bluuebunny/crossref_metadata_2025 huggingface dataset:
Patch tests with thiurams at 0.25% pet. and 1% pet. are of equal diagnostic value
Authors: Geier Johannes , Frosch Peter J. , Schnuch Axel , Agathos Monika , Bauer Andrea , Brasch Jochen , Gaber Gisela , Gottlöber Petra , Grabbe Jürgen , Hartmann Martin , Jappe U. T. A. , Kaatz Martin , Lübbe Dieter , Pirker Claudia , Gefeller Olaf
Published: July 2002

Thiuram mix is tested in the standard series at a test concentration of 1% pet. The single thiurams (DPTD, TMTD, TMTM, TETD), however, are usually tested at 0.25% pet. in Germany. In other countries, the individual components of thiuram mix are tested at 1% pet. The German Contact Dermatitis Research Group (DKG) compared both patch test concentrations in 530 patients in order to find out if (i) a significant number of positive patch tests are missed by testing at the lower concentration, (ii) problems with irritant test reactions occur by increasing the test concentration to 1%, and (iii) the sensitivity of the thiuram mix rises when the breakdown test is done with the higher concentration. Slightly more positive reactions were seen with the higher concentration, but this increase did not reach statistical significance. The reaction index, as a measure for the relation of positive to irritant and/or questionable reactions, remained unchanged for the individual thiurams. The sensitivity of the mix also did not change when the breakdown test was performed with 1% pet. instead of 0.25% pet. Thus, we conclude that both concentrations are of equal diagnostic value in patch testing.
Progression of fibrosis in untreated patients with hepatitis C virus infection
Authors: Lagging L. Martin , Westin Johan , Svensson Elisabeth , Aires Nibia , Dhillon Amar P. , Lindh Magnus , Wejstål Rune , Norkrans Gunnar
Published: July 2002

Abstract: Background/Methods:In order to evaluate the progression of liver fibrosis associated with Hepatitis C virus (HCV) infection, two liver biopsy specimens obtained prior to antiviral therapy from 98 patients with HCV were scored and evaluated using statistical methods appropriate for ordered categorical data.

Results/conclusions:Greater progression of fibrosis was seen with increasing time between the biopsies. Likewise, the change in fibrosis score was significantly more pronounced in the 11 patients whose first biopsy was obtained within the first year after acquiring HCV. A multivariate logistic regression analysis of possible explanatory factors for the fibrosis outcome showed that interface hepatitis in both biopsies, the time interval between the biopsies, and age at first biopsy were associated with change in the fibrosis score. In addition we found that higher age at the time of infection was associated with development of cirrhosis, that moderate intake of alcohol was associated with fibrosis progression, and that an inflammatory response in the form of moderate interface hepatitis in the first biopsy was not necessarily associated with greater progression of fibrosis if the second biopsy showed mild interface hepatitis. However, having moderate interface hepatitis later in the course of infection as reflected by the second biopsy may be detrimental. If moderate interface hepatitis early in the course of the disease is followed by less interface hepatitis later there is less fibrosis; and if moderate interface hepatitis persists, there is more fibrosis eventually.
Integrin-linked kinase phosphorylates the myosin phosphatase target subunit at the inhibitory site in platelet cytoskeleton
Authors: KISS Enikö , MURÁNYI Andrea , CSORTOS Csilla , GERGELY Pál , ITO Masaaki , HARTSHORNE David J. , ERDÖDI Ferenc
Published: July 2002

The myosin phosphatase (MP) composed of the catalytic subunit of type 1 protein phosphatase and myosin phosphatase target subunit isoform 1 (MYPT1) was identified as the major serine/threonine phosphatase component in the platelet-cytoskeleton fraction. MYPT1 was phosphorylated by cytoskeletal kinase(s), but the identity of the kinase(s) and the effect of phosphorylation were not established. Incubation of platelet-cytoskeletal fraction with MgATP or MgATP[S] (magnesium adenosine 5′-[γ-thio]triphosphate) caused a decrease in the 20kDa light-chain of smooth-muscle myosin (MLC20) phosphatase and phosphorylase phosphatase activities. MYPT1 contains a phosphorylation site, Thr-695, involved in the inhibition of MP in a RhoA/Rho kinase-dependent manner. The cytoskeletal kinase(s) phosphorylated Thr-695 of glutathione S-transferase (GST)-MYPT1, as determined with an antibody specific for phosphorylated Thr-695. The level of Rho kinase was low in the cytoskeletal fraction and was detected primarily in the membrane and cytosolic fractions. The phosphorylation of Thr-695 by the cytoskeletal kinase(s) was not affected by Rho kinase inhibitor, Y-27632, suggesting that kinase(s) other than Rho kinase were involved. In-gel kinase assay identified a kinase at 54–59kDa that phosphorylated the C-terminal fragment of MYPT1 (GST-MYPT1667–1004). Western blots detected both zipper-interacting protein kinase (ZIPK) and integrin-linked kinase (ILK) at 54–59kDa in the cytoskeleton and membrane fractions. Cytoskeletal ZIPK and ILK were separated and partially purified by chromatography on SP-Sepharose and on MonoQ. ZIPK preferentially phosphorylated MLC20 and had low activity on MYPT1. ILK phosphorylated both MLC20 and MYPT1 and phosphorylation of MYPT1 occured on Thr-695. The above results raise the potential for regulation of MP activity in platelet cytoskeleton by ILK and suggest an alternative to the Rho-linked pathway.
Aerobic sn-glycerol-3-phosphate dehydrogenase from Escherichia coli binds to the cytoplasmic membrane through an amphipathic α-helix
Authors: WALZ Antje-Christine , DEMEL Rudy A. , de KRUIJFF Ben , MUTZEL Rupert
Published: July 2002

