Effects of phorbol myristate acetate on the synthesis of 5-oxo-6,8,11,14-eicosatetraenoic acid by human polymorphonuclear leukocytes.

5-Oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is a newly discovered chemotactic agent for human polymorphonuclear leukocytes (PMNL) which has potent stimulatory effects on cytosolic calcium levels in these cells. Although we have shown that it is synthesized from 5(S)-hydroxy-6,8,11,14-eicosatetraenoic acid (5-HETE) by a highly specific microsomal dehydrogenase, little is known about the synthesis of this substance by intact PMNL. In the present study we found that in contrast to PMNL microsomes, intact, unstimulated PMNL produced relatively small amounts of 5-oxo-ETE from 5-HETE, but instead converted 5-HETE primarily to its omega-oxidation product, 5,20-diHETE.

Expression of reducing sugar accumulation in interspecific somatic hybrids of potato.

A somatic hybridisation programme was undertaken to evaluate the expression of reducing sugar accumulation in potato. Interspecific hybrids created between the Solanum tuberosum cultivar Record and the diploid species Solanum phureja were evaluated at the morphological and molecular levels. These analyses indicated that the protoplast regenerants were partial (asymmetric) hybrids which had undergone elimination of S.

Detection of genetic diversity and selective gene introgression in coffee using RAPD markers.

RAPD (randomly amplified polymorphic DNA) markers generated by arbitary decamers have been successfully employed to detect genetic polymorphisms between coffee species and between Coffea arabica genotypes. The RAPD profiles were used to construct dendrograms and these were consistent with the known history and evolution of Coffea arabica. Material originating from Ethiopia and the arabica sub-groups - C.

Nascent RNA cleavage by arrested RNA polymerase II does not require upstream translocation of the elongation complex on DNA.

Obstacles incurred by RNA polymerase II during primary transcript synthesis have been identified in vivo and in vitro. Transcription past these impediments requires SII, an RNA polymerase II-binding protein. SII also activates a nuclease in arrested elongation complexes and this nascent RNA shortening precedes transcriptional readthrough.

Molecular mapping of genes determining height, time to heading, and growth habit in barley (Hordeum vulgare).

A combination of random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) markers has been used to locate genes controlling important developmental characters in barley. The denso dwarfing gene has been mapped to the long arm of chromosome 3H. Stepwise multiple regression was also used to identify another region of the barley genome (on chromosome 7H), which contributed to variation in height.

Identification of RAPD markers linked to genetic factors controlling the milling energy requirement of barley.

Doubled haploid (DH) populations of barley have been used in combination with PCR-based polymorphic-assay procedures to identify molecular markers linked to genes controlling the milling energy requirement of the grain. Milling energy (ME) is a quantitative trait and locating individual quantitative trait loci (QTLs) involved the construction of bulks by combining DNA from DH families representing the extreme members of the distribution for ME. In addition, the individuals had alternative alleles at theRrn2 locus that has previously been shown to be linked to an ME QTL.

Identification of RAPD markers linked to a Rhynchosporium secalis resistance locus in barley using near-isogenic lines and bulked segregant analysis.

Three hundred random sequence 10-mer primers were used to screen a pair of near-isogenic lines of barley and their donor parent for markers linked to genes conferring resistance to Rhynchosporium secalis. One primer was identified which reproducibly generated a product, SC10-65-H400, from the donor parent and the Rhynchosporium-resistant near-isogenic line but not from the recurrent parent. Segregation analysis on a barley doubled haploid population and examination of a further three near-isogenic lines, their donor and recurrent parents confirmed that this marker was linked to the Rhynchosporium resistance locus (Rh) on chromosome 3L.

Detection and analysis of genetic variation in Hordeum spontaneum populations from Israel using RAPD markers.

Randomly amplified polymorphic DNA (RAPD) markers were used to analyse genetic diversity within and between Hordeum spontaneum populations sampled from Israel. Nei's index of genetic differentiation was used to partition diversity into within and between population components. Fifty-seven per cent of the variation detected was partitioned within 10 H.

Stimulation of human neutrophils by 5-oxo-6,8,11,14-eicosatetraenoic acid by a mechanism independent of the leukotriene B4 receptor.

We recently identified a novel pathway for the metabolism of 5(S)-hydroxy-6,8,11,14-eicosatetraenoic acid (5-HETE) by human neutrophils, resulting in oxidation of the 5-hydroxyl group to give 5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) (Powell, W. S., Gravelle, F.

Genetic differentiation of cocoa (Theobroma cacao L.) populations revealed by RAPD analysis.

In order to preserve and exploit the valuable genetic resources of tropical forest trees, such as cocoa, a systematic assessment of the available genetic variability is necessary. The approach we have used is based on a simple mini-prep DNA extraction procedure together with a polymerase-chain-reaction- (PCR)-based polymorphic assay procedure (RAPD). Twenty-five cocoa accessions: IMCs and PAs collected from Peru and LCTEENs collected from Ecuador, which are difficult to distinguish using morphological or biochemical descriptors, were uniquely fingerprinted using a minimum of three oligonucleotide primers.

Taxonomic relationships between V. faba and its relatives based on nuclear and mitochondrial RFLPs and PCR analysis.

The taxonomic relationships between 52 accessions of 12 Vicia species and three accessions of Lathyrus were examined using nuclear RFLP- and PCR-generated data. Two hundred and sixty informative restriction fragments or amplification products were analysed by single linkage analysis, average cluster analysis, and the Wagner parsimony method. Dendrograms constructed from each type of analysis showed similar overall topologies and could be divided into three parts corresponding respectively to the Lathyrus outgroup, the species grouped in the section Faba/narbonemis complex, and the species belonging to the sections Hypechusa and Peregrinae.

