bluuebunny/crossref_metadata_2025 huggingface dataset:
New Persistent Heteroarylmethyl Radicals Resulting from the Intramolecular Addition of Aryloxymethyl Radicals onto Ketenimines. Synthesis of 2H‐1,4‐Benzoxazines.
Authors: Alajarin Mateo , Vidal Angel , Ortin Maria‐Mar , Bautista Delia
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of γ‐Substituted‐β‐(ethoxycarbonyl)allylsilanes via Peterson Olefination.
Authors: Suzuki Hideyuki , Ohta Soichi , Kuroda Chiaki
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Stereoselective Synthesis of D‐Desosamine (V) and Related Glycals via Tungsten‐Catalyzed Alkynol Cycloisomerization.
Authors: Davidson Mary H. , McDonald Frank E.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Highly Stereoselective Addition of Organozinc Reagents to Pentopyranose Derived Glycals: Effect of Protecting Group and Assignment of C‐Glycoside Stereochemistry.
Authors: Cook Matthew J. , Fletcher Matthew J. E. , Gray Diane , Lovell Peter J. , Gallagher Timothy
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Copper
Authors: Smith D. W.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Oxygen, Sulfur, Selenium and Tellurium
Authors: Skabara P. J.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Carbon, Silicon, Germanium, Tin and Lead
Authors: Parr J.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Vanadium, Niobium and Tantalum
Authors: Malito John
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
MFI: a Case Study of Zeolite Synthesis
Authors: Singh Ramsharan , Dutta Prabir K.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
New Self‐Assembling Nanomaterials: Development of Nanowires Based on the One‐Dimensional Metal Complexes
Authors: Kimizuka Nobuo
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of Heterocycles by Carbonylation of Acetylenic Compounds
Authors: Vizer Svetlana A. , Yerzhanov Kazbek B. , Al Quntar Abed Al Aziz , Dembitsky Valery M.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Dual Role of Nucleophiles in Palladium‐Catalyzed Heck, Stille, and Sonogashira Reactions
Authors: Jutand Anny
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Microwave‐Assisted Chemistry of Carbohydrates
Authors: Corsaro Antonino , Chiacchio Ugo , Pistara Venerando , Romeo Giovanni
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
The Development of the Intramolecular Asymmetric Heck Reaction
Authors: Guiry Patrick J. , Kiely Denis
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Isopolyhalomethanes: Their Formation, Structures, Properties and Cyclopropanation Reactions with Olefins
Authors: Phillips D. L. , Fang W.‐H. , Zheng X. , Li Y.‐L. , Wang D. , Kwok W. M.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
The Theory of Formation of Surface Complexes and Its Application to the Description of Multicomponent Dynamic Sorption Systems
Authors: Hoell W. H. , Kalinitchev A. I.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Application of Amperometric Biosensors to the Determination of Vitamins and α‐Amino Acids
Authors: Sanz Alaejos Maite , Garcia Montelongo Francisco Jorge
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Local lymph node involvement does not predict poor outcome in pediatric renal cell carcinoma
Authors: Geller James I. , Dome Jeffrey S.
Published: August 2004

BACKGROUND

Local lymph node involvement in adults with renal cell carcinoma (RCC) is associated with poor outcome. The prognostic significance of local lymph node involvement in children with RCC has not been studied systematically.

METHODS

A retrospective review of patients treated at St Jude Children's Research Hospital (Memphis, TN) and an extensive review of the medical literature were undertaken to evaluate the prognostic significance of local lymph node involvement in pediatric RCC.

RESULTS

Thirteen patients with the diagnosis of RCC were treated at St. Jude since the hospital's inception in 1962. Four patients presented with lymph node‐positive, distant metastasis‐negative (N+M0) disease, and all 4 remain disease free after resection without adjuvant therapy (follow‐up duration, 2–9 years). A systematic review of the literature including 243 pediatric patients with RCC revealed stage‐specific survival rates of 92.5%, 84.6%, 72.7%, and 12.7% for Stage I–IV disease, respectively. Of 58 children with N+M0 RCC for whom outcome data were available, 42 (72.4%) were alive without disease at last follow‐up. Among patients whose therapy could be discerned, those who received no adjuvant therapy fared as well (15 of 16 alive) as those who received various adjuvant treatments (22 of 31 alive).

CONCLUSIONS

Children with lymph node–positive RCC in the absence of distant metastatic disease had a relatively favorable long‐term prognosis, with survival rate nearly triple those of adult historical controls. Until highly effective therapies for RCC are identified, these children should not be exposed to adjuvant treatment. Further investigation of the biologic differences between adult and pediatric RCC is warranted. Cancer 2004. © 2004 American Cancer Society.
Establishing a germ cell origin for metastatic tumors using OCT4 immunohistochemistry
Authors: Cheng Liang
Published: August 2004

BACKGROUND

There are diverse morphologic manifestations of metastatic tumors. The determination of tumor origin is critical for patient management, and it is especially important when the differential diagnosis includes metastatic germ cell tumor, which is a highly treatable condition. OCT4 is a nuclear transcription factor that is expressed in pluripotent embryonic germ cells. In this study, the author sought to determine the usefulness of OCT4 immunohistochemistry in the diagnosis of metastatic germ cell tumors.

METHODS.

Sixty‐two retroperitoneal lymph node dissection specimens from patients with histories of testicular germ cell tumors were stained using the antibodies against OCT4. In addition, 84 metastatic, nongerm cell lesions from men with known primary tumors were studied in parallel for OCT4 immunohistochemistry.

RESULTS.

