bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Some Chemical Transformations of (Z)‐ and (E)‐2‐Acetyl‐1‐ferrocenyl‐3‐methylbuta‐1,3‐dienes − A New Type of Cationic Cycloaddition
Authors: Klimova Elena I. , Klimova Tatiana , Stivalet Jose M. Méndez , Toledano Cecilio Alvarez , Toscano Ruben Alfredo , Ortega Simón Hernández , Ramírez Lena Ruíz , Bakinovsky Leon V. , García Marcos Martínez
Published: March 2004

Dehydration of (E)‐ and (Z)‐2‐acetyl‐1‐ferrocenyl‐3‐methylbut‐1‐en‐3‐ols gave the corresponding (E)‐ and (Z)‐2‐acetyl‐1‐ferrocenyl‐3‐methylbuta‐1,3‐dienes, which have a cross‐conjugated system of three double bonds. These heterotrienes readily afford the products of linear and cyclodimerization by following a cationic cyclodimerization mechanism; they also form Diels−Alder adducts with azodicarboxylic and maleic acid N‐phenylimides. The spatial structures of (E)‐2‐acetyl‐1‐ferrocenyl‐3‐methylbuta‐1,3‐diene, (E,E)‐1,5‐diferrocenyl‐2‐isopropenyl‐6‐isopropylidene‐3‐methyl‐1,3‐octadiene‐7‐one, and 7‐ferrocenyl‐4‐(ferrocenylmethylidene)‐8‐isopropylidene‐1,3,5‐trimethyl‐9‐oxabicyclo[3.3.1]non‐2‐ene were elucidated by X‐ray diffraction analyses of single crystals. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Novel and Rapid Synthetic Routes to A3B‐ and AB3‐Type 21‐Thiaporphyrins and Their Use in the Construction of Unsymmetrical Covalent and Non‐Covalent Porphyrin Arrays
Authors: Gupta Iti , Agarwal Neeraj , Ravikanth Mangalampalli
Published: March 2004

Novel and very simple methods were developed for the synthesis of 21‐thiaporphyrins having both one functional group (A3B) and three functional groups (AB3). These A3B‐ and AB3‐type 21‐thiaporphyrin building blocks were used to synthesize both covalently and non‐covalently linked unsymmetrical porphyrin arrays containing N3S and N4 porphyrin cores. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Molecular Library Obtained by Allene Insertion into the Pd−C Bond of Cyclopalladated Complexes: Biological and Pharmacological Evaluation
Authors: Sirlin Claude , Chengebroyen Jaganaiden , Konrath Renato , Ebeling Günther , Raad Imad , Dupont Jairton , Paschaki Marie , Kotzyba‐Hibert Florence , Harf‐Monteil Colette , Pfeffer Michel
Published: March 2004

A minilibrary of cationic N‐heterocycles has been prepared and evaluated. The potential for the preparation was a result of the high versatility of palladium‐mediated chemistry. The synthesis of the novel molecules was based on intramolecular quaternization of tertiary amine attached allylpalladium complexes. The steric and electronic factors of the reaction are discussed. The structures of the synthesized molecules made them candidates for precise biological and pharmacological evaluations. Of the various N‐heterocyclic compounds, 2,2‐dimethyl‐3‐methylenenaphtho[def]quinolizinium showed antibacterial activity at micromolar concentrations. This compound also proved to be a nanomolar competitive antagonist for the channel site of the nicotinic acetylcholine receptor. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Cover Picture: Formal Desymmetrization of the Diastereotopic Chains in Gemini Calcitriol Derivatives with Two Different Side Chains at C‐20 (Eur. J. Org. Chem. 8/2004)
Authors: Maehr Hubert , Uskokovic Milan R.
Published: March 2004

The cover picture shows symbolizes light that sustains life and the continuous evolution intimately connected to the critical role of vitamin D and its biomolecular receptor. It demonstrates the ability of mankind to supplement this evolutionary process by their inventions that contribute to health and well‐being. Details are discussed in the article by H. Maehr and M. R. Uskokovic on p. 1703 ff.
Electrochemical Characterization of the Self‐assembled Monolayer of 6‐Thioguanine on the Mercury Electrode
Authors: Arias Zoraida González , Muñiz Álvarez Jesús Luis , López Fonseca Juan Miguel
Published: March 2004