Metabolism of 5(S)-hydroxyeicosanoids by a specific dehydrogenase in human neutrophils.

We have previously shown that human polymorphonuclear leukocytes (PMNL) convert 6-trans isomers of leukotriene B4 (LTB4) to 6,11-dihydro metabolites (Powell and Gravelle (1988) J. Biol. Chem.

Expression of the metalloproteinase matrilysin in DU-145 cells increases their invasive potential in severe combined immunodeficient mice.

Human prostate cancer displays a high degree of variability in its rate of spread, which could be due largely to differences in the invasive potential of the tumor cells. The degradation of the basal lamina and stromal extracellular matrix is mediated in part by the secretion of matrix metalloproteinases (MMPs). Matrilysin (PUMP-1, MMP-7) and gelatinase A (M(r) 72,000 type IV collagenase, MMP-2) have been shown to be overexpressed in prostate carcinoma.

Leukotrienes in bile during the early and the late airway responses after allergen challenge of sensitized rats.

The Brown Norway rat produces high levels of IgE in response to active immunization and develops both early and late airway constrictor responses after subsequent allergen challenge. We have used this model of allergic asthma to investigate the temporal relationship between the in vivo synthesis of peptidoleukotrienes (peptido-LTs) and the late response. Brown Norway rats that had been sensitized by injection of ovalbumin 2 to 3 wk prior to the commencement of the experiment were subjected to bile duct cannulation and tracheal intubation.

Transcription elongation by RNA polymerase II: mechanism of SII activation.

RNA chain elongation by RNA polymerase is a dynamic process. Techniques that allow the isolation of active elongation complexes have enabled investigators to describe individual steps in the polymerization of RNA chains. This article will describe recent studies of elongation by RNA polymerase II (pol II).

Prostate tumor cell invasion: a comparison of orthotopic and ectopic models.

Interest in orthotopic models has been generated by recent reports of increased invasive and metastatic potential demonstrated by tumor cell lines following injection into their tissue of origin rather than subcutaneously. We have previously demonstrated that transfection of the tumorigenic human prostate cell line, Du-145, with the metalloproteinase matrilysin increased its ability to invade the diaphragm following an intraperitoneal injection. In this study we compare the invasive and metastatic behavior of transfected Du-145 cell lines injected into the dorsal lateral lobe of the prostate to that observed when they are injected intraperitoneally.

Detection of genetic variation between and within populations of Gliricidia sepium and G. maculata using RAPD markers.

Gliricidia sepium and G. maculata are multi-purpose leguminous trees native to Central America and Mexico. Research programmes have been initiated to define the native distribution of Gliricidia and sample the spectrum of genetic variation.

Detection of polymorphic loci in Arachis germplasm using random amplified polymorphic DNAs.

The development of easily scoreable genetic markers in Arachis will facilitate the introgression of desirable traits from wild species into adapted germplasm. We have used random amplified polymorphic DNAs (RAPDs) to identify polymorphic molecular markers in a range of wild and cultivated Arachis species. From a total of sixty 10-mer oligonucleotide primers, 49 polymorphic loci were identified between cultivated A.

Metabolism of 5(S)-hydroxy-6,8,11,14-eicosatetraenoic acid and other 5(S)-hydroxyeicosanoids by a specific dehydrogenase in human polymorphonuclear leukocytes.

Human polymorphonuclear leukocytes (PMNL) convert 6-trans isomers of leukotriene B4 (LTB4) to dihydro metabolites (Powell, W.S., and Gravelle, F.

Understanding HCFA-2552-92 cost reporting forms.

The new cost reporting requirements necessitated by the new Medicare capital regulations may require up to 160 hours of additional data collection. Authors Powell and Pierce detail the anticipated changes to the Medicare cost reporting worksheets used to collect the data.

The use of RAPD markers for the detection of gene introgression in potato.

Randomly Amplified Polymorphic DNAs were employed to demonstrate that potato dihaploids generated after interspecific pollination of a tetraploid Solanum tuberosum cultivar (Pentland Crown) by Solanum phureja dihaploid inducer clones could not be of parthenogenetic origin. Of six different 10-mer oligonucleotides, four generated products from total potato dihaploid genomic DNAs which were not derived from the S. tuberosum parent.

Dexamethasone stimulates release of an ANP-like substance from rainbow trout cardiocytes.

A substance that cross-reacts with antiserum to human atrial natriuretic peptide (ANP) is found in fish hearts. This ANP-like material increases sodium output from the gill and kidney while inhibiting sodium uptake in the gut. Mammalian ANP secretion is stimulated by glucocorticoids, and cortisol injection increases sodium output in salt-loaded fish.

Down-regulation of cyclooxygenase product generation by human peritoneal macrophages.

Isolated human peritoneal macrophages under resting conditions synthesize and release significant quantities of the cyclooxygenase products prostaglandin E2 (PGE2) and thromboxane B2 (TXB2). These increased linearly with time and were dependent on de novo protein synthesis. Following the addition of calcium ionophore A23187 there was a marked decrease in total generation of immunoreactive cyclooxygenase products.

Grain isozyme and ribosomal DNA variability in Hordeum spontaneum populations from Israel.

Grain isozyme and ribosomal DNA (rDNA) variability was examined in Hordeum spontaneum populations sampled from 27 geographical sites in Israel. Considerable phenotypic variability was observed with variants of ADH1, EST3, EST10, BMY1 and WSP detected, which are not available in the H. vulgare gene pool.