All embryonal carcinoma components (n = 29 specimens) and seminoma components (n = 18 specimens) from retroperitoneal lymph node dissection specimens showed strong, intense, diffuse nuclear staining for OCT4. Yolk sac tumors (n = 12 tumors), choriocarcinomas (n = 4 tumors), mature teratomas (n = 16 tumors), and primitive neuroectodermal tumors (n = 5 tumors) were negative for OCT4 staining. Metastatic, nonsmall cell carcinomas from the lung (n = 14 tumors), colon (n = 12 tumors), stomach (n = 5 tumors), pancreas (n = 7 tumors), prostate (n = 12 tumors), kidney (n = 3 tumors), and urinary bladder (n = 15 tumors) all were found to be negative immunohistochemically for OCT4, as were metastatic small cell carcinomas (n = 4 tumors) and metastatic melanomas (n = 7 tumors). In addition, malignant lymphomas (n = 5 tumors) also were negative for OCT4.

CONCLUSIONS.

Immunohistochemical detection of OCT4 is highly sensitive and specific for the diagnosis of seminoma and embryonal carcinoma metastatic from the testis. Establishing germ cell origin for metastatic tumors has important implications for assessing patient prognosis and treatment options. Cancer 2004 © 2004 American Cancer Society.
Structural and Magnetic Properties of Two Carboxylato‐Bridged Manganese(II) Complexes with N‐Donor Coligands
Authors: Konar Sanjit , Manna Subal Chandra , Zangrando Ennio , Mallah Talal , Ribas Joan , Chaudhuri Nirmalendu Ray
Published: August 2004

Two polymeric MnII complexes, [(m‐phth)(Mn)(bpp)2]·0.5H2O (1) and [(mal)2(Mn)2(H2O)2(hmt)] (2) [mal = malonate; hmt = hexamethylenetetramine; bpp = 1,3‐bis(4‐pyridyl)propane; m‐phth = 1,3‐benzenedicarboxylate] have been synthesized. Complex 1 consists of 1D chains (with monocoordinated bpp) that are held together to form a 2D extended network of hydrogen bonding between lattice water molecules and uncoordinated bpp donors. Variable‐temperature magnetic susceptibility data of the complex have been fitted applying the formula used for dinuclear complexes of MnII ions, considering interdimer interactions (J′). The following parameters were obtained from the best fit: J = −0.88 ± 0.02 cm−1, J′ = −0.1 cm−1 and g = 1.99 ± 0.01. The agreement factor R = Σ(χmTobsd. − χmTcalcd.)2/Σ(χmTcalcd.)2 is 1.110−5. Complex 2 is a 3D polymeric network where syn/anti‐bridging malonate ligands and MnII centers are assembled in the form of [Mn(H2O)(mal)]n layers, which are further connected by hexamethylenetetramine. The magnetic data have been fitted considering the complex as a pseudo‐two‐dimensional sheet of MnII cations and malonate anions since the coupling through the hexamethylenetetramine ligand is almost zero. We have followed two approaches for fitting the data, (a) through the expansion series of Line’s equation for the S = 5/2 antiferromagnetic quadratic layer and (b) by using the equation based on an infinite 2D square lattice composed of isotropically coupled classical spin S = 5/2. Both approaches result in excellent theoretical fits and similar J values of −0.24 cm−1 and −0.21 cm−1 for the Line’s and Curély equations, respectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
A Novel Hybrid Supramolecular Network Assembled from Perfect π−π Stacking of an Anionic Inorganic Layer and a Cationic Hydronium‐Ion‐Mediated Organic Layer
Authors: Luo Tzuoo‐Tsair , Liu Yen‐Hsiang , Tsai Hui‐Lien , Su Chan‐Cheng , Ueng Chuen‐Her , Lu Kuang‐Lieh
Published: August 2004

The synthesis and characterization of a three‐dimensional inorganic‐organic hybrid network [{Cu2(CA)3}{(H3O)2(phz)3}·G]n (1; H2CA = chloranilic acid, phz = phenazine; G = 2CH3COCH3·2H2O) is described. The crystal structure of 1 shows that the 3D network assembly is based on a combination of two types of grid‐building sub‐units of (6,3) topology: an anionic metal‐organic coordination honeycomb grid, and a cationic hydronium‐ion‐mediated organic honeycomb grid. The inorganic and organic honeycomb nets are perfectly π−π‐stacked, creating an infinite number of open‐end channels (channel size about 8 Å in diameter). The solid framework of 1 retains its rigidity upon removal of the guest molecules under high vacuum to form compound [{Cu2(CA)3}{(H3O)2(phz)3}]n (2) as revealed by a single‐crystal X‐ray diffraction analysis. Compounds [{M2(CA)3}{(H3O)2(phz)3}·G]n (M = Cd, 3; M = Zn, 4; M = Co, 5; G = 2CH3COCH3·2H2O) were also prepared and characterized as isostructures of 1 [crystal data for 1: Cu2(CA)3(H3O)2(phz)3·G, trigonal, space group P$\bar 3$
1m, formula mass = 1478.86, a = 13.7593(2) Å, c = 9.1869(2) Å, V = 1506.22(5) Å3, Z = 1; crystal data for 2: Cu2(CA)3(H3O)2(phz)3, trigonal, space group P$\bar 3$
1m, formula mass = 1326.62, a = 13.7565(4) Å, c = 9.1544(5) Å, V = 1500.3(1) Å3, Z = 1]. The magnetic‐exchange coupling between the copper centers for compound 1 was analyzed on the basis of the Curie−Weiss expression and a dinuclear magnetic model. The negative values of the Weiss constant and the magnetic‐exchange coupling constant indicate an antiferromagnetic interaction between the copper centers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Adolescents' experiences of inpatient treatment for anorexia nervosa
Authors: Colton Anna , Pistrang Nancy
Published: August 2004

Objective

This qualitative study aimed to provide a detailed description of how adolescents experience inpatient treatment for anorexia nervosa.

