bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of GH replacement therapy in adults on serum levels of leptin and ghrelin: the role of lipolysis
Authors: Vestergaard E T , Hansen T K , Nielsen S , Moller N , Christiansen J S , Jorgensen J O L
Published: September 2005

Objective: The regulation and function of systemic ghrelin levels appear to be associated with food intake and energy balance rather than GH. Since GH, in turn, acutely induces lipolysis and insulin resistance in skeletal muscle, we aimed to study the isolated and combined effects of GH, free fatty acids (FFAs) and insulin sensitivity on circulating ghrelin levels in human subjects.

Design: Seven GH-deficient patients (aged 37 ± 4 years (mean ± s.e.)) were studied on four occasions in a 2 × 2 factorial design with and without GH substitution and with and without administration of acipimox, which lowers FFA levels by inhibition of the hormone-sensitive lipase, in the basal state and during a hyperinsulinemic euglycemic clamp.

Results: Serum FFA levels decreased with acipimox administration irrespective of GH status. The GH-induced reduction in insulin sensitivity was countered by acipimox. Fasting ghrelin levels decreased insignificantly during GH administration alone, but were reduced by 33% during co-administration of GH and acipimox (Aci) (in ng/l): 860 ± 120 (−GH − Aci), 711 ± 130 (−GH + Aci), 806 ± 130 (+GH − Aci), 574 ± 129 (+GH + Aci), P < 0.01. The clamp was associated with a further, moderate lowering of ghrelin. GH and acipimox induced a reciprocal 25% increase in serum leptin levels (μg/l): 11.2 ± 4.4 (−GH − Aci), 11.7 ± 4.4 (−GH + Aci), 11.5 ± 4.4 (+GH − Aci), 13.9 ± 4.2 (+GH + Aci), P = 0.005.

Conclusion: Our data suggest that antilipolysis via suppression of the hormone-sensitive lipase in combination with GH administration is associated with significant and reciprocal changes in ghrelin and leptin.
Cell cycle-dependent localization and possible roles of the small GTPase Ran in mouse oocyte maturation, fertilization and early cleavage
Authors: Cao Yun-Kao , Zhong Zhi-Sheng , Chen Da-Yuan , Zhang Gui-Xue , Schatten Heide , Sun Qing-Yuan
Published: September 2005

The small GTPase Ran controls numerous cellular processes of the mitotic cell cycle. In this experiment, we investigated the localization and possible roles of Ran during mouse oocyte meiotic maturation, fertilization and early cleavage by using confocal laser scanning microscopy, antibody microinjection and microtubule disturbance. The results showed that Ran was localized mainly in the nucleus (except for the nucleolus) in the oocyte, zygote and early embryo. At pro-metaphase of meiosis I, Ran distributed throughout the cell, but predominantly concentrated around the condensed chromosomes. During the completion of meiosis I and meiosis II, it concentrated to the meiotic spindle microtubules except for the midbody region. After sperm penetration, Ran dispersed with the extrusion of the second polar body and gradually concentrated in the male and female pronuclei thereafter. Ran was also observed to exist diffusely in the cytoplasm in prophase; it concentrated at the mitotic spindle, and migrated to the nucleus during early cleavage. Ran’s concentration around the spindle disappeared when microtubule assembly was inhibited by colchicine, while it was concentrated around the chromosomes after microtubule stabilization with taxol treatment. Ran did not display any role in cytokinesis during division when pseudo-cleavage of germinal vesicle-intact oocytes was induced. Anti-Ran antibody microinjection decreased the germinal vesicle breakdown and the first polar body extrusion, and distorted spindle organization and chromosome alignment. Our results indicate that Ran has a cell cycle-dependent localization and may have regulatory roles in cell cycle progression and microtubule organization in mouse oocytes, fertilized eggs and early embryos.
Genomic imprinting and reproduction
Authors: Swales A K E , Spears N
Published: September 2005

Genomic imprinting is the parent-of-origin specific gene expression which is a vital mechanism through both development and adult life. One of the key elements of the imprinting mechanism is DNA methylation, controlled by DNA methyltransferase enzymes. Germ cells undergo reprogramming to ensure that sex-specific genomic imprinting is initiated, thus allowing normal embryo development to progress after fertilisation. In some cases, errors in genomic imprinting are embryo lethal while in others they lead to developmental disorders and disease. Recent studies have suggested a link between the use of assisted reproductive techniques and an increase in normally rare imprinting disorders. A greater understanding of the mechanisms of genomic imprinting and the factors that influence them are important in assessing the safety of these techniques.
Expression profile of protein kinase C isozymes in preimplantation mouse development
Authors: Dehghani Hesam , Hahnel Ann C
Published: September 2005

In the preimplantation mouse embryo, the protein kinase C (PKC) family has been implicated in regulation of egg activation, progression of meiotic and mitotic cell cycles, embryo compaction, and blastulation, but the involvement of the individual isozymes is largely unknown. Here, using semiquantitative immunocytochemistry and confocal microscopy we analyze the relative amount and subcellular distribution of ten isozymes of PKC (α, βI, βII, γ, δ, ε, η, 𝛉, ζ, ι/λ) and a PKC-anchoring protein, receptor for activated C-kinase 1 (RACK1). Our results show that all of these isoforms of PKC are present between the two-cell and blastocyst stages of mouse preimplantation development, and that each has a distinct, dynamic pattern and level of expression. The data suggest that different complements of the isozymes are involved in various steps of preimplantation development, and will serve as a framework for further functional studies of the individual isozymes. In particular, there was a transient increase in the nuclear concentration of several isozymes at the early four-cell stage, suggesting that some of the PKC isozymes might be involved in regulation of nuclear organization and function in the early mouse embryo.
Subcellular localization of protein kinase C δ and ε affects transcriptional and post-transcriptional processes in four-cell mouse embryos
Authors: Dehghani Hesam , Reith Cara , Hahnel Ann C
Published: September 2005

