Diurnal intraocular pressure curves in healthy rhesus macaques (Macaca mulatta) and rhesus macaques with normotensive and hypertensive primary open-angle glaucoma

PURPOSE

The authors identify any diurnal intraocular pressure (IOP) variation in healthy Cayo Santiago macaques, as well as Cayo Santiago macaques with normotensive and hypertensive primary open-angle glaucoma (POAG), to further evaluate their potential value as a model for human POAG.

METHODS

Twenty-four monkeys (eight animals each of the healthy control, normotensive glaucoma, and hypertensive glaucoma groups) were sedated with ketamine hydrochloride and the IOP measured hourly from 8:00 AM until 3:00 PM with a Tonopen XL applanation tonometer (Mentor, Norwell, MA, U.S.A.). Mean IOP time profiles, mean IOPs at each observation time, and linear trends in mean IOP over time were compared among groups. Intraocular pressure rate-of-change over time and residual variation about the regression line for each individual eye were analyzed. Cup/disc ratio (C/D) was compared with baseline IOP, IOP profile mean and slope, and IOP residual variation.

RESULTS

A significant group and time effect on mean IOP (p = 0.0001 and 0.011, respectively), with highest values at 2:00 PM or 3:00 PM, and a significant increasing linear trend in mean IOP over time in the hypertensive group were observed (p = 0.012). Intermediate readings between control and hypertensive mean IOPs were identified for the normotensive glaucoma group. The biggest range of IOP variation was found in the hypertensive glaucoma monkeys. Higher variations in IOP did not lead to an increase in C/D.

CONCLUSIONS

This study provides evidence that the Cayo Santiago macaques are a valuable model for human normotensive and hypertensive POAG.

Nitrite adulteration of workplace urine drug-testing specimens. I. Sources and associated concentrations of nitrite in urine and distinction between natural sources and adulteration

The active ingredient in the commercial workplace urine drug-testing adulterant, Klear, was previously determined to be nitrite ion. Nitrite adulteration compromises the confirmation of some drugs, notably the marijuana metabolite. A previously reported bisulfite step overcomes some nitrite adulteration, but it cannot do so in every case, which leaves the laboratory to report the specimen as not suitable for testing. Unlike many other adulterants, nitrite is found in normal urine at low concentrations. In order to defend a report of nitrite adulteration, it is necessary to provide evidence that the amount of nitrite in a workplace urine specimen could not arise by normal means. The objectives of this study were to identify all sources of nitrite in urine and the range of concentrations associated with these sources and to determine if nitrite adulteration can be supported based upon a quantitative result. The scientific literature was reviewed for internal and external sources of nitrite and their concentration ranges and are reported. The following specimens were obtained and nitrite concentrations measured by a spectrophotometric method: clinical specimens nitrite positive by test strip (< 15 micrograms/mL); specimens culture positive for nitrate-reducing microorganisms (< 36 micrograms/mL); specimens from patients on medications that may metabolize to nitrite (< 6 micrograms/mL); and drug-test specimens, both negative (< 130 micrograms/mL) and others that appeared to be adulterated with nitrite (range 1910-12,200 micrograms/mL, mean 5910). The literature and the nitrite measurements of this study indicate a substantial difference between concentrations from natural sources compared with adulteration. A quantitative measurement of nitrite by a well-structured assay can provide scientifically valid and forensically defensible proof of adulteration with a nitrite-containing substance.

The relationship between housing characteristics, emotional well-being and the personal empowerment of psychiatric consumer/survivors

In this research, we examine the relationships between the housing characteristics and dimensions of community adaptation for 107 psychiatric consumer/survivors. Hypotheses about which housing characteristics best predict which dimensions of adaptation were made based on previous research and theory. Using a longitudinal research design, we found, after controlling for demographic variables and prior adaptation, that the number of living companions, housing concerns, and having a private room all significantly predicted different dimensions of community adaptation. The findings partially support our theoretical expectations and illuminate the relationship between physical, social and organizational aspects of community-based housing and the adaptation of psychiatric consumer/survivors. We discuss the implications of the results for policy and practice in providing housing for this population.