Method

Semi‐structured interviews were conducted with 19 young women in two inpatient eating disorder units. Interpretative phenomenological analysis was used to analyse the data.

Results

Participants expressed both positive and negative views of their inpatient treatment; their accounts were characterized by conflicts and dilemmas. Five themes were identified: (1) What is this illness that I have? (2) Do I want to get well? (3) Being with others: support vs distress; (4) Being an individual vs just another anorexic; and (5) Collaborating in treatment vs being treated.

Discussion

The stages of change model provides a useful framework for understanding the experience of inpatient treatment. The findings suggest several ways in which inpatient units might more effectively meet the needs of adolescents with anorexia. Copyright © 2004 John Wiley & Sons, Ltd and Eating Disorders Association.
Purpose, context, and synthesis: Can we avoid relativism?
Authors: Petrie Hugh G.
Published: August 2004

Perceptual control theory of human behavior suggests to evaluators how to reach warranted syntheses legitimately even though their judgments are inevitably dependent on context and the purposes of the stakeholders.
Reasoning in evaluation: Challenges for the practitioner
Authors: Rog Debra J.
Published: August 2004

The reasoning process should be salient to the evaluator throughout the course of an evaluation.
Evaluating the 1992 and 1993 community integrated service systems projects
Authors: Roberts Richard N. , Wasik Barbara H.
Published: August 2004

The federal evaluation of forty‐one Community Integrated Service Systems projects is described, focusing on issues in conducting a national, cross‐site evaluation and the findings of the implementation study of the first two years of the initiative.
Evaluating a statewide school‐linked services initiative: California's Healthy Start
Authors: Wagner Mary M. , Gomby Deanna S.
Published: August 2004

The policy, political, fiscal, and logistic contexts of California's Healthy Start initiative are described, along with the choices made in accommodating those contexts in the evaluation design and implementation.
Seasonal forecasting of the Ethiopian summer rains
Authors: Gissila T. , Black E. , Grimes D. I. F. , Slingo J. M.
Published: August 2004

We present a new seasonal forecasting model for the June–September rains in Ethiopia. It has previously been found that the total June–September rainfall over the whole country is difficult to predict using statistical methods. A detailed study of all available data shows the rainfall seasonality varies greatly from one region to another, which would explain why the total June–September rainfall over all regions is a difficult property to forecast. In addition, the correlation between rainfall and the southern oscillation index varies spatially, with a strong teleconnection present only in some regions. This study accounts for the spatial variability in rainfall by grouping the rain gauge stations into four geographical clusters based on seasonality and cross‐correlation of rainfall anomalies. Linear regression equations are then developed separately for each cluster. The variables we use for the regressions are sea‐surface temperature anomalies in the preceding March, April and May of the tropical western Indian Ocean, the tropical eastern Indian Ocean, and Niño3.4. Formal skill testing of the equations shows that the new forecasting scheme is more effective in central western Ethiopia than either climatology or persistence—the methods currently used by the Ethiopian National Meteorological Services Agency. Copyright © 2004 Royal Meteorological Society
Climate impacts on Indian agriculture
Authors: Krishna Kumar K. , Rupa Kumar K. , Ashrit R. G. , Deshpande N. R. , Hansen J. W.
Published: August 2004

Agriculture (arguably the backbone of India's economy) is highly dependent on the spatial and temporal distribution of monsoon rainfall. This paper presents an analysis of crop–climate relationships for India, using historic production statistics for major crops (rice, wheat, sorghum, groundnut and sugarcane) and for aggregate food grain, cereal, pulses and oilseed production. Correlation analysis provides an indication of the influence of monsoon rainfall and some of its potential predictors (Pacific and Indian Ocean sea‐surface temperatures, Darwin sea‐level pressure) on crop production. All‐India annual total production (except sorghum and sugarcane), and production in the monsoon (except sorghum) and post‐monsoon seasons (except rice and sorghum) were significantly correlated to all‐India summer monsoon rainfall. Monsoon season crops (except sorghum) were strongly associated with the three potential monsoon predictors. Results using state‐level crop production statistics and subdivisional monsoon rainfall were generally consistent with the all‐India results, but demonstrated some surprising spatial variations. Whereas the impact of subdivisional monsoon rainfall is strong in most of the country, the influence of concurrent predictors related to El Niño–southern oscillation and the Indian Ocean sea‐surface temperatures at a long lead time seem greatest in the western to central peninsula. Copyright © 2004 Royal Meteorological Society
Fabrication and Characterization of Soluble Multi‐Walled Carbon Nanotubes Reinforced P(MMA‐co‐EMA) Composites
Authors: Yang Junwei , Hu Jianhua , Wang Changchun , Qin Yujun , Guo Zhixin
Published: August 2004

Summary: Soluble multi‐walled carbon nanotubes (s‐MWNTs), obtained via amidation reaction of octadecylamine with purified multi‐walled carbon nanotubes (p‐MWNTs), were solution‐mixed with P(MMA‐co‐EMA) at various loadings. Compared to the p‐MWNTs/P(MMA‐co‐EMA) composites, the s‐MWNTs/P(MMA‐co‐EMA) composites showed great improvement both in Young's modulus and tensile strength. With the addition of 10 wt.‐% s‐MWNTs, the Young's modulus and tensile strength of s‐MWNTs/P(MMA‐co‐EMA) composite have 135% and 49% increase over the pure P(MMA‐co‐EMA), respectively, and a 9.2% increase in Young's modulus and 12.8% increase in tensile strength over that of 10 wt.‐% p‐MWNTs composite. With the increase of MWNTs content, the Tg increases from 89 to 106 °C. SEM studies show that the s‐MWNTs are well dispersed in the polymer matrix. Good dispersion of s‐MWNTs in polymer matrix and great interfacial bonding between s‐MWNTs and P(MMA‐co‐EMA) may be the key reason for the improvement of the mechanical properties.