During mouse preimplantation development, two isozymes of protein kinase C (PKC), δ and ε, transiently localize to nuclei at the early four-cell stage. In order to study their functions at this stage, we altered the subcellular localization of these isozymes (ratio of nuclear to cytoplasmic concentrations) with peptides that specifically activate or inhibit translocation of each isozyme. The effects of altering nuclear concentration of each isozyme on transcription (5-bromouridine 5′-triphosphate (BrUTP) incorporation), amount and distribution of small nuclear ribonucleoproteins (snRNPs), nucleolar dynamics (immunocytochemistry for Smith antigen (Sm) protein) and the activity of embryonic alkaline phosphatase (EAP; histochemistry) were examined. We found that nuclear concentration of PKC ε correlated with total mRNA transcription. Higher nuclear concentrations of both PKC δ and ε decreased storage of snRNPs in Cajal bodies and decreased the number of nucleoli, but did not affect the nucleoplasmic concentration of snRNPs. Inhibiting translocation of PKC δ out of the nucleus at the early four-cell stage decreased cytoplasmic EAP activity, whereas inhibiting translocation of PKC ε increased EAP activity slightly. These results indicate that translocation of PKC δ and ε in and out of nuclei at the early four-cell stage in mice can affect transcription or message processing, and that sequestration of these PKC in nuclei can also affect the activity of a cytoplasmic protein (EAP).
Epidermal Growth Factor Is a Neuronal Differentiation Factor for Retinal Stem Cells In Vitro
Authors: Angénieux Brigitte , Schorderet Daniel F. , Arsenijevic Yvan
Published: September 2005

Stem cells are a tool for in vitro elucidation of the putative role of factors on cell fate. Herein we analyze the role of epidermal growth factor (EGF) on progeny derived from retinal stem cells (RSCs). We isolated cells from neuroretinas of neonate mice. All the proliferating cells harbored the radial glia marker RC2, expressed transcription factors usually found in radial glia (Mash1, Pax6), and met the criteria of stem cells: high capacity of expansion, maintenance of an undifferentiated state, and multipotency demonstrated by clonal analysis. We analyzed the differentiation 7 days after transfer of the cells in different culture media. In absence of serum, EGF led to the expression of the neuronal marker β-tubulin-III and acquisition of neuronal morphology in 15% of the cells. Analysis of cell proliferation by bromodeoxyuridine incorporation revealed that EGF mainly induced the formation of neurons without stimulating cell cycle progression. Moreover, a pulse of 2-hour EGF stimulation was sufficient to induce neuronal differentiation. Some neurons were committed to the retinal ganglion cell (RGC) phenotype, as revealed by the expression of retinal ganglion markers (Ath5, Brn3b, and melanopsin) and in a few cases to other retinal phenotypes (photoreceptors [PRs] and bipolar cells). We confirmed that the late RSCs were not restricted over time and that they conserved their multipotency by generating retinal phenotypes that usually appear at early (RGC) or late (PRs) developmental stages. Our results show that EGF is not only a factor controlling glial development, as previously shown, but also a potent differentiation factor for retinal neurons, at least in vitro.
Characterization of Mesenchymal Stem Cells Isolated from Mouse Fetal Bone Marrow
Authors: Wang Xiaoli , Hisha Hiroko , Taketani Shigeru , Adachi Yasushi , Li Qiang , Cui Wenhao , Cui Yunze , Wang Jianfeng , Song Changye , Mizokami Tomomi , Okazaki Satoshi , Li Qing , Fan Tianxue , Fan Hongxue , Lian Zhexiong , Gershwin M. Eric , Ikehara Susumu
Published: September 2005

Mesenchymal stem cells (MSCs) are defined as cells that can differentiate into multiple mesenchymal lineage cells. MSCs have some features (surface molecules and cytokine production, etc.) common to so-called traditional bone marrow (BM) stromal cells, which have the capacity to support hemopoiesis. In the present study, we isolated murine MSCs (mMSCs) from the fetal BM using an anti-PA6 monoclonal antibody (mAb) that is specific for bone marrow stromal cells. The mMSCs, called FMS/PA6-P cells, are adherent, fibroblastic, and extensively expanded and have the ability to differentiate not only into osteoblasts and adipocytes but also into vascular endothelial cells. The FMS/PA6-P cells produce a broad spectrum of cytokines and growth factors closely related to hemopoiesis and show good hemopoiesis-supporting capacity both in vivo and in vitro, suggesting that they are a component of the hemopoietic stem cell niche in vivo. Interestingly, although the FMS/PA6-P cells express a high level of the PA6 molecule, which is reactive with anti-PA6 mAb, they gradually lose their ability to express this molecule during the course of differentiation into osteoblasts and adipocytes, indicating that the PA6 molecule might serve as a novel marker of mMSCs.
Paint
Authors: Van De Mark Michael R. , Sandefur Kathryn D. , Durham Katherine A.
Published: September 2005

Paint has one of the most important roles in our economy. Its job is to protect homes, cars and infrastructure from all adversities and at the same time add appearance and aesthetics to the painted item. The main functions of a paint are to protect and beautify the substrate it is applied to. Paint is a liquid coating that is pigmented to produce an opaque solid film after application.