Flow-injection detector incorporating a screen-printed disposable amperometric biosensor for monitoring organophosphate pesticides

The construction of a wall-jet flow cell, which houses a screen-printed amperometric pesticide biosensor, together with a complete flow-injection system, is described. This system was initially employed in studies to stabilise the enzyme acetylcholinesterase (AChE), which was immobilised on a cobalt phthalocyanine screen-printed carbon electrode to form a biosensor. A combination of dextran sulfate and lactitol, and carbodiimide for enzyme immobilisation, resulted in biosensor lifetimes of at least 76 d (at 37 degrees C). Flow-injection and biosensor conditions were optimised, then the system was evaluated by monitoring the model organophosphate pesticides (OP) dichlorvos and paraoxon. The detection limits were 7 x 10(-11) mol dm-3 (for 1 U of AChE) and 4 x 10(-11) mol dm-3 (for 0.05 U of AChE), respectively, which are better than for other electrochemical methods. Initial evaluations on two river water samples have been carried out to test the validity of the system for OP determination in field samples.

Comparison of the morphological transforming activities of dibenzo[a,l]pyrene and benzo[a]pyrene in C3H10T1/2CL8 cells and characterization of the dibenzo[a,l]pyrene-DNA adducts

C3H10T1/2CL8 (C3H10T1/2) mouse embryo fibroblasts were used to study the in vitro carcinogenic activities of dibenzo[a,l]pyrene (DB[a,l]P) and benzo[a]pyrene (B[a]P). The morphological transforming activities of these rodent carcinogens were compared using replicate concentration-response studies. In concentration ranges where both polycyclic aromatic hydrocarbons (PAHs) were active, DB[a,l]P proved to be four to 12 times as potent as B[a]P based on concentration. At lower concentrations DB[a,l]P was active at 0.10 and 0.20 microM, concentrations where B[a]P was inactive. This makes DB[a,l]P the most potent non-methylated PAH evaluated to date in C3H10T1/2 cells. DNA adducts of DB[a,l]P in C3H10T1/2 cells were analyzed by both TLC and TLC/HPLC 32P-postlabeling methods using mononucleotide 3'-phosphate adduct standards derived from the reactions of anti-DB[a,l]P-11,12-diol-13,14-epoxide (anti-DB[a,l]PDE) and syn-DB[a,l]P-11,12-diol-13,14-epoxide (syn-DB[a,l]PDE) with deoxyadenosine 3'-monophosphate and deoxyguanosine 3'-monophosphate. All of the DNA adducts observed in C3H10T1/2 cells treated with DB[a,l]P were identified as being derived from the metabolism of DB[a,l]P to its fjord region diol epoxides through DB[a,l]P-11,12-diol. The predominant adduct was identified as an anti-DB[a,l]PDE-deoxyadenosine adduct. Other major adducts were anti-DB[a,l]PDE-deoxyguanosine and syn-DB[a,l]PDE-deoxyadenosine adducts with minor amounts of syn-DB[a,l]PDE-deoxyguanosine adducts. These DNA adduct data are consistent with similar findings of DB[a,l]PDE-deoxyadenosine adducts in mouse skin studies and human mammary cells in culture.

A positive cannabinoids workplace drug test following the ingestion of commercially available hemp seed oil

A commercially available health food product of cold-pressed hemp seed oil ingested by one volunteer twice a day for 4 1/2 days (135 mL total). Urine specimens collected from the volunteer were subjected to standard workplace urine drug testing procedures, and the following concentrations of 11-nor-delta9- tetrahydrocannabinol carboxylic acid (9-THCA) were detected: 41 ng/mL 9-THCA at 45 h, 49 ng/mL at 69 h, and 55 ng/mL at 93 h. Ingestion was discontinued after 93 h, and the following concentrations were detected: 68 ng/mL at 108 h, 57 ng/mL at 117 h, 31 ng/mL at 126 h, and 20 ng/mL at 142 h. The first specimen that tested negative (50 ng/mL initial immunoassay test, 15 ng/mL confirmatory gas chromatographic-mass spectrometric test) was at 146 h, which was 53 h after the last hemp seed oil ingestion. Four subsequent specimens taken to 177 h were also negative. This study indicates that a workplace urine drug test positive for cannabinoids may arise from the consumption of commercially available cold-pressed hemp seed oil.