Stress‐strain curves of the MWNTs and P(MMA‐co‐EMA) composites.

magnified image

Stress‐strain curves of the MWNTs and P(MMA‐co‐EMA) composites.
Population Balance Model for Miniemulsion Polymerization, 2
Authors: Sood Ashwini , Awasthi Shailendra K.
Published: August 2004

Summary: The predictions of the model developed in Part 1 of this series are compared with experimental values taken from literature. Initially, the method of solution of the population balance equation and the simulation algorithm are given. Various radical entry mechanisms are discussed in adequate detail. Plausible arguments are given to identify the correct radical entry mechanism. An expression to evaluate the radical exit coefficient is given. Model predictions of a number of variables are discussed. These include average number of radicals per particle, particle phase monomer volume fraction, average number of radicals averaged over all particles, monomer volume fraction averaged over all particles, variation of nucleation rate, variation of fraction of droplets nucleated, variation of average diameter, variation of standard deviation, variation of polydispersity index, and development of particle size distribution with time. Finally, model predictions for the variation of conversion with time for five different initiator concentrations, number average diameter, standard deviation and full distribution are compared with experimental values.

Variation in the average number of radicals per particle with time, at different collocation points.

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Variation in the average number of radicals per particle with time, at different collocation points.
T lymphocytes and food allergy
Authors: Bohle Barbara
Published: August 2004

Food allergy is a hypersensitivity reaction to normally harmless substances and involves humoral immune responses, mediated by immunoglobulin (IgE) synthesized by B lymphocytes, and cellular immune responses mediated by T lymphocytes. An IgE‐mediated mechanism leads to clinical symptoms occurring immediately after food ingestion, e. g., “the oral allergy syndrome”. For delayed reactions involving the gastrointestinal tract or the skin, the underlying immune mechanisms are less clear. In order to elucidate the cellular response to food allergens, human allergen‐specific T cell cultures generated in vitro represent helpful tools. The majority of food allergen‐specific CD4+ T lymphocytes isolated from food‐allergic individuals was found to synthesize high levels of IL‐4 and IL‐13, two cytokines required for initiation of IgE synthesis. Due to selective homing profiles, food‐specific T cells seem also to be involved in defining the target organ of the allergic inflammation. Recent data provide evidence that in addition to IgE‐mediated inflammation, food allergen‐specific T lymphocytes may also cause inflammatory responses independently of IgE‐mediated mechanisms.
Convergence analysis of the streamline diffusion and discontinuous Galerkin methods for the Vlasov‐Fokker‐Planck system
Authors: Asadzadeh M. , Kowalczyk P.
Published: August 2004

We prove stability estimates and derive optimal convergence rates for the streamline diffusion and discontinuous Galerkin finite element methods for discretization of the multi‐dimensional Vlasov‐Fokker‐Planck system. The focus is on the theoretical aspects, where we deal with construction and convergence analysis of the discretization schemes. Some related special cases are implemented in M. Asadzadeh [Appl Comput Meth 1(2) (2002), 158–175] and M. Asadzadeh and A. Sopasakis [Comput Meth Appl Mech Eng 191(41–42) (2002), 4641–4661]. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005
Convergence of V‐ and F‐cycle multigrid methods for the biharmonic problem using the Hsieh‐Clough‐Tocher element
Authors: Zhao Jie
Published: August 2004

Multigrid V‐ and F‐cycle algorithms for the biharmonic problem using the H‐C‐T element are studied in the article. We show that the contraction numbers can be uniformly improved by increasing the number of smoothing steps. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005
Characterisation of estrone–nucleic acid adducts formed by reaction of 3,4‐estrone‐o‐quinone with 2′‐deoxynucleosides/deoxynucleotides using capillary liquid chromatography/electrospray ionization mass spectrometry
Authors: Borges Crispina , Lemière Filip , Embrechts Jan , Van Dongen Walter , Esmans Eddy L.
Published: August 2004

