bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in sex steroid levels in yolks of the leghorn chicken, Gallus domesticus, during embryonic development
Authors: Elf Pamela K. , Fivizzani Albert J.
Published: October 2002

Yolk steroid hormones have been documented to have growth and behavior effects on hatchlings in several avian species. The purpose of these investigations was to determine initial levels of androstenedione (A), dihydrotestosterone (DHT), estradiol (E2), and testosterone (T), and document any changes in those hormones during the course of embryonic development in the Leghorn chicken, Gallus domesticus. Eggs were collected, labeled for hen of origin and egg sequence, incubated at 37.8°C, and sacrificed at predetermined times during development. The embryos were staged, the yolk material collected, homogenized and hormones extracted. A, DHT, E2, and T were separated via column chromatography and hormone levels determined using radioimmunoassays (RIAs). Results indicate a significant decrease in A and T during embryonic development, similar to that reported by our laboratory for the alligator, with A levels being significantly greater initially than levels of all other hormones. Changes in DHT mirrored changes in T levels. Chicken E2 yolk content dynamics differ from those we have measured in both the turtle and the alligator. After an initial decline, E2 in the yolks of chicken eggs undergoes a significant increase at the end of development, between embryonic stages 40 and 45 (days 14 and 20 of development). As the increase is much larger than could be accounted for by hormones present in the yolk material, this may represent early embryonic production of steroid hormones by the developing gonads. J. Exp. Zool. 293:594–600, 2002. © 2002 Wiley‐Liss, Inc.
Factors affecting the efficiency of somatic cell nuclear transplantation in the fish embryo
Authors: Liu Tong Ming , Yu Xiao Mu , Ye Yu Zhen , ZHOU Jian Feng , Wang Zhong Wei , Tong Jing Gou , Wu Ching Jiang
Published: October 2002

Procedures to improve somatic cell nuclear transplantation in fish were evaluated. We reported effects of nonirradiated recipient eggs, inactivated recipient eggs, different combinations between recipient eggs and donor cells, duration of serum starvation, generation number, and passage number of donor cells on developmental rates of nuclear transplant (NT) embryos. Exposure to 25,000 R of γ‐rays inactivated recipient eggs. Single nucleus of cultured, synchronized somatic cell from gynogenetic bighead carp (Aristichthys nobilis) was transplanted into nonirradiated or genetically inactivated unfertilized egg of gibel carp (Carassius auratus gibelio). There was no significant difference in developmental rate between nonirradiated and inactivated recipient eggs (27.27% vs. 25.71%, respectively). Chromosome count showed that 70.59% of NT embryos contained 48 chromosomes. It showed that most NT embryos came from donor nuclei of bighead carp, which was supported by microsatellite analysis of NT embryos. But 23.53% of NT embryos contained more than 48 chromosomes. It was presumed that those superfluous chromosomes came from nonirradiated recipient eggs. Besides, 5.88% of NT embryos were chimeras. Eggs of blunt‐snout bream (Megalobrama amblycephala) and gibel carp were better recipient eggs than those of loach (Misgurnus anguillicaudatus) (25% and 18.03% vs. 8.43%). Among different duration of serum starvation, developmental rate of NT embryos from somatic nuclei of three‐day serum starvation was the highest, reaching 25.71% compared to 14.14% (control), 20% (five‐day), and 21.95% (seven‐day). Cultured donor cells of less passage facilitated reprogramming of NT embryos than those of more passage. Recloning might improve the developmental rate of NT embryos from the differentiated donor nuclei. Developmental rate of fourth generation was the highest (54.83%) and the lowest for first generation (14.14%) compared to second generation (38.96%) and third generation (53.01%). J. Exp. Zool. 293:719–725, 2002. © 2002 Wiley‐Liss, Inc.
Purification and identification of a second form of vitellogenin from ascites of medaka (Oryzias latipes) treated with estrogen
Authors: Shimizu Munetaka , Fujiwara Yumi , Fukada Haruhisa , Hara Akihiko
Published: October 2002

Estrogen treatment of medaka leads to accumulation of ascites, in which vitellogenin (Vg) and choriogenins (precursors to vitelline envelope) are abundant. Besides those female‐specific proteins, we detected a new component in ascites that cross‐reacts with antiserum against egg yolk proteins. We tentatively named it egg yolk‐related protein (YRP). YRP was purified from ascites by hydroxylapatite chromatography followed by gel filtration. Purified YRP had a molecular mass of 460kDa in intact state while 570kDa for Vg. The molecular weight of purified YRP on SDS‐PAGE under both reducing and nonreducing conditions was 130kDa. YRP was confirmed to be a lipoglycophosphoprotein by staining with Sudan black, periodic acid‐Schiff (PAS) and methyl green. Amino acid composition of YRP resembled that of Vg except for a relatively low content of serine. A specific antiserum against YRP was raised in a rabbit. Antiserum against YRP specifically immunostained its antigen but not Vg or choriogenins. YRP was detected as a female‐specific protein in serum of breeding medaka. The antiserum also cross‐reacted with a band at 29kDa in egg extracts, which is not immunoreactive to antiserum against Vg. These data show that YRP is a precursor to some egg yolk proteins with differing antigenicity from Vg (Hamazaki et al. '87). We thus conclude that YRP is a second form of medaka Vg and rename YRP as Vg 2 while formerly reported Vg as Vg 1. J. Exp. Zool. 293:726–735, 2002. © 2002 Wiley‐Liss, Inc.
Tropomyosin isoforms present in the sea anemone, Anthopleura japonica (Anthozoa, Cnidaria)
Authors: Fujinoki Masakatsu , Tomiyama Toshiko , Ishimoda‐Takagi Tadashi
Published: October 2002