A self‐assembled monolayer (SAM) of 6‐thioguanine (6TG) was formed on the hanging mercury drop electrode, under open circuit potential, from 6TG solutions. The SAM has been characterized by cyclic voltammetry under both in situ and ex situ conditions and the experimental data reveal that the film is a densely packed structure of chemisorbed (mercury‐thiol) molecules. The presence of this SAM has no influence on the rate of outer‐sphere electrode reactions but strongly inhibits inner‐sphere processes. The electrode reaction involving the Fe(CN)$\rm{ {_{6}^{3-/4-}}}$ couple appears reversible in a hanging mercury drop electrode coated by the 6TG‐SAM.
Amperometric Study of Au‐Colloid Function on Xanthine Biosensor Based on Xanthine Oxidase Immobilized in Polypyrrole Layer
Authors: Liu Yingju , Nie Lihua , Tao Wenyan , Yao Shouzhuo
Published: March 2004

Four kinds of xanthine oxidase (XOD) based amperometric biosensors were fabricated and their analytical performances were compared. Polypyrrole (PPY)/XOD biosensor was constructed by electrochemical oxidation of pyrrole in the solution containing xanthine oxidase and pyrrole in this paper. Colloidal Au was then immobilized on the biosensor. On the other hand, electron mediator, Prussian Blue (PB), was deposited on the electrode before the immobilization of PPY/XOD to enhance electron‐transfer rate and current response. The results showed that PPY/XOD, PPY/XOD/Au‐colloid, PB/PPY/XOD and PB/PPY/XOD/Au‐colloid biosensors exhibit good response to xanthine in 1×10−6 M and 2×10−5 M and Michaelis‐Menten constants (Km) of these biosensors were 242.2, 113.4, 144.5, 43.2 μmol⋅L−1, respectively. The dependence of current responses with applied voltages was discussed, and different mechanisms of these biosensors were discussed. It has been found that colloidal Au can enhance the current response at the same concentration of xanthine solution and decrease the energy‐barrier of electron‐transfer reaction on the electrode.
Study on Electrochemiluminesce of Ru(bpy3)2+ Immobilized in a Titania Sol‐Gel Membrane
Authors: Zhuang Yafeng , Ju Huangxian
Published: March 2004

The immobilization of tris(2,2′‐bipyridyl)ruthenium(II), Ru(bpy)32+, at a glassy carbon electrode was achieved by entrapping the Ru(bpy)32+ in a vapor deposited titania sol‐gel membrane. The electrogenerated chemiluminescence (ECL) of the immobilized Ru(bpy)32+ was studied. The Ru(bpy)32+ modified electrode showed a fast ECL response to both oxalate and proline. The ECL intensity was linearly related to concentrations of oxalate and proline over the ranges from 20 to 700 μmol L−1 and 20 to 600 μmol L−1, respectively. The detection limits for oxalate and proline at 3σ were 5.0 μmol L−1 and 4.0 μmol L−1, respectively. This electrode possessed good precision and stability for oxalate and proline determinations. The electrogenerated chemiluminescence mechanism of proline system was discussed. This work provided a new way for the immobilization of Ru(bpy)32+ and the application of titania sol‐gel membrane in electrogenerated chemiluminescence.
Predictive control of seismic structures with semi‐active friction dampers
Authors: Lu Lyan‐Ywan
Published: March 2004

In this paper a predictive control method especially suitable for the control of semi‐active friction dampers is proposed. By keeping the adjustable slip force of a semi‐active friction damper slightly lower than the critical friction force, the method allows the damper to remain in its slip state throughout an earthquake of arbitrary intensity, so the energy dissipation capacity of the damper can be improved. The proposed method is formulated in a discrete‐time domain and cast in the form of direct output feedback for easy control implementation. The control algorithm is able to produce a continuous and smooth slip force for a friction damper and thus avoid exerting the high‐frequency structural response that usually exists in structures with conventional friction dampers. Using a numerical study, the control performance of a multiple degrees of freedom (DOF) structural system equipped with passive friction dampers and semi‐active dampers controlled by the proposed method are compared. The numerical case shows that by merely using a single semi‐active friction damper and a few sensors, the proposed method is able to achieve better acceleration reduction than the case using multiple passive dampers. Copyright © 2004 John Wiley & Sons, Ltd.
Chemical constituents of the essential oil of Lippia adoensis Hochst. ex Walp.
Authors: Kasali Adeleke A. , Ekundayo Olusegun , Winterhalter Peter , Koenig Wilfried A. , Eshilokun Adeolu O.
Published: March 2004