Xenobiotic and endobiotic molecules can react with DNA leading to formation of so‐called DNA adducts. This modified DNA can be repaired enzymatically, but, if not, these modifications are believed to be responsible for the initiation of carcinogenic processes. Hence, we studied the interaction of 2′‐deoxynucleosides and 2′‐deoxynucleotides with 3,4‐estronequinone (3,4‐E1Q), a metabolite of estrone (E1) and a supposed carcinogen. These estrone–nucleic acid adducts were analysed by capillary liquid chromatography (CapLC) coupled to electrospray ionization mass spectrometry (ESI‐MS). Knowledge of their behaviour from in vitro studies is a prerequisite for detecting adducts in in vivo studies. Our initial attempts to synthesise nucleos(t)ide adducts of 3,4‐E1Q in an aprotic solvent (dimethylformamide) yielded no adducts. However, under acidic aqueous conditions, adducts were obtained. With dGuo, a dGuo adduct was found in addition to a Gua adduct. Earlier publications on adduct formation in protic solvents failed to report formation of any adduct with dAdo. A N3‐Ade adduct was reported upon reaction of 3,4‐E1Q with Ade base and with DNA. With dAdo, we obtained two nucleoside adducts and six Ade adducts due to loss of 2′‐deoxyribose. Thus, contrary to general belief that only 2,3‐E1Q can form stable adducts, we showed formation of substantial amounts of intact DNA adducts with 3,4‐E1Q in addition to deglycosylated adducts. Adducts were also obtained with dGMP and dAMP, but no phosphate alkylation was found. Adducts of dCyd, dCMP, dThd, and dTMP were not detected. Using chromatographic‐MS data a structural relationship between the 2′‐deoxynucleoside, 2′‐deoxynucleotide and base adducts was found in the various reaction mixtures. The adducts of dGuo and dGMP reaction mixtures were alkylated at the same N7‐position of the nucleobase, as indicated by the occurrence of a rapid deglycosylation reaction. In dAdo and dAMP reaction mixtures, 14 adducts were detected; their relationships from the LC and MS data reduced the number of structures to six adenine base alkylated adducts with respect to alkylation between N1, N3, N7 and/or N6 in the adenine and C1, C2 and/or C6 in 3,4‐E1Q. We could infer, in addition, whether they had an A ring attachment or a C6 attachment on the estrone moiety. Copyright © 2004 John Wiley & Sons, Ltd.
Chloride‐enhanced atmospheric pressure chemical ionization mass spectrometry of polychlorinated n‐alkanes
Authors: Zencak Zdenek , Oehme Michael
Published: August 2004

The use of high‐performance liquid chromatography combined with chloride‐enhanced atmospheric pressure chemical ionization for the determination of polychlorinated n‐alkanes (PCAs, also called chlorinated paraffins or CPs) is described as an alternative to gas chromatographic methods. Atmospheric pressure chemical ionization in the negative ion mode formed exclusively [M+Cl]− adduct ions and suppressed fragmentation when a chlorinated solvent was added. Limits of detection were 1–2 ng/μL for technical PCA mixtures. Response factors for single short‐chain PCA homologues with different degrees of chlorination varied by not more than a factor of 6.5. The developed method was applied for the determination of the composition of technical PCA mixtures as well as for the analysis of PCAs in household commodities. Medium‐chain PCAs were found in paint samples at concentrations of 8.2–11.5% (w/w), compared with 7.4–11.5% obtained by gas chromatography combined with electron ionization tandem mass spectrometry. Copyright © 2004 John Wiley & Sons, Ltd.
Doppler study of the umbilical and fetal middle cerebral arteries in women with gestational diabetes mellitus
Authors: Leung W. C. , Lam H. , Lee C. P. , Lao T. T.
Published: August 2004

Objective

To investigate the correlation between Doppler parameters in the umbilical and fetal middle cerebral arteries and pregnancy outcome in women with gestational diabetes mellitus (GDM).

Methods

A prospective study was performed on 169 singleton GDM pregnancies in a university teaching hospital from January to December 2002. Umbilical artery (UA) pulsatility index (PI) and middle cerebral artery (MCA) PI and peak systolic velocity (Vmax) were measured every 4 weeks until delivery from the time of diagnosis of GDM. The pregnancy outcome was obtained from the hospital database. Using linear or quadratic regression, lines of best fit were drawn to compare the Doppler measurements between the two groups with normal and abnormal pregnancy outcomes.

Results

One hundred and thirty‐eight women with known pregnancy outcome completed the study. A total of 305 Doppler examinations were performed with one to four examinations for each woman. Thirty‐eight women (27.5%) had one or more abnormal pregnancy outcomes: placental abruption, pre‐eclampsia, preterm delivery, small‐for‐gestational age (SGA) infants, low Apgar scores, neonatal jaundice requiring treatment, sepsis, birth trauma, meconium aspiration syndrome, respiratory and neurological complications. There was extensive overlap of the UA‐PI, MCA‐PI and MCA‐Vmax measurements between the two groups.

Conclusion

A Doppler study of the UA‐PI, MCA‐PI and MCA‐Vmax was not useful in the prediction of abnormal pregnancy outcome in GDM. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Self organization of the microtubule network. A diffusion based model
Authors: Robert Claudine , Bouchiba Mohamed , Robert Raoul , Margolis Robert L. , Job Didier
Published: August 2004

Summary— Microtubules form organized polymer networks in cells. Experimental evidence indicates that their mechanical properties do not play a significant role in the generation of such regular patterns. This spatial organization seems closely related to their dynamic behavior. Here we use mathematical modeling to define conditions under which microtubular dynamics result in self organization. We demonstrate that random diffusional processes can generate regular microtubule organizations under specified kinetic conditions which are found to be compatible with the known properties of tubulin polymers. The organizing forces are the tubulin concentration gradients which are generated by the polymer growth. The present analysis has been restricted to the phase of establishment of the microtubule network. The same conceptual framework, applied to steady state pattern maintenance suggests that the kinetic requirements for self organization might ultimately be responsible for such extraordinary in vivo microtubule dynamics, as the rapid turnover and “dynamic instability” of the interphase network.
Neurite outgrowth and proliferation of non‐neuronal cells on cryostat sections of adult muscle
Authors: Dussartre Christian , Koenig Jeanine
Published: August 2004

