Odds Ratio (OR) = 0.49 95% Confidence Interval (CI) 0.35–0.69). This pattern was independent of hormone-receptor status. The reduced breast cancer risk for low alcohol intake was present for premenopausal (OR = 0.29, 95% CI 0.15–0.56) and postmenopausal NHW women (OR = 0.56, 95% CI 0.35–0.90). The possibility of an increased risk associated with high alcohol intake could not be adequately addressed, because there were few drinkers with more than light to moderate intake, especially among Hispanic women. An alcohol-estrogen link is hypothesized to be the mechanism responsible for increased breast cancer risk, but has not been consistently substantiated. More studies are needed of the underlying mechanism for an association between alcohol intake and breast cancer. ^

Neural tube defects in Mexican-Americans living on the US-Mexico border: The effects of folic acid and dietary folate

Neural tube defects (NTDs) are malformations of the developing brain and spinal cord; the most common are anencephaly and spina bifida. Evidence from many populations suggests that 50% of NTDs can be prevented through daily consumption of folic acid. A recent study has reported that folic acid may not protect populations of Mexican descent. This finding has serious implications for women living along the US-Mexico border. Not only is risk high in these Mexican American women compared with other US women; they also differ markedly in supplemental folic acid and dietary folate consumption, and in NTD-related risks (e.g., obesity, diabetes). This case-control study investigated whether folic acid supplements and dietary folate reduces NTDs in Mexican Americans. Cases included liveborn, stillborn, electively and spontaneously aborted NTD-affected fetuses and infants occurring in the 14-county Texas-Mexico border. Controls were randomly selected from unaffected live births, frequency matched to cases by hospital and year. An in-person interview of 110 case and 113 control mothers solicited data on folic acid supplements, dietary folate, and other covariates. Consumption of folic acid-containing vitamins before conception was only 5% for both case and control women. Taking vitamins the trimester before conception had no apparent effect, after adjusting for covariates [odds ratio (OR) = 1.0, 95% confidence interval (CI) = 0.3–3.4]. Combining folate from vitamins and diet showed a 20% risk reduction for women consuming at least 400 μg of folate daily [OR = 0.8, 95% CI = 0.5–1.5]; however, this estimate is statistically indistinguishable from the null. Although consistent with an inherent ineffectiveness of supplemental folic acid, that so few women consumed multivitamins during the critical time severely limited the assessment of folic acid in this population. A reduced folate response in Mexican descent women may be due to a genetic heterogeneity for metabolizing folate. Alternatively, folate intakes may be insufficient to overcome other underlying risk factors. In conclusion, determining whether folic acid reduces NTD risk in Mexican American women requires further study in populations with higher folic acid exposures. Meanwhile, we should pursue all recommended prevention strategies to reduce risk, including motivating Mexican American women of childbearing age to take folic acid routinely. ^

Effect of nonnormal random components on level and power in group-randomized trials

The use of group-randomized trials is particularly widespread in the evaluation of health care, educational, and screening strategies. Group-randomized trials represent a subset of a larger class of designs often labeled nested, hierarchical, or multilevel and are characterized by the randomization of intact social units or groups, rather than individuals. The application of random effects models to group-randomized trials requires the specification of fixed and random components of the model. The underlying assumption is usually that these random components are normally distributed. This research is intended to determine if the Type I error rate and power are affected when the assumption of normality for the random component representing the group effect is violated. ^ In this study, simulated data are used to examine the Type I error rate, power, bias and mean squared error of the estimates of the fixed effect and the observed intraclass correlation coefficient (ICC) when the random component representing the group effect possess distributions with non-normal characteristics, such as heavy tails or severe skewness. The simulated data are generated with various characteristics (e.g. number of schools per condition, number of students per school, and several within school ICCs) observed in most small, school-based, group-randomized trials. The analysis is carried out using SAS PROC MIXED, Version 6.12, with random effects specified in a random statement and restricted maximum likelihood (REML) estimation specified. The results from the non-normally distributed data are compared to the results obtained from the analysis of data with similar design characteristics but normally distributed random effects. ^ The results suggest that the violation of the normality assumption for the group component by a skewed or heavy-tailed distribution does not appear to influence the estimation of the fixed effect, Type I error, and power. Negative biases were detected when estimating the sample ICC and dramatically increased in magnitude as the true ICC increased. These biases were not as pronounced when the true ICC was within the range observed in most group-randomized trials (i.e. 0.00 to 0.05). The normally distributed group effect also resulted in bias ICC estimates when the true ICC was greater than 0.05. However, this may be a result of higher correlation within the data. ^