The composition of the essential oil of the leaves of Lippia adoensis Hochst. ex Walp. growing in Nigeria was determined by the use of GC and GC–MS. The leaf essential oil of L. adoensis predominantly comprised monoterpenoids (83.5%), of which linalool (26.1%), geraniol (19.0%) and 1,8‐cineole (17.4%) were the major constituents, while germacrene D (4.6%) was the main sesquiterpene identiﬁed in the oil. Copyright © 2004 John Wiley & Sons, Ltd.
Extraction of volatile compounds from Juniperus communis L. leaves with supercritical ﬂuid carbon dioxide: comparison with hydrodistillation
Authors: Pourmortazavi Seied Mahdi , Baghaee Parvin , Mirhosseini Mohammad Ali
Published: March 2004

Supercritical ﬂuid extraction (SFE) of volatile oil from Juniperus communis L. leaves using carbon dioxide was carried out under different conditions of pressure, temperature, modiﬁer content and dynamic extraction time. A total of 22 compounds have been determined in these extracts by GC–FID and identiﬁed by GC–MSD, while in the hydrodistilled oil only 11 components were identiﬁed and quantiﬁed. The proposed extraction method has been compared with the hydrodistillation method. SFE products were found to be markedly different from the corresponding hydrodistilled oil. A remarkable amount of β‐phellandrene was present in the hydrodistilled essential oil; also, the ratio of α‐pinene to 3‐carene in distilled oil was high in comparison with the supercritical carbon dioxide extracts. The results showed that under a pressure of 200 atm, a temperature of 45 °C and a dynamic extraction time of 30 min, supercritical ﬂuid extraction of limonene was more selective, and under a pressure of 350 atm, a temperature of 45 °C and a dynamic extraction time of 20 min, extraction was more selective for the α‐thoujone, which was not identiﬁed in the hydrodistilled oil. Better results have been obtained with the proposed method in terms of rapidity, cleanliness and the possibility of manipulating the composition of the extract. Copyright © 2004 John Wiley & Sons, Ltd.
Dividing Olig2‐expressing progenitor cells derived from ES cells
Authors: Xian Haiqing , Gottlieb David I.
Published: March 2004

G‐Olig2 is a knock‐in ES cell line with GFP inserted into the Olig2 gene so that ES cell‐derived neural cells that express Olig2 also express GFP. This tool allows visualization of the subset of cells that differentiate along the Olig2‐expressing pathway. By manipulating culture conditions, it is possible to induce Olig2 expression in rapidly dividing cells. These cells have many of the features of glial progenitor cells but, unlike other glial progenitors, are able to divide rapidly for at least 1 month while still expressing Olig2. Even after 1‐month expansion, the cells differentiate readily into astrocyte‐like and oligodendrocyte‐like cells when switched to serum‐containing medium. Cellular memory is the property whereby cells remain specified to a particular lineage or pathway while undergoing division. ES cell‐derived neural cells show cellular memory for a glial progenitor phenotype and thus provide a new and tractable model for this basic feature of neural development. © 2004 Wiley‐Liss, Inc.
Postoperative endocrine function in patients with surgically treated thyrotoxicosis
Authors: Sivanandan Ranjiv , Ng Lay Guat , Khin Lay Wai , Lim Teck Hock Dennis , Soo Khee Chee
Published: March 2004

Background.

Endocrine function after surgery for thyrotoxicosis is difficult to predict. The operative morbidity and long‐term thyroid function of patients surgically treated for thyrotoxicosis is presented, and factors postulated to affect long‐term function are correlated with outcome.

Methods.

The clinical records of 289 consecutive patients who underwent surgery for thyrotoxicosis were reviewed. Indications for surgery, intraoperative findings, postoperative complications, and endocrine status 1, 2, and 5 years after surgery were analyzed. Sex, age, duration of medical treatment, weight of thyroid removed and preserved, and antimicrosomal/antithyroglobulin antibody status were correlated with outcome 5 years after surgery.

Results.

The incidence of permanent recurrent laryngeal nerve injury and hypocalcemia were 0.7% and 1.7%. The cumulative hypothyroid and hyperthyroid rates for the first, second, and fifth postoperative years were 13.8% and 3.5%, 14.5% and 4.8%, and 15.6% and 8.0%. All the prognostic variables analyzed did not achieve a significant correlation with outcome at 5 years by univariate and multivariate age‐ and sex‐adjusted relative risk.

Conclusions.