Summary— Rat spinal cord cells were cultured on cryostat sections of innervated and denervated muscle. Neurite outgrowth was greater on sections of denervated muscle, which therefore appeared to act on in vivo nerve regeneration. It seems that muscle sections were able to release into the culture medium factors that increase proliferation of fibroblasts. The muscle therefore appeared able to modulate its interaction with its environment by acting on different types of cells.
Presence of an immunologically‐defined class of peri‐Golgi vesicles in cultured mammalian cells
Authors: Mangeat Paul , Devilliers Ginette , Regaya Faouzi
Published: August 2004

Summary—

Immunsera of mice injected with clathrin‐depleted coated vesicle membranes, purified from rat liver, revealed a preferential labeling of some perinuclear structures by immunofluorescence microscopy on NRK cells. Subsequent production of 4 monoclonal antibodies was achieved. The antigen was strictly located in the Golgi area of the cell but was not an intrinsic element of the Golgi complex. The restricted location of the structures excluded these were lysosomes which appeared more dispersed in these cells. After nocodazole treatment the material was found dispersed in the cytoplasm. This provided a means of distinguishing the antigen from clathrin‐coated structures and Golgi intrinsic elements. Immunolocalization at the electron microscope level confirmed the data obtained at the light level. Some peroxidase reaction product was rarely associated with Golgi elements, but predominantly stained small neighboring Golgi vesicles (50 nm diameter), as well as tubulo‐elongated structures and some large (500 nm) irregular‐shaped vesicles. A 32 kDa molecular weight antigen was characterized by immunopurification from NRK cells metabolically labeled with 35S‐Met. This 32 kDa antigen appeared as part of a higher multimolecular membrane component of 300 kDa. A 170 kDa and a 70 kDa components were immunodetected in a semi‐purified membrane fraction from rat liver, demonstrating that the antigen was a minor but very antigenic contaminant of the coated vesicle preparation used as immunogen. In conclusion, the labeled peri‐Golgi structures may be part of the newly characterized trans‐Golgi network and/or of the reticular/vesicular endosomal, prelysosomal structure recently described.
Sperm penetration into immature mouse oocytes and nuclear changes during maturation: an EM study
Authors: Szöllösi Daniel , Szöllösi Maria S. , Czolowska Renata , Tarkowski Andrzej K.
Published: August 2004

Summary—

The ultrastructure of oocyte and sperm nuclei was studied in mouse ovarian oocytes inseminated in vitro and cultured for 1 1/2 and 3 h in a medium containing dbcAMP or lacking the maturation inhibitor. In oocytes blocked at the germinal vesicle (GV) stage, certains maturation‐linked changes were noted. Sperm apposition and sperm‐oocyte fusion were similar to that during fertilization of ovulated oocytes. The sperm nucleus and its nuclear envelope remained intact after penetrating into the ovarian oocyte. One and a half h after removal of the drug (time 0 of maturation) the germinal vesicle (GV) and sperm nucleus remained intact. In oocytes maturing for 3 h, the nuclear envelopes of the GV and sperm nucleus had fragmented. The NE of the oocyte formed quadruple membranes while the NE of the sperm remained as flat vesicles. Oocyte chromatin condensed to form chromosomes, whereas at the same time the sperm chromatin was in the process of decondensation and was surrouded by fragments of the sperm NE. The sperm chromatin, composed of DNA complexed with protamines, consisted of thin fibrils; the individual fibrils measured 3.8 nm in diameter. Near the penetrated spermatozoa only occasional Mts were detected which were not related to the proximal centriole which was recognizable in the neck‐piece of the flagellum. Thus in mouse oocytes the introduced sperm centriole is not capable of behaving as a centrosome and organizing microtubules in the form of an aster.
Sodium butyrate inhibits c‐myc and stimulates c‐fos expression in all the steps of the cell‐cycle in hepatoma tissue cultured cells
Authors: Tichonicky Lydie , Kruh Jacques , Defer Nicole
Published: August 2004

Summary—

Soduim butyrate decreases the c‐myc mRNA and increases the c‐fos transcript level in HTC cells. This effect is independent of the cell‐cycle phase. Actinomycin D suppresses the effect on c‐fos. Cycloheximide increases both mRNA levels. Sodium butyrate suppresses the effect on c‐myc and potentializes the effect on c‐fos mRNAs. This suggests that sodium butyrate acts at the transcriptional level and that its effect does not result from the arrest of the cells at the G1 phase.
Confocal microscopy as a tool to reveal the tridimensional organization of intracellular lumens and intercellular cysts in a human colon adenocarcinoma cell line
Authors: Remy Lionel , Gorvel Jean‐Pierre , Jacquier Marie‐France , Rigal Alain , Davoust Jean
Published: August 2004

Summary— Adenocarcinoma cells often form intracellular lumens and intercellular cysts. In order to study the structural relationships between these lumens and the apical domain of normal enterocytes, we have applied electron microscopy and confocal microscopy to a cloned cell line derived from the human colon adenocarcinoma cell line LoVo which express a high number of intracellular lumens and intercellular cysts. Microvilli reminiscent of those detected in the brush border of small intestinal cells are formed in the two types of compartments. By immunofluorescence, we found that a 135 kDa membrane glycoprotein characterized by a monoclonal Ab and normally associated with the brush‐border of enterocytes is expressed at the surface of the intracellular lumens and intercellular cysts present in the adenocarcinoma cells. Comparison of fluorescence and reflection contrast micrographs obtained by confocal microscopy demonstrate the presence of spherical intracellular lumens in the juxtanuclear region of single cells, and of more complex shaped intercellular cysts located within clusters of cells. The later cells form junctional complexes limiting an apical plasma membrane domain in contact with the intercellular cyst. It is suggested that the intracellular lumens may represent the abortive form of an apical plasma membrane due to the lack of components required to establish epithelial cell contacts. As opposed to conventional fluorescence microscopy, confocal microscopy allows rapid inspection of the tridimensional organization of intracellular lumens and intercellular cysts even when they are located in cell multilayers.
Effects of cold shock treatment on amphibian oocytes: alteration of heterogenous nuclear RNP morphology
Authors: N'Da E´le´onore , Bonnanfant‐Jais Marie‐Louise , Moreau Nicole , Angelier Nicole
Published: August 2004

