Spatial variability of different fractions of particulate matter within an urban environment and between urban and rural sites.

The spatial variability of different fractions of particulate matter (PM) was investigated in the city of Basel, Switzerland, based on measurements performed throughout 1997 with a mobile monitoring station at six sites and permanently recorded measurements from a fixed site. Additionally, PM10 measurements from the following year, which were concurrently recorded at two urban and two rural sites, were compared. Generally, the spatial variability of PM4, PM10, and total suspended particulates (TSP) within this Swiss urban environment (area = 36 km2) was rather limited. With the exception of one site in a street canyon next to a traffic light, traffic density had only a weak tendency to increase the levels of PM. Mean PM10 concentration at six sites with different traffic densities was in the range of less than +/- 10% of the mean urban PM10 level. However, comparing the mean PM levels on workdays to that on weekends indicated that the impact of human activities, including traffic, on ambient PM levels may be considerable. Differences in the daily PM10 concentrations between urban and more elevated rural sites were strongly influenced by the stability of the atmosphere. In summer, when no persistent surface inversions exist, differences between urban and rural sites were rather small. It can therefore be concluded that spatial variability of annual mean PM concentration between urban and rural sites in the Basel area may more likely be caused by varying altitude than by distance to the city center.

Studies on the metabolism and toxicological detection of the amphetamine-like anorectic fenproporex in human urine by gas chromatography-mass spectrometry and fluorescence polarization immunoassay.

Studies on the metabolism and the toxicological analysis of fenproporex (R,S-3-[(1-phenyl-2-propyl)-amino]-propionitrile, FP) using GC-MS and fluorescence polarization immunoassay are described. The metabolites were identified in urine samples of volunteers by GC-MS after cleavage of conjugates, extraction and acetylation. Besides unchanged FP, fourteen metabolites, including amphetamine, could be identified. Two partially overlapping metabolic pathways could be postulated: ring degradation by one- and two-fold aromatic hydroxylation followed by methylation and side chain degradation by N-dealkylation to amphetamine (AM). A minor pathway leads via beta-hydroxylation of AM to norephedrine. For GC-MS detection, the systematic toxicological analysis procedure including acid hydrolysis, extraction at pH 8-9 and acetylation was suitable (detection limits 50 ng/ml for FP and 100 ng/ml for AM). Excretion studies showed, that only AM but neither FP nor its specific metabolites were detectable 30-60 h after ingestion of 20 mg of FP. Therefore, misinterpretation can occur. The Abbott TDx FPIA amphetamine/methamphetamine II gave positive results up to 58 h. All the positive immunoassay results could be confirmed by the described GC-MS procedure.

Toward the behavioral health report card.

In this article, the authors review current organized efforts, strategies, and partnerships involved in attempts to design a behavioral health care report card that offers a comprehensive approach to obtaining performance measurements in the fields of psychiatry and chemical dependence treatment.

Considerations under capitated behavioral health care services.

A leading concern in the health care marketplace is the sharp cost increases associated with behavioral health care benefits over the past few years. Payers are desperately seeking alternative approaches for holding down managed behavioral health care costs and improving the quality of care. Many are focusing their attention on an integrated delivery system with capitated arrangements and direct contracting. The author discusses the requirements to succeed in this new delivery system.

Delayed maturation of the antibody response to type 2 thymus-independent antigens in a partially inbred strain of chicken.

The ontogeny of antibody responses to trinitrophenylated (TNP) thymus-independent (TI) antigens was compared in two partially inbred strains of chicken: the SC strain (B2/B2 genotype) and the FP strain (B15/B22 genotype). In the SC chicken, maturation of both the splenic anti-TNP plaque-forming cell (PFC) response and the 19S hemagglutinating antibody response to TI type 2 (TI-2) antigens, TNP-Ficoll and TNP-dextran, were delayed to a significantly later time in ontogeny (20 wk of age) than in the FP chickens (9 wk of age). Four- to 6-wk-old SC chickens were virtually immunologically unresponsive to stimulation with TI-2 antigens. The TI-1 antigen TNP-Brucella abortus was equally immunogenic in both FP and SC chickens of different age groups tested. Kinetic studies of the primary PFC response to TNP-Ficoll in immunologically mature chickens of the SC and FP strains demonstrated a peak PFC response 4 days after antigen injection, followed by a rapid decline in numbers of splenic PFC/spleen on day 6. The results of these studies are discussed in relation to earlier observations that suggested there may be a delay or a defect in the ontogeny of the thymus in the SC chicken.