Failure from hypothyroidism develops early; recurrent hyperthyroidism increases with the number of years of follow‐up. Patients undergoing subtotal thyroidectomy warrant long‐term follow‐up because of the inability to accurately predict postoperative function with consistently reliable prognostic factors. © 2004 Wiley Periodicals, Inc. Head Neck 26: 331–337, 2004
Routine inclusion of level IV in neck dissection for squamous cell carcinoma of the larynx: Is it justified?
Authors: Khafif Avi , Fliss Dan M. , Gil Ziv , Medina Jesus E.
Published: March 2004

Background.

Dissection of levels II–IV as part of an elective or therapeutic neck dissection is common practice during laryngectomy for laryngeal squamous cell carcinoma (SCC). The necessity of routine dissection at level IV has recently been questioned. The purpose of this study was to find the incidence of level IV metastases in patients with transglottic and supraglottic SCC who underwent neck dissections.

Methods.

The charts of 71 suitable patients were reviewed. Forty‐two had supraglottic primary cancers, and 29 had transglottic primary tumors. Levels II–IV had been removed in them all, and their neck specimens were marked according to the levels of the neck. The surgical specimens were pathologically diagnosed.

Results.

Of 43 patients who underwent elective lateral neck dissection, the only one (2.3%) with level IV metastases also showed metastases at level II. Nine (32%) of the other 28 patients with clinical adenopathy had level IV metastases.

Conclusions.

Dissection of level IV as part of a therapeutic neck dissection for supraglottic and transglottic SCC is recommended for patients with clinically enlarged lymph nodes, but its necessity in the absence of detectable adenopathy is challenged. © 2004 Wiley Periodicals, Inc. Head Neck 26: 309–312, 2004
Severe hyperthyroidism induces mitochondria-mediated apoptosis in rat liver
Authors: Upadhyay Geeta , Singh Rajesh , Kumar Ashok , Kumar Sanjeev , Kapoor Amit , Godbole Madan M.
Published: March 2004

Thyrotoxicosis may be associated with a variety of abnormalities of liver function. The pathogenesis of hepatic dysfunction in thyrotoxicosis is unknown, but has been attributed to mitochondrial dysfunction. We studied the effect of altered thyroid function on the apoptotic index in rat liver. Extensive DNA fragmentation and significantly increased caspase-3 activity (P < .001) and caspase-9 activation (P < .005) were observed in hyperthyroid rat liver; cell death by apoptosis was confirmed. In hyperthyroid rat liver, 60% of mitochondria exhibited disruption of their outer membranes and a decrease in the number of cristae. These findings, along with significant translocation of cytochrome c and second mitochondria-derived activator of caspases to cytosol (P < .005), suggest activation of a mitochondrial-mediated pathway. However, no change in the expression levels of Bcl-2, Bax, and Bcl-xL were found in hyperthyroidism. For in vitro experiments, rat liver mitochondria were isolated and purified in sucrose density gradients and were treated with triiodothyronine (T3; 2-8 μM). T3 treatment resulted in an abrupt increase in mitochondrial permeability transition. Using a cell-free apoptosis system, the apoptogenic nature of proteins released from mitochondria was confirmed by observing changes in nuclear morphologic features and DNA fragmentation. Proteins released by 6 μM T3 contained significantly increased amounts of cytochrome c (P < .01) and induced apoptotic changes in 67% of nuclei. In conclusion, using in vivo and in vitro approaches, we provide evidence that excess T3 causes liver dysfunction by inducing apoptosis, as a result of activation of a mitochondria-dependent pathway. Thus, the results of this study provide an explanation for liver dysfunction associated with hyperthyroidism. (Hepatology 2004;39:1120-1130.)
Treatment of pyogenic liver abscess: Prospective randomized comparison of catheter drainage and needle aspiration
Authors: Yu Simon C.H. , Ho Simon S.M. , Lau Wan Y. , Yeung Deacons T.K. , Yuen Edmund H.Y. , Lee Paul S.F. , Metreweli Constantine
Published: March 2004