Intracarotid infusion of RMP-7, a bradykinin analog, and transport of gallium-68 ethylenediamine tetraacetic acid into human gliomas

The bradykinin analog, RMP-7, was investigated for its ability to increase selectively the transport of 68Ga ethylenediamine tetraacetic acid (EDTA) into recurrent malignant gliomas in nine patients. For each patient, two position emission tomography (PET) studies (one with and one without RMP-7) were performed. For studies with RMP-7, 10 to 300 ng/kg of the compound was infused into the supraophthalmic carotid artery over 15 minutes. In each PET study, a sequence of PET scans was initiated simultaneously with an intravenous bolus of 68Ga EDTA (5-10 mCi). Arterial samples were taken to provide the input function. All PET scans were coregistered to the magnetic resonance (MR) images of the patient. Regions of interest were defined for tumor and normal tissue regions on MR images and were copied to the coregistered PET dynamic images to provide brain tissue-time activity curves. The constant (Ki) for the transport of gallium-68 from plasma to brain tissue was determined using a simple compartmental model. Intracarotid infusion of RMP-7 significantly increased transport into tumor regions with an average increase of 46 +/- 42% (mean +/- standard deviation, p < 0.05). Permeability in normal tissue regions was not significantly increased. Tumors in three of six patients treated with 300 ng/kg RMP-7 and carboplatin had at least a 50% reduction in tumor volume as measured by MR imaging. Intracarotid infusion of RMP-7 is a novel technique for selective delivery of antitumor compounds into brain tumors.

Social networks, social support, personal empowerment, and the adaptation of psychiatric consumers/survivors: path analytic models

In this paper, we examine the relationships between social network characteristics, personal empowerment, social support, and adaptation of psychiatric consumer/survivors. Using path model analyses, we found that: (1) personal empowerment had statistically significant direct effects on positive affect, meaningful activity, and negative affect; (2) positive social support mediated the relationship between the proportion of women in consumer/survivors' networks and positive affect and meaningful activity; and (3) negative social interaction mediated the relationship between consumer/survivors' gender and negative affect. The results point out the importance of gender effects in social support processes, the differential association between type of social interaction (positive vs negative) and adaptation indices (positive vs negative), and the importance of personal empowerment for consumer/survivors' adaptation. We discuss the findings in terms of their implications for further research and community-based housing programmes for psychiatric consumer/survivors.

Improving ion mass ratio performance at low concentrations in methamphetamine GC-MS assay through internal standard selection

In federally regulated drug testing, laboratories must identify and quantitate drugs and their breakdown products by gas chromatography-mass spectrometry (GC-MS) to a concentration that is at least 60% below the cutoff concentration for reconfirmation purposes. Use of methamphetamine-d5 as an internal standard in routine testing with derivatization by HFBA was found to contribute m/z 91 and 118 ions to the same ions from the nondeuterated methamphetamine in the specimen. This resulted in poor chromatography and occasionally caused the 91/254 and 118/254 ion mass ratios to exceed the +20% acceptance limit established in the calibration process at low concentrations. The analogues methamphetamine-d8 and -d11 were evaluated for contributions to the nondeuterated methamphetamine ion fragments. Methamphetamine-d8 produced m/z 91 and 118 ions, but in less abundance than methamphetamine-d5. Methamphetamine-d11 was found to produce little or no detectable m/z 91 or 118. Replacing methamphetamine-d5 with methamphetamine-d11 eliminates this problem and allows the assay to consistently produce ion mass ratios and acceptable chromatography sufficient for identifying and quantitating methamphetamine at 60% below the 500-ng/mL cutoff concentration.

Radiation protection systems for the final focus test beam at SLAC

The Final Focus Test Beam (FFTB) is a new beam line at the Stanford Linear Accelerator Center designed to test new beam optics concepts, hardware, and techniques necessary to achieve and measure the small spot sizes required for future generations of high-energy e+e- linear colliders. The FFTB takes a 47 GeVc-1, 1 kW electron beam at the end of the Stanford Linear Accelerator Center linear accelerator and transports it to the FFTB beam dump. A radiation protection system was designed and installed for the FFTB with the primary goal that the integrated dose equivalent outside the shielding resulting from beam loss would not exceed 10 mSv y-1. This system is comprised of shielding, a beam containment system and a personnel protection system. This paper presents various aspects of radiation safety at Stanford Linear Accelerator Center that were considered in the design of the FFTB radiation protection system. Beam tests were conducted in which the performance of various beam containment devices and the shielding effectiveness were evaluated. Preliminary results from these tests are presented.

Factors associated with intention to undergo annual prostate cancer screening among African American men in Philadelphia

BACKGROUND

This study assesses whether African American men in Philadelphia are receptive to annual prostate cancer screening. Factors associated with intention to undergo prostate cancer screening are also identified.

