Combined Review: Experiencing the New Genetics: Family and Kinship on the Medical Frontier and Born and Bred: Idioms and New Reproductive Technologies in England

Experiencing the New Genetics: Family and Kinship on the Medical Frontier. Kaja Finkler. Philadelphia: University of Pennsylvania Press, 2000. 296 pp.
Born and Bred: Idioms and New Reproductive Technologies in England. Jeanette Edwards. New York: Oxford University Press, 2000. 264 pp.     

Gene and domain duplication in the chordate Otx gene family: insights from amphioxus Otx

We report the genomic organization and deduced protein sequence of a cephalochordate member of the Otx homeobox gene family (AmphiOtx) and show its probable single-copy state in the genome. We also present molecular phylogenetic analysis indicating that there was single ancestral Otx gene in the first chordates which was duplicated in the vertebrate lineage after it had split from the lineage leading to the cephalochordates. Duplication of a C-terminal protein domain has occurred specifically in the vertebrate lineage, strengthening the case for a single Otx gene in an ancestral chordate whose gene structure has been retained in an extant cephalochordate. Comparative analysis of protein sequences and published gene expression patterns suggest that the ancestral chordate Otx gene had roles in patterning the anterior mesendoderm and central nervous system. These roles were elaborated following Otx gene duplication in vertebrates, accompanied by regulatory and structural divergence, particularly of Otx1 descendant genes.      

Electronic and resonance Raman spectra of iron(III) complexes of enterobactin, catechol, and N-methyl-2,3-dihydroxybenzamide.

Resonance Raman electronic absorption and circular dichroism spectra and pH titration curves are reported for the trianionic ferric complexes of enterobactin, catechol, and N-methyl-2,3-dihydroxybenzamide (MDHB). The spectral signatures of the enterobactin and MDHB complexes are virtually identical and differ from those of the catechol complex in ways that reflect the influence of the amide group on the electronic structure. Excitation in either the visible charge-transfer bands or the near-ultraviolet pi-pi* bands enhances Raman bands associated with benzene ring modes, although the relative enhancements differ markedly in the two regions. The data stronly support a structural model in which iron is bound exclusively to the phenolate oxygen atoms in all three complexes.     

The heavy metal ions Ag+ and Hg2+ trigger calcium release from cardiac sarcoplasmic reticulum

Heavy metal ions have been shown to induce Ca2+ release from skeletal sarcoplasmic reticulum (SR) by binding to free sulfhydryl groups on a Ca2+ channel protein and are now examined in cardiac SR. Ag+ and Hg2+ (at 10-25 microM) induced Ca2+ release from isolated canine cardiac SR vesicles whereas Ni2+, Cd2+, and Cu2+ had no effect at up to 200 microM. Ag(+)-induced Ca2+ release was measured in the presence of modulators of SR Ca2+ release was compared to Ca2(+)-induced Ca2+ release and was found to have the following characteristics. (i) Ag(+)-induced Ca2+ release was dependent on free [Mg2+], such that rates of efflux from actively loaded SR vesicles increased by 40% in 0.2 to 1.0 mM Mg2+ and decreased by 50% from 1.0 to 10.0 mM Mg2+. (ii) Ruthenium red (2-20 microM) and tetracaine (0.2-1.0 mM), known inhibitors of SR Ca2+ release, inhibited Ag(+)-induced Ca2+ release. (iii) Adenine nucleotides such as cAMP (0.25-2.0 mM) enhanced Ca2(+)-induced Ca2+ release, and stimulated Ag(+)-induced Ca2+ release. (iv) Low Ag+ to SR protein ratios (5-50 nmol Ag+/mg protein) stimulated Ca2(+)-dependent ATPase activity in Triton X-100-uncoupled SR vesicles. (v) At higher ratios of Ag+ to SR proteins (50-250 nmol Ag+/mg protein), the rate of Ca2+ efflux declined and Ca2(+)-dependent ATPase activity decreased gradually, up to a maximum of 50% inhibition. (vi) Ag+ stimulated Ca2+ efflux from passively loaded SR vesicles (i.e., in the absence of ATP and functional Ca2+ pumps), indicating a site of action distinct from the SR Ca2+ pump. Thus, at low Ag+ to SR protein ratios, Ag+ is very selective for the Ca2+ release channel. At higher ratios, this selectivity declines as Ag+ also inhibits the activity of Ca2+,Mg2(+)-ATPase pumps. Ag+ most likely binds to one or more sulfhydryl sites "on" or "adjacent" to the physiological Ca2+ release channel in cardiac SR to induce Ca2+ release.     

Synthesis and characterization of high-sensitivity Dy,Eu co-doped CaSO4 thermoluminescent phosphor using coprecipitation technique

In this work, (99 − x)CaSO₄-Dy₂O₃–xEu₂O₃, (where x = 0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5) thermoluminescence phosphors were prepared using a coprecipitation method. The thermoluminescence (TL) dosimetry (TLD) characteristics such as TL sensitivity, dose–response, minimum detectable dose, thermal fading, and the effect of sunlight on the prepared phosphors were investigated. The obtained results indicated that the most sensitive phosphor was obtained at x = 0.05. Large thermal fading of 6% after 1 h and 26% after 24 h from irradiation followed by 71% after 1 month with no additional fading was observed within a time frame exceeding 2 months throughout the remaining duration of the investigation, which also spanned over 2 months. Despite the phosphor's high fading rate, the relative sensitivity of the prepared samples was ~90% compared with TLD-100. The marked effect of day sunlight was also determined. High dose–response within the low-dose range from 0.01 to 5 Gy was observed. The obtained results suggested that the synthesized phosphor is well suited for applications involving radiation biology and radiotherapy dosimetry.     

A new test for measuring diapause in the pink bollworm Pectinophora gossypiella Sunders.

An ELISA test was developed to assay for the presence of a protein, pectinophorin, that is expressed only in diapausing last instar larvae of the pink bollworm, Pectinophora gossypiella Saunders. Use of the test provides a good estimation of the percent of diapause larvae in populations of pink bollworm in cotton fields in California and Arizona. All plow down dates are chosen before the majority of larvae enter diapause so as to eliminate as many overwintering survivors as possible. These dates may now be determined more precisely for any given field by use of the new ELISA procedure.     

Chemiluminescence determination of chlorpheniramine using tris(1,10‐phenanthroline)–ruthenium(II) peroxydisulphate system and sequential injection analysis

A sequential injection (SI) method was developed for the determination of chlorpheniramine (CPA), based on the reaction of this drug with tris(1,10‐phenanthroline)–ruthenium(II) [Ru(phen)₃²⁺] and peroxydisulphate (S₂O₈^2–) in the presence of light. The instrumental set‐up utilized a syringe pump and a multiposition valve to aspirate the reagents [Ru(phen)₃²⁺ and S₂O₈^2–] and a peristaltic pump to propel the sample. The experimental conditions affecting the chemiluminescence reaction were systematically optimized, using the univariate approach. Under the optimum conditions linear calibration curves of 0.1–10 µg/ml were obtained. The detection limit was 0.04 µg/ml and the relative standard deviation (RSD) was always < 5%. The procedure was applied to the analysis of CPA in pharmaceutical products and was found to be free from interferences from concomitants usually present in these preparations. Copyright © 2008 John Wiley & Sons, Ltd.