Five isoforms of tropomyosin, designated as TMa, TMb, TMc, TMd, and TMe, were detected in the sea anemone, Anthopleura japonica. The apparent molecular weights of these isoforms were estimated to be approximately 30kD to 37.5kD, and their pI values were approximately 4.55 (TMa and TMb) and 4.65 (TMc, TMd, and TMe). Although sea anemone tropomyosin isoforms have the ability to bind to rabbit skeletal muscle actin, they preferably bind to actin at higher concentrations of Mg2+ (10–20 mM) and slightly lower pH (6.2–7.2) than those used in conventional conditions. Antigenic properties of sea anemone tropomyosin seemed to be considerably specific to each isoform. Distribution of tropomyosin isoforms in the sea anemone body was somewhat portion‐specific. TMa, TMb, and TMe were detected similarly in the extracts from tentacle, oral disc, column, mouth, and pedal disc. Although TMc and TMd were detected abundantly in the tentacle extract and moderately in the column and mouth extracts, these components were not contained in the pedal disc extract and detected only faintly in the oral disc extract. J. Exp. Zool. 293:649–663, 2002. © 2002 Wiley‐Liss, Inc.
Identification of the 48‐kDa G11 protein from guinea pig testes as sperad
Authors: Ilayperuma Isurani
Published: October 2002

A protein found specifically in the membrane of spermatozoa called G11 has been implicated in sperm–egg binding and fusion. This study describes purification and identification of the G11 antigen. The G11 protein was purified using anion exchange chromatography, immunoaffinity chromatography and preparative SDS‐PAGE and was subjected to amino acid microsequencing by tandem mass spectrometry. Internal amino acid sequence data derived from the 48‐kDa G11 protein revealed that G11 is the recently discovered guinea pig sperm protein, sperad. Sperad is a transmembrane protein present in the periacrosomal plasma membrane of guinea pig sperm. The cytoplasmic domain of sperad was amplified from a guinea pig testes cDNA expression library by polymerase chain reaction and cloned into a prokaryotic gene expression vector, pGEX‐2T. The recombinant glutathione S‐transferase fusion protein was immunoblotted with monoclonal antibody G11. The results obtained from this study confirmed the monoclonal antibody G11 epitope location on the cytoplasmic domain of sperad. J. Exp. Zool. 293:617–623, 2002. © 2002 Wiley‐Liss, Inc.
Mechanical properties of the dorsal fin muscle of seahorse (Hippocampus) and pipefish (Syngnathus)
Authors: Ashley‐ross Miriam A.
Published: October 2002

The dorsal and pectoral fins are the primary locomotor organs in seahorses (Hippocampus) and pipefish (Syngnathus). The small dorsal fins beat at high oscillatory frequencies against the viscous medium of water. Both species are able to oscillate their fins at frequencies likely exceeding the point of flicker fusion for their predators, thus enhancing their ability to remain cryptic. High‐speed video demonstrated that seahorse dorsal fins beat at 30–42 Hz, while pipefish dorsal fins oscillate at 13–26 Hz. In both species, the movement of the fin is a sinusoidal wave that travels down the fin from anterior to posterior. Mechanical properties of seahorse and pipefish dorsal fin muscles were tested in vitro by the work loop method. Maximum isometric stress was 176.1 kN/m2 in seahorse and 111.5 kN/m2 in pipefish. Work and power output were examined at a series of frequencies encompassing the range observed in vivo, and at a number of strains (percent length change during a contractile cycle) within each frequency. At a given strain, work per cycle declined with increasing frequency, while power output rose to a maximum at an intermediate frequency and then declined. Frequency and strain interacted in a complex fashion; optimal strain was inversely related to cycle frequency over most of the frequency range tested. Seahorse dorsal fin muscle was able to generate positive work at higher cycling frequencies than pipefish. Both species produced positive work at higher frequencies than have been reported for axial and fin muscles from other fish. J. Exp. Zool. 293:561–577, 2002. © 2002 Wiley‐Liss, Inc.
Production of germline chimera in loach (Misgurnus anguillicaudatus) and proposal of new method for preservation of endangered fish species
Authors: Nakagawa Masahiro , Kobayashi Toru , Ueno Koichi
Published: October 2002

As part of the technique for preservation of endangered fish species, germline chimeras using the loach (Misgurnus anguillicaudatus) model were generated by embryonic cell manipulation. Transplanting cells from early‐stage embryos of a wild‐type strain to the blastoderm of an orange‐type strain generated chimeras. Within three days, many of the resulting individuals exhibited a dark pigment on several parts of their body, characteristic of the donor but not of the orange strain. At one year of age, four chimeras (one female and three males) were pair‐mated with the orange type, and F1 was obtained. One of the four F0 chimeras produced progeny similar to the wild type at a frequency of 0.24% (2/841). The results suggest that this method is a promising technique for the preservation of endangered fish species. J. Exp. Zool. 293:624–631, 2002. © 2002 Wiley‐Liss, Inc.
Multiple human chromosomes carrying tumor‐suppressor functions for the mouse melanoma cell line B16‐F10, identified by microcell‐mediated chromosome transfer
Authors: Kugoh Hiroyuki , Nakamoto Hiroko , Inoue Jun , Funaki Kenji , Barrett J. Carl , Oshimura Mitsuo
Published: October 2002