sn-Glycerol-3-phosphate dehydrogenase (GlpD) from Escherichia coli is a peripheral membrane enzyme involved in respiratory electron transfer. For it to display its enzymic activity, binding to the inner membrane is required. The way the enzyme interacts with the membrane and how this controls activity has not been elucidated. In the present study we provide evidence for direct protein—lipid interaction. Using the monolayer technique, we observed insertion of GlpD into lipid monolayers with a clear preference for anionic phospholipids. GlpD variants with point mutations in their predicted amphipathic helices showed a decreased ability to penetrate anionic phospholipid monolayers. From these data we propose that membrane binding of GlpD occurs by insertion of an amphipathic helix into the acyl-chain region of lipids mediated by negatively charged phospholipids.
XpsG, the major pseudopilin in Xanthomonas campestris pv. campestris, forms a pilus-like structure between cytoplasmic and outer membranes
Authors: HU Nien-Tai , LEU Wei-Ming , LEE Meng-Shiunn , CHEN Avon , CHEN Shu-Chung , SONG Yu-Ling , CHEN Ling-Yun
Published: July 2002

GspG, -H, -I, -J and -K proteins are members of the pseudopilin family. They are the components required for the type II secretion pathway, which translocates proteins across the outer membrane of Gram-negative bacteria to the extracellular milieu. They were predicted to form a pilus-like structure, and this has been shown for PulG of Klebsiella oxytoca by using electron microscopy. In the present study, we performed biochemical analyses of the XpsG protein of Xanthomonas campestris pv. campestris and observed that it is a pillar-like structure spanning the cytoplasmic and outer membranes. Subcellular fractionation revealed a soluble form (SF) of XpsG, in addition to the membrane form. Chromatographic analysis of SF XpsG in the absence of a detergent indicated that it is part of a large complex (>440kDa). In vitro studies indicated that XpsG is prone to aggregate in the absence of a detergent. We isolated and characterized a non-functional mutant defective in forming the large complex. It did not interfere with the function of wild-type XpsG and was not detectable in the SF. Moreover, unlike wild-type XpsG, which was distributed in both the cytoplasmic and outer membranes, it appeared only in the cytoplasmic membrane. When wild-type XpsG was co-expressed with His6-tagged XpsH but not with untagged XpsH, SF XpsG bound to nickel and co-eluted with XpsH. This result suggests the presence of other pseudopilin components in the XpsG-containing large-sized molecules.
The actin-severing activity of cofilin is exerted by the interplay of three distinct sites on cofilin and essential for cell viability
Authors: MORIYAMA Kenji , YAHARA Ichiro
Published: July 2002

Cofilin/actin-depolymerizing factor is an essential and conserved modulator of actin dynamics. Cofilin binds to actin in either monomeric or filamentous form, severs and depolymerizes actin filaments, and speeds up their treadmilling. A high turnover rate of F-actin in actin-based motility seems driven largely by cofilin-mediated acceleration of directional subunit release, but little by fragmentation of the filaments. On the other hand, the filament-severing function of cofilin seems relevant for the healthy growth of cells. In this study, we have characterized three mutants of porcine cofilin to elucidate the molecular mechanism that underlies the filament-severing activity of cofilin. The first mutant could neither associate with actin filaments nor sever them, whereas it effectively accelerated their treadmilling and directional subunit release. The second mutant bound to actin filaments, but failed to sever them and to interfere with phalloidin binding to the filament. The third mutant could associate with actin filaments and sever them, although with a very reduced efficacy. Of these mutant proteins, only the last one was able to rescue Δcof1 yeast cells and to induce thick actin bundles in mammalian cells upon overexpression. Therefore, the actin-severing activity of cofilin is an essential element in its vital function and suggested to be exerted by co-operation of at least three distinct sites of cofilin.
The cyclo-oxygenase-2 inhibitor celecoxib perturbs intracellular calcium by inhibiting endoplasmic reticulum Ca2+-ATPases: a plausible link with its anti-tumour effect and cardiovascular risks
Authors: JOHNSON Amy J. , HSU Ao-Lin , LIN Ho-Pi , SONG Xueqin , CHEN Ching-Shih
Published: July 2002