METHODS

The authors randomly selected 218 African American men from the patient population of a large primary care practice in Philadelphia. The men were 40 to 70 years of age and were available for a telephone survey. Responses to survey items defined by the Preventive Health Model were collected from 154 respondents (71%). Univariate and multivariate analyses of screening intention were performed using survey data on sociodemographic background and medical history; knowledge, attitudes, and beliefs about prostate cancer and screening; social support and influence; and, intention to undergo a screening examination.

RESULTS

Overall, 69% of subjects reported that they intended to have annual prostate cancer screening. Logistic regression analyses showed that subject belief in screening efficacy (P=0.0002) were positively and significantly associated with intention to screen.

CONCLUSIONS

Findings reported here show that African American men in an urban primary care practice setting are receptive to annual prostate cancer screening and that psychologic and social influence factors are associated with screening intention. The data highlight the need for health care professionals to provide education and advice regarding prostate cancer care to men in this population.

Benzo[b]fluoranthene: tumorigenicity in strain A/J mouse lungs, DNA adducts and mutations in the Ki-ras oncogene

The polycyclic aromatic hydrocarbon benzo[b]fluoranthene (B[b]F) is a pervasive constituent of environmental combustion products. We sought to examine the lung tumorigenic activity of B[b]F in strain A/J mice, to study the relationship between formation and decay of B[b]F-DNA adducts and to examine mutations in the Ki-ras proto-oncogene in DNA from B[b]F-induced tumors. Mice were given i.p. injections of 0, 10, 50, 100 or 200 mg/kg body wt and lung adenomas were scored after 8 months. B[b]F induced significant numbers of mouse lung adenomas in a dose-related fashion, with the highest dose (200 mg/kg) yielding 6.95 adenomas/ mouse, with 100% of the mice exhibiting an adenoma. In mice given tricaprylin, the vehicle control, there were 0.60 adenomas/mouse, with 55% of the mice exhibiting an adenoma. Based on dose, B[b]F was less active than benzo[a]pyrene. DNA adducts were analyzed qualitatively and quantitatively by 32P-post-labeling in lungs of strain A/J mice 1, 3, 5, 7, 14 and 21 days after i.p. injection. Maximal levels of adduction occurred 5 days after treatment with the 200 mg/kg dose group, producing 1230 amol B[b]F-DNA adducts/microgram DNA. The major B[b]F-DNA adduct was identified by co-chromatography as trans-9, 10-dihydroxy-anti-11, 12-epoxy-5-hydroxy-9, 10, 11, 12-tetra-hydro-B[b]F-deoxyguanosine. Approximately 86% of the tumors had a mutation in codon 12 of the Ki-ras oncogene, as determined by direct DNA sequencing of PCR-amplified exon 1 and single-stranded conformation polymorphism analysis. Analysis of the Ki-ras mutation spectrum in 25 of 29 B[b]F-induced tumors revealed the predominant mutation to be a G-->T transversion in the first or second base of codon 12, congruous with the DNA adduct data. Our data are consistent with previous reports in mouse skin implicating a phenolic diol epoxide as the proximate carcinogenic form of B[b]F that binds to guanine.

Localized or systemic in vivo heat inactivation of human immunodeficiency virus (HIV): a mathematical analysis

Temperatures > or = 42 degrees C, maintained for > or = 25 min, inactivate approximately 25% of human immunodeficiency virus (HIV). HIV-infected T cells are more sensitive to heat than healthy lymphocytes, and susceptibility increases when the cells are presensitized by exposure to tumor necrosis factor. Thus, induction of a whole-body hyperthermia or hyperthermia specifically limited to tissues having a high viral load is a potential antiviral therapy for acquired immunodeficiency syndrome (AIDS). Accordingly, we incorporated therapeutic hyperthermia into an existing mathematical model that evaluates the interaction between HIV and CD4+ T cells. Given the assumptions and limitations of this model, the results indicate that a daily therapy lowering the population of actively infected cells by 40% or infectious virus by 40% would effectively reverse the depletion of T cells. In contrast, a daily decline of 20% of either actively infected cells or infectious virus would have a marginal effect. However, daily reduction by 20% of both actively infected cells and infectious virus could restore T-cell numbers, assuming that permanent damage had not been inflicted on the thymus. Since daily treatments would probably be excessively stressful, whole-body hyperthermia seems unlikely to be clinically useful. In contrast, heating directed specifically to areas of viral concentration may be effective and have a suitable risk/benefit ratio.