Many tumor‐suppressor genes are involved in the development and progression of cellular malignancy. To understand the functional role of tumor‐suppressor genes in melanoma and to identify the human chromosome that carries these genes, we transferred individually each normal human chromosome, except for the Y chromosome, into the mouse melanoma cell line B16‐F10, by microcell fusion. We examined the tumorigenicity of hybrid cells in nude mice and their in vitro growth properties. The introduction of human chromosomes 1 and 2 elicited a remarkable change in cell morphologic features, and cellular senescence was induced at seven to 10 population doublings. The growth rates of tumors derived from microcell hybrid clones containing introduced human chromosome 5, 7, 9, 10, 11, 13, 14, 15, 16, 19, 20, 21, 22, or X were significantly slower than that of the parental B16‐F10 cells, whereas the introduction of other human chromosomes had no effect on the tumorigenicity of these cells. The majority of microcell hybrid clones that exhibited suppressed tumorigenicity also showed a moderate reduction in doubling time compared with B16‐F10 cells. Microcell hybrid clones with an introduced human chromosome 5 showed complete suppression of in vitro–transformed phenotypes, including cell growth, saturation density, and colony‐forming efficiency in soft agar. Thus, these results indicated the presence of many cell senescence–related genes and putative tumor‐suppressor genes for the mouse melanoma cell line B16‐F10 and showed in vitro that many tumor‐suppressor genes control the phenotypes of transformed cells in the multistep process of neoplastic development. © 2002 Wiley‐Liss, Inc.
Epidemiology of herbal drugs use in Addis Ababa, Ethiopia
Authors: Gedif Teferi , Hahn Heinz‐Jurgen
Published: October 2002

Objective

To study the utilization patterns of herbal drug use in urban Ethiopia.

Methods

A cross‐sectional community‐based survey was conducted in Addis Ababa, capital city of Ethiopia, using a pre‐tested semi‐structured questionnaire. The questionnaire was administered to 600 heads of households, largely mothers, selected using a multi‐stage systematic random sampling technique, where the final sampling units were households.

Results

The prevalence of herbal drugs use was found to be 37%. The main reasons given for choosing herbal medicine as the first line medication option were: dissatisfaction with the services of modern health institutions due to their time consuming nature, cost considerations and perceived efficacy.

Conclusion

This study showed that in spite of the geographic accessibility of modern health institutions in urban areas, the use of traditional medicine, particularly herbal drugs, remains a major form of health care option. Hence health planners should give appropriate consideration to this sector. Copyright © 2002 John Wiley & Sons, Ltd.
Estrogen replacement therapy and risk of lung cancer
Authors: Blackman Janine A. , Coogan Patricia F. , Rosenberg Lynn , Strom Brian L. , Zauber Ann G. , Palmer Julie R. , Langenberg Patricia , Shapiro Samuel
Published: October 2002

Purpose

Some epidemiological data suggest that sex hormones may influence lung cancer risk, and estrogen receptors have been found in human non‐small cell lung tumors. We assessed the relation of the use of estrogen replacement therapy (ERT) to the risk of lung cancer in our hospital‐based Case–Control Surveillance Study, conducted in four US centers during 1976 to 2001.

Methods

Cases were 662 women aged 40 through 74 years with lung cancer and controls were 4671 women admitted for conditions unrelated to ERT use. We used multivariate unconditional logistic regression models to estimate odds ratios (OR) and 95% confidence intervals (CI) for ERT use for at least 3 months compared to no use or use for less than 3 months.

Results

The OR for lung cancer among ERT users was 1.0 (95%CI 0.8–1.4), and it was 1.0 (95%CI 0.7–1.4) among users of conjugated estrogens only. Risk did not increase as the duration of use increased. Odds ratios for specific lung cancer cell types were not significantly increased or decreased for use of ERT or conjugated estrogens. There were non‐significant increases for non‐small cell types other than squamous, but there was no consistent pattern across duration of use.

Conclusion

Our data do not support an increased risk of lung cancer among women who use ERT. Copyright © 2002 John Wiley & Sons, Ltd.
The nature and frequency of potential warfarin drug interactions that increase the risk of bleeding in patients with atrial fibrillation
Authors: Howard Patricia A. , Ellerbeck Edward F. , Engelman Kimberly K. , Patterson Kelly L.
Published: October 2002

Purpose

To determine the frequency with which atrial fibrillation (AF) patients receiving warfarin are prescribed interacting drugs that could increase bleeding risks.

Methods

We retrospectively examined medical records for 704 Medicare beneficiaries ≥65 years of age discharged from Kansas hospitals with AF. We identified all patients receiving warfarin and examined discharge prescriptions for drugs that could increase bleeding risk either by increasing the international normalized ratio (INR) or directly inhibiting hemostasis.

Results

Of 256 patients discharged on warfarin, 138 (54%) were prescribed another medication that could increase bleeding risk. Among these patients, 106 (41%) were discharged with a total of 150 prescriptions for drugs that could interact with warfarin to increase the INR. Antibiotics accounted for 67% of these prescriptions. Fifty‐three patients (21%) received 56 prescriptions for drugs which could inhibit hemostasis. These were primarily antiplatelet drugs with 61% of the prescriptions for aspirin. Patients with coronary artery disease were more likely than others to be prescribed warfarin plus antiplatelet agents (OR=2.80; p=0.04). More than one interacting drug was prescribed for 20% of the patients.

Conclusions

AF patients discharged on warfarin were frequently prescribed concomitant medications that increase bleeding risks. These patients should be closely monitored and counseled to watch for signs of bleeding. Copyright © 2002 John Wiley & Sons, Ltd.
Carbene polymerization: characterization of poly(carballyloxycarbene)
Authors: Liu Lijian , Song Ying , Li Hao
Published: October 2002

A polymer (Mw3000 g mol−1 with Mw/Mn 1.2) was obtained by the copper‐catalyzed nitrogen‐elimination of allyl diazoacetate. Its structure was determined as poly(carballyloxycarbene) (PCACB) by 1H and 13C NMR and IR spectroscopy.

