Copper and cobalt in African species ofAeolanthus Mart. (Plectranthinae,Labiatae)

Summary Hyperaccumulators (here defined as species containing at least 500 μg/g dryweight of either copper or cobalt in leaves), are of interest for the fields of mineral exploration and phytochemistry. Reported hyperaccumulation of copper inAeolanthus biformifolius and the presence of two other species on copper/cobalt mineralization in Shaba (Za?re) led to a survey of these elements in 49 species of the African genusAeolanthus Mart.A. biformifolius appears to be also a hyperaccumulator of Co (2520 μg/g in leaves, 4300 μg/g in corms). Cobalt levels for most species ofAeolanthus were considerably above typical values for phanerogams and indicate the favorable potential of the genus for further study.     

Effects of substrate biodegradability on the mass and activity of the associated estuarine microbiota

Multiple biochemical assays of microbial mass and activities were applied to the estuarine detrital microbiota colonizing morphologically similar polyvinyl chloride needles and needles from slash pine (Pinus elliottii). Biodegradable pine needles consistently showed 2- to 10-fold higher values of extractable adenosine 5'-triphosphate, rates of oxygen utilization, activities of alkaline phosphatase and phosphodiesterase, and the mucopeptide cell wall component muramic acid than did the polyvinyl chloride needles, during a 14-week incubation in a semitropical estuary. The higher activities by the microbiota of the biodegradable substrate correlated with estimates of the microbial density from scanning electron microscopy. The microbial community associated with the nondegradable substrate showed minimal activity of beta-d-galactosidase, beta-d-glucosidase, and alpha-d-mannosidase in contrast to the biota of the degradable substrate, which showed 10- to 100-fold higher activities of these glycoesterases. These enzymes logically could be involved in catabolism of the carbohydrate polymers of the detritus. Assuming equivalent rates of predation, a surface that is also a utilizable substrate supports a three- to fivefold more active microbial population.     

Quantitative Microdialysis: Analysis of Transients and Application to Pharmacokinetics in Brain

The behavior of a microdialysis probe in vivo is mathematically described. A diffusion-reaction model is developed that not only accounts for transport of substances through tissues and probe membranes but also accounts for transport across the microvasculature and metabolism. Time-dependent equations are presented both for the effluent microdialysate concentration and for concentration profiles about the probe. The analysis applies either to measuring the tissue pharmacokinetics of drugs administered systemically, or for sampling of endogenously produced substances from tissue. In addition, an expression is developed for the transient concentration about the probe when it is used as an infusion device. All mathematical expressions are found to be a sum of an algebraic and an integral term. Theoretical prediction of time-dependent probe behavior in brain has been compared with experimental data for acetaminophen administered at 15 mg/kg to rats by intravenous bolus. Plasma and whole striatal tissue samples were used to describe plasma kinetics and to estimate a capillary permeability-area product of 0.07 min-1. Theoretical prediction of transient effluent dialysate concentrations exhibited close agreement with experimental data over 60 min. Terminal decline of the dialysate effluent concentration was slightly overestimated but theoretical concentrations still lay within the 95% confidence interval of the experimental data at 112 min. Microvasculature transport and metabolism play major roles in determining microdialysate transient responses. Extraction fraction (recovery) has been shown to be a declining function in time for five probe operating conditions. High rates of metabolism and/or capillary transport affect the time required to approach steady-state extraction, shortening the time as the rates increase. Conversely, for substances characterized by low permeabilities and negligible metabolism, experimental situations exist that are predicted to have very slow approaches to microdialysis steady state.     

Histochemical analysis of rat testicular glycoconjugates. 1. Subsets of N-linked saccharides in seminiferous tubules

Summary The distribution of N-linked glycans in rat testis has been probed using a panel of lectins derived fromGalanthus nivalis (snowdrop, GNA),Canavalia ensiformis (jack bean, Con A),Lens culinaris (lentil, LCA),Pisum sativum (garden pea, PSA) andPhaseolus vulgaris, erythro- and leucoagglutinins (kidney bean, ePHA and IPHA). Several classes of N-linked glycan were identified in the spermatogenic series, and during differentiation into spermatozoa they altered in both their pattern of distribution and relative abundance. A population of tetra-antennary, non-bisected, complex glycans, detected by IPHA, was lost during the transition from spermatogonia to spermatocytes, while high-mannose structures were acquired; these were most abundant in spermatocytes, as were bi- and tri-antennary complex, non-bisected glycans, the latter becoming increasingly abundant on acrosomes and spermatozoa. Their bisected counterparts were more generally expressed throughout spermatogenic cells, although marked localization onto acrosomes and nuclear caps was again seen. Transition from spermatocytes to spermatids involved mainly changes of the acrosomal granule and nuclear cap, which were carried through to the final stages of differentiation. Sertoli cell surfaces and cytoplasmic granules showed a high level of N-glycan expression.     

Histochemical analysis of rat testicular glycoconjugates. 2. Beta-galactosyl residues in O- and N-linked glycans in seminiferous tubules.

Summary Rat testes have been examined with a panel of lectins that bind specifically to oligosaccharide sequences having terminal or subterminal -galactosyl residues in O-linked glycans, or in the outer chains of complex N-linked glycans:Arachis hypogaea (peanut, AHA),Erythrina cristagalli (coral tree, ECA),Ricinus communis (castor bean, RCA120) andAbrus precatorius (jequirity bean, APA) agglutinins. Pretreatment of sections with neuraminidase, -galactosidase and removal of alkali-labile O-linked sequences by -elimination allowed the structure of these glycans to be further explored. In spermatogonia and spermatocytes there was little evidence of glycans terminating in -galactosyl residues, although these were present at non-reducing terminals as sialylgalactosides. The acrosome contained two subsets of O-linked glycans terminating in sialylgalactosides, while the nuclear cap showed at least two subsets of N-linked sialylgalactosyl as well as O-linked glycans. Spermatozoa exhibited minor changes in the pattern of glycosylation, although the overall pattern of -galactosyl expression was similar. Binding to Sertoli cells showed the presence of some unsubstituted -galactosyl terminals on O-linked glycans but few such N-linked residues, while terminal -galactosides were scanty in tubular basement membranes.     