Integrin signaling in the regulation of lymphocyte morphology

In normal lymphocytes an “inside-out” signal up-regulating integrin adhesion is followed by a ligand mediated “outside-in” signal for cell spreading. Although PKC mediates both events, distinct roles were found for different PLCs. The inhibition of phosphatidylinositol specific PLC decreased both cell adhesion and spreading on fibronectin in T cell receptor/CD28 activated peripheral blood T cells. However, inhibition of phosphatidylcholine specific PLC only blocked cell spreading and did not affect adhesion, indicating that “inside-out” signaling for the integrin α4β1 proceeds through phosphatidylinositol specific PLC and PKC, while the “outside-in” signal utilizes phosphatidylcholine specific PLC and PKC. Furthermore, β1 integrin chain mediated morphological changes in the T lymphocytic cell line HPB-ALL directly paralleled PKA activation, treatment of these cells with an inhibitory anti-β1 antibody blocked PKA activation and cell spreading, and this inhibition could be overcome by activating adenylate cyclase. Furthermore, inhibition of PKA was found to decrease the overall strength of cell adhesion or cellular avidity without affecting individual receptor affinity for soluble ligand. ^ When HPB-ALL cells interact with immobilized FN, two separate morphological phenotypes can be induced. Some cells flattened their cell body into a triangular shape and begin to migrate, while others extended a pseudopod from their stationary cell body. This second morphology recapitulates the shape changes observed during transendothelial migration. During these morphological changes, α4β1 integrins are internalized into endocytic vesicles that ultimately accumulate at the juncture between the cell body and an extending pseudopod. From this juncture, they are rapidly transported down the length of the pseudopod to its most distal end. ^ In addition to an accumulation of integrin containing vesicles, the pseudopod base was found to have increased amounts of the small GTPase RhoA and active PKA. The inhibition of PKA or RhoA resulted in lymphocytes with similar aberrant stellate morphologies. Furthermore, inhibition of PKA blocked the α4β1 mediated phosphorylation of RhoA. The co-localization of active PKA, RhoA and integrin containing endocytic vesicles indicates that integrin triggering can cause the rapid redistribution and activation of key signaling intermediates and raises the possibility that regulation of lymphocyte morphology by PKA and RhoA is through adhesion receptor recycling. ^

Developmental effects of estrogen and PCBs in the reproductive tract of BALB/C mice

Many of the tumorigenic effects that result from neonatal exposure to both natural and synthetic estrogens resemble those found in humans exposed to diethylstilbestrol (DES) in utero. Using this established DES neonatal mouse model, my goal was to investigate long-term molecular and morphological effects of certain polychlorinated biphenyls (PCBs) that are weakly estrogenic in adult mice. Focusing on the cervicovaginal (CV) tract, since this is where tumors develop in the BALB/c mouse, I first assessed the 17β-estradiol (E2) dose-response for expression of lactoferrin (LTF). LTF is a highly inducible estrogen biomarker that is permanently altered in uteri from neonatally treated mice. Treatments were administered via 5 subcutaneous injections beginning within 16 hrs after birth, days 1–5. ^ The ontogeny of LTF expression from mouse CV tracts was determined by examining three different stages of life: pups, immature, and mature mice. Northern RNA analysis and immunohistochemistry showed that neonatal E 2 treatment both increases and decreases LTF expression. Early expression of LTF in the CV tract at all doses occurred in pups. In both immature and adult mice, increased LTF expression was dependent on whether E2 induced ovary-dependent or ovary-independent persistent vaginal cornification. ^ Next, I studied biological responses from neonatally PCB exposed adult mice. As expected, using a neonatal uterine bioassay I showed that 2 ′4′6′-trichloro-4-biphenylol (OH-PCB-30), 2′3′4′ 5-tetrachloro-4-biphenyloI (OH-PCB-61), and OH-PCB-30/61 (50/50 mixture), were estrogenic causing a dose-dependent increase in uterine weight. ^ Long-term effects of OH-PCB 30 [200 μg/pup/day] were most similar to E2 as seen by an increased uterine wet weight in day 50 mice similar to E2 [5 μg/pup/day] (141% and 140% of control, respectively). Another similarity between OH-PCB 30 and E2 neonatally treated mice was found in those sacrificed at 20 months of age. At these same doses CV tract squamous cell carcinoma induction was 43% of E2 treated mice and 47% of OH-PCB 30 treated mice. Differences were noted in adenoaquamous; cell carcinoma development, where 16% of OH-PCB-30 neonatally treated mice developed tumors versus 8% for E2. Based on these results using the neonatal mouse model, I conclude that the OH-PCBs tested are strongly estrogenic and tumorigenic showing dose-response relationships when exposure occurs during development of the reproductive tract in mice. These results may have important implications for risk assessment in determining the effects of xenoestrogens exposure early versus later in life. ^

