The suitability of the urinary metabolite 1-hydroxypyrene as an index of poly nuclear aromatic hydrocarbon bioavailability from workers exposed to carbon black

Levels of airborne dust have been measured in the breathing zone of five warehouse packers in a carbon black manufacturing plant on consecutive days over 1 week. Post-shift urine samples were collected on individuals over the week and the concentration of the pyrene metabolite 1-hydroxypyrene have been measured. A questionnaire was used to assess the likelihood of potential confounding factors, such as direct exposure to feedstock oil, as well as smoking and diet. The arithmetic mean both of airborne dust and of excreted 1-hydroxypyrene for each individual have been correlated (a) with the constraint that the regression line pass through the origin, and (b) without this constraint. The slope of the regression through the origin was significant and that of the second regression (not through the origin) was not. The statistical test to determine whether excretion on days after Monday was higher than that on Monday itself proved highly significant. The results suggest that 1-hydroxypyrene may be a useful indicator of exposure to the PNAs adsorbed onto carbon black.

Clinical experience with erythropoietin in continuous ambulatory peritoneal dialysis

The purpose of this project was to determine a safe and effective Epogen (EPO) subcutaneous administration schedule for patients who were on continuous ambulatory peritoneal dialysis. To comply with the manufacturer's recommendation to enter a vial only once, a dosing regimen had to be established that used a standard dose of 2,000 or 4,000 units. The goal was to determine the frequency of administration that would achieve and maintain the target hematocrit. Twenty-six patients participated. The starting dose of 4,000 units was administered either two or three times per week. An average 8.3% point increase in hematocrit was seen in 8 weeks. When the target hematocrit of 33% to 35% was reached, the dose and or frequency of administration was decreased. Maintenance doses were established at 2,000 or 4,000 units weekly or biweekly. We were able to meet and maintain the target hematocrit by using 2,000 or 4,000 units per dose and adjusting the frequency.

Intergenerational Partners Project: a model linking elementary students with senior center volunteers

Age-integrated programming has become an effective way to bring the young and old closer together. This paper describes a 9-month intergenerational program designed to establish a more intimate involvement between a group of 4th graders and elderly volunteers from Senior Neighbors. The format used to organize the project is presented, and ongoing activities and program benefits are identified. The goals of this project have been richly met, reducing students' fears and misconceptions about aging and providing a satisfying experience for the seniors.

The effectiveness of ice- and Freon-based personal cooling systems during work in fully encapsulating suits in the heat

The use of cooling garments in conjunction with fully encapsulating suits offers the potential for reducing the heat strain for workers at hazardous waste sites and chemical emergencies. This study examined the use of ice- and Freon-based cooling garments during exercise in the heat while wearing a U.S. Coast Guard chemical response suit (CRS), a fully encapsulating, Teflon-coated, Nomex suit. Responses of nine healthy men (mean age 28.8 yr) were measured during moderate exercise at 30% of their maximal oxygen consumption in an environmental chamber maintained at 33.9 degrees C (93 degrees F) and 82% relative humidity. The four randomly assigned experimental conditions were (1) the CONTROL, consisting of a self-contained breathing apparatus (SCBA) worn in conjunction with shorts, shirt, helmet, and shoes; (2) the CRS, consisting of the Coast Guard CRS worn with shorts, shirt, SCBA, helmet, gloves, and boots; (3) the ICE, which was identical to the CRS ensemble, with the addition of an ice and water cooling system; and (4) the FREON, which was also identical to the CRS ensemble, with the addition of a Freon-based cooling system. To the author's knowledge, this paper is the first to quantify and compare a Freon-based system with a circulating ice water system. The subjects performed repeated rest/work intervals for 45 min, followed by a 10-min recovery period. Measured physiological responses, including heart rate, skin, rectal, and axillary temperatures, were recorded at 1-min intervals during the tests.(ABSTRACT TRUNCATED AT 250 WORDS)

Streptococcus pneumoniae-stimulated macrophages induce neutrophils to emigrate by a CD18-independent mechanism of adherence