Paints have been used for about 30,000 years. Ancient paintings have been found on the walls of caves in France. These early coatings were decorative and were made from naturally occurring materials. Over the years different technologies have evolved to meet the challenges. Alkyds were an early improvement over oil type paints. Latex technology came out of WWII and the search for a rubber replacement. Today higher solids coatings and solvent free paints are coming out of the environmental movement.

This article discusses the different types of paints commonly used in architectural applications, which include house and trade sales paints. Coatings commonly encountered in architectural applications include primers, stains, varnishes, sealers, interior and exterior house paints. Today these coatings may be obtained in a variety of types including oil‐based, latex, urethane, and others. The choice of color is almost endless in most interior and exterior house paints thanks to the industries ability to tint and the advent of the color computer (spectrophotometer). The choice of pigment, resin, extender, solvents, and additives type, as well as the amount, all play an important role in the performance of a paint. The manufacturing of the paint requires the quantitative addition and mixing of components in the correct order to produce a consistent paint. The paint manufacturer must meet, through rigorous testing, the needs of the specific application. The coating, however, is only as good as the surface preparation. The end user must use the paint in accordance with the manufacturer’s guidelines or the paint may fail.

Paints have been a bargain over the years. The price of a gallon of paint has remained low even though the price of other goods has increased. The application of technology and economy of scale has allowed this savings over the years. Early latex paints were not good performers, today they out perform most oil‐based products. As technology continues to evolve, it will improve coatings even further.
Nanotechnology
Authors: Milev Adriyan S. , Kannangara G. S. Kamali , Wilson Michael A.
Published: September 2005

Along with genetic engineering, nanotechnology appears to be the other big growth area of this century. Nanotechnology means building useful things at the 10−9m level. Nanotechnology is not synonymous with chemistry, since it is more specific and concerned with observing atoms and molecules and manipulating them through visual observation at the nanoscale level. However, it may eventually encompass all of chemistry and a large part of physics and molecular biology. Feynman’s and Drexler’s definitions now define the field of molecular nanotechnology, which is sometimes also called molecular manufacturing. The latter is a poor description, since it is synonymous with synthetic chemistry. Other terms, such as molecular engineering, have also been used, but these terms have also broadened to include manipulating larger than atomic entities and the ability to design and manufacture materials and devices that are tens or hundreds of atoms across. Once material sizes are reduced below 100 nm, they begin demonstrating an array of unique properties based on quantum mechanical effects, rather than the familiar Newtonian mechanics that operate in the macroscopic scale. There are two fundamental strategies used to produce very small machines or devices. The “top‐down” approach takes a chunk of material and by physical methods carves out the desired nanostructure. The “bottom‐up” approach is the most promising since increasingly complex structures are intentionally assembled from nanoscale components to build larger scale devices. This article provides a short overview of current nanotechnology with special emphasis on fullerene and carbon nanotube properties and applications that have been pursued during the past decade. Development in covalent and non covalent fullerene and carbon nanotube functionalization led to the preparation of new supramolecular architectures such as electron acceptors for photo induced energy transfer. These molecular structures feature marked properties as a consequence of the existence of the fullerene or carbon nanotube components. A review of efficient ways on the organic functionalization of fullerenes and carbon nanotubes is also provided. Langmuir‐Blodgett and self assembly are two commonly used techniques for organizing functionalized fullerenes and nanotubes in highly ordred thin films. Characterization techniques for these films are briefly presented.
Paint and Finish Removers
Authors: White David L. , Bardole Jay A.
Published: September 2005

Finish removers play an important role in the recycling of durable goods. Finishes are removed from antiques in the process of restoration. Original equipment manufacturers remove coatings from rejected parts. Lead‐based paints are removed for the safety of those living in lead exposure environments. Finishes are removed from woods, metals, and plastics. No single type of remover can be effective in all of the 107 different applications in which removers are used. Finish removers include a major active component. The formulator can also choose from cosolvents, diluents, evaporation retardants, emulsifiers, activators, thickeners, and corrosion inhibitors to make the remover best suited for any application. Considerations important when selecting a finish remover include how well it works, how quickly it works, and the cost per amount of work done. It is also important to consider the safety of the person using the remover and the impact the finish removal process will have on the environment. Manufacturing is best done in closed kettles for the protection of the worker and the environment.
Perfumes
Authors: Schreiber William L.
Published: September 2005

This article surveys the essential aspects of perfume creation and the fragrance industry, providing brief notes on the history of fragrance use and a list of odor descriptors. It discusses the creation of and illustrates with examples both fine and functional fragrances, summarizing in particular the performance requirements of the latter group in a number of applications. It describes different perfume ingredients, natural as well as synthetic, and offers information about their origin, fragrance characteristics, and uses. In addition, it examines the chemical structures and odors of some typical aroma chemicals by functional groups.The article also covers such topics on fragrance research as the analysis of natural products, synthesis of aroma chemicals, structure–odor considerations, process research and development, and psychological effects of fragrance. Finally, it reviews the manufacture and quality control of perfumes and ingredients, and supplies an overview of the economic, safety, environmental, and regulatory aspects of the industry.
Pesticides
Authors: Leng Marguerite L. ,   Updated by Staff
Published: September 2005

A pesticide is any substance or mixture of substances used to control living organisms that cause damage or economic loss, or transmit or produce disease, including such animals as insects or mice, unwanted plants, microorganisms such as those causing plant diseases, or viruses. Early pesticides were simple, often toxic inorganic compounds having a broad spectrum of activity, and often applied indiscriminately at high rates. Newer crop protection agents are generally complex organic chemicals, which may bind to a specific enzyme receptor. Some commercial pesticides are biological agents.