Summary— In cold‐stressed oocytes of Pleurodeles waltl, lampbrush chromosome lateral loops exhibited important structural modifications which were visualized under light microscopy. Electron microscopy study revealed that the RNP particles associated with growing transcripts in the matrix of these loops were 15 nm at 8°C compared to 30 nm at normal temperature (20°C); hnRNP isolated from cold‐stressed oocytes sedimented at 15 S in sucrose, while those from control oocytes sedimented at 30 S, as expected. However, under both normal and cold stress conditions, hnRNP possessed a buoyant density of 1.38 g/cm3 in CsCl, indicating that their typical RNA/protein ratio was maintained at 8°C. Our results demonstrate that cold stress affects the structure of hnRNP in amphibian oocytes.
Immunodetection of lipopolysaccharide in macrophages during the processing of non invasive Shigella dysenteriae
Authors: Dacosta Bruno , Ryter Antoinette , Mounier Joe¨lle , Sansonetti Philippe
Published: August 2004

Summary— The location of lipopolysaccharide (LPS) was studied by immunofluorescence and immunoelectron microscopy in macrophages infected with a non‐invasive Shigella dysenteriae 1 strain. Bacterial degradation began only 3 h after the end of infection. The first visible sign of degradation was detected by immunogold labelling at the level of LPS which detached from the bacterial surface and was transferred to the perinuclear lysosomes. After a few hours, it was found in small vesicles spread over the whole macrophage cytoplasm in which it remained visible for 72 h. These vesicles seemed to belong to a compartment in which slowly or non‐degradable compounds are stored. LPS separation from the bacterial surface was immediately followed by the degradation of the intrabacterial constituents. The long lag period observed before initiation of bacterial degradation was not due to a lack of phagosome acidification, since DAMP, a lysosomotropic drug was found in all phagosomes at the end of the ingestion period. Thefrequency of phagosome‐lysosome fusion was 30% for S dysenteriae and 72% for B subtilis used as a reference of high fusion frequency. The low frequency of fusion of S dysenteriae may play an important role in the survival of the virulent strains in macrophage by providing bacteria enough time to lyse the phagosome membrane before lysosome fusion occurs.
Relationship between vitamin D status and deposition of bound calcium in skeletal muscle of the rat
Authors: Toury Rene´e , Stelly Nicole , Boisonneau Elizabeth , Convert Monique , Dupuis Yvonne
Published: August 2004

Summary— The effects of vitamin D on the intramuscular distribution of total and bound calcium, phosphate and on available cytosolic calcium, were investigated in skeletal muscle. Total calcium and phosphorus were measured on ashed subcellular fractions of muscles from vitamin D‐repleted and vitamin D‐deprived rats. The variations in available calcium were followed by determining the activities of calcium‐sensitive enzymes in isolated cytosol. Bound‐calcium was revealed ultra‐microscopically by pyroantimonate. In vitamin D‐repleted muscles, the pyroantimonate method revealed specific areas of intense bound‐calcium deposition: the myofibrils, where they formed pronounced lines parallel to the Z‐bands. In vitamin D‐deficient muscles, the calcium‐pyroantimonate deposits appeared clearly reduced. This loss was accompanied by a marked reduction in total calcium and phosphorus in all the subcellular fractions, as compared to vitamin D‐repleted muscles. Unexpectedly, the activity of the Ca2+‐activated isocitrate‐dehydrogenase was increased in the cytosol, while that of the Ca2+‐inhibited pyruvate‐kinase decreased. Prolonged vitamin D‐administration to vitamin D‐repleted rats led to an intensification of calcium‐pyroantimonate deposits and a general increase in total calcium and phosphorus, but no change in the cytosolic Ca2+‐sensitive enzyme activities. Cessation of vitamin D‐administration to vitamin D‐repleted rats produced a regression of calcium‐pyroantimonate deposits, a general decrease of total calcium and phosphate levels, and stimulation of the Ca2+‐activated isocitrate‐dehydrogenase accompanied by lowering of the Ca2+‐inhibited pyruvate‐kinase. The results clearly indicate a correlation between vitamin D‐repletion and the total and bound calcium content of skeletal muscle. In addition, they demonstrate an apparent contradiction between the decrease of total and bound calcium, and the activities of cytosolic Ca2+ sensitive enzymes during vitamin D‐deprivation, which can only be explained by an increase in available calcium. It is suggested that vitamin D stimulates intramuscular mechanisms tending to lower available calcium by inactivating the cation via the formation of calcium chelates.
Ultrastructural patterns of the flagellar axoneme in the non‐motile part of the mole‐cricket sperm
Authors: Dallai Romano , Afzelius Björn A
Published: August 2004

Summary—

The mole‐cricket spermatozoon (Gryllotalpa gryllotalpa) has a motile anterior tail region and an immotile posterior region. The posterior portion appears stiff and its microtubular doublets and central singlet microtubules are swollen, apparently due to an excess of material within them. In particular, doublet number 6 is of an unusually large size. The general organization of the axoneme is also modified by a loss of dynein arms and spokes in the posterior portion. When studied by a fixation technique that involves tannic acid to outline the protein molecules and PA‐TCH‐Ag method for staining polysaccharides it could be seen that the microtubular doublets and accessory microtubules contain rounded globules surrounded by polysaccharides. The arrangement of protofilaments within the microtubular walls is visible both in the anterior tail region with normal doublets and in the posterior region with degenerated doublets.
A ground‐based model to study the effects of weightlessness on lymphocytes
Authors: Gmünder Felix K , Kiess Markus , Sonnefeld Gerry , Lee Juliet , Cogoli Augusto
Published: August 2004