Parathyroid hormone related protein and hypercalcaemia in breast cancer.

OBJECTIVE--To see whether parathyroid hormone related protein has a humoral role in breast cancer. DESIGN--Plasma concentrations and tumour expression of parathyroid hormone related protein were determined (by two site immunoradiometric assay and immunohistochemistry respectively) in women with breast cancer and related to the presence of bone metastases and serum calcium concentrations. SUBJECTS--Plasma concentrations of parathyroid hormone related protein were measured in 57 women with early breast cancer without apparent bone metastases, 28 women with bone metastases, and 13 women with bone metastases and hypercalcaemia. Tissue positivity for parathyroid hormone related protein was determined retrospectively in 106 primary breast tumours from women without apparent bone metastases and 72 tumours from women with bone metastases, 25 of whom subsequently developed hypercalcaemia. RESULTS--Plasma parathyroid hormone related protein concentrations were detectable (greater than 0.23 pmol/l) in 12 (92%) of the 13 hypercalcaemic patients with bone metastases compared with 10 (36%) of the 28 normocalcaemic patients with bone metastases and five (9%) of the 57 normocalcaemic patients without bone metastases. Parathyroid hormone related protein concentrations were significantly higher in hypercalcaemic than normocalcaemic patients with bone metastases. Tumour staining was positive for parathyroid hormone related protein in 22 (88%) of the 25 primary breast cancers from patients with bone metastases. Tumour staining was positive for parathyroid hormone related protein in 22 (88%) of the 25 primary breast cancers from patients with bone metastases who later developed hypercalcaemia compared with 25 (53%) of the 47 from women in this group who remained normocalcaemic and 55 (52%) of the 106 early breast cancers from women without known metastases. CONCLUSION--Tumour derived parathyroid hormone related protein may have an important humoral role in hypercalcaemia associated with metastatic breast cancer.     

The cincinnati lipid research clinic family study: Familial determinants of plasma uric acid

Summary Commingling analysis of plasma uric acid levels in a random sample of 160 nuclear families supports the hypothesis that there is a mixture of three distributions. Assuming one, two, and three components in the underlying distribution, we obtained the corresponding p-values (for power transformation) as 0.059, 1.040, and 1.643, respectively. Path analysis with p=0.059 gives genetic (h ²) and cultural (c ²) heritabilities as 0.256 and 0.199, without much support for intergenerational differences, assortative mating, or maternal effects. Complex segregation analysis with p=0.059 supports multifactorial inheritance, consistent with the findings of Gulbrandsen et al. (1979) and Morton (1979) in other populations. This study also fails to support a major locus hypothesis, contrary to earlier reports.This work was supported in part by N.I.H. and N.I.M.H. Grants GM 28719, and MH 31302, and by contract NO-1-HV-2-2914L from the National Heart, Lung, and blood Institute (Lipid Research Clinic's Program), General Clinical Research Center, and the CLINFO center Grant RR-00068-19     

ICR-191 and ethyl methanesulfonate induced mutagenesis at the immunoglobulin locus in the Y5606 cultured myeloma cell line

The Y5606 mouse tumor synthesizing an IgG3, lambda immunoglobulin (Ig) was adapted to continuous growth in tissue culture. The spontaneous mutation rate at the Ig locus (approximately 3 X 10(-5)/cell/generation) in this cell line was found to be less than that in other cultured mouse myeloma lines. Treatment with either ICR-191 or ethyl methanesulfonate (EMS) increased the mutation rate approx. 100-fold. Spontaneous and ICR-191 induced mutants were synthetic variants that is they synthesized either heavy (H) or light (L) chains alone instead of the H and L chains synthesized by the parent. Following EMS treatment assembly variants which were synthesizing structurally altered H chains were isolated in addition to synthetic variants. The assembly variants appear to be a unique consequence of EMS mutagenesis.     

The use of steady-state rate equations to analyse progress curve data.

Analysis of progress curves for enzyme-catalyzed reactions has been made by using a procedure that does not require the derivation of complex integrated rate equations. The method involves conversion of progress curve data to reaction velocities that are then fitted to the appropriate differential rate equation. Application of the procedure to data obtained for the reaction catalyzed by aspartate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1), showed that the resulting values for the kinetic parameters agreed well with those obtained by conventional progress curve analysis (Duggleby, R.G. and Morrison, J.F. (1978) Biochim. Biophys. Acta 526, 398--409).     

Parasitic infection of Filaroides osleri, Capillaria aerophila and Spirocera lupi in coyotes from the Southwestern United States

A total of 181 coyotes (Canis latrans) was examined for helminth parasites Filaroides osleri, Capillari aerophila, and Spirocerca lupi. Coyote carcasses were obtained from Kansas, western Oklahoma-northern Texas, Colorado, New Mexico, Arizona and southern California. Cysts of F. osleri were present in the trachea or bronchial division in 39 (22%) coyotes. C. aerophila were present in only 7 (4%) coyotes. S. lupi lesions were present in the aorta of 59 (33%) coyotes. Esophageal infections of S. lupi were found in only 4 of 142 (3%) coyotes. F. osleri, C. aerophila and S. lupi infections were more prevalent in western Oklahoma-northern Texas, low in southern Arizona-California, and absent in northern Arizona.