Substantial evidence indicates that the cyclo-oxygenase-2 (COX-2) inhibitor celecoxib, a widely prescribed anti-inflammatory agent, displays anti-tumour effect by sensitizing cancercells to apoptosis. As part of our effort to understand the mechanism by which celecoxib mediates apoptosis in androgen-independent prostate cancercells, we investigated its effect on intracellular calcium concentration ([Ca2+]i). Digital ratiometric imaging analysis indicates that exposure of PC-3cells to celecoxib stimulates an immediate [Ca2+]i rise in a dose- and time-dependent manner. Kinetic data show that this Ca2+ signal arises from internal Ca2+ release in conjunction with external Ca2+ influx. Examinations of the biochemical mechanism responsible for this Ca2+ mobilization indicate that celecoxib blocks endoplasmic reticulum (ER) Ca2+-ATPases. Consequently, inhibition of this Ca2+ reuptake mechanism results in Ca2+ mobilization from ER stores followed by capacitative calcium entry, leading to [Ca2+]i elevation. In view of the important role of Ca2+ in apoptosis regulation, this Ca2+ perturbation may represent part of the signalling mechanism that celecoxib uses to trigger rapid apoptotic death in cancercells. This Ca2+-ATPase inhibitory activity is highly specific for celecoxib, and is not noted with other COX inhibitors tested, including aspirin, ibuprofen, naproxen, rofecoxib (Vioxx®), DuP697 and NS398. Moreover, it is noteworthy that this activity is also observed in many other cell lines examined, including A7r5 smooth musclecells, NIH 3T3 fibroblastcells and Jurkat Tcells. Consequently, this Ca2+-perturbing effect may provide a plausible link with the reported toxicities of celecoxib such as increased cardiovascular risks in long-term anti-inflammatory therapy.
Calmodulin controls organization of the actin cytoskeleton via regulation of phosphatidylinositol (4,5)-bisphosphate synthesis in Saccharomyces cerevisiae
Authors: DESRIVIÈRES Sylvane , COOKE Frank T. , MORALES-JOHANSSON Helena , PARKER Peter J. , HALL Michael N.
Published: July 2002

Phosphoinositides regulate a wide range of cellular processes, including proliferation, survival, cytoskeleton remodelling and membrane trafficking, yet the mechanisms controlling the kinases, phosphatases and lipases that modulate phosphoinositide levels are poorly understood. In the present study, we describe a mechanism controlling MSS4, the sole phosphatidylinositol (4)-phosphate 5-kinase in Saccharomyces cerevisiae. Mutations in MSS4 and CMD1, encoding the small Ca2+-binding protein calmodulin, confer similar phenotypes, including loss of viability and defects in endocytosis and in organization of the actin cytoskeleton. Overexpression of MSS4 suppresses the growth and actin defects of cmd1-226, a temperature-sensitive calmodulin mutant which is defective in the organization of the actin cytoskeleton. Finally, the cmd1-226 mutant exhibits reduced levels of phosphatidylinositol (4,5)-bisphosphate. These findings suggest that calmodulin positively controls MSS4 activity and thereby the actin cytoskeleton.
Endoplasmic reticulum resident proteins of normal human dermal fibroblasts are the major targets for oxidative stress induced by hydrogen peroxide
Authors: VLIES Dennis van der , PAP Eward H.W. , POST Jan Andries , CELIS Julio E. , WIRTZ Karel W.A.
Published: July 2002

The membrane-permeable fluorescein-labelled tyramine conjugate (acetylTyrFluo) was used to identify the proteins of normal human dermal fibroblasts most susceptible to oxidation by hydrogen peroxide [Van der Vlies, Wirtz and Pap (2001) Biochemistry 40, 7783—7788]. By exposing the cells to H2O2 (0.1mM for 10min), TyrFluo was covalently linked to target proteins. TyrFluo-labelled and [35S]Met-labelled cell lysates were mixed and subjected to two-dimensional PAGE. After Western blotting the 35S-labelled proteins were visualized by autoradiography and the TyrFluo-labelled proteins by using anti-fluorescein antibody. The TyrFluo-labelled proteins were matched with the 35S-labelled proteins and identified by comparison with our mastermap of proteins. Protein disulphide isomerase (PDI), IgG-binding protein (BiP), calnexin, endoplasmin and glucose-regulated protein 58 (endoplasmic reticulum protein 57/GRP58) were identified as targets of oxidation. All these proteins reside in the endoplasmic reticulum and are part of the protein folding machinery. In agreement, confocal laser scanning microscopy showed co-localization of TyrFluo-labelled proteins and the KDEL receptor ERD-2, a marker for the endoplasmic reticulum.
Not much to ask for, really! The introduction of standard drink labelling in Australia
Authors: Hawks David
Published: July 2002

An account is provided of the processes leading up to the introduction of standard drink labelling on all alcoholic beverage containers in Australia. The roles of research and advocacy in recommending the introduction of such labelling are analysed as is the resistance of some parts of the alcohol beverage industry. It is concluded that the success of this policy initiative derived from the carefully orchestrated campaign in which researchers co‐operated with health advocates. The prior existence of nationally endorsed guidelines for safe drinking expressed in terms of standard drinks, recommendations of the National Health Policy on Alcohol and an accumulation of relevant research were crucial elements for success. However, the role played by some fortuitous circumstances cannot be ruled out.
Alpha‐smooth muscle actin expression in rat and mouse mesenteric wounds after transforming growth factor‐β1 treatment
Authors: Reza Ghassemifar M. , Schultz Gregory S. , Tarnuzzer Roy W. , Salerud Göran , Franzén Lennart E.
Published: July 2002