This study aims to compare the therapeutic effectiveness of continuous catheter drainage versus intermittent needle aspiration in the percutaneous treatment of pyogenic liver abscesses. Over a 5-year period, 64 consecutive patients with pyogenic liver abscess were treated with intravenous antibiotics (ampicillin, cefuroxime, and metronidazole) and randomized into two percutaneous treatment groups: continuous catheter drainage (with an 8F multi-sidehole pigtail catheter); and intermittent needle aspiration (18G disposable trocar needle). There was no statistically significant difference between the two groups regarding patient demographics, underlying coexisting disease, abscess size, abscess number, number of loculation of abscess, the presenting clinical symptoms such as fever, abdominal pain, and pretreatment liver function test. Although not statistically significant, the duration of intravenous antibiotics treatment before percutaneous treatment was longer with the catheter group, and the change of antibiotics after the sensitivity test was more frequent with the needle group. The needle group was associated with a higher treatment success rate, a shorter duration of hospital stay, and a lower mortality rate, although this did not reach statistical significance. In conclusion, this study suggests that intermittent needle aspiration is probably as effective as continuous catheter drainage for the treatment of pyogenic liver abscess, although further proof with a large-scale study is necessary. Due to the additional advantages of procedure simplicity, patient comfort, and reduced price, needle aspiration deserves to be considered as a first-line drainage approach. (Hepatology 2004;39:932-938.)
Coordinate expression of regulatory genes differentiates embryonic and perinatal forms of biliary atresia
Authors: Zhang Dong-Yi , Sabla Gregg , Shivakumar Pranavkumar , Tiao Greg , Sokol Ronald J. , Mack Cara , Shneider Benjamin L. , Aronow Bruce , Bezerra Jorge A.
Published: March 2004

The molecular basis for the embryonic and perinatal clinical forms of biliary atresia is largely undefined. In this study, we aimed to: 1) determine if the clinical forms can be differentiated at the transcriptional level, and 2) search for molecular mechanisms underlying phenotypic differences. To this end, we generated biotinylated cRNA probes from livers of age-matched infants with the embryonic (n = 5) and perinatal (n = 6) forms of biliary atresia at the time of diagnosis and hybridized them against the Affymetrix human HG-U133 A and B microarrays containing 44,760 gene products. Data filtering and two-way cluster analysis of the gene expression platform identified 230 genes with an expression profile that is highly distinctive of the clinical phenotypes. Functionally, the profile did not reveal a higher-order function for a specific cell type; instead, it uncovered a coordinated expression of regulatory genes. These regulatory genes were predominantly represented in the embryonic form (45% of genes), with a unique pattern of expression of genes involved in chromatin integrity/function (Smarca-1, Rybp, and Hdac3) and the uniform overexpression of five imprinted genes (Igf2, Peg3, Peg10, Meg3, and IPW), implying a failure to downregulate embryonic gene programs. In conclusion, embryonic and perinatal forms of biliary atresia are distinguished by gene expression profiling. The coordinate expression of regulators of chromatin structure/function and of imprinted genes provides evidence for a transcriptional basis for the pathogenesis of the embryonic form of biliary atresia. Further studies exploring these biological processes are required to determine the significance of these findings. Supplementary material for this article can be found at http://genet.cchmc.org. (Hepatology 2004;39:954-962.)
Electric foot shock stress-induced exacerbation of α-galactosylceramide-triggered apoptosis in mouse liver
Authors: Chida Yoichi , Sudo Nobuyuki , Sonoda Junko , Sogawa Hiroshi , Kubo Chiharu
Published: March 2004

Recently, liver natural killer T (NKT) cells, which are specifically stimulated by α-galactosylceramide (α-GalCer), were found to play a critical role in intrahepatic immunity to several infections and certain hepatic disorders. However, the role of psychophysical stress on NKT cell-dependent liver injury induced by α-GalCer still remains to be elucidated. In this study, we employed inescapable electric foot shock as the mode of psychophysical stress and evaluated its effect on α-GalCer-induced hepatitis. Pre-exposure of 12 hours of foot shock stress before α-GalCer administration significantly enhanced α-GalCer-triggered increase in serum alanine aminotransferase levels, followed by increases in both liver caspase-3 activity and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive hepatocytes, thus indicating that the liver NKT cell-dependent apoptotic response was exacerbated by stress. Foot shock stress also significantly increased both the number of liver NKT cells and Fas expression levels on hepatocytes. Pretreatment with RU-486, a glucocorticoid (GC) receptor antagonist, completely reversed such stress-induced enhancement of the α-GalCer-triggered serum alanine aminotransferase and hepatocyte Fas antigen responses. In contrast, such a reversal effect was not found in the mice pretreated with naloxone, a μ-opioid receptor antagonist, which thus suggests that an elevation of endogenous GCs, but not β-endorphin, as responsible for such stress-induced aggravation in mouse hepatitis models. In conclusion, foot shock stress-induced elevation of endogenous GCs exacerbates α-GalCer-initiated hepatic apoptosis through the expansion of liver NKT cells and the up-regulation of hepatocyte Fas antigen. (Hepatology 2004;39:1131-1140.)
Contingent labor as an enabler of entrepreneurial growth
Authors: Cardon Melissa S.
Published: March 2004