Modulation of cellular macromolecular synthesis by coronavirus: implication for pathogenesis

Infection with the murine coronavirus strain JHM decreases cell surface expression of major histocompatibility complex class I antigens. Northern blots showed that JHM virus infection rapidly reduced the level of actin mRNA, whereas the levels of major histocompatibility complex class I and tubulin mRNAs were reduced only slightly. By contrast, the mRNA levels of interleukin 1 beta, colony-stimulating factor 1 receptor, and tumor necrosis factor alpha increased following infection.

Morphological transformation and DNA adduct formation by dibenz[a,h]anthracene and its metabolites in C3H10T1/2CL8 cells

The major routes of metabolic activation of dibenz[a,h]-anthracene (DBA) have been studied in transformable C3H10T1/2CL8 (C3H10T1/2) mouse embryo fibroblasts in culture. The morphological transforming activities of three potential intermediates formed by metabolism of DBA by C3H10T1/2 cells, trans-3,4-dihydroxy-3,4-dihydro-DBA-(DBA-3,4-diol), trans-dihydroxy-3,4-dihydro-DBA-anti-1,2-oxide (DBA-3,4-diol-1,2-oxide) and DBA-5,6-oxide were determined. DBA-3,4-diol-1,2-oxide was a strong morphological transforming agent giving a mean of 73% dishes with Type II or III foci and 1.63 Type II and III foci per dish at 0.5 microgram/ml. DBA-3,4-diol produced a mean of 42% dishes with Type II or III foci and 0.81 Type II and III foci per dish at 2.5 micrograms/ml. DBA gave a mean of 24% dishes with Type II or III foci and 0.29 Type II and III foci per dish at 2.5 micrograms/ml. DBA-5,6-oxide was found to be inactive. DNA adducts of DBA, DBA-3,4-diol, DBA-3,4-diol-1,2-oxide, DBA-1,4/2,3-tetrol and DBA-5,6-oxide in C3H10T1/2 cells were analyzed by 32P-postlabeling method. DBA gave 11 adducts, nine of which were observed in the DNA of cells treated with DBA-3,4-diol and seven from cells treated with DBA-3,4-diol-1,2-oxide. Two of these adducts that appear in each of the treatment groups have been identified as the product of the interaction of DBA-3,4-diol-1,2-oxide with 2'-deoxyguanosine. Furthermore, there is evidence for DBA-DNA adducts in cells treated with DBA, DBA-3,4-diol and DBA-3,4-diol-1,2-oxide arising from metabolism to (+,-)-trans,trans-3,4,10,11-tetrahydroxy-3,4,10,11-tetrahydro-DBA (DBA-3,4,10,11-bis-diol). These results are based on co-migration of C3H10T1/2 DNA adducts with skin DNA adducts formed after topical treatment of mice with DBA-3,4,10,11-bis-diol. In C3H10T1/2 cells, DBA is metabolically activated through DBA-3,4-diol, which is further activated via the DBA-3,4-diol-1,2-oxide and DBA-3,4,10,11-bis-diol pathways. No evidence is provided for the metabolism of DBA by the K-region pathway.

Life event stress and myocardial reinfarction: a prospective study

Earlier studies of life event stress in coronary heart disease (CHD) have been flawed by cross-sectional design and inadequate methods for assessing life-event stress. This 3-year prospective study of acute myocardial infarct (AMI) patients reveals significant independent associations between acute and chronic stressors at first admission, and risk of recurrent AMI and death, occurring in the 3 years of follow-up. Relative risks of reinfarction (or death from reinfarction) in the entire sample, for acute events and chronic difficulties were, 2.5 and 2.3 respectively and were statistically significant. When subjects admitted with first AMI were considered alone, relative risks were 3.1 and 4.1 respectively. The clinical significance of these findings is discussed.

The development of a mental health coalition: a case study

Described the development of a local-level mental health coalition to advocate for housing and community support programs for psychiatric consumer/survivors. Resource mobilization theory was used as a framework from which to view and understand the origins, goals, tactics, and outcomes of the coalition. Data were presented indicating that the coalition played a role in obtaining increased funding for housing and community support programs. Also, there was an emphasis on consumer/survivor and family participation in the change process. Benefits and limitations of the coalition after 6 years of operation were reviewed and compared with other advocacy coalitions in mental health.