Rat mesenteric perforations heal by contraction within 5 to 7 days, whereas mouse mesenteric perforations seldom close within 3 weeks unless stimulated by transforming growth factor‐β1. In this article, we quantified the expression of alpha‐smooth muscle actin by quantitative‐reverse transcription‐polymerase chain reaction and the orientation of actin filaments at the wound margin by Fourier transformation image analysis after treatment with transforming growth factor‐β1. The expression of transforming growth factor‐β1 and its type II receptor was also assessed. Actin filaments were shown to increase with time at the wound margin in both species and the expression of alpha‐smooth muscle actin mRNA increased simultaneously. Transforming growth factor‐β1 enhanced the alpha‐smooth muscle actin expression four to five times in rats and three to four times in mice on day 5, but the number of copies expressed per cell was 15‐fold higher in rats than in mice. Transforming growth factor‐β1 was down‐regulated after wounding in free peritoneal cells of rats, but maintained until day 5 in transforming growth factor‐β1‐treated mice. The main finding of this study was that untreated, normal rats expressed substantially more alpha‐smooth muscle actin than mice. After treatment with transforming growth factor‐β1, this expression increased similarly in both species. It can be hypothesized that normal closure of mesenteric perforations requires a minimum level of actin expression. This level is not reached in normal mice, but is exceeded after stimulation. Perforations in the rat always close, because the alpha‐smooth muscle actin expression is always above this level.
Enhancement of wound healing by curcumin in animals
Authors: Sidhu Gurmel S. , Singh Anoop K. , Thaloor Deepa , Banaudha Krishna K. , Patnaik Gyanendra K. , Srimal Rikhab C. , Maheshwari Radha K.
Published: July 2002

Tissue repair and wound healing are complex processes that involve inflammation, granulation, and remodeling of the tissue. In this study, we evaluated the in vivo effects of curcumin (difeurloylmethane), a natural product obtained from the rhizomes of Curcuma longa on wound healing in rats and guinea pigs. We observed faster wound closure of punch wounds in curcumin‐treated animals in comparison with untreated controls. Biopsies of the wound showed reepithelialization of the epidermis and increased migration of various cells including myofibroblasts, fibroblasts, and macrophages in the wound bed. Multiple areas within the dermis showed extensive neovascularization, and Masson's Trichrome staining showed greater collagen deposition in curcumin‐treated wounds. Immunohistochemical localization of transforming growth factor‐β1 showed an increase in curcumin‐treated wounds as compared with untreated wounds. In situ hybridization and polymerase chain reaction analysis also showed an increase in the mRNA transcripts of transforming growth factor‐β1 and fibronectin in curcumin‐treated wounds. Because transforming growth factor‐β1 is known to enhance wound healing, it may be possible that transforming growth factor‐β1 plays an important role in the enhancement of wound healing by curcumin.
Collagen expression by novel cell populations in the dermal wound environment
Authors: Lindblad William J.
Published: July 2002

Numerous collagenous structures must be reconstituted following injury to the skin in order to return function to this tissue. The basement membrane zone, vascular basement membranes, and the dense connective tissue of the dermis are examples of structures that contain a number of different collagen types and that may need replacement following injury. In addition, a scar is deposited at the site of damage in order to substitute for elements lost in the trauma and for elements that cannot be successfully replaced. Clearly, cells resident within the different compartments of the skin are able to synthesize and deposit collagen to reform these multiple structures. However, accumulating experimental evidence suggests that in addition to these resident cells, blood‐borne cells may be responsible for the deposition of a portion of the newly synthesized collagen. Studies from this laboratory point to the activated monocyte as a potential source of collagen in the wound environment. Given the dynamics of the process, the hypothesis is proposed that during normal wound healing, the activated monocyte is a source of collagen essential for the rapid formation of a provisional matrix conducive for the subsequent formation of granulation tissue. Collagen synthesis also occurs by expanded populations of resident cells, under the influence of inflammatory cell‐derived mediators, which results in the major accumulation of collagen during normal wound repair. However, if a chronic inflammatory state is initiated, the activated monocytes may remain in sufficient numbers to deposit collagen leading to a pathological lesion.
Long‐term nonpassaged EGF‐responsive neural precursor cells are stem cells
Authors: Zhou Feng C. , Chiang Yung H.
Published: July 2002

We have screened lines of nonpassaged epidermal growth factor‐responsive neurospheres from embryonic striatum and brainstem. They have been maintained in defined medium with epidermal growth factor over a period of 2 years and remained in an undifferentiated state to this date. Since isolation from the brain 2 years ago, these nonpassaged epidermal growth factor responsive neurospheres have shown active proliferation and self‐renewal capacity. When subplated on a poly‐D‐lysine coated surface, they resumed differentiation within 24 hours. The differentiation process of the nonpassaged epidermal growth factor responsive neurosphere appeared to recapitulate the neural development in the brain. Many cells migrated, extending radial processes while expressing nestin and S100 in the early 7‐day subplating culture. They continued to differentiate into major neural types in 14‐day subplating culture, including fibrous and cytoplasmic astrocytes, oligodendrocytes, and serotonin, γ‐aminobutyric acid, and a small number of tyrosine hydroxylase‐positive neurons. The nonpassaged epidermal growth factor‐responsive neurospheres in many ways resemble hemopoietic cells. Both are proliferative, possess the potential of indefinite self‐renewal, yet multipotent, and are capable of resuming the differential pathway. The nonpassaged epidermal growth factor responsive neurospheres meet the criteria of stem cells and have been found to be a useful model to study the development in vitro.
Single local instillation of Staphylococcus aureus peptidoglycan prevents diabetes‐induced impaired wound healing
Authors: Qiu Jian G. , Chang Tsueng H. , Steinberg Jacob J. , Levenson Stanley M.
Published: July 2002