Pesticide use in the United States include herbicides (the largest sector), insecticides, fungicides, and others, including household disinfectants, repellents, rodenticides, etc. All pesticides produced and used in the United States must be reviewed and registered by the U.S. EPA. Extensive studies on chemistry, residues in treated food commodities, environmental fate, and toxicity to laboratory animals and wildlife, to demonstrate that proposed uses do not cause undue harm to humans or the environment, are required. The use of genetically modified microorganisms as pesticides and their impact is discussed. Problems for the agrochemical industry and for government regulators include the lack of harmonization of study requirements in developed countries, and public perception that pesticides are not adequately tested and are inherently harmful.
Potassium
Authors: Chiu Kuen‐Wai ,   Updated by Staff
Published: September 2005

Potassium, the third element in the alkali metal series, is manufactured by a reduction process using sodium and potassium chloride, operated at high temperature. Sodium chloride is the by‐product.

Potassium is itself a powerful reducing agent and can serve as an electron source for many chemical reactions. It forms liquid–metal alloys with other alkali metals. The potassium–sodium liquid alloys are ideal for use as heat‐transfer, electrical contact, and hydraulic fluids.

Commercially important potassium derivatives prepared from potassium metal include potassium–sodium alloys, alkoxides, amides, hydride, graphite, and superoxide. Most are utilized as reducing agents. A potassium–sodium dispersion provides higher reaction surface and allows reduction at lower temperatures than the individual metals. Potassium alkoxides are strong, nonnucleophilic bases that have good solubilities, selectivities, and stabilities, and are ideal for deprotonation reactions. Potassium graphite, an intercalation compound, can serve as a solid reducing agent. Potassium superoxide, a radical anion, is a strong oxidizing agent, generating oxygen in contact with moisture and carbon dioxide.
Cover Picture: Direct Correlation of Organic Semiconductor Film Structure to Field‐Effect Mobility (Adv. Mater. 19/2005)
Authors: DeLongchamp D. M. , Sambasivan S. , Fischer D. A. , Lin E. K. , Chang P. , Murphy A. R. , Fréchet J. M. J. , Subramanian V.
Published: September 2005

The use of near‐edge X‐ray absorption fine structure (NEXAFS) spectroscopy as a non‐destructive technique to quantify the simultaneous chemical conversion, molecular ordering, and defect formation of soluble oligothiophene precursor films intended for application in organic field‐effect transistors is demonstrated on p. 2340 by DeLongchamp and co‐workers. Illustrated from left to right, with increasing temperature: a) as‐cast, the molecules are weakly oriented; b) at the conversion onset, they become isotropic; c) after full conversion, they are strongly oriented and exhibit maximum field‐effect mobility; and d) overheating reduces film coverage and decreases their orientation, thus lowering their performance.
Myocardial injury or infarction associated with fat embolism in sickle cell disease: A report of three cases with survival
Authors: Dang Nghia C. , Johnson Cage , Eslami‐Farsani Mahmoud , Haywood L. Julian
Published: September 2005

Fat embolism represents a dread complication of sickle cell hemoglobinopathies. We present the details of three cases that, in addition to an acute chest syndrome, had serological and clinical parameters consistent with myocardial damage. A favorable outcome was obtained with judicious use of blood transfusion. Am. J. Hematol. 80:133–136, 2005. © 2005 Wiley‐Liss, Inc.
Myelofibrosis‐associated massive splenomegaly: A cause of increased intra‐abdominal pressure, pulmonary hypertension, and positional dyspnea
Authors: Ziakas Panayiotis D. , Voulgarelis Michael , Felekouras Evagelos , Anagnostou Dimitra , Tzelepis George E.
Published: September 2005

We describe a patient with myelofibrosis, giant splenomegaly, and pulmonary hypertension related to increased intra‐abdominal pressure. Focusing on alterations in hemodynamic studies, we conclude that in patients with myelofibrosis, dyspnea, and hypoxemia, the measurement of intra‐abdominal pressure should be included in the initial evaluation. It is an inexpensive, non‐invasive diagnostic tool that can provide crucial information about the cause of dyspnea and disclose the pathogenetic link between massive splenomegaly and pulmonary compromise in myelofibrosis. Am. J. Hematol. 80:128–132, 2005. © 2005 Wiley‐Liss, Inc.
Pulmonary complications following hematopoietic stem cell transplantation: Diagnostic approaches
Authors: Sirithanakul Kasem , Salloum Anan , Klein Jared L. , Soubani Ayman O.
Published: September 2005