Neutrophil adherence to and emigration across endothelium are in large part dependent upon the neutrophil membrane CD11/CD18 glycoprotein complex. Recently, however, we have demonstrated that some stimuli can elicit neutrophil emigration in the lung by a CD18-independent pathway. We examined further the mechanism involved in CD18-independent emigration in a rabbit model of inflamed peritoneum. Neutrophil emigration in the peritoneum induced by instillation of E. coli and S. pneumoniae was studied under four experimental conditions: Group 1--normal peritoneum, Group 2--peritoneum primed with protease peptone to increase the number of macrophages, Group 3--peritoneum treated by protease peptone instillation and then depleted of the increased macrophage population, and Group 4--peritoneum with macrophages transplanted from animals enriched as in Group 2. Experiments were run in pairs with animals in each group assigned to receive either saline (control) or monoclonal antibody (MAb) 60.3 prior to bacterial instillation in the peritoneum. Neutrophil emigration in response to E. coli was greater than 86% inhibited by MAb 60.3 in both the normal and the macrophage-enriched peritoneum. Neutrophil emigration in response to S. pneumoniae was inhibited greater than 85% in the normal peritoneum and the macrophage-enriched and the transplanted macrophage peritoneum. These data indicate that macrophages can augment PMN emigration by a non-CD18 mechanism, and may explain the increased sensitivity of organs with large resident macrophage populations, liver and lung, to injury following shock and sepsis.

Visible-light system for detecting doxorubicin contamination on skin and surfaces

A portable system that uses fluorescence stimulated by visible light to identify doxorubicin contamination on skin and surfaces was studied. When activated by violet-blue light in the 465-nm range, doxorubicin fluoresces, emitting orange-red light in the 580-nm range. The light source to stimulate fluorescence was a slide projector with a filter to selectively pass short-wave (blue) visible light. Fluorescence was both observed visually with viewing spectacles and photographed. Solutions of doxorubicin in sterile 0.9% sodium chloride injection were prepared in nine standard concentrations ranging from 2 to 0.001 mg/mL. Droplets of each admixture were placed on stainless steel, laboratory coat cloth, pieces of latex examination glove, bench-top absorbent padding, and other materials on which antineoplastics might spill or leak. These materials then were stored for up to eight weeks and photographed weekly. The relative ability of water, household bleach, hydrogen peroxide solution, and soap solution to deactivate doxorubicin was also measured. Finally, this system was used to inspect the antineoplastic-drug preparation and administration areas of three outpatient cancer clinics for doxorubicin contamination. Doxorubicin fluorescence was easily detectable with viewing spectacles when a slide projector was used as the light source. The photographic method was sensitive for doxorubicin concentrations from 2.0 to 0.001 mg/mL. Immersion of study materials in bleach for one minute eliminated detectable fluorescence. Doxorubicin contamination is detectable for at least eight weeks in the ambient environment. Probable doxorubicin contamination was detected in two of the three clinics surveyed. A safe, portable system that uses fluorescence stimulated by visible light is a sensitive method for detecting doxorubicin on skin and surfaces.

Obituary - Gill Geary

Stockport Branch Royal College of Nursing deeply regret to announce the untimely passing of Gill Geary, Steward, who died suddenly on Monday 11 December 1989, age 55 years.

Handgun regulations, crime, assaults, and homicide. A tale of two cities

To investigate the associations among handgun regulations, assault and other crimes, and homicide, we studied robberies, burglaries, assaults, and homicides in Seattle, Washington, and Vancouver, British Columbia, from 1980 through 1986. Although similar to Seattle in many ways, Vancouver has adopted a more restrictive approach to the regulation of handguns. During the study period, both cities had similar rates of burglary and robbery. In Seattle, the annual rate of assault was modestly higher than that in Vancouver (simple assault: relative risk, 1.18; 95 percent confidence interval, 1.15 to 1.20; aggravated assault: relative risk, 1.16; 95 percent confidence interval, 1.12 to 1.19). However, the rate of assaults involving firearms was seven times higher in Seattle than in Vancouver. Despite similar overall rates of criminal activity and assault, the relative risk of death from homicide, adjusted for age and sex, was significantly higher in Seattle than in Vancouver (relative risk, 1.63; 95 percent confidence interval, 1.28 to 2.08). Virtually all of this excess risk was explained by a 4.8-fold higher risk of being murdered with a handgun in Seattle as compared with Vancouver. Rates of homicide by means other than guns were not substantially different in the two study communities. We conclude that restricting access to handguns may reduce the rate of homicide in a community.