Diabetes‐induced impaired wound healing is characterized by inhibition of the inflammatory response to wounding, macrophage infiltration, angiogenesis, fibroplasia, reparative collagen accumulation, and wound breaking strength. Because all of these processes are accelerated in normal rats by a single local application at operation of Staphylococcus aureus peptidoglycan, we hypothesized that S. aureus peptidoglycan would prevent diabetes‐induced impaired wound healing, despite persistent, untreated hyperglycemia, polydipsia, glycosuria, and polyuria. Sprague‐Dawley male rats were divided into two groups. One group received an intraperitoneal injection of streptozotocin (65 mg/kg) in citrate solution; the other group received an intraperitoneal injection of an equivalent volume of citrate solution. Seventeen days after the injections, the diabetic and control rats received aseptically two 5.5‐cm paravertebral incisions and subcutaneous implantation of six polyvinyl alcohol sponges, three on each side. On one side, each sponge contained 0.5 mg S. aureus peptidoglycan in 50 µl saline solution, and the incision was inoculated along its length with 4.7 mg S. aureus peptidoglycan in 157 µl saline solution (860 µg/S. aureus peptidoglycan/cm incision); on the other side, the same respective volumes of saline were used. During the preoperative and postoperative periods, diabetic rats lost a small amount of weight (2%), were hyperglycemic (363 ± 10 mg/100 ml blood), polydipsic, glycosuric, and polyuric, whereas the controls gained weight (25%) and were normoglycemic (104 ± 5 mg/100 ml blood); these differences were significantly different (p < .001 in each case). In controls, S. aureus peptidoglycan inoculation increased wound breaking strength (by a factor of 2.0) and hydroxyproline content (by a factor of 1.4; p < .001 in each case); in diabetics, there were significant decreases in wound breaking strength (by a factor of 1.7) and hydroxyproline content (by a factor of 1.3) of saline solution‐inoculated incisions and sponges compared with the wound breaking strength and hydroxyproline content of saline solution‐inoculated incisions and sponges in controls (p < .02 and p < .001, respectively). These decreases were completely prevented when the incisions and polyvinyl alcohol sponges had been inoculated at operation with S. aureus peptidoglycan; S. aureus peptidoglycan inoculation in the diabetic rats increased wound breaking strength by a factor of 2.2 and sponge reparative tissue hydroxyproline by a factor of 1.6 (p < .001 in each case). Thus, diabetes‐induced impaired wound healing was prevented completely by a single local instillation at operation of S. aureus peptidoglycan, despite persistent, untreated hyperglycemia, polydipsia, polyuria, and glycosuria.
Isolation, characterization, and family study of DTI, a novel partial D phenotype affecting the fourth external loop of D polypeptides
Authors: Omi Toshinori , Takahashi Junko , Seno Taiko , Tanaka Mitsunobu , Hirayama Fumiya , Matsuo Michie , Ueda Naoki , Obara Kenryo , Okuda Hiroshi , Iwamoto Sadahiko , Tani Yoshihiko , Kajii Eiji
Published: July 2002

BACKGROUND: The Rh system is the most polymorphic of the blood group systems and is of major importance in transfusion medicine. The partial D phenotypes lack one or more of the D epitopes. These variants appear to have arisen through hybrid RhD‐CE‐D or by spontaneous point mutations in RhD. The serologic findings and the molecular characterization of a novel partial D phenotype, termed DTI, are presented here.

STUDY DESIGN AND METHODS: RBCs from the DTI proband and RBCs from individuals with other partial D phenotypes were tested with MoAbs against 16 D epi‐ topes, according to the recommendations of the 4th ISBT Workshop on MoAbs (Rh Section 1A). A full‐length cDNA encoding DTI and introns 4 and 5 of RhD were isolated and analyzed by DNA sequencing. A family study of the DTI allele was carried out using PCR‐RFLP and long‐range PCR methods.

RESULTS: Analysis of RBCs from the proband revealed that the DTI phenotype lacks epitopes D1, D2.1 (partial), D2.2, D5, D6 (partial), and D8. The DTI polypeptide exhibits seven amino acid substitutions in the D polypeptide: F223V, A226P, E233Q, V238M, V245L, G263R, and K267M. The genomic organization of DTI showed that the replacement of RhD with RhCE was located in intron 4, and the replacement of RhCE with RhD was located in intron 5. Family studies revealed that the DTI allele was inherited maternally, whereas the RhD− allele was inherited paternally in the proband.

CONCLUSION: The serologic data provide the first molecular characterization of DTI, a previously unknown partial D phenotype. This phenotype affected the D polypeptide within the fourth external loop, resulting in a new RhD‐CE (entire exon 5)‐D hybrid gene. It is worth noting that P226, encoded by exon 5, is derived from E of RhCE in the DTI polypeptide. Family studies demonstrated that DTI was associated with a cDTIE haplotype.
Embryonic Arrhythmia by Inhibition of HERG Channels: A Common Hypoxia‐related Teratogenic Mechanism for Antiepileptic Drugs?
Authors: Azarbayjani Faranak , Danielsson Bengt R.
Published: July 2002

Summary:  Purpose: There is evidence that drug‐induced embryonic arrhythmia initiates phenytoin (PHT) teratogenicity. The arrhythmia, which links to the potential of PHT to inhibit a specific potassium channel (Ikr), may result in episodes of embryonic ischemia and generation of reactive oxygen species (ROS) at reperfusion. This study sought to determine whether the proposed mechanism might be relevant for the teratogenic antiepileptic drug trimethadione (TMO).

Methods: Effects on embryonic heart rhythm during various stages of organogenesis were examined in CD‐1 mice after maternal administration (125–1,000 mg/kg) of dimethadione (DMO), the pharmacologically active metabolite of TMO. Palatal development was examined after administration of a teratogenic dose of DMO and after simultaneous treatment with DMO and a ROS‐capturing agent (α‐phenyl‐N‐tert‐butyl‐nitrone; PBN). The Ikr blocking potentials of TMO and DMO were investigated in HERG‐transfected cells by using voltage patch‐clamping tests.