© 2002 Society of Chemical Industry
Polymers with benzofuro‐benzofuran structures
Authors: Pourabas Behzad , Banihashemi Ahmad
Published: October 2002

Several kinds of molecules and also polymers are going to be discussed in the present article. Common feature in these molecules and polymers is the possessing of a specific structural part, namely benzofuro–benzofuran. This structure will appear in several molecules and kinds of polymers in the text. A condensation reaction between glyoxal and phenols is the reaction needed to produce the mentioned structural part, ie benzofuro–benzofuran. Because of the importance of this reaction, a brief historical background in the initial section of the article, and some discussion on the structural assignment of the reaction product and the reaction mechanism is also given in sections later on. Types of polymers, which are discussed in this article, are mainly heat stable polymers including polyamide, poly(ether ketone sulfone), polybenzimidazole, poly(amide‐benzimidazole) and polyarylates. Polyester, polyhaydrezide and polymers with NLO property are the other kinds of the discussed polymers in the text with the benzofuro–benzofuran structure in their main chain. There is not any detailed procedure provided in the text about the synthesis of the molecules or even the polymers and the general procedures provided follow only the methodological purposes of the authors. Thermal properties of the polymers are discussed in the final section of the article with an attempt to provide a comparative argument in order to reach a relationship between structure and thermal properties.

© 2001 Society of Chemical Industry.
Formation of polyacrylate brushes on silica surfaces
Authors: Parvole J , Billon L , Montfort J P
Published: October 2002

We report the formation of polyacrylate (molten state polymers: Tg < room temperature) monolayers attached onto silica surfaces using covalently bonded initiators for radical‐chain polymerisation. In a first reaction step, the initiator is self‐assembled on the surface. In a subsequent reaction, the initiator is activated and the polymer formed in situ at the surface of the substrate with high grafting density (‘grafting from’ procedure). Moreover, the use of a living free radical process permits the molecular weight and polydispersity of the polymer chains to be controlled, and thus the polymer monolayer thickness also. We have also made a preliminary qualitative characterisation by X‐ray spectroscopy (XPS) and Fourier transformed infrared (FTIR) measurements.

© 2002 Society of Chemical Industry
Synthetic polyamines as vectors for gene delivery
Authors: Dubruel Peter , De Strycker Joost , Westbroek Philippe , Bracke Ken , Temmerman Eduard , Vandervoort Jo , Ludwig Annick , Schacht Etienne
Published: October 2002

We report the synthesis and physicochemical evaluation of a series of cationic polymethacrylates as vectors for gene delivery. Two different types of polymer have been synthesized: The first is a series of polymers containing tertiary amine, pyridine, imidazole and acid groups; the second is a series of polyamines containing poly(ethylene oxide) (PEO) blocks or grafts. The ability of the different polymers to condense DNA has been studied by agarose gel electrophoresis; all polymers are able to condense DNA, their ability to do so being dependent on their chemical composition and molecular weight. The particle size of the different polymer–DNA complexes formed has been measured by dynamic light scattering: complexes have a particle size of around 50 nm. A clear effect of the chemical composition of the polymers on the zeta potential of their complexes with DNA is evident.

© 2002 Society of Chemical Industry
Synthesis of poly{[(2‐oxo‐1,3‐dioxolan‐4‐yl)‐methyl vinyl ether]‐co‐acrylonitrile} and its miscibility with SAN
Authors: Ha Chang‐Sik , Yoo Gohyup , Park Dae‐Won , Jo Nam‐Ju , Lee Jin‐Kook , Cho Won‐Jei
Published: October 2002

In this work, a novel copolymer of (2‐oxo‐1,3‐dioxolan‐4‐yl)methyl vinyl ether (OVE) and acrylonitrile (AN) [poly(OVE‐co‐AN)] was synthesized from the reaction of CO2 with oxirane. The copolymer was also blended with poly(styrene‐co‐acrylonitrile) (SAN) in order to develop an integrated process for the catalytic conversion of CO2 to useful polymer materials. It was found from the optical clarity, thermal analysis and light‐scattering studies that the poly(OVE‐co‐AN)/SAN blends were miscible over the entire range of blend compositions. Thermally induced phase separation behaviour of the miscible blends was also investigated using an atomic force microscopy (AFM).

© 2002 Society of Chemical Industry
Structured degradable poly(ether) hydrogels based on linear bifunctional macromonomers
Authors: Naraghi Kaynoush , Sahli Nabahat , Belbachir Mohamed , Franta Emile , J Lutz Pierre
Published: October 2002

Hydrogels based on poly(ethylene oxide) (PEO) are suitable materials for numerous biomedical applications. Among the different ways to design such hydrogels, homopolymerization of bifunctional PEO macromonomers represents a promising approach. The present work discusses the extension of this crosslinking procedure to prepare degradable hydrogels. Poly(1,3‐dioxolane) (PDXL) hydrogels were synthesized directly in water (or in organic solvents) by free‐radical homopolymerization of α,ω‐methacryloyloxy PDXL macromonomers. They were investigated as gels swollen to equilibrium in THF CH2Cl2 or in water. In each case, the amount of extractable material, the extent of equilibrium swelling and the uniaxial compression modulus were determined. Nethertheless, PDXL chains contain acetal groups sensitive to acidic degradation. Hydrogels constituted of hydrophilic poly(ethylene oxide) (PEO) chains containing a short central PDXL block were obtained from α,ω‐methacryloyloxy PEO‐block‐1,3‐PDXL‐block‐PEO macromonomers. The variation of the mechanical properties of pure PDXL networks, when placed in acidic media, was followed by uniaxial compression modulus measurements.