Effect of positive-end expiratory pressure on accuracy of thermal-dye measurements of lung water

The thermal-dye indicator dilution technique of measuring extravascular lung water (EVLW-TD) correlates well with gravimetric measurement of lung water (EVLW-GR) when no positive-end expiratory pressure (PEEP) is used in both normal and edematous lungs. PEEP is often used to raise arterial oxygen tension in acute respiratory failure. This study was designed to answer the question: Does PEEP have an effect on the accuracy of the EVLW measurement by thermal dye? Sixteen mongrel dogs were anesthetized and intubated. Arterial and PA catheters were placed. They were divided into three groups and ventilated at PEEP levels of 5, 10, or 15 cm H2O. Fluids were given to minimize decrease in cardiac output with institution of PEEP. They were maintained for 5 hr with measurement of vital signs made hourly and measurement of blood gases and EVLW-TD made at baseline, 1, 3, and 5 hr. After final measurements, gravimetric determination of EVLW was done. Correlation between EVLWTD and EVLWGR remained good when low levels of PEEP were used. At 5 cm H2O PEEP, EVLWTD was 7.5 +/- 0.9 and EVLWGR was 5.4 +/- .3. At 10 cm H2O PEEP, they were 10.0 +/- 0.9 and 6.5 +/- 0.3. The correlations were 0.87 and 0.97, respectively. However, at 15 cm H2O PEEP, EVLWTD was 11.4 +/- 1.3 and EVLWGR was 7.5 +/- 0.6, with a correlation of only 0.59. The correlation between the two techniques seems to break down with higher levels of PEEP in dogs with normal lungs.

Reconstruction of silica exposure in the North Carolina dusty trades

The current occupational standard for quartz exposure is largely drawn from studies of the granite workers at Barre, Vermont. Since 1935, the North Carolina Dusty Trades program has accumulated data on work-place environmental conditions, occupational history and health status for persons exposed to silica in a broad range of mineral industries, including granite dimension stone. The environmental data have been collected with Greenburg-Smith and midget impingers and the respirable mass dust sampler. A procedure is presented to combine the results of these sampling methods and estimate exposure at the various jobs at each dusty trades plant. From an individual's occupational history, the environmental exposure estimates are used to formulate personal lifetime exposure summaries. The results of this procedure in the North Carolina granite industry compared well with historical data from Vermont granite sheds.

Ethanol activation of human natural cytotoxicity

Human lymphocytes cultured with ethanol and subsequently assayed for natural killer (NK) activity to K562 cells have enhanced NK activity compared to lymphocytes cultured without exposure to ethanol. Optimal enhancement occurred at 0.64% (v/v) ethanol, and required several hours of culture. Lymphocytes retained their enhanced cytolytic ability for several hours after removal from the ethanol-containing medium. The enhancement correlated with a faster rate of cytolysis by ethanol-treated lymphocytes, rather than recruitment of an increased number of killer cells, as measured with single cell assays. Inclusion of ethanol directly in the NK assays was inhibitory. Cells that had been cultured with ethanol were less sensitive to inhibition of NK activity by the proteinase substrate acetyl tyrosine ethyl ester than were control cells cultured without ethanol. Although this observation and the increased rate of cytolysis in the single cell assays are consistent with increased production of a chymotrypsin-like proteinase involved in cell-mediated cytotoxicity, no alteration in protein synthesis was detected concomitant with ethanol treatment. This report demonstrates that even without hepatic metabolism, ethanol can produce effects on lymphocyte function which remain after exposure to the reagent is discontinued.

Body burden of polychlorinated biphenyls among persons employed in capacitor manufacturing

In an effort to assess exposure among workers engaged in capacitors manufacture, PCB concentration was determined in plasma (290) and adipose tissue (61). In general, males had higher concentrations of PCBs than females. The correlation of plasma concentration (1-546 ppb) of the more highly chlorinated PCBs, which had been used in past, with total duration of employment suggested accumulation over time. The gc-ec pattern of these PCB peaks was, in most cases, characteristic of exposure to a PCB mixture with 54% chlorine. The less highly chlorinated PCBs, di-, tri-, and tetrachlorobiphenyls, were the source of current exposure, and were observed in concentrations of 6-2530 ppb in plasma. Higher exposure occurred among persons with direct contact with PCBs in jobs such as capacitor filling. Adipose tissue concentrations, for both the more highly chlorinated PCBs (1-165 ppm) and lower chlorinated PCBs (0.6-414 ppm), were proportional to those in plasma.