Results: DMO caused stage‐specific (gestation days 9–13 only) and dose‐dependent embryonic bradycardia and arrhythmia at clinically relevant maternal plasma concentrations (3–11 mM). Hemorrhage in the nasopharyngeal part of the embryonic palate (within 24 h) preceded cleft palate in fetuses at term. Simultaneous treatment with PBN significantly reduced the incidence of DMO‐induced cleft palate, from 40 to 13%. Voltage patch‐clamping studies showed that particularly DMO (70% inhibition), but also TMO, had Ikr blocking potential at clinically relevant concentrations.

Conclusions: TMO teratogenicity, in the same way as previously shown for PHT, was associated with Ikr‐mediated episodes of embryonic cardiac arrhythmia and hypoxia/reoxygenation damage.
Club‐Shaped Organs as Additional Osmophores within theSauromatumInflorescence: Odour Analysis, Ultrastructural Changes and Pollination Aspects4
Authors: Hadacek F. , Weber M.
Published: July 2002

Abstract:Gradient odour emissions in the inflorescence of the AraceaeSauromatum guttatumaim to attract a wide range of insects into the floral chamber. The volatiles are emitted from the spadix appendix, as well as the club‐shaped organs located directly above the female flowers. Volatile analysis of various regions of the appendix and the club‐shaped organs led to the identification of 163 compounds emitted by the appendix top, 124 by the appendix bottom and 105 by the club‐shaped organs. The dominant compounds in all investigated tissues were monoterpenes and sesquiterpenes that were accompanied by numerous aliphatic, aromatic, sulphur‐ and nitrogen‐containing compounds of other biosynthetic origins. Within the appendix, levels of one monoterpene, β‐citronellene, showed considerable variation; it constituted the major compound in the appendix top and gradually decreased in the lower regions, being undetectable in the base. The other prominent monoterpenes, α‐pinene, β‐pinene, limonene, α‐phellandrene and β‐phellandrene, showed no changes along the appendix. The club‐shaped organs located at the base of the floral chamber also emitted volatiles, though of different composition: the monoterpenes α‐terpinolene and linalool constituted major amounts, instead of β‐pinene and β‐citronellene. These qualitative differences and the absence of methanethiol in the club‐shaped organs result in them having a pleasant flowery odour, in contrast to the foul‐smelling appendix. The quantitative spatial variation of β‐citronellene within the appendix and the existence of a second osmophore within the floral chamber, emitting a different scent, suggest that both phenomena might participate in creating an odour gradient for efficient pollinator attraction. Apart from β‐citronellene, nearly all major components of the appendix have already been identified as specific attractants to a broad range of insects that have been observed to be lured to the odour‐emitting inflorescence. Most likely, the club‐shaped organ odour serves to induce the insects attracted by the appendix to move towards the floral chamber. A comparison of the relative emission rates demonstrated that performance of the club‐shaped organs equals or even exceeds the appendix. In the club‐shaped organ tissues, multivesicular bodies, originating from lipid droplets, are the most notable organelles before and during odour production. They fuse with the plasma membrane, releasing their content to the exterior of the cell. The exit route for the volatiles is an extensive intercellular channel system that extends to the surface of the club‐shaped organs. Thus, chemical and ultrastructural analyses suggest, in contrast to previous studies, that the club‐shaped organs function as an osmophore rather than a food source for insects.
Primary Colonization of Volcanic Rocks by Plants in Arid Baja California, Mexico
Authors: Bashan Y. , Li C. Y. , Lebsky V. K. , Moreno M. , De‐Bashan L. E.
Published: July 2002

Abstract: In an arid region of Baja California Sur, Mexico, field observations, combined with chemical and physical analyses, mineral analysis and scanning electron microscopy of unweathered and weathered volcanic rocks, revealed the presence of rock‐colonizing plants (most are tree‐shaped cacti, possibly rock weathering), growing in volcanic rocks without benefit of soil. Many are at the seedling stage. At least four cactus species (Pachycereus pringlei [S. Wats] Britt. and Ross, Stenocereus thurberi [Engelm.] Buxb. subsp. thurberi, Mamillaria fraileana [Britt. and Rose] Boed., Opuntia cholla F. A. C. Weber), and one tree (wild fig, Ficus palmeri [S. Wats]) were capable of cracking, growing in and colonizing cliffs and rocks formed from ancient lava flows and, consequently, forming soil for succession by other plant species. This study shows that plant colonization of volcanic rocks may assist soil formation, which eventually leads to accumulation of soil, water and nutrients in a desert terrestrial ecosystem that otherwise lacks these essential plant‐growth variables.
Phylogenetic Relationships Among Olea Species, Based on Nucleotide Variation at a Non‐Coding Chloroplast DNA Region
Authors: Baldoni L. , Guerrero C. , Sossey‐Aloui K. , Abbott A. G. , Angiolillo A. , Lumaret R.
Published: July 2002