Cyclopenta[cd]pyrene-induced tumorigenicity, Ki-ras codon 12 mutations and DNA adducts in strain A/J mouse lung

Cyclopenta[cd]pyrene (CPP) is a ubiquitous cyclopenta-fused polycyclic aromatic hydrocarbon. CPP is highly genotoxic in bacterial and mammalian systems inducing gene mutations, sister chromatid exchanges and morphological transformation. CPP is a mouse skin carcinogen, a mouse skin tumor initiator and induces pulmonary tumors in newborn mice. We have examined the tumorigenic activity of CPP in strain A/J mice, have determined the formation and persistence of CPP-induced DNA adducts in lung tissue, and analyzed the mutational spectrum in the Ki-ras oncogene from CPP-induced tumors. CPP dissolved in tricaprylin was administered by i.p. injection to male A/J mice (20 mice/dose) at 0, 10, 50, 100 and 200 mg/kg. Animals were killed 8 months later and the lungs removed, fixed, and surface adenomas enumerated. CPP proved to be highly tumorigenic in A/J mice in terms of inducing lung adenomas. The observed tumor multiplicities (lung adenomas/mouse) were: 97.7 +/- 28.7 at 200 mg/kg, 32.8 +/- 15.4 at 100 mg/kg, 4.63 +/- 2.11 at 50 mg/kg and 0.58 +/- 0.82 at 10 mg/kg. Tricaprylin-treated controls produced 0.60 +/- 0.58 lung adenomas/mouse. Groups of mice treated under the same dosing conditions as those in the tumor studies were killed 1, 3, 7, 14 and 21 days after treatment. The lungs were removed, and the DNA was subjected to DNA adduct analysis by the 32P-postlabeling method. Total CPP-DNA adducts in mouse lung peaked at day 3 with 5870 amol CPP adducts/micrograms DNA after a single dose of 200 mg/kg. DNA adduct levels decreased to 1800 amol CPP adducts/micrograms DNA at day 21. Qualitative DNA adduct analysis revealed four major adducts and one minor adduct. Co-chromatography of the lung DNA from CPP-treated mice with calf thymus DNA treated with CPP-3,4-oxide indicated that all DNA adducts were oxide derived and comparison with CPP-3,4-oxide-treated polydeoxyguanylic acid suggests that almost all of these adducts are CPP-3,4-oxide-2'-deoxyguanosine adducts. Ki-ras codon 12 mutation analysis of the DNA from tumors taken from the 100 and 200 mg/kg CPP dose groups demonstrated the following patterns: GGT-->CGT (50%); GGT-->GTT (15%); GGT-->TGT (25%); GGT-->GAT (10%). We conclude that CPP is highly tumorigenic in the A/J mouse lung adenoma model, being five times more active than benzo[a]pyrene. This is unlike the result of CPP as a mouse skin tumorigen or tumor initiator in which CPP is considerably less potent than benzo[a]pyrene.(ABSTRACT TRUNCATED AT 400 WORDS)

Effects of mouse hepatitis virus infection on host cell metabolism

A time dependent decrease in cell surface expression of major histocompatibility complex (MHC) class 1 proteins was found during JHMV infection of the mouse macrophage J774.1 cells line by radioimmunoassay. MHC class I, actin and CSF-1 receptor mRNA levels were also found to decrease during infection. Surprisingly, not all host cell mRNA were similarly affected, suggesting that the apparent MHV-induced translational shut off of host cell protein synthesis during infection was specific for only some host cell mRNAs. Interestingly, two mRNAs found to be refractory to JHMV infection encode monokines, suggesting a role in pathogenesis. To understand the mechanism(s) of this preferential mRNA stability and the apparent shut off of host cell mRNA, translation lysates were prepared from infected and uninfected cells. Translation of host mRNAs in these extracts showed no apparent loss of translational ability in the infected cells vs. the uninfected cells; however, viral mRNAs were preferentially translated in the lysates from the infected cells. Chimeric mRNAs containing the MHV leader upstream of a globin reporter gene showed that preferential translation was a property of the MHV leader RNA. Deletional analysis showed that the sequences responsible for this cis translational augmentation are in a 12 nucleotide (nt) tract at the 3' end of the leader. The previously reported interaction of the nucleocapsid protein with these nts suggest that it may play a role in translational augmentation of MHV mRNAs.