Summary—

The mitogenic response of human lymphocytes was found to be markedly reduced in weightlessness conditions as compared to normal gravity. One possible explanation is that due to the non‐existent sedimentation in space the lymphocytes could not adhere and spread on a substratum. Thus, we investigated the effect of substratum adhesiveness on lymphocyte responsiveness by reducing and blocking cell adhesion with poly‐HEMA in a simple on‐ground system. Lymphocyte adhesiveness was assessed by measuring the proportion of non‐adhesive, slightly, and strongly adhesive 51Cr‐radiolabelled cells on uncoated and poly‐HEMA coated plastic. The amount of cell spreading on surfaces with varying adhesiveness was determined by measuring the area of cells. Cells grown on medium and thick poly‐HEMA films were rounded in shape. By contrast, on tissue culture plastic, they showed clear signs of spreading. The mitogenic response of lymphocytes grown on thick poly‐HEMA films was reduced by up to 68% of the control (tissue culture plastic). Interferon‐γ production was virtually nil when the cells were grown on the least adhesive substratum. These results show that activated lymphocytes need to anchor and spread prior to achieving an optimal proliferation response. We conclude that decreased lymphocyte adhesion could contribute to the depressed in vitro lymphocyte responsiveness found in the microgravity conditions of space flight.
Ultrastructure of E1 + 2 + 9 + 12 inversion breakpoints in Drosophila subobscura
Authors: Cuenca Juan Bautista , Saura Anja O , Sorsa Veikko , De Frutos Rosa
Published: August 2004

Summary—

The ultrastructure of the Drosophila subobscura chromosome regions around the breakpoints of the complex E1 + 2 + 9 + 12 gene arrangement was analyzed. This overlapping inversion is formed by the association of the E1, E2, E9, and E12 simple inversions. Ultrastructure of sections involving 58D/59A, 61C/D, 62D/63A, 64B/C, 67A/B, and 68B/C breakpoints on Est chromosomes were compared with the ultrastructure of sections involving 58D/68B, 62D/64C, 59A/63A, 64B/68C, 67B/61C, and 67A/61B breakpoints on E1 + 2 + 9 + 12 chromosomes. No detectable changes of structural organization on banding patterns induced by the E1 + 2 + 9 + 12 inversion were found. Ultrastructural analysis of the two E12 breakpoints has, however, facilitated the analysis of the left boundary of E12 inversion. Accordingly, we propose 61B/C as a new breakpoint instead of 61C/D.
Candida albicans— adriamycin interactions: ultrastructural and spectrofluorometric study of whole yeasts and spheroplasts
Authors: Bobichon Hélène , Bussy Véronique , Angiboust Jean‐François , Manfait Michel , Bouchet Philippe , Jardillier Jean‐Claude
Published: August 2004

Summary—

The occurrence of candidiasis in cancer patients who undergo chemotherapy requires the interrelation of Candida albicans and the antimitotic drug Adriamycin (ADM) which is well known as an intercalating agent. The whole yeasts were not affected by 2 h of contact with the drug at 10−4 M neither for their growth curve nor for their ultrastructure, despite the presence of free ADM on their surface. Spheroplasts displayed a delay in their growth and exhibited altered nucleoli with segregation of their granular and fibrillar components. The modified emission spectrum of ADM, determined by spectrofluorometry, corresponded neither to the free ADM nor to the DNA‐bound drug, but it could be related to a metabolite of the drug. The cell wall appeared to be one of the main sites for ADM resistance of Candida albicans in vitro.
Ferromagnetic isolation of endosomes: a novel method for subcellular fractionation of Xenopus oocytes
Authors: Bauer Alfred , Richter Hans‐Peter
Published: August 2004

Summary—

A novel method has been developed using ferric particles to label endosomes, and to achieve magnetic sorting of the various endocytic compartments involved in lipoprotein uptake into cells. Ferric particles conjugated to a receptor‐recognized ligand are bound to coated membrane pits and become internalized into the cytoplasm inside coated vesicles. After apparent fusion of the vesicles to tubular endosomes, the conjugates accumulate and finally discharge into multivesicular endosomes. Pulse‐chase experiments elucidate the pathway of internalized conjugates and allow both early compartments (pinosomes and tubular endosomes) and late compartments (multivesicular endosomes and storage organelles) to be selectively labelled. After ferroloading of the various transport compartments, the cells are homogenized and subcellularly fractionated. Sorting of labelled endosomes is performed by a specially designed “free‐flow” magnetic chamber.

Prophase I‐arrested oocytes of the toad Xenopus laevis are used as a model system for studying the transport pathway and the conversion of the yolk precursor vitellogenin. It is possible to follow the route of internalization of vitellogenin‐iron conjugates via coated pits, coated vesicles, uncoated vesicles, tubular endosomes, multivesicular endosomes, and light primordial yolk platelets. These endosomes shuttle the ferric particles together with the vitellogenin from oolemma to preformed heavy yolk organelles which are still growing. In addition, these various compartments can be isolated according to their function and subjected to electron microscopy and to gel electrophoresis for detailed characterization of their limiting membranes as well as their contents.