© 2002 Society of Chemical Industry
Membrane with incorporated hydrophobic ligand for hydrophobic interaction with proteins: application to lipase adsorption
Authors: Bayramoğlu Gülay , Denizli Adil , Arıca M Yakup
Published: October 2002

In this study, phenylalanine as a hydrophobic ligand was covalently attached on a co‐monomer, methacryloyl chloride. Then, poly(2‐hydroxyethyl methacrylate‐co‐methacrylamido‐phenylalanine), poly(HEMA/MAPA), membranes were prepared by UV‐initiated photopolymerization of 2‐hydroxyethyl methacrylate and methacrylamido‐phenylalanine. The lipase adsorption of these poly(HEMA/MAPA) membranes was determined by changing the hydrophobic ligand density, pH, temperature and concentration of lipase in the adsorption medium. The lipase adsorption capacity of the membranes increased as the ligand density on the membrane surface increased. The non‐specific adsorption of lipase on the poly(2‐hydroxyethyl methacrylate) membranes was negligible (12 µg cm−2 of membrane). The adsorption phenomena appeared to follow a typical Langmuir isotherm. The maximum adsorption capacity (Qm) of the poly(HEMA/MAPA‐5) membrane for lipase was 215 µg cm−2 of membrane. The equilibrium constant (kd) value was 1.43 mg ml−1. The lipase could repeatedly be adsorbed and desorbed on the affinity membrane without any significant loss in the adsorption capacity of the membrane.

© 2002 Society of Chemical Industry
Degradable polymers in a living environment: where do you end up?
Authors: Vert Michel , Santos Isabelle Dos , Ponsart Stéphanie , Alauzet Nathalie , Morgat Jean‐Louis , Coudane Jean , Garreau Henri
Published: October 2002

The resistance of synthetic polymers to the action of living systems is becoming more and more problematic in certain domains in which they are used for a limited period of time before becoming waste. It is exemplified in surgery, pharmacology, agriculture and in the environment too. In these domains, time‐resistant polymeric wastes are less and less acceptable. From this viewpoint, sutures, bone fracture fixation devices, mulch films and packagings are comparable. Basically they should be eliminated after use. Post‐use biorecycling is regarded as a possible solution to some of the problems raised by the management of these polymeric wastes, regardless of the domain of application. This contribution aims to present simple and versatile methods with a potential to investigate the fate, and especially the bioassimilation, of the degradation by‐products of degradable or bio‐degradable polymers in complex living media such as the human body, a compost or the outdoor environment. Two versatile methods are presented that have been developed to radio‐label degradable and biodegradable artificial aliphatic polyesters by substituting some protons by tritium atoms. It is also shown that weighing a population of starved earthworms, allowed to be in contact with degradable or biodegradable polymer, is a worthwhile method to demonstrate that degradation by‐products are bioassimilated.

© 2002 Society of Chemical Industry
Production of polyether polyols using caesium as catalyst
Authors: de Lucas Antonio , Rodríguez Lourdes , Pérez‐Collado Mario , Sánchez Paula
Published: October 2002

An alternative catalyst to the traditional KOH was studied for preparation of polyols, having high molecular weight (about 6 000 g mol−1) and low unsaturation content. KOH catalyst is useful until the equivalent weight of the polyol reaches about 1 000 g mol−1, at which point an excess of allylic terminal unsaturation starts to develop. Polyols were synthesised using caesium and potassium hydroxide, at different temperatures and catalyst concentrations. Both the unsaturation content of the final polyol and the synthesis time decreased using caesium hydroxide instead of potassium hydroxide under the same synthesis conditions. The relationship to temperature and catalyst concentration was also studied. GPC analyses showed an additional small peak in the product, attributed to the allyl adduct, whose intensity was greater when potassium hydroxide was used as catalyst.

© 2002 Society of Chemical Industry
Synthesis of polyols by anionic polymerization: determination of kinetic parameters of propylene oxide polymerization using caesium and potassium alcoholates
Authors: de Lucas Antonio , Rodríguez Lourdes , Pérez‐Collado Mario , Sánchez Paula , Rodríguez Juan F
Published: October 2002

CsOH is investigated, as an alternative to the traditionally used KOH, for the preparation of glycerine initiated polyols. CsOH allows polyether–polyols with higher molecular weights and lower unsaturation contents, ie of better quality, to be obtained. CsOH also increases the reaction rate and permits reduction of the time needed to produce a batch of polyol. Polyols were synthesized using caesium and potassium hydroxide at different temperatures and initiator concentrations. Kinetic constants at different temperatures are determined and parameters of the Arrhenius equation calculated for each type of initiator. Reaction rates for caesium are higher than those of potassium and therefore permit a reduction in production times.

Copyright © 2002 Society of Chemical Industry
New advances in poly(ethylene terephthalate) polymerization and degradation
Authors: MacDonald W A
Published: October 2002

Poly(ethylene terephthalate) (PET) has wide acceptance for use in direct contact with food, can be recycled and can be depolymerized to its monomer constituents. Advances are continually being made to reduce the environmental ‘footprint’ that the polymer leaves. This paper discusses new advances in three specific areas, ie process developments, catalysis and polymer degradation, that address this issue.

© 2002 Society of Chemical Industry
Modification of poly(styrene‐co‐divinylbenzene) resin by grafting on an aluminium selective ligand
Authors: Boudenne Jean‐Luc , Boussetta Sabrina , Brach‐Papa Christophe , Branger Catherine , Margaillan André , Théraulaz Frédéric
Published: October 2002

For use in the solid‐phase extraction of aluminium, a poly(styrene‐co‐divinylbenzene) commercial resin (Amberlite® XAD‐4) was modified by grafting on salicylic acid. Anchorage of this ligand was achieved via a ketone bridge formed by Friedel–Crafts acylation. Because of the insolubility of the resin in common organic solvents, the synthesis scheme was optimized on the monomeric entity, benzoyl chloride, so that the purity of products could be assessed by common analytical techniques (gas chromatography–mass spectrometry (GC‐MS), NMR and FTIR) and the yields improved. NMR spectroscopy indicated that the Friedel–Crafts acylation was performed in the position para to the methoxy group. The synthesis scheme was then applied to the resin activated by an acid chloride function. Different steps of the modification were characterized by FTIR and pyrolysis–gas chromatography–mass spectrometry (Py‐GC‐MS). The aluminium complexing capacity of the modified resin was evaluated and presence of complexed aluminium on the surface of the resin was assessed by scanning electron microscopy (SEM) and FTIR.