Pulmonary complications are a significant cause of morbidity and mortality in hematopoietic stem cell transplant recipients. Pulmonary infiltrates in such patients pose a major challenge for clinicians because of the wide differential diagnosis of infectious and noninfectious conditions. It is rare for the diagnosis to be made by chest radiograph, and commonly these patients will need further invasive and noninvasive studies to confirm the etiology of the pulmonary infiltrates. This review describes the role of the different diagnostic tools available to reach a diagnosis in a timely manner in this patient population. Am. J. Hematol. 80:137–146, 2005. © 2005 Wiley‐Liss, Inc.
Three novel polymorphisms in the β globin gene
Authors: Nadkarni A. , Sakaguchi T. , Gorakshakar A. , Phanasgaonkar S. , Colah R. , Mohanty D. , Kiyama R.
Published: September 2005

We report on three novel polymorphisms in and around the β globin gene. Two of them are intronic (IVS2) polymorphisms (IVS 2 nt 200–203 (−CTTT) and IVS2 82–83 (−AG)). The third is a novel G→C substitution at nt +1707 related to the β globin cap site. This +1707 G→C polymorphism was detected in 23.5% of chromosomes among 140 samples from India. It seems to be a novel but common polymorphism among Indians. There was no linkage between these novel polymorphisms and any β thalassemia mutation. Am. J. Hematol. 80:161–163, 2005. © 2005 Wiley‐Liss, Inc.
Childhood and adult ALL: Differences in epigenetic lesions associated with cell cycle genes
Authors: Gutiérrez Marina I. , Siraj Abdul K. , Ibrahim Muna M. , Hussain Azhar , Bhatia Kishor
Published: September 2005

The impact of silencing tumor suppressor genes involved in cell proliferation in adult and pediatric ALL is still unknown. We analyzed methylation of the master regulators (p73, p53, Rb), CDKIs (p27, p57), and the INK4 locus (p15) in childhood ALLs and describe a relatively low frequency. Comparisons with adult ALL showed that p57 clearly differed in children (7% methylation) and adults (50% methylation). While >20% of adult ALL Ph1 chromosome‐negative undergo methylation of p73, p57, and p15, only 3% of childhood ALL carried such anomalies, which is very significant when a higher fraction of pediatric patients has non‐Ph1 ALL than do the adult patients. We have studied a large p57 CpG island and expression by real‐time RT‐PCR. We observed that 53% of childhood leukemias lacked p57 transcripts, and the overall level was 8‐fold lower than in normal lymphocytes (P < 0.0001). However, no correlation with methylation was found. Thus, loss of p57 expression in the absence of methylation may be frequent in childhood ALL, suggesting that methylation is not the sole mechanism of p57 downregulation. Methylation differences in ALL may be age‐related or, alternatively, reflect different pathogenesis. Am. J. Hematol. 80:158–160, 2005. © 2005 Wiley‐Liss, Inc.
Long‐term persistence of host cells detected by X‐chromosome gene‐based assay in patients undergoing gender‐mismatched hematopoietic stem cell transplantation
Authors: Karasawa Masamitsu , Yamane Arito , Mitsui Takeki , Irisawa Hiroyuki , Sakura Tohru , Matsushima Takafumi , Tsukamoto Norifumi , Nojima Yoshihisa , Miyawaki Shuichi
Published: September 2005

Using our recently developed human androgen receptor (HUMARA) gene‐based chimerism assay, long‐term chimerism was investigated in female patients who underwent hematopoietic stem cell transplantation (HCT) with cells from male donors. After restriction digestion of samples, we detected a small number of female‐derived cells within a large population of male‐derived cells, with a sensitivity from 0.1% to 0.05%. Chimerism was examined in four patients with myeloid malignancies: two patients with acute myeloid leukemia (AML) from myelodysplastic syndrome (MDS), and one patient each with AML M3 and AML M4. All patients underwent myeloablative conditioning regimens and exhibited good clinical results during a median follow‐up period of 6.6 years (range, 3.4–7.5 years). Female‐derived cells were detected throughout the entire follow‐up period in all bone marrow samples, but they became undetectable in the peripheral blood samples of 3 patients. Moreover, the HUMARA band pattern suggests that these residual host cells were normal cells. This study confirms the usefulness of the HUMARA gene‐based assay, which showed that patients undergoing HCT frequently show mixed chimerism (MC) for a long period, especially in bone marrow, although the possibility of contamination by host stromal cells cannot be excluded. Am. J. Hematol. 80:101–105, 2005. © 2005 Wiley‐Liss, Inc.
Confirmation of the association between a polymorphism in the promoter region of the prodynorphin gene and cocaine dependence
Authors: Dahl John P. , Weller Andrew E. , Kampman Kyle M. , Oslin David W. , Lohoff Falk W. , Ferraro Thomas N. , O'Brien Charles P. , Berrettini Wade H.
Published: September 2005