Abstract: The purpose of this study was to assess nucleotide variation at a non‐coding chloroplast DNA region in Olea species, to evaluate their phylogenetic relationships within the Olea genus and, more particularly, to clarify the relationships between cultivated olive (O. europaea) and the other taxa of section Olea. The analysis was made on an intergenic region between the trnT(UGU) and trnL(UAA) 5′ exon, within a large single copy region of the chloroplast genome. Site‐specific primers were used to amplify the region by PCR. This sequence analysis was applied to the same array of Olea species as assayed by Lumaret et al. (2000[16]) using cpDNA RFLPs, thus making it possible to compare phylogenetic relationships analysed at two complementary levels of cpDNA variation. On the 666 bp aligned sequence, 8 different haplotypes were defined, with 9 single nucleotide mutations, a different length of a poly‐T region and an indel for O. paniculata. Haplotypes were shared by the species pairs O. europaea‐O.laperrinei, O. maroccana‐O. cerasiformis, O. capensis‐O. lancea and O. africana‐O.indica. Phylogenetic analyses of these data distinguished four groups: the species Olea capensis and O. lancea, which both belong to subgenus Ligustroides, the Olea forms from southeast Africa, those from Asia and the taxa of northwest Africa and the Mediterranean Basin, which include olive crop. The results are consistent with those previously found using cpDNA RFLPs, with some minor differences observed within each group. They constitute further evidence to clarify the phylogeny of Olea.
Electron impact ionization of water molecule
Authors: Champion C. , Hanssen J. , Hervieux P. A.
Published: July 2002

In the present paper, differential and total cross sections are calculated for the interaction of electrons with a water molecule. The calculations are performed in the distorted wave Born approximation framework where the incident and scattered (fast) electrons are described by a plane wave function, whereas the ejected (slow) electron is described by a distorted wave function. From the fivefold differential cross sections, triply and singly differential cross sections have been calculated by successive integrations. In these conditions, very good agreement is found with available experimental measurements essentially limited to triply and singly ionization cross sections. Finally, a comparison of our results with a large set of experimental data of total ionization cross sections exhibits very good agreement.
Synthesis of bulk In2O3–Sc2O3 and their transparent conducting oxide films
Authors: Qadri Syed B. , Kim Heungsoo
Published: July 2002

Bulk In2O3–Sc2O3 alloys were synthesized in a cubic phase (space group Ia3) with Sc2O3 content varying between 0 and 30 wt %. The lattice parameters of these alloys showed a linear dependence on the composition. Films were deposited on glass substrates at a temperature of 250 °C in an oxygen pressure of 10 mTorr using a pulsed laser deposition technique. Films with Sc2O3 composition varying between 0 and 10 weight percent show resistivities varying between 1.85×10−3 and 2.18×10−1 Ω cm, while their optical transparencies were more than 80% for wavelengths between 400 and 900 nm.
Electronic and rotational energy transfer in F(2P1/2)+H2 collisions at ultracold temperatures
Authors: Krems Roman , Dalgarno Alexander
Published: July 2002

The dynamics of F(2P1/2)+H2 scattering at ultracold temperatures is studied. It is shown that both the rotational and vibrational excitation of H2 molecules decrease substantially the efficiency of spin–orbit relaxation in F+H2 collisions. It is observed that the near-resonant electronic transition leading to rotational excitation of H2(j=0) is of the same magnitude at high energies as the off-resonant transition in which the rotational angular momentum of H2 is preserved but becomes dominant in ultracold collisions. The zero temperature rate constant for spin-orbit relaxation of F is computed and suggestions are made as to the chemical reactivity of F(2P1/2) atoms at ultracold temperatures. It is found that rotational relaxation of excited H2 molecules is significantly enhanced by electronic transitions in F atoms and the electronic relaxation in F(2P1/2)+H2(j>0) collisions is suppressed by rotational relaxation of H2.
New developments in the polarizable continuum model for quantum mechanical and classical calculations on molecules in solution
Authors: Cossi Maurizio , Scalmani Giovanni , Rega Nadia , Barone Vincenzo
Published: July 2002

The polarizable continuum model (PCM), used for the calculation of molecular energies, structures, and properties in liquid solution has been deeply revised, in order to extend its range of applications and to improve its accuracy. The main changes effect the definition of solute cavities, of solvation charges and of the PCM operator added to the molecular Hamiltonian, as well as the calculation of energy gradients, to be used in geometry optimizations. The procedure can be equally applied to quantum mechanical and to classical calculations; as shown also with a number of numerical tests, this PCM formulation is very efficient and reliable. It can also be applied to very large solutes, since all the bottlenecks have been eliminated to obtain a procedure whose time and memory requirements scale linearly with solute size. The present procedure can be used to compute solvent effects at a number of different levels of theory on almost all the chemical systems which can be studied in vacuo.
Formation and stabilization of nanosize grains in ferromagnetic thin films by dispersed C60
Authors: Zheng Lingyi A. , Barrera Enrique V. , Shull Robert D.
Published: July 2002

Thermal stability and formation of the nanostructured metal–C60 films have been studied. Comparative grain growth kinetic studies at 450 °C between Co–C60 and Co films show higher thermal stability and significantly slower grain growth in the Co–C60 thin film than in the Co film. Atomic force microscope observation shows that the surface of the Co film is coarsened by severe grain growth and formation of surface thermal grooves after annealing at 450 °C while the surface of the Co–C60 film remains smooth due to high thermal stability and slow grain growth in the film. A self-assembly grain growth mechanism is proposed to explain the formation of the uniform columnar nanosize grain structures in these ferromagnetic metal–C60 thin films. Estimated grain sizes based on this mechanism agree with the experimental measurement and give a relationship between the grain size and the C60 concentration in these films. These results indicate that C60 has a dual function of forming and stabilizing the nanosize grains in the metal–C60 films.
Surface anchoring on layers of grafted liquid-crystalline chain molecules: A computer simulation
Authors: Lange Harald , Schmid Friederike
Published: July 2002