While all firms can benefit from engaging contingent labor, due to the flexibility, real options, and new knowledge these workers may provide, these benefits are compounded in emerging organizations due to their lack of resources, legitimacy, and time to focus on HR issues. By carefully weighing the risks and benefits, and making purposeful and intentional decisions concerning when and what types of contingent labor to utilize, as well as how to manage and integrate them with traditional employees, emerging ventures may experience enhanced growth and productivity. This may be particularly true during their start‐up, expansion, and diversification stages of development.©2004 Wiley Periodicals, Inc.
Trust and its alternatives
Authors: Alvarez Sharon A. , Barney Jay B. , Bosse Douglas A.
Published: March 2004

Most scholarly work on trust recognizes its importance as part of a nonmarket form of governance in exchanges
between firms. However, trust is only one such governance device that can be used; other devices such as
reputation, bargaining power, and contracts can also be used to govern exchanges. This article empirically
examines the relationships between trust, reputation, bargaining power, and contracts as governance devices in
agreements between smaller entrepreneurial firms and larger, more established firms. The findings suggest that
while the role of trust is an important one, it may be more effective when combined with other governance
devices. © 2004 Wiley Periodicals, Inc.
Microsatellite polymorphism of steroid hormone synthesis gene CYP11A1 is associated with advanced prostate cancer
Authors: Kumazawa Teruaki , Tsuchiya Norihiko , Wang Lizhong , Sato Kazunari , Kamoto Toshiyuki , Ogawa Osamu , Nakamura Akira , Kato Tetsuro , Habuchi Tomonori
Published: March 2004

It is widely recognized that androgen biosynthesis and metabolism are associated with the development and progression of prostate cancer. The human CYP11A1 gene (CYP11A1) encodes the P450scc enzyme, which mediates the first step in sex steroid hormone synthesis. The gene contains a (tttta)n‐5 bp tandem repeat microsatellite polymorphism located at 528 bp upstream of the translation initiation site and the CYP11A1 mRNA level may be modulated by the polymorphism. Recent studies suggested that the absence of the shortest (tttta)4 allele of the CYP11A1 polymorphism was associated with a risk of polycystic ovary syndrome and with a hyperandrogenic state in polycystic ovary syndrome patients. In our study which included 278 prostate cancer patients, 213 benign prostatic hyperplasia (BPH) patients and 299 male controls, we explored the association between the CYP11A1 polymorphism and prostate cancer on the hypothesis that the presence of the (tttta)4 allele may increase the risk of the development or progression of prostate cancer. In addition, we measured the serum levels of 6 steroid hormones or their metabolite (i.e., testosterone, free‐testosterone, estrone, estradiol, dehydroepiandrosterone and androstendione) in 156 control males subjects and compared those with and without the (tttta)4 allele. The polymorphism was evaluated by PCR amplification of a 145–170 bp fragment followed by polyacrylamid gel electrophoresis. The CYP11A1 allele consisted of 4, 6, 7, 8 and 9 (tttta)‐5 bp repeats. There was no significant difference in the genotype frequency as for the presence of the (tttta)4 allele between prostate cancer patients and male controls, and between prostate cancer patients and BPH patients. However, there was a significant difference in the genotype frequency in relation to the disease status. Prostate cancer patients without the (tttta)4 allele had an increased risk of metastatic disease (stage D) compared to those with the (tttta)4 allele [adjusted odds ratio (aOR)=1.76, 95% confidence interval (Cl)=1.07–2.90 and p =0.026]. Patients without the (tttta)4 allele had an increased risk of high grade prostate cancer (Gleason score 8 or more, or poorly differentiated cancer) compared to those with the (tttta)4 allele (aOR=1.79, 95% Cl=1.08–2.97 and p =0.025). No significant difference in the serum levels of 6 steroid hormones or their metabolites was found in the presence or absence of the (tttta)4 allele. Our results suggest that the CYP11A1 polymorphism may have a significant influence on the development of advanced and/or high grade prostate cancer and the absence of the CYP11A1 (tttta)4 allele, i.e., the homozygosity for the (tttta)6 or longer allele, could be a useful marker for the prediction of disease progression of prostate cancer. © 2004 Wiley‐Liss, Inc.
Digital photography: A primer for pathologists
Authors: Riley Roger S. , Ben‐Ezra Jonathan M. , Massey Davis , Slyter Rodney L. , Romagnoli Gina
Published: March 2004