Decreased serum angiotensin converting enzyme in adult respiratory distress syndrome associated with sepsis: a preliminary report

Serum angiotensin converting enzyme (ACE) levels were obtained in 24 control patients who were critically ill, in 11 patients with cardiogenic pulmonary edema, in 8 patients with status postcardiopulmonary bypass, and in 12 patients with adult respiratory distress syndrome (ARDS). Mean values in cardiogenic pulmonary edema (24.3 +/- 3.9 SD) in cardiopulmonary bypass (19.5 +/- 3.1) and in patients with ARDS and no sepsis (n = 7, 19.0 +/- 5.5) were not significantly different from controls (20.7 +/- 2.8). In contrast, patients with ARDS and sepsis had markedly decreased serum ACE levels which fell outside of control range (n = 5, 8.6 +/- 2.3). The authors speculate that decreased ACE levels in the combination of sepsis and ARDS are due to the presence of circulating inhibitors of ACE. The finding of decreased serum ACE can be of potential clinical usefulness by raising the possibility of sepsis as the etiology of ARDS before results of blood cultures are available.

Asbestos in Vermont schools: findings of a statewide on-site investigation

Materials containing asbestos were found in 75 per cent of 336 Vermont Schools constructed or renovated between 1946 and 1974, with two-fifths of the materials in student exposure areas. Findings from visits to all schools contrasted with an earlier investigation relying on self-reporting. Of 105 schools with student exposure disclosed by the current survey, only eight had been identified in the earlier effort. Ceiling tiles, previously not believed to contain substantial asbestos material, constituted a source of student exposure in 36 schools.

Effect of testosterone and dibutyryl cAMP on the spontaneous maturation of pig oocytes

This study was undertaken to develop a system that simulated, to some extent, the environment of the immature follicle and which reversibly inhibited the spontaneous maturation of porcine oocytes. The hypothesis was tested that a physiological concentration of testosterone (0.5 microM) in the presence of the cyclic nucleotide derivative, dibutyryl cAMP (1 mM), would prevent germinal vesicle breakdown and subsequent chromatin condensation of intact oocytes. Liberated cumulus-enclosed (intact) and cumulus-free (denuded) oocytes were cultured in a complex serum-based medium supplemented with the steroid and/or the nucleotide analogue. After 24 h, chromatin spreads were prepared and meiotic maturation was scored. In the presence of testosterone or dibutyryl cAMP, meiotic maturation of intact oocytes was similarly and significantly inhibited (57 and 58% matured, respectively) compared with controls (74% matured). This inhibition, however, was not nearly as marked as when both compounds were present together (19% matured), indicating a synergistic inhibitory relationship between the steroid and nucleotide. The inhibition exerted by the two compounds on the intact oocyte was reversible, a finding consistent with the observation that fewer germinal vesicles were degenerate in 'inhibited' oocytes than in oocytes cultured in control, unsupplemented medium. Although maturation of denuded oocytes was likewise inhibited by testosterone + dibutyryl cAMP (15% matured compared with 68% in control medium), this inhibition was due to a direct action of the cAMP derivative on the oocyte, with testosterone playing a passive role. These results suggest, therefore, that the cumulus cell mediated the inhibitory action of testosterone and dibutyryl cAMP on the maturation of the intact oocyte. In the light of reports that FSH or cAMP stimulate aromatase activity in cultured granulosa cells, our results suggest that oestrogen may be implicated in the observed inhibition of oocyte maturation.

Blastocyst-endometrial interactions and protein synthesis during pre-implantation development in the pig studied in vitro

A co-culture technique is described for the study in vitro of interactions between elongated blastocyst tissue and endometrium in the pig. Culture conditions which were optimal for blastocyst protein synthesis were determined and tissue survival was assessed after 48 h in culture. A defined medium was adopted consisting of medium 199 supplemented with insulin and antibiotics. Blastocyst protein synthesis measured by labelled leucine incorporation was not enhanced by the addition of serum, suggesting either that it was not required for optimal protein synthesis ar that active substances of maternal (endometrial) origin were already adsorbed on to embryonic tissues. Endometrial explants co-cultured with blastocyst tissue enhanced blastocyst protein synthesis approximately fourfold when intrinsic protein synthesis was low, but had little effect if it was already high. Blastocyst explants in which protein synthesis was enhanced by co-culture with endometrium demonstrated an increased synthesis of prealbumin proteins with molecular weights of 25 000 to 30 000.