Subpopulations of suppressor cells in chickens infected with cells of a transplantable lymphoblastic leukemia.

Three distinct subpopulations of cells with suppressor activity were separated by Ficoll density gradient centrifugation methods from the spleens of 3- to 4- week-old chickens infected with cultured lymphoblastoid cells (JM-VLC), derived from JM-V leukemia: (i) a subpopulation of nonadherent cells, which separated in the T-cell-rich gradient fraction of leukemic chicken spleen, inhibited proliferative responses to concanavalin A in mixed cultures with normal chicken spleen cells; (ii) phagocytic cells (macrophages), which were the most effective suppressor cells of all subpopulations in the mixed culture assay, were recovered among the cells of greatest density in the spleens of both normal and leukemic chickens; (iii) JM-VLC cells in the buoyant gradient fractions of leukemic chicken spleens also effected suppression. In the later stages of lymphoproliferative disease, the number of spleen cells of buoyant density was increased, apparently as a result of infiltration of the spleens with JM-VLC cells.

Sister chromatid exchange in Ph1-positive chronic myelocytic leukemia.

The sister chromatid exchange (SCE) frequency in bone-marrow cells of 12 untreated patients with chronic myelocytic leukemia (CML) was analysed and compared with the SCE frequency in bone-marrow cells of nine healthy persons. In normal persons the SCE ranged from 3.64 to 5.15 per cell. In CML patients the SCE was significantly lower, ranging from 2.32 to 3.44 per cell. The differences found were unrelated to patients' age and contraction state of the chromosomes. It is suggested that the leukemic process could account for the low SCE rate.

The rate of sister chromatid exchange in normal human bone marrow cells.

Sister chromatid exchange (SCE) was studied in bone marrow cells of six healthy individuals. Compared with peripheral blood lymphocytes, a remarkably low and constant rate of SCEs was observed, ranging from 3.64 to 4.65 per metaphase. The lower incidence of SCE can be related only partly to the higher contraction of bone marrow cells and the shorter exposure time to BUdR. Rather, a cell-specific phenomenon is suggested.

Density-gradient separation of spleen-cell subpopulations from Marek's disease virus-infected chickens.

Ficoll gradient separation of spleen-cell suspensions has shown that depressed T-cell mitogen reactivity in cultures of JM-VS and MD cells results from selective depletion of mitogen-responsive T-cells.

Effects of lymphocytes from Marek's disease-infected chickens on mitogen responses of syngeneic normal chicken spleen cells.

PHA responses have been measured in lymphoid cell cultures prepared by mixing normal chicken spleen cells with spleen or thymus cells from syngeneic chickens infected with the oncogenic herpesvirus MDV. Results of these studies may be summarized as follows: 1) spleen cells from MDV-infected chickens with visceral lymphomas inhibit the PHA response of normal spleen cells possibly by release of soluble inhibitory factors in response to the mitogen; 2) lymphoid cells from asymptomatic MDV-infected chickens, although hyporeactive themselves to PHA, can have a stimulatory effect on PHA responses of normal spleen cells in mixed cultures; 3) spleen cells from MDV-infected chickens, effectively protected from viral oncogenesis by HVT vaccination, show normal reactivity to PHA in spearate cultures and may react in mixed cultures like normal lymphocytes, with neither a pronounced stimulatory nor inhibitory effect on the PHA response of normal spleen cells.

Depression of in vitro responsiveness to phytohemagglutinin in spleen cells cultured from chickens with Marek's disease.

Cultures of dispersed spleen cells, prepared from MDV-infected chickens with MD visceral lymphomas, showed marked depression of responsiveness to the T cell mitogen PHA, as measured by 3H-Tdr incorporation in cells in vitro. When data are expressed quantitatively in terms of cpm/10(5) viable cells, the functional depletion of PHA-responsive cells appear to result from lower levels of 3H-Tdr incorporation in the PHA-stimulated spleen cultures from chickens with acute MD symptoms, as compared to similar cultures from uninfected isolator-reared control chickens. It is suggested that depression of PHA-induced blastogenesis is spleen cell cultures from chickens with acute MD reflects virus-related alterations in T lymphocytes.