The endogenous opioid system has been shown to have a role in the biological processes involved in addiction to numerous drugs of abuse including cocaine. It has recently been reported that the variable nucleotide tandem repeat (VNTR) polymorphism in the 5′ promoter region of the prodynorphin gene, which encodes the precursor for three endogenous opioid peptides, is associated with the cocaine dependent phenotype. In order to confirm this finding, we genotyped the prodynorphin promoter polymorphism in cocaine dependent (n = 167) and control (n = 88) individuals of African descent. The results from this experiment indicate a statistically significant (χ2 = 5.64, OR = 1.59, P = 0.018) association between the prodynorphin promoter VNTR polymorphism and the cocaine dependent phenotype. In contrast to previous work showing increased risk conferred by one or two copies of the prodynorphin VNTR, the genotyping results from this study indicate that persons with three or four copies of this polymorphism are more likely to become cocaine dependent. This disparity suggests that the prodynorphin promoter VNTR may not be the functional polymorphism associating with the cocaine dependent phenotype. It is possible that different alleles of the prodynorphin promoter VNTR in the independent populations used for this and the previous study may be in linkage disequilibrium with a yet to be identified functional polymorphism in this gene. © 2005 Wiley‐Liss, Inc.
Abnormal elevation ofFMR1mRNA is associated with psychological symptoms in individuals with the fragile X premutation
Authors: Hessl David , Tassone Flora , Loesch Danuta Z. , Berry‐Kravis Elizabeth , Leehey Maureen A. , Gane Louise W. , Barbato Ingrid , Rice Cathlin , Gould Emma , Hall Deborah A. , Grigsby James , Wegelin Jacob A. , Harris Susan , Lewin Foster , Weinberg Dahlia , Hagerman Paul J. , Hagerman Randi J.
Published: September 2005

Until recently, individuals with premutation alleles (55–200 CGG repeats) of the fragile X mental retardation 1 (FMR1) gene were believed to be psychologically unaffected. However, the recent documentation of abnormal elevation ofFMR1mRNA, discovery of fragile X‐associated tremor/ataxia syndrome (FXTAS), and reports of psychiatric disorders in children and adults with the premutation have suggested a pathogenic gene–brain–behavior mechanism. In a large collaborative study, 68 men and 144 women with theFMR1premutation completed a psychological symptoms checklist andFMR1genetic testing, including determination of CGG repeat size, percentage ofFMR1protein (FMRP)‐positive lymphocytes, andFMR1mRNA levels. Relative to published norms, men and women with FXTAS symptoms reported higher levels of several types of psychological symptoms. In addition, men and women with the premutation and no overt evidence of FXTAS reported higher levels of obsessive‐compulsive symptoms. ElevatedFMR1mRNA, but not CGG repeat size or reduced FMRP (as measured by immunocytochemistry), was significantly associated with increased psychological symptoms, predominantly obsessive‐compulsive symptoms and psychoticism, in premutation men with and without FXTAS symptoms. There was no relationship between CGG repeat size,FMR1mRNA or FMRP and psychological symptoms in premutation women unless the sample was restricted to those with skewed X‐activation ratio toward >50% active premutation alleles. The results of this study support the hypothesis thatFMR1function is associated with psychological difficulties in individuals with the premutation, and provide evidence concordant with an RNA toxic gain‐of‐function model in a neuropsychiatric phenotype. © 2005 Wiley‐Liss, Inc.
A regular, hydrophobically modified polyampholyte as novel pour point depressant
Authors: Kudaibergenov Sarkyt E. , Didukh Alexander G. , Ibraeva Zhanar E. , Bimendina Larisa A. , Rullens Francois , Devillers Michel , Laschewsky André
Published: September 2005

A new regular polyampholyte, namely poly(N,N‐diallyl‐N‐octadecylamine‐alt‐(maleic acid)), was studied as an additive to crude oil. The amphiphilic polyampholyte proved to be an efficient pour point depressant, to inhibit the deposition of wax, and to improve the viscosity of waxy crude oil from the Akshabulak oilfield (Western Kazakhstan). On optimizing the concentration of the polymer, both the kinematical viscosity and the pour point of waxy crude oils were found to be strongly decreased. The morphology of the paraffin aggregates formed was compared before and after heat treatment of the waxy crude oils, in the presence and the absence of the polymer. The rheological characteristics of the waxy crude oil were markedly improved, in particular, by decreasing the plastic viscosity and the yield stress values upon addition the polymer. The inhibition of wax deposits in the presence of the amphiphilic polyampholyte was interpreted in terms of its interference with the wax crystallization process because of the formation of inverse micellar structures. Although the interaction of the cationic and the anionic groups on the polymer backbone stabilizes the smaller size of the aggregates, the hydrophobic side chains of the polymer provide nucleation sites and cocrystallize with the paraffins, thus modifying the paraffin crystal structure. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2101–2108, 2005
Effect of single yarn twist and ply to single yarn twist ratio on strength and elongation of ply yarns
Authors: Palaniswamy N. K. , Mohamed A. Peer
Published: September 2005

The amount of ply twist required to bring the surface fibers of the strand parallel to ply yarn axis is half the single yarn twist and, is experimentally verified by viewing the multifilament yarns longitudinally under Scanning Electron Microscope. The effect of single yarn twist and ply to single yarn twist ratio on strength and elongation of two‐ply cotton yarn have been studied. As the single yarn twist increases the tensile strength of the ply yarns with different levels of ply to single yarn twist ratio increases and at 130–140% of normal single yarn twist level, the ply yarns attain almost the same strength. Rate of improvement in tensile strength of cotton two‐ply yarn with respect to single yarn twist is more than that with respect to ply twist. The effect of ply to single yarn and cable to ply yarn twist ratio on strength and elongation of ply and cable multifilament yarns have been studied. Tensile strength of ply and cable multifilament yarns do not vary with the change in ratio of ply to single yarn twist and cable to ply twist respectively, particularly when the resultant yarn is finer. The cosine of average filament inclination to the ply yarn axis and that to the cable yarn axis do not vary much with different levels of ply to single yarn twist ratio and cable to ply yarn twist ratio respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2245–2252, 2005
Filled temperature‐sensitive poly(vinyl methyl ether) hydrogels
Authors: Theiss Daniel , Schmidt Thomas , Dorschner Helmut , Reichelt Rudolf , Arndt Karl‐Friedrich
Published: September 2005