© 2002 Society of Chemical Industry
Hepatic targeting of macromolecular MRI contrast agents
Authors: Yan Guo‐Ping , Zhuo Ren‐Xi , Xu Mian‐Yi , Zhang Xu , Li Li‐Yun , Liu Mai‐Li , Ye Chao‐Hui
Published: October 2002

Water‐soluble polyester ligands were synthesized by the polycondensation of diethylenetriaminepentaacetic dianhydride (DTPAA) with protected polyalcohol 3‐O‐benzyl‐glycerol (3‐O‐Bz‐GLYC), pentaerythritol monobenzaldehyde (S‐Bz‐PETO) and N‐benzyldiethanolamine (N‐Bz‐DEA), respectively, and the protecting groups were then removed by hydrogenation to give polyesters P(DTPA–GLYC), P(DTPA–PETO) and P(DTPA–DEA). In the same manner, by adding ethylene glycol (EG) monomer into the polymerization system, polyesters P(DTPA–GLYC–EG), P(DTPA–PETO–EG) and P(DTPA–DEA–EG) were also synthesized. Pyridoxamine was chosen as a liver‐targeting group and it was first chlorocarbonylated and then incorporated into polyesters. The polyester ligands containing pyridoxamine group thus prepared were further reacted with GdCl3 in water at room temperature to give the corresponding hepatic‐targeting polyester gadolinium complexes. These macromolecular ligands and their gadolinium complexes were characterized by 1H NMR, IR, UV and elementary analysis. Relaxivity studies showed that these polyester gadolinium complexes possess higher relaxation effectiveness than that of the clinically used small molecular gadolinium complex Gd‐DTPA. In vitro cytotoxicity assay demonstrated that these macromolecular ligands and their gadolinium complexes have low cytotoxicity to the human normal liver cells (L‐02). Magnetic resonance imaging of the liver in rats indicated that these polyester MRI contrast agents containing pyridoxamine group exhibit liver‐targeting property.

© 2002 Society of Chemical Industry
Monomers reactivity ratios of fluorinated acrylates–styrene copolymers
Authors: Saïdi Salima , Guittard Frédéric , Géribaldi Serge
Published: October 2002

Copolymerizations of styrene and 2‐F‐hexylethyl acrylate, 4‐F‐hexylbutyl acrylate and 6‐F‐hexylhexyl acrylate were conducted by free radical polymerization in acetonitrile at 80 °C using AIBN as initiator. The reactivity ratios of the three systems were determined by the Fineman–Ross and Kelen–Tüdos methods. Consequently, Q and e values have been calculated by the Alfrey and Price method. We found that the spacer length between the fluorinated chain and the ester function has no influence on the reactivity of our fluorinated monomers. Comparison of these results with those described in the literature for hydrocarbon homologous confirmed the reactivity scale.

© 2002 Society of Chemical Industry
Evaluation of antipyretic potential of Leucas lavandulaefolia (Labiatae) aerial part extract
Authors: Mukherjee Kakali , Saha B. P. , Mukherjee Pulok K.
Published: October 2002

Methanol extract of Leucas lavandulaefolia (LLFE) was subjected to antipyretic evaluation with yeast‐induced pyrexia in rats. A yeast suspension (10 mL/kg, s.c.) increased the rectal temperature 19 h after administration. The extract at doses of 100, 200, 400 mg/kg (i.p.) produced significant dose dependent lowering of body temperature in yeast‐provoked elevation of body temperature in rats. The antipyretic effect produced was comparable to that of a standard antipyretic drug, paracetamol. Copyright © 2002 John Wiley & Sons, Ltd.
Potential antiamoebic property of the roots of Piper longum Linn.
Authors: Ghoshal Sheela , Lakshmi V.
Published: October 2002

In an earlier study we reported the effect of ethanol extracts of Piper longum fruit against caecal amoebiasis in rats. A follow‐up study to determine whether the roots possess similar antiamoebic activity was carried out. The ethanolic extract of roots was amoebicidal at 1000 μg/mL in vitro and cured 88% of caecal amoebiasis cases, suggesting that both the root and fruit of P. longum possess antiamoebic activity to approximately the same extent. Copyright © 2002 John Wiley & Sons, Ltd.
Antimalarial activity of extracts and alkaloids isolated from six plants used in traditional medicine in Mali and Sao Tome
Authors: Ancolio C. , Azas N. , Mahiou V. , Ollivier E. , Di Giorgio C. , Keita A. , Timon‐David P. , Balansard G.
Published: October 2002