Emotional well-being of separated and married women: long-term follow-up study

Separated and married women were studied longitudinally. Recently separated women reported more growth-oriented coping and positive life changes than did married women, but no significant differences were evident six years later. Life strains at early time intervals predicted emotional well-being at the last time interval, and coping served a stress-buffering function over time.

Quantitative and temporal relationships between DNA adduct formation in target and surrogate tissues: implications for biomonitoring

DNA-carcinogen adducts offer a potential dosimeter for environmental genotoxicants reaching the exposed individual. Because the target tissues for many chemical carcinogens are not readily accessible for monitoring adducts in humans, peripheral blood lymphocytes (PBLs) have served as surrogate sources of exposed DNA. Both benzo[a]pyrene (BaP) and benzo[b]fluoranthene (BbF) are widely distributed in the environment as components of complex mixtures, such as automobile exhaust, cigarette smoke, foods, water, and urban air. Thus, human exposure to these chemicals is widespread, and they probably contribute to overall human lung cancer risk. The interpretation of the results of such studies would be enhanced by an understanding of the pharmacokinetics of specific DNA adduct formation and persistence in both target and surrogate tissues. Polycyclic aromatic hydrocarbons (PAHs) were administered to male Sprague-Dawley rats IP at 100 mg PAH/kg body weight. Lung, liver, and PBL tissues were harvested 1, 3, 7, 14, 28, and 56 days after treatment. DNA was extracted from each tissue and 32P-postlabeling analysis of DNA adducts with nuclease P1 enhancement was conducted. In all three tissues, BaP-DNA adducts exhibit a similar pattern, reaching a maximum at 3-4 days, followed by a decrease to 56 days. For BbF, the maximum DNA adduct levels in each tissue were between 5 and 14 days after injection. By 56 days after administration, the total adducts remaining in all tissues were measurable. Correlation analyses of the amount of DNA adducts in lung or liver compared to those found in the PBL of the same animals suggest a range of correlations (R2 = 0.67-0.83).(ABSTRACT TRUNCATED AT 250 WORDS)

Fatty acid profiles of major food sources of howler monkeys (Alouatta palliata) in the neotropics

Wild howler monkeys (Alouatta palliata) get most of their calories from carbohydrates (65%) and fats (18%) of native tropical plants, but little is known about their intake of individual fatty acids. The fatty acid composition of several natural food sources of howler monkeys collected in Panama was determined by gas-liquid chromatography. The predominant fatty acids were palmitic (30%), linoleic (23%), alpha-linolenic (16%) and oleic (15%). Fatty acids with less than 16, and more than 18, carbon chains were uncommon (0-7%). Although total saturated fatty acids were high in some specific food sources (22-54% of total fatty acids and 8 energy %), most of the calories from fat in the animals' diets are derived from mono- and polyunsaturated fatty acids (9.75 energy %). All food sources had significant amounts of the omega-3 fatty acid, alpha-linolenic acid (2.9 energy %). In terms of human diets, the howler monkey's fat consumption would not be considered atherogenic. Unless these animals show a particular adverse susceptibility to dietary fat, it is unlikely that their fat intake is the primary cause of the low, but significant, incidence of atherosclerosis that develops in these animals in the wild state.

The quantitative conversion of morphine 3-beta-D glucuronide to morphine using beta-glucuronidase obtained from Patella vulgata as compared to acid hydrolysis

Methods to confirm morphine in urine require hydrolysis to liberate morphine from its 3-beta-D glucuronide (M-3G) conjugate. Lengthy enzyme hydrolysis procedures prolong testing turnaround time whereas rapid enzyme methods may produce a low conversion of M-3G to morphine. The purpose of this study was to evaluate the quantitative conversion of M-3G to morphine in human urine using a thermally stable beta-glucuronidase isolated from Patella vulgata; to compare these findings with those obtained from acid hydrolysis; and to compare between-run imprecision for both hydrolysis methods. We found both enzyme and acid hydrolysis techniques to be efficient, giving 90.4% and 92.8% conversion of M-3G to morphine, respectively. Also, both methods were found to be reproducible. Over a 14 week period, 20 opiate confirmation batches were analyzed by each hydrolysis method; the coefficient of variation for morphine liberated from M-3G was 5.5% for enzyme hydrolysis and 2.7% for acid hydrolysis.