Temperature‐sensitive hydrogels based on poly(vinyl methyl ether) (PVME) with ferroelectric or ferromagnetic properties were synthesized by high‐energy irradiation. Barium titanate and poly(vinylidene fluoride) (PVDF) were used as ferroelectric filler and Ni as ferromagnetic filler. The filled PVME hydrogels were synthesized by electron beam or γ‐ray irradiation (of a suspension with 5–50 wt % of filler (with respect to polymer mass) in a 20 wt % aqueous PVME solution). Filling of the gel reduces the absolute swelling degree at low temperatures, but do not influence the phase‐transition temperature of the gel. The particle distribution of the fillers inside the gel was visualized by field emission scanning electron microscopy. The fillers were incorporated in the PVME network and fixed because of their size (inorganic particles), as well as by chemical bonds (PVDF). The ferroelectric or ferromagnetic properties of the filled gels were proved. Measurements in a corresponding alternating field provide the hysteresis loop, for both the ferromagnetic and ferroelectric gel. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2253–2265, 2005
Polystyrene nanocomposite materials: Preparation, morphology, and mechanical, electrical, and thermal properties
Authors: Ma Chen‐Chi M. , Chen Yi‐Jie , Kuan Hsu‐Chiang
Published: September 2005

In this study, we prepared polystyrene (PS) resin nanocomposites with antistatic properties by melt‐blending PS with nanoscale zinc oxide (ZnO). The effects of nanoscale ZnO on the electrical and physical characteristics of the PS nanocomposites were investigated. Two kinds of nanoscale powders, spherical zinc oxide (s‐ZnO) and zinc oxide whisker (w‐ZnO), were selected. The coupling agents vinyltriethoxysilane (VTES) and phenyltriethoxysilane (PTES) were used to improve the compatibility between the nanopowders and PS resin. The addition of s‐ZnO and w‐ZnO improved the antistatic characteristics of the materials. The surface resistivities of the s‐ZnO and w‐ZnO nanocomposites were significantly reduced by modification with VTES and PTES. The addition of ZnO nanopowder increased the flexural modulus and reduced the flexural strength. The silane coupling agents improved the flexural properties of the nanocomposites. The glass‐transition temperatures and thermal degradation temperatures of the ZnO/PS nanocomposites increased with ZnO content. Treatment with silane increased the glass‐transition temperatures and thermal degradation temperatures of the composites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2266–2273, 2005
Preparation and characterization of UV‐curable MPS‐modified silica nanocomposite coats
Authors: Li Fusheng , Zhou Shuxue , Wu Limin
Published: September 2005

A series of UV‐curable nanocomposites were prepared with 3‐(trimethoxysilyl) propyl methacrylate (MPS) modified nanosilica under the initiation of 2,2‐dimethoxy‐1,2‐diphenylethan‐1‐one. It was found that MPS‐modified nanosilica together with free MPS could form transparent nanocomposite coats. As the particle size of nanosilica increased, the photopolymerization rate, final double bond conversion, and tack‐free time of nanocomposites increased while the surface roughness, glass‐transition temperature, and UV absorbance of nanocomposites decreased. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2274–2281, 2005
Preparation of sulfur‐modified powdered polychloroprene rubber by inverse coagulation
Authors: Zhang Anqiang , Wang Lianshi , Lin Yaling
Published: September 2005

Sulfur‐modified powdered polychloroprene rubber (PCR‐121) was prepared by inverse coagulation. A new coating agent (SN) was developed that could generate in situ the coating layer by inverse coagulation. The results show that this is a low‐cost, stable technology for the production of powdered rubber with a very low coating agent content. A powdering model based on the liquid–liquid stirring theory of noncoalescing, liquid–liquid dispersion was proven with uniform design testing. According to this model, the mass fraction of medium‐scale particles (1–3 mm) was only related to the agitation speed in the experimental range. Scanning electron microscopy (SEM) analysis showed that the PCR‐121 particles were single continuous particles coagulated from single chloroprene rubber latex drops. Energy spectrum analysis showed that a layer with higher Ca content was coated at the surface of PCR‐121 particles, which made PCR‐121 a free‐flowing powdered rubber. The results show that the variation of Mooney viscosity (ML1+4 100°C) from 30 to 130 had no obvious effect on the mechanical properties of PCR‐121. Compared with bale CR121, PCR‐121 had better mechanical properties. SEM analysis and energy spectrum analysis on the tensile fracture surfaces showed that the dispersion of compounding agents in PCR‐121 was better than that in bale CR121, which resulted in better mechanical properties in PCR‐121. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2109–2115, 2005
Methoxy poly(ethylene glycol)‐b‐poly(L‐lactic acid) copolymer nanoparticles as delivery vehicles for paclitaxel
Authors: Deng Liandong , Li Aigui , Yao Chunmei , Sun Duoxian , Dong Anjie
Published: September 2005

