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Chañar (Geoffroea decorticans- Fabaceae) is a tree from South America that is normally infected with galls originated by insects. One of its parasites is Allodiplosis crassa (Cecidomyiidae, Diptera) which produces globular galls with sticky prolongations. Since this plant has medicinal uses in Argentina, its infestation could alter the quality of the plant drug. The surface of insect-induced galls usually contains defensive features such as trichomes, increased hardness and an increase in the content of polyphenolic compounds. The objective of this research is to assess the structural and histochemical features of the gall and to compare the content of polyphenolic metabolites in the gall, in the healthy leaf and in lignified stems of G. decorticans. The methanolic extract from the galls showed the highest amount of polyphenolic and proanthocyanidins and the lowest amount of hydroxycinnamic derivatives and flavonoids compared to the methanolic extract of the leaves. The photographs taken from the external surface of the gall showed that some prolongations have heads. The histochemical analysis showed that the prolongations have a high amount of proanthocyanidins and flavonoids; and that the heads are reactive to Sudan III. These phytochemical and histological characteristics may have a defensive role against harmful fungi and parasites that attack the larvae of the A. crassa. The results of this study show the presence of defensive features in an insect-induced gall of a medicinal plant with potential implications in the pharmacological activity of this species. This is the first report of a histochemical and phytochemical study in G. corticans galls. [ABSTRACT FROM AUTHOR]

Ligaria cuneifolia (R. et P.) Tiegh (Loranthaceae), known as liga, muérdago criollo, or Argentinean mistletoe, is a hemiparasitic plant with a broad distribution in central and northern Argentina. Pharmacological studies showed that L. cuneifolia extracts have hypolipemic, antioxidant, antibacterial, and immunomodulatory effects. We have established callus cultures from embryo and haustoria fragments. The highest frequency of callus formation from embryos (85%) was obtained on White medium with 4% (w/v) sucrose and 2.5 µM 1-naphtalene acetic acid and 9.2 µM kinetin as plant growth regulators (PGRs). From haustoria, the best result (35%) was obtained on Gamborg medium with 3% (w/v) sucrose and 0.45 µM 2,4-dichlorephenoxyacetic acid and 0.47 µM zeatin as PGRs. Thin layer chromatography showed that callus methanolic extract (2.5% w/v) had a lower content of flavonoids and proanthocyanins as compared to the wild plant (5% w/v for leaves, stems, and flowers), but a higher content of hydroxycinnamic acids. High performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) showed the presence of quercetin glycosides and phenolic acids in the methanolic extracts both from the parent plant and the callus obtained from embryo. Key message: Callus cultures were established from embryo and haustorium explants of Ligaria cuneifolia. Leaves, stems, and meristems were recalcitrant to in vitro culture. Callus tissues contained quercetin glycosides and phenolic acids. [ABSTRACT FROM AUTHOR]

A comprehensive second-generation whole genome radiation hybrid (RH II), cytogenetic and comparative map of the horse genome (2n = 64) has been developed using the 5000rad horse × hamster radiation hybrid panel and fluorescence in situ hybridization (FISH). The map contains 4,103 markers (3,816 RH; 1,144 FISH) assigned to all 31 pairs of autosomes and the X chromosome. The RH maps of individual chromosomes are anchored and oriented using 857 cytogenetic markers. The overall resolution of the map is one marker per 775 kilobase pairs (kb), which represents a more than five-fold improvement over the first-generation map. The RH II incorporates 920 markers shared jointly with the two recently reported meiotic maps. Consequently the two maps were aligned with the RH II maps of individual autosomes and the X chromosome. Additionally, a comparative map of the horse genome was generated by connecting 1,904 loci on the horse map with genome sequences available for eight diverse vertebrates to highlight regions of evolutionarily conserved syntenies, linkages, and chromosomal breakpoints. The integrated map thus obtained presents the most comprehensive information on the physical and comparative organization of the equine genome and will assist future assemblies of whole genome BAC fingerprint maps and the genome sequence. It will also serve as a tool to identify genes governing health, disease and performance traits in horses and assist us in understanding the evolution of the equine genome in relation to other species. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A comparative approach that utilizes information from more densely mapped or sequenced genomes is a proven and efficient means to increase our knowledge of the structure of the horse genome. Human chromosome 2 (HSA2), the second largest human chromosome, comprising 243 Mb, and containing 1246 known genes, corresponds to all or parts of three equine chromosomes. This report describes the assignment of 140 new markers (78 genes and 62 microsatellites) to the equine radiation hybrid (RH) map, and the anchoring of 24 of these markers to horse chromosomes by FISH. The updated equine RH maps for ECA6p, ECA15, and ECA18 resulting from this work have one, two, and three RH linkage groups, respectively, per chromosome/chromosome-arm. These maps have a three-fold increase in the number of mapped markers compared to previous maps of these chromosomes, and an increase in the average marker density to one marker per 1.3 Mb. Comparative maps of ECA6p, ECA15, and ECA18 with human, chimpanzee, dog, mouse, rat, and chicken genomes reveal blocks of conserved synteny across mammals and vertebrates. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Examines the radiation hybrid mapping of 63 previously unreported equine microsatellite loci. Digestion of horse genomic DNA with the restriction enzyme MboI, size selected by gel electrophoresis; Identification of clones containing a potential microsatellite; Development of primer pairs for polymerase chain reaction amplification of the markers.

This article cites a study on radiation hybrid mapping of 75 previously unreported equine microsatellite loci. Horse genomic DNA was digested with the restriction enzyme MboI, size selected by gel electrophoresis for fragments between 200 and 1200 bp and ligated into the BamHI site of the Ml 3 phage vector. Clones containing a potential microsatellite were identified by screening the library with [32P] 5' end-labelled oligo [dCA]16 and oligo [dGT]16 probes. The DNA was isolated from positive plaques and the inserts were sequenced using an ABI 3100 automated sequencer.

Mid-cervical kyphosis in diastrophic dysplasia (DD) with cord compression and weakness has been recognized for the last three decades. A strikingly similar situation exists in Larsen's syndrome (LS), an otherwise unrelated problem of weakness with lay joints and dislocations with typical facies. Forty patients with DD were studied of whom seven had cervical spine kyphosis: one patient had spontaneous correction over the ensuing two decades. Seven patients with LS were studied of whom four had cervical spine changes with cord compression. There was one sudden death among the patients with LS and no cases of spontaneous correction. Muscle weakness in DD and LS should lead to evaluation of cervical spine kyphosis with cord compression. Plain films, CT and recently MRI are useful. [ABSTRACT FROM AUTHOR]

The utilization of percutaneous injection of water-soluble iodide contrast media in evaluation of the position of the atretic rectal pouch in cases of imperforate anus is presented. This method demonstrates the exact site of atresia and often the origin of rectal fistulae. This method presents a more exact demonstration of an anatomic defect preparatory to surgery. [ABSTRACT FROM AUTHOR]