Methanol and chloroform extracts were prepared from various parts of four plants collected in Mali: Guiera senegalensis (Gmel.) Combretaceae, Feretia apodanthera (Del.) Rubiaceae, Combretum micranthum (Don.) Combretaceae, Securidaca longepedunculata (Fres.) Polygalaceae and two plants ­collected in Sao Tome: Pycnanthus angolensis (Welw.) Myristicaceae and Morinda citrifolia (Benth.) Rubiaceae were assessed for their in vitro antimalarial activity and their cytotoxic effects on human monocytes (THP1 cells) by flow cytometry. The methanol extract of leaves of Feretia apodanthera and the chloroform extract of roots of Guiera senegalensis exhibited a pronounced antimalarial activity. Two alkaloids isolated from the active extract of Guiera senegalensis, harman and tetrahydroharman, showed antimalarial activity (IC50 lower than 4 μg/mL) and displayed low toxicity against THP1. Moreover, the decrease of THP1 cells in S phase of the cell cycle, after treatment with harman and tetrahydroharman, was probably due to an inhibition of total protein synthesis. Copyright © 2002 John Wiley & Sons, Ltd.
Effect of Artemisia santonicum L. on blood glucose in normal and alloxan‐induced diabetic rabbits
Authors: Korkmaz H. , Gürdal A.
Published: October 2002

The hypoglycaemic effect of panicles of Artemisia santonicum L. in normal and alloxan‐induced diabetic rabbits was investigated. Blood glucose levels were determined after oral administration of an aqueous extract of Artemisia santonicum L. In normal and diabetic rabbits, 2 mL/kg (0.42 g/kg) aqueous extract significantly (p < 0.01) reduced blood glucose levels 6 h after administration, which was consistent and time‐dependent. Copyright © 2002 John Wiley & Sons, Ltd.
Paramyxovirus strategies for evading the interferon response
Authors: Gotoh Bin , Komatsu Takayuki , Takeuchi Kenji , Yokoo Junko
Published: October 2002

Two genera, the Respirovirus (Sendai virus (SeV) and human parainfluenza virus (hPIV3) and the Rubulavirus (simian virus (SV) 5, SV41, mumps virus and hPIV2), of the three in the subfamily Paramyxovirinae inhibit interferon (IFN) signalling to circumvent the IFN response. The viral protein responsible for the inhibition is the C protein for respirovirus SeV and the V protein for the rubulaviruses, both of which are multifunctional accessory proteins expressed from the P gene. SeV suppresses IFN‐stimulated tyrosine phosphorylation of signal transducers and activators of transcription (STATs) at an early phase of infection and further inhibits the downstream signalling without degrading any of the signalling components in most cell lines. On the contrary, the Rubulavirus V protein targets Stat1 or Stat2 for degradation. Proteasome‐mediated degradation appears to be involved in most cases. Studies on the molecular mechanisms by which paramyxoviruses evade the IFN response will offer important information for modulating the JAK‐STAT pathway, designing novel antiviral drugs and recombinant live vaccines, and improving paramyxovirus expression vectors for gene therapy. Copyright © 2002 John Wiley & Sons, Ltd.
Molecular diagnosis of influenza
Authors: Ellis Joanna S. , Zambon Maria C.
Published: October 2002

The past decade has seen tremendous developments in molecular diagnostic techniques. In particular, the development of PCR technology has enabled rapid and sensitive viral diagnostic tests to influence patient management. Molecular methods used directly on clinical material have an important role to play in the diagnosis and surveillance of influenza viruses. Molecular diagnostic tests that allow timely and accurate detection of influenza are already implemented in many laboratories. The combination of automated purification of nucleic acids with real‐time PCR should enable even more rapid identification of viral pathogens such as influenza viruses in clinical material. The recent development of DNA microarrays to identify either multiple gene targets from a single pathogen, or multiple pathogens in a single sample has the capacity to transform influenza diagnosis. While molecular methods will not replace cell culture for the provision of virus isolates for antigenic characterisation, they remain invaluable in assisting our understanding of the epidemiology of influenza viruses. Copyright © 2002 John Wiley & Sons, Ltd.
The production of sustainable tourism: concepts and examples from Norway
Authors: Eligh Jason , Welford Richard , Ytterhus Bjarne
Published: October 2002

Place, location and locality are examined in the context of the development of tourism in a way that is consistent with the concept of sustainable development. Concepts relating to tourism destination management are discussed in this context and a number of characteristics indicating possible success factors are drawn out. Two examples from Norway are used to illustrate how successful destination management strategies can be applied and which of the success factors appear to be the most important. The paper suggests a very strong role for leadership, external funding, support from appropriate external agencies and the existence of consumer demand in an area where small size is more conducive to success. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment
Separating computation, coordination and configuration
Authors: Andrade L. , Fiadeiro J. L. , Gouveia J. , Koutsoukos G.
Published: October 2002

We present methodological and technological solutions for evolving large‐scale software systems. These solutions are based on many years of research and experience in developing systems in one of the most volatile application domains—banking. We discuss why ‘promising’ software development techniques, such as object‐oriented and component‐based approaches, on their own, cannot meet the challenges and objectives of software development today, and propose a three‐layered architectural approach based on the strict separation between computation, coordination and configuration. We present a set of modelling primitives, design principles and support tools through which such an approach can be put effectively into practice, and discuss how it promotes a more ‘dynamic’ approach to software evolution. Finally, we make comparisons with related work. Copyright © 2002 John Wiley & Sons, Ltd.
Evolving hypermedia systems: a layered software architecture
Authors: García‐Cabrera Lina , Rodríguez‐Fórtiz María José , Parets‐Llorca José
Published: October 2002

Hypermedia systems are evolutionary in nature. This paper presents SEM‐HP, a model based on a semantic, systemic and evolutionary perspective, which facilitates the management of hypermedia evolution during the whole lifecycle process. Following the model the architecture of hypermedia systems can be conceived as composed of three sub‐systems (conceptual, presentation and navigation) and two abstraction levels, the system level and the meta level (the first used by the reader and the second by the designer). The objective of this division is to achieve a good separation of concerns both in the development and in the evolution processes and to obtain a better understanding, thus facilitating the further development of tools. Copyright © 2002 John Wiley & Sons, Ltd.
Rapid functional analysis of protein–protein interactions by fluorescent C‐terminal labeling and single‐molecule imaging
Authors: Yamaguchi Junichi , Nemoto Naoto , Sasaki Toru , Tokumasu Ako , Mimori-Kiyosue Yuko , Yagi Toshiki , Funatsu Takashi
Published: October 2002