Methoxy poly(ethylene glycol)‐b‐poly(L‐lactic acid) (MPELLA) was prepared by the melt polycondensation of methoxy poly(ethylene glycol) and L‐lactic acid. The structure and properties of MPELLA were characterized by IR, 1H‐NMR, differential scanning calorimetry, and wide‐angle X‐ray diffraction. To estimate its feasibility as a vehicle for paclitaxel, MPELLA nanoparticles were prepared by a self‐emulsification/solvent evaporation method. The paclitaxel‐loaded nanoparticles (PMTs) showed a spherical morphology with an inner core and an outer shell. The size, size distribution, and loading capacity of PMTs were also measured. The release kinetics of paclitaxel from PMTs in vitro was studied. The results show that paclitaxel can be effectively incorporated into MPELLA nanoparticles, which provide a delivery system for paclitaxel and other hydrophobic or toxic compounds. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2116–2122, 2005
Polyetherols from isocyanuric acid and propylene carbonate
Authors: Węglowska Elwira , Lubczak Jacek
Published: September 2005

A new method for the synthesis of polyetherols containing perhydro‐1,3,5‐triazine rings by the reaction of isocyanuric acid and an excess of propylene carbonate is described. The reaction was studied in the presence of various catalysts and with varying substrate molar ratios. The structures and physical properties of the products were also studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2130–2138, 2005
Synthesis and characterization of polyurethane anionomers
Authors: Matsunaga Katsuji , Nakagawa Kazuko , Sawai Satoshi , Sonoda Osamu , Tajima Masahiro , Yoshida Yasuhiko
Published: September 2005

Un‐ionized polyurethane was obtained by the reaction of an isocyanate‐terminated urethane prepolymer, which was synthesized from 4,4′‐diphenylmethane diisocyanate and poly(oxytetramethylene)‐α,ω‐glycol, with 2,2‐bis(hydroxymethyl)propionic acid. A carboxylate‐based polyurethane anionomer was then derived from the polyurethane by the use of the sodium, potassium, or magnesium salt of acetic acid as a neutralizer. The ionomerization resulted in the following changes in the characteristics of the polyurethane: (1) an increase in the tensile strength, (2) a decrease in the glass‐transition temperature, (3) an increase in the wettability and hygroscopicity with respect to water, and (4) susceptibility to thermal decomposition. A sulfonate‐based polyurethane was also synthesized for comparison with the carboxylate‐based polyurethane. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2144–2148, 2005
Radiation‐induced grafting of pentamethyl hindered amine light stabilizer 1,2,2,6,6‐pentamethyl‐4‐piperidinyl methacrylate onto polypropylene
Authors: Wang Huiliang
Published: September 2005

The γ‐radiation‐induced grafting of 1,2,2,6,6‐pentamethyl‐4‐piperidinyl methacrylate (PMPM) onto polypropylene (PP) was investigated with a simultaneous irradiation technique. The effects of the solvent, dose, monomer concentration, and photoinitiator on the grafting were investigated. The grafting was easier in a benzene solution than in chloroform and acetone solutions. The grafting percentage first increased almost linearly with the irradiation dose until 20 kGy and then increased slowly or remained constant. The grafting percentage increased with the monomer concentration until 1.1 mol/L. The grafting percentage was higher when the proper amount of benzophenone was added. The grafted samples were characterized with Fourier transform infrared spectroscopy and thermogravimetric analysis. Carbonyl groups were found on grafted PP samples, and the carbonyl index increased with the grafting percentage. Thermogravimetric analyses proved the existence of grafted materials on PP, and grafted PMPM thermally decomposed at a lower temperature than PP. The radiation resistance of PP with grafted PMPM was better than that of pristine PP. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2157–2164, 2005
Effects of the polybutadiene/poly(styrene‐co‐acrylonitrile) ratio in a polybutadiene‐g‐poly(styrene‐co‐acrylonitrile) impact modifier on the morphology and mechanical behavior of acrylonitrile–butadiene–styrene blends
Authors: Xu X. F. , Yang H. D. , Zhang H. X.
Published: September 2005

Polybutadiene‐g‐poly(styrene‐co‐acrylonitrile) (PB‐g‐SAN) impact modifiers with different polybutadiene (PB)/poly(styrene‐co‐acrylonitrile) (SAN) ratios ranging from 20.5/79.5 to 82.7/17.3 were synthesized by seeded emulsion polymerization. Acrylonitrile–butadiene–styrene (ABS) blends with a constant rubber concentration of 15 wt % were prepared by the blending of these PB‐g‐SAN copolymers and SAN resin. The influence of the PB/SAN ratio in the PB‐g‐SAN impact modifier on the mechanical behavior and phase morphology of ABS blends was investigated. The mechanical tests showed that the impact strength and yield strength of the ABS blends had their maximum values as the PB/SAN ratio in the PB‐g‐SAN copolymer increased. A dynamic mechanical analysis of the ABS blends showed that the glass‐transition temperature of the rubbery phase shifted to a lower temperature, the maximum loss peak height of the rubbery phase increased and then decreased, and the storage modulus of the ABS blends increased with an increase in the PB/SAN ratio in the PB‐g‐SAN impact modifier. The morphological results of the ABS blends showed that the dispersion of rubber particle in the matrix and its internal structure were influenced by the PB/SAN ratio in the PB‐g‐SAN impact modifiers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2165–2171, 2005