The computer and the digital camera provide a unique means for improving hematology education, research, and patient service. High quality photographic images of gross specimens can be rapidly and conveniently acquired with a high‐resolution digital camera, and specialized digital cameras have been developed for photomicroscopy. Digital cameras utilize charge‐coupled devices (CCD) or Complementary Metal Oxide Semiconductor (CMOS) image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Since digital cameras do not utilize photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by email, or other applications. Several excellent digital still cameras are now available for less than $2,500 that capture high quality images comprised of more than 6 megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 11×14 inches. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images.

There are many applications of digital images of pathologic specimens. Since pathology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to developing large electronic hematology atlases, animated, audio‐enhanced learning experiences, multidisciplinary Internet conferences, and other innovative applications. Digital images of single microscopic fields (single frame images) are the most widely utilized in hematology education at this time, but single images of many adjacent microscopic fields can be stitched together to prepare “zoomable” panoramas that encompass a large part of a microscope slide and closely simulate observation through a real microscope. With further advances in computer speed and Internet streaming technology, the virtual microscope could easily replace the real microscope in pathology education. Later in this decade, interactive immersive computer experiences may completely revolutionize hematology education and make the conventional lecture and laboratory format obsolete. Patient care is enhanced by the transmission of digital images to other individuals for consultation and education, and by the inclusion of these images in patient care documents. In research laboratories, digital cameras are widely used to document experimental results and to obtain experimental data. J. Clin. Lab. Anal. 18:91–128, 2004. © 2004 Wiley‐Liss, Inc.
Evaluation of a novel kit (TF‐Test) for the diagnosis of intestinal parasitic infections
Authors: Gomes Jancarlo Ferreira , Hoshino‐Shimizu Sumie , S. Dias Luiz Cândido , Araujo Ana Júlia S.A. , Castilho Vera L.P. , Neves Fátima A.M.A.
Published: March 2004

Intestinal parasitic infections are currently a source of concern for Public Health agencies in developing and developed countries. Since three ovum‐and‐parasite stool examinations have been demonstrated to provide sensitive results, we designed a practical and economical kit (TF‐Test) that is now commercially available (Immunoassay Com. Ind. Ltda., São Paulo, Brazil). This kit allows the separate collection of three fecal specimens into a preservative solution. The specimens are then pooled, double‐filtered, and concentrated by a single rapid centrifugation process. The TF‐Test was evaluated in four different laboratories in a study using 1,102 outpatients and individuals living in an endemic area for enteroparasitosis. The overall sensitivity found using the TF‐Test (86.2–97.8%) was significantly higher (P<0.01) than the sensitivity of conventional techniques such as the Coprotest (NL Comércio Exterior Ltda, São Paulo, Brazil) and the combination of Lutz/Hoffman, Faust, and Rugai techniques (De Carli, Diagnóstico Laboratorial das Parasitoses Humanas. Métodos e Técnicas, 1994), which ranged from 48.3% to 75.9%. When the above combined three specimen technique was repeated with three specimens collected on different days, its sensitivity became similar (P>0.01) to that of the TF‐Test. The kappa index values of agreement for the TF‐Test were consistent (P<0.01), being higher and ranking in a better position than conventional techniques. The high sensitivity, cost/benefit ratio, and practical aspects demonstrate that the TF‐Test is suitable for individual diagnosis, epidemiological inquiries, or evaluation of chemotherapy in treated communities. J. Clin. Lab. Anal. 18:132–138, 2004. © 2004 Wiley‐Liss, Inc.
Reference distributions for alpha2‐macroglobulin: A practical, simple and clinically relevant approach in a large cohort
Authors: Ritchie Robert F. , Palomaki Glenn E. , Neveux Louis M. , Navolotskaia Olga , Ledue Thomas B. , Craig Wendy Y.
Published: March 2004