By Monte Carlo simulations of a soft ellipsoid model for liquid crystals, we study whether a layer of grafted liquid-crystalline chain molecules can induce tilt in a nematic fluid. The chains are fairly short (four monomers) and made of the same particles as the solvent. They are attached to a substrate which favors parallel (planar) alignment. At low grafting densities, the substrate dominates and we observe planar alignment. On increasing the grafting density, we find a first order transition from planar to tilted alignment. Beyond the transition, the tilt angle with respect to the surface normal decreases continuously. The range of accessible anchoring angles is quite large.
Miscible displacements in capillary tubes: Influence of Korteweg stresses and divergence effects
Authors: Chen Ching-Yao , Meiburg Eckart
Published: July 2002

The question is addressed as to whether Korteweg stresses and/or divergence effects can potentially account for discrepancies observed between conventional Stokes flow simulations (Chen and Meiburg) and experiments (Petitjeans and Maxworthy) for miscible flows in capillary tubes. An estimate of the vorticity and stream function fields induced by the Korteweg stresses is presented, which shows these stresses to result in the formation of a vortex ring structure near the tip of the concentration front. Through this mechanism the propagation velocity of the concentration front is reduced, in agreement with the experimental observations. Divergence effects, on the other hand, are seen to be very small, and they have a negligible influence on the tip velocity. As a result, we can conclude that they are not responsible for the discrepancies between experiments and conventional Stokes simulations.
One-dimensional unsteady fluid motion between two infinite walls
Authors: Lemdiasov R. A. , Tenishev V. M. , Fedoseyev A. I.
Published: July 2002

We considered an incompressible fluid motion driven by space-dependent body force. For a one-dimensional case, the problem was solved analytically, with the arbitrary choice of body force coordinate dependence. It was shown that unsteady fluid flow can be represented as a series of separate modes, each with its own characteristic response time.
Emission spectrometry diagnostic of sputtered titanium in magnetron amplified discharges
Authors: Nouvellon C. , Konstantinidis S. , Dauchot J. P. , Wautelet M. , Jouan P. Y. , Ricard A. , Hecq M.
Published: July 2002

The plasma of a dc discharge amplified by a rf coil is studied by emission spectroscopy. The effects of the induction coil are studied for titanium sputtered in an argon gas. The pressure range is 5–40 mTorr with 100 to 1000 W dc applied at the cathode and 0 to 500 W in the rf coil. The titanium emission line intensities are reported versus rf power. At high rf power and high pressure, titanium emission saturates while there is a linear increase with rf power for titanium ions emission. These results suggest a two-step mechanism for the production of excited titanium ions. With such a mechanism, titanium neutral is mainly lost by ion production (the diffusion loss is lower) and titanium ion is mainly lost by diffusion (loss by second ionization of Ti+ is weak). The Ti/Ar emission line ratio, representing the titanium density, decreases when a rf power is applied to the coil as a result of an efficient titanium ionization reaction by electrons.
Time and length scales of polymer melts studied by coarse-grained molecular dynamics simulations
Authors: Padding J. T. , Briels W. J.
Published: July 2002

We present coarse-grained molecular dynamics simulations of linear polyethylene (PE) melts, ranging in chain length from C80 to C1000. The employed effective potentials, frictions, and random forces are all derived from detailed molecular dynamics simulations, leaving no adjustable parameters. Uncrossability constraints are introduced in the coarse-grained model to prevent unphysical bond crossings. The dynamic and zero-shear rate rheological properties are investigated and compared with experiment and other simulation work. In the analysis of the internal relaxations we identify a new length scale, called the slowing down length Ns, which is smaller than the entanglement length Ne. The effective segmental friction rapidly increases around Ns leading, at constant density, to a transition in the scaling of the diffusion coefficient from D∼N−1 to D∼N−2, a transition in the scaling of the viscosity from η∼N to η∼N1.8, and conspicuous nonexponential relaxation behavior. These effects are attributed to strong local kinetic constraints caused by both chain stiffness and interchain interactions. The onset of nonlocal (entanglement) effects occurs at a chain length of C120. Full entanglement effects are observed only above C400, where the shear relaxation modulus displays a plateau and the single chain coherent dynamic structure factor agrees with the reptation model. In this region the viscosity scales as η∼N3.6, the tube diameter is d≈5.4 nm, the entanglement molecular weight is Me≈1700 g/mol, and the plateau modulus is GN0≈2.4 MPa, all in good agreement with experimental data.
RF voltage modulations and the coupled bunch instabilities
Authors: Wang M. H. , Lee S. Y.
Published: July 2002

The effects of rf cavity voltage modulation on longitudinal beam dynamics were studied experimentally at Taiwan Light Source by using a streak camera system that measured the attractor amplitude of the beam bunch. Theoretical description of rf voltage modulation that includes the effect of nonzero synchronous phase has been developed. The characteristics of the quadrupole parametric resonance in the single bunch and multibunch modes were studied and compared with theory. The formation of beamlets in the bucket helps to damp the coherent coupled bunch oscillation driven by parasitic modes of the rf cavity. This beam manipulation technique can be employed to alleviate stability problems associated with high brightness electron storage rings.