Genotoxic effects of cyclopenta-fused polycyclic aromatic hydrocarbons in isolated rat hepatocytes and rabbit lung cells

Benz[j]aceanthrylene (B[j]A) and benz[l]aceanthrylene (B[l]A), two isomeric cyclopenta polycyclic aromatic hydrocarbons (CP-PAH) structurally related to 3-methylcholanthrene, were studied with respect to their genotoxic effects in isolated liver and lung cells. Both compounds were found to cause DNA adducts measured by the 32P-postlabelling technique. The level of DNA-adducts in rat hepatocytes exposed to 30 micrograms/ml B[l]A and B[j]A for 4 h were 46.5 +/- 22.0 and 8.3 +/- 5.1 fmol/micrograms DNA respectively. Using butanol extractions, the major and one of the minor B[j]A adducts co-chromatographed with B[j]A-1,2-oxide adducts of 2'-deoxyadenosine and 2'-deoxyguanosine. Thus, oxidation at the cyclopenta-ring of B[j]A appears to be an important activation pathway. In hepatocytes, 3-30 micrograms/ml of B[j]A and B[l]A induced DNA damage and repair measured both as increased alkaline elution of DNA and as increased incorporation of [3H]TdR in the DNA. B[l]A was somewhat more potent than B[j]A in inducing DNA repair. Reactive CP-PAH intermediates formed in the hepatocytes caused mutations in Salmonella typhimurium TA98 upon co-incubation. DNA adducts were also observed in isolated rabbit lung cells exposed to 30 micrograms/ml B[l]A or B[j]A for 2 h. A total of 14.5 +/- 6.9, 2.9 +/- 2.1 and 0.2 +/- 0.6 fmol B[l]A adducts/micrograms DNA were observed in Clara cells, type II pneumocytes and alveolar macrophages respectively. The main B[l]A adduct observed in the liver cells was not found in the lung cells. On the other hand, the levels of B[j]A adducts in the lung cells were in the range 4-14% of that found in liver cells, and no major differences between the various lung cells were observed. Neither B[l]A nor B[j]A induced DNA damage measured by alkaline elution in the lung cells, indicating that these adducts are not alkali labile.

Ki-ras oncogene mutations in tumors and DNA adducts formed by benz[j]aceanthrylene and benzo[a]pyrene in the lungs of strain A/J mice

Strain A/J mice received intraperitoneal injections of benz[j]aceanthrylene (B[j]A) or benzo[a]pyrene (B[a]P). At 24, 48, and 72 h, lung tissues were removed for analysis of B[a]P- or B[j]A-derived DNA adduct formation during the first 3 d of exposure. One group of mice exposed to these hydrocarbons was kept for 8 mo to determine lung tumor multiplicity, the occurrence of mutations in codons 12 and 61 of the Ki-ras gene in the tumors that arose, the relationship between Ki-ras oncogene mutations in tumors, and the presence and quantity of genomic DNA adducts. The major DNA adduct in the lungs of mice exposed to B[a]P was N2-(10 beta-[+B, 7 alpha, 9 alpha-trihydroxy-7,8,9,10-tetrahydrobenzo[a]pyrene]yl)-deoxyguanosine (BPDE-I-dGuo) arising from bay-region diolepoxide activation of B[a]P and was consistent with the occurrence of tumors with mutations GGT-->TGT (56%), GGT-->GTT (25%), and GGT-->GAT (19%) in codon 12, all involving mutations of a guanine. B[j]A, a demethylated analogue of 3-methylcholanthrene (3-MCA) with an unsaturated cyclopenta ring, produced 16-to 60-fold more tumors at equivalent doses than did B[a]P; the mutations in tumors were GGT-->TGT (4%), GGT-->GTT (30%), and GGT-->CGT (65%). Analysis of adduction patterns in DNA suggested that B[j]A was activated to form DNA-binding derivatives in A/J mouse lungs primarily at the cyclopenta ring even though B[j]A contains a bay region. As reported in the published literature, the mutation spectrum induced by 3-MCA in Ki-ras codon 12 of mouse cells is similar to that of B[a]P but not to that of its close relative B[j]A. In contrast to B[j]A, 3-MCA is activated mostly via a bay-region diol-epoxide since its cyclopenta ring is saturated and not easily epoxidates. Therefore, we propose that the GGT-->CGT mutations produced by B[j]A in Ki-ras codon 12 were mostly the result of cyclopenta-ring-derived adducts.