Cytochrome P450 2D18 in the mammalian brain: Recombinant expression, purification, and characterization of xenobiotic and endobiotic metabolism

The cytochromes P450 (P450) comprise a superfamily of hemoproteins that function in concert with NADPH-cytochrome P450 reductase (P450-reductase) to metabolize both endogenous and exogenous compounds. Many pharmacological agents undergo phase I metabolism by this P450 and P450-reductase monooxygenase system. Phase I metabolism ensures that these highly hydrophobic xenobiotics are made more hydrophilic, and hence easier to extrude from the body. While the majority of phase I metabolism occurs in the liver, metabolism in extrahepatic organ-systems like the intestine, kidney, and brain can have important roles in drug metabolism and/or efficacy. ^ While P450-mediated phase I metabolism has been well studied, investigators have only recently begun to elucidate what physiological roles P450 may have. One way to approach this question is to study P450s that are highly or specifically expressed in extrahepatic tissues. In this project I have studied the role of a recently cloned P450 family member, P450 2D18, that was previously shown to be expressed in the rat brain and kidney, but not in the liver. To this end, I have used the baculovirus expression system to over-express recombinant P450 2D18 and purified the functional enzyme using nickel and hydroxylapatite chromatography. SDS-PAGE analysis indicated that the enzyme was purified to electrophoretic homogeneity and Western analysis showed cross-reactivity with rabbit anti-human P450 2D6. Carbon monoxide difference spectra indicated that the purified protein contained no denatured P450 enzyme; this allowed for further characterization of the substrates and metabolites formed by P450 2D18-mediated metabolism. ^ Because P450 2D18 is expressed in brain, we characterized the activity toward several psychoactive drugs including the antidepressants imipramine and desipramine, and the anti-psychotic drugs chlorpromazine and haloperidol. P450 2D18 preferentially catalyzed the N-demethylation of imipramine, desipramine, and chlorpromazine. This is interesting given the fact that other P450 isoforms form multiple metabolites from such compounds. This limited metabolic profile might suggest that P450 2D18 has some unique function, or perhaps a role in endobiotic metabolism. ^ Further analysis of possible endogenous substrates for P450 2D18 led to the identification of dopamine and arachidonic acid as substrates. It was shown that P450 2D18 catalyzes the oxidation of dopamine to aminochrome, and that the enzyme binds dopamine with an apparent KS value of 678 μM, a value well within reported dopamine concentration in brain dopaminergic systems. Further, it was shown that P450 2D18 binds arachidonic acid with an apparent KS value of 148 μM, and catalyzes both the ω-hydroxylation and epoxygenation of arachidonic acid to metabolites that have been shown to have vasoactive properties in brain, kidney, and heart tissues. These data provide clues for endogenous roles of P450 within the brain, and possible involvement in the pathogenesis of Parkinson's disease. ^

Culturally sensitive cancer education: Effect on knowledge, cancer fatalism, and participation in mobile mammography screening among African-American women

Purpose. To evaluate the effectiveness of a culturally sensitive educational intervention that used an African American lay survivor of breast cancer to increase knowledge of breast cancer, decrease cancer fatalism, and increase participation in mobile mammography screening among African American women. ^ Design. Experimental pretest/posttest design. ^ Setting. Two predominantly African American churches in a large southwestern metropolitan city. ^ Sample. Participants included 93 African American women, 40 years of age and older. Participants were randomly assigned to an intervention group (n = 48) or a control group (n = 45). ^ Methods. Pretest and post-test measures included the Breast Cancer Knowledge Test and the Powe Fatalism Inventory. In addition, demographic and breast screening practices were collected by questionnaire. The intervention group received a breast cancer educational testimonial from an African American lay survivor of breast cancer, who answered questions and addressed concerns, while stressing the importance of taking responsibility for one's own health and spreading disease prevention messages throughout the African American community. The control group viewed the American Cancer Society “Keep In Touch” video prepared specifically for African American women. Participants in both groups were given culturally sensitive educational materials designed to increase knowledge about breast cancer, and were instructed on breast self-examination by an African American registered nurse, using ethnically appropriate breast models. In addition, after the post-test, all eligible participants were given an opportunity to have a free mammogram via a mobile mammography unit parked at the church. ^ Findings. Participants in the intervention group had a significant increase (p = .03) in knowledge of breast cancer and a significant decrease (p = .000) in fatalism scores compared to those individuals in the control group. The intervention group had a 61% participation rate in screening, while the control group had a 39% participation rate in screening. However, the difference was not statistically significant at the .05 level (p = .07). ^ Conclusions. Results demonstrate that culturally sensitive breast cancer education is successful in increasing knowledge and decreasing cancer fatalism. While there was a trend toward behavior change in the intervention group, more research needs to be done in this area. ^