Detection of protein–protein interactions is a fundamental step to understanding gene function. Here we report a sensitive and rapid method for assaying protein–protein interactions at the single‐molecule level. Protein molecules were synthesized in a cell‐free translation system in the presence of Cy5‐puro, a fluorescent puromycin, using mRNA without a stop codon. The interaction of proteins thus prepared was visualized using a single‐molecule imaging technique. As a demonstration of this method, a motor protein, kinesin, was labeled with Cy5‐puro at an efficiency of about 90%, and the processive movement of kinesin along microtubules was observed by using total internal reflection microscopy. It took only 2 h from the synthesis of proteins to the functional analysis. This method is applicable to the functional analysis of various kinds of proteins.
Molecular cloning and disruption of a novel gene encoding UDP‐glucose:tetrahydrobiopterin α‐glucosyltransferase in the cyanobacterium Synechococcus sp. PCC 7942
Authors: Choi Yong Kee , Hwang Yoon Kyung , Park Young Shik
Published: October 2002

The gene encoding UDP‐glucose:tetrahydrobiopterin α‐glucosyltransferase (BGluT) was cloned from the genomic DNA of Synechococcus sp. PCC 7942. The encoded protein consisting of 359 amino acid residues was verified in vitro and in vivo to be responsible for the synthesis of tetrahydrobiopterin (BH4)‐glucoside produced in the organism. The BGluT gene is the first cloned in pteridine glycosyltransferases and also a novel one cloned so far in UDP‐glycosyltransferases. The mutant cells disrupted in the BGluT gene produced only aglycosidic BH4 at a level of 8.3% of the BH4‐glucoside in wild type cells and exhibited half of the wild type growth in normal photoautotrophic conditions. These results suggest that the glucosylation of BH4 is required for the maintenance of the high cellular concentration of the compound, thereby supporting the normal growth of Synechococcus sp. PCC 7942.
Identification of rod‐ and cone‐specific phosducins in teleost retinas
Authors: Kobayashi Yuko , Hisatomi Osamu , Satoh Takunori , Tokunaga Fumio
Published: October 2002

Phosducin (PD) is a regulatory protein of vertebrate phototransduction cascades. In mammalian retina, it has been thought that only one kind of PD commonly exists in both rods and cones. However, we have found two kinds of PD (OlPD‐R and OlPD‐C) in the retina of a teleost, medaka (Oryzias latipes). In situ hybridization and immunohistochemical analysis demonstrated that OlPD‐R and ‐C are selectively expressed in rods and cones, respectively. The antiserum against medaka PDs recognized two kinds of proteins in bluegill (Lepomis macrochirus) retina. These results suggest that rod‐ and cone‐specific PDs exist in teleost retinas, probably creating differences in light adaptation between rods and cones.
Activation of estrogen receptor β is a prerequisite for estrogen‐dependent upregulation of nitric oxide synthases in neonatal rat cardiac myocytes
Authors: Nuedling Simone , Karas Richard H. , Mendelsohn Michael E. , Katzenellenbogen John A. , Katzenellenbogen Benita S. , Meyer Rainer , Vetter Hans , Grohé Christian
Published: October 2002

Physiological effects of estrogen on myocardium are mediated by two intracellular estrogen receptors, ERα and ERβ, that regulate transcription of target genes through binding to specific DNA target sequences. To define the role of ERβ in the transcriptional activation of both endothelial (eNOS) and inducible nitric oxide synthase (iNOS) in cardiac myocytes, we used the complete ERβ‐specific antagonist R,R‐tetrahydrochrysene (R,R‐THC). R,R‐THC inhibited activation of iNOS/eNOS promoter‐luciferase reporter constructs (iNOS/eNOS‐Luc) in a dose‐dependent fashion in COS7 cells selectively transfected with ERβ, but failed to influence ERα‐mediated increase of iNOS/eNOS‐Luc. In neonatal rat cardiomyocytes transfected with eNOS‐Luc or iNOS‐Luc, incubation with 17β‐estradiol (E2, 10−8 M) for 24 h stimulated expression of eNOS and iNOS. R,R‐THC (10−5 M) completely inhibited this effect. Furthermore, eNOS and iNOS protein expression in cardiac myocytes induced by E2 was completely blocked by R,R‐THC as shown by immunoblot analysis. Taken together, these results show that ERβ mediates transcriptional activation of eNOS and iNOS by E2.
Infectious complications following abdominal hysterectomy in Karachi, Pakistan
Authors: Ahmed F. , Wasti S.
Published: October 2002

Objective: In this paper we studied the prevalence of post‐operative infections after total abdominal hysterectomy in Karachi, Pakistan and their associated risk factors. Method: A retrospective analysis was conducted by reviewing the case notes of 827 consecutive total abdominal hysterectomies. Results: The post‐operative infection rate was 22%. Of the patients, 6% (49) developed operative site infections including wound and vaginal cuff infections and pelvic abscesses while 16% (133) developed non‐operative site infections including urinary tract infections and thrombophlebitis. Six risk factors were found to be significantly associated with post‐operative infections: a pre‐operative hospitalization of more than 2 days (P<0.02); additional non‐gynecological procedures performed intra‐operatively (P<0.02); indwelling catheterization for more than 7 days (P<0.001); patient's age greater than 50 years (P<0.02); an underlying malignancy (P<0.0001); and developing a hematoma post‐operatively (P<0.04). Conclusion: The results of this study may serve as a baseline for future comparison and indicate interventions which may contribute to a reduction in the post‐operative infection rate.