The pain experience of elderly hospice patients with cancer

Purpose/objectives. A grounded theory design was used to identify, describe, and generate a theoretical analysis of the pain experience of elderly hospice patients with cancer. ^ Sample. Eleven participants over the age of 65, receiving services from a for-profit hospice were interviewed in their homes. ^ Methods. Broad unstructured face to face audio-taped interviews were transcribed verbatim and analyzed using constant-comparative method of analysis. ^ Findings. Pain was described as a hierarchy of chronic, acute, and psychological pain with psychological pain as the worst. Suffering was the basic social problem of pain. Participants dealt with suffering by the basic social process of enduring. Enduring had two sub-processes, maintaining hope and adjusting. Trusting in a higher being and finding meaning were mechanisms of maintaining hope. Mechanisms of adjusting were dealing with uncertainty, accepting, and minimizing pain. ^ Implications for nursing practice. Nurses need to recognize and value the hard work of enduring to deal with suffering. Assisting elderly hospice patients with cancer to address the sub-processes of enduring and their mechanisms can foster enduring. ^

CISPLATIN NEPHROTOXICITY AND ITS EFFECTS ON GENTAMICIN PHARMACOKINETICS

Myelosuppression is a common side effect of anticancer agents such as cisplatin. This makes patients more susceptible to infections. Gentamicin is an aminoglycoside antibiotic that is very effective in the treatment of gram negative infections. Both these drugs are excreted by the kidney, and are also nephrotoxic. Thus, each may affect the disposition of the other. This project deals with the nature and duration of the effects of cisplatin on gentamicin pharmacokinetics in F-344 rats.^ The appropriate cisplatin dose was determined by comparing the nephrotoxicity of four intravenous doses--3, 4, 5, and 6 mg/kg. The 6 mg/kg dose gave the most consistent nephrotoxic effect, with peak plasma urea nitrogen and creatinine levels on the 7th day. Plasma and tissue gentamicin levels were compared between rats given gentamicin alone (30 mg/kg, intraperitoneally, twice a day for four days), and those given cisplatin (6 mg/kg, intraperitoneally) with the first gentamicin dose. Cisplatin caused a significant elevation of gentamicin levels in plasma, liver, and spleen. However, cisplatin given in three weekly doses of 2 mg/kg each, had no effect on plasma or tissue gentamicin levels.^ In order to determine the duration of cisplatin effects, a single dose of gentamicin (30 mg/kg, intravenously) was given to different groups of rats either alone, or on day 1, 4, 7, 15, or 29 following cisplatin (6 mg/kg, intravenously on day 1). Plasma samples were collected through a cannula placed on the external jugular vein at 0.5, 1, 2, 3, 4, 5, and 6 hours after gentamicin; the rats were sacrificed at 24 hours. Cisplatin caused a significant decrease in gentamicin excretion and an elevation of gentamicin levels in plasma, kidneys, liver, and spleen at all the time points that were tested, except with concomitant administration. Plasma urea nitrogen was elevated, and creatinine clearance decreased by the 4th day after cisplatin and these continued to be significantly different even on the 29th day after cisplatin.^ These results demonstrate that cisplatin nephrotoxicity reduced gentamicin excretion for at least a month in F-344 rats. This could increase the risk of toxicity from the second drug by elevating its levels in plasma and tissue. Thus, caution should be exercised when renally excreted drugs are given after cisplatin. ^

Molecular epidemiology of Bacillus anthracis: determining the correct origin

We analyzed and compared strains of Bacillus anthracis isolated from husbandry and industrial anthrax cases in Switzerland between 1952 and 1981 with published data using multiple-locus variable-number tandem repeat analysis. Strains isolated from autochthonous cases of anthrax in cattle belong to genotype B2, together with strains from continental Europe, while human B. anthracis strains clustered with genotype A4. These strains could be traced back to outbreaks of human anthrax that occurred between 1978 and 1981 in a factory processing cashmere wool from the Indian subcontinent. We interpret the worldwide occurrence of B. anthracis strains of cluster A4 to be due to the extensive global trade of untreated cashmere wool during the last century.