In this 11th article in a series, reference values of serum levels alpha2‐macroglobulin α2M) are examined. The study is based on a cohort of 40,420 Caucasian individuals from northern New England that were tested in our laboratory between 1994 and 2000. Measurements were standardized against Certified Reference Material (CRM 470)/Reference Preparation for Proteins in Human Serum (RPPHS) and the results analyzed using a previously described statistical approach. Individuals with unequivocal laboratory evidence of inflammation (C‐reactive protein >10 mg/L) were excluded in one leg of the study and included in the other, confirming that α2M does not respond to acute phase drive in man. Nephrotic syndrome, diabetes mellitus, and chronic liver disease have significant effect on levels of α2M. Dramatic changes occur during life with males higher from birth to age 12, females thereafter have higher values until the ninth decade. When values were expressed as multiples of the age‐ and gender‐specific median levels, the resulting distributions fitted a log‐Gaussian distribution well over a broad range. When patient data are normalized in this manner, the distribution parameters can be used to assign a centile corresponding to an individual's measurement thus simplifying interpretation. J. Clin. Lab. Anal. 18:139–147, 2004. © 2004 Wiley‐Liss, Inc.
Lamprey contractile protein genes mark different populations of skeletal muscles during development
Authors: Kusakabe Rie , Takechi Masaki , Tochinai Shin , Kuratani Shigeru
Published: March 2004

Agnathan lampreys retain ancestral characteristics of vertebrates in the morphology of skeletal muscles derived from two mesodermal regions: trunk myotomes and unsegmented head mesoderm. During lamprey development, some populations of myoblasts migrate via pathways that differ from those of gnathostomes. To investigate the evolution of skeletal muscle differentiation in vertebrates, we characterize multiple contractile protein genes expressed in the muscle cells of the Japanese lamprey, Lethenteron japonicum. Lamprey actin gene LjMA2, and myosin heavy chain (MyHC) genes LjMyHC1 and LjMyHC2 are all expressed in the developing skeletal muscle cells of early embryos. However, LjMyHC1 and LjMyHC2 are expressed only in cells originating from myotomes, while LjMA2 is expressed in both myotomal and head musculature. Thus, in lampreys, myotomes and head mesoderm differ in the use of genes encoding contractile protein isoforms. Phylogenetic tree analyses including lamprey MyHCs suggest that the variety of muscle MyHC isoforms in different skeletal muscles may correspond to the morphological complexity of skeletal muscles of different vertebrate species. Another lamprey actin gene LjMA1 is likely to be the first smooth muscle actin gene isolated from non‐tetrapods. We conclude that, in vertebrate evolution, the different regulatory systems for striated and smooth muscle‐specific genes may have been established before the agnathan/gnathostome divergence. J. Exp. Zool. (Mol. Dev. Evol.) 302B:121‐133, 2004. © 2004 Wiley‐Liss, Inc.
S100A1 gene transfer: a strategy to strengthen engineered cardiac grafts
Authors: Remppis Andrew , Pleger Sven T. , Most Patrick , Lindenkamp Jan , Ehlermann Philipp , Schweda Christopher , Löffler Eva , Weichenhan Dieter , Zimmermann Wolfram , Eschenhagen Thomas , Koch Walter J. , Katus Hugo A.
Published: March 2004

Background

Cardiac tissue replacement therapy, although a promising novel approach for the potential treatment of heart failure, still suffers from insufficient contractile support to the failing myocardium. Here, we explore a strategy to improve contractile properties of engineered heart tissue (EHT) by S100A1 gene transfer.

Methods

EHTs were generated from neonatal rat cardiomyocytes and transfected (MOI 10 PFU) with the S100A1 adenovirus (AdvS100A1, n = 25) while an adenovirus devoid of the S100A1 cDNA served as a control (AdvGFP, n = 30). Contractile properties of transfected EHTs were measured 7 days following gene transfer.

Results

Western blot analysis confirmed a 8.7 ± 3.6‐fold S100A1 protein overexpression in AdvS100A1‐transfected EHTs (n = 4; P < 0.01) that increased maximal isometric force (mN; AdvGFP 0.175 ± 0.03 vs. AdvS100A1 0.47 ± 0.06; P < 0.05) at 0.4 mmol/L extracellular calcium concentration [Ca2+]e. In addition, S100A1 overexpression enhanced both maximal Ca2+‐stimulated force generation (+81%; P < 0.05) and Ca2+‐sensitivity of EHTs (EC50% [Ca2+]e mM; AdvGFP 0.33 ± 0.04 vs. AdvS100A1 0.21 ± 0.0022; P < 0.05). The S100A1‐mediated gain in basal graft contractility was preserved throughout a series of isoproterenol interventions (10−9 to 10−6 M). Physiological properties of EHTs resembling intact heart preparations were preserved.

Conclusions

S100A1 gene transfer in EHT is feasible and augments contractile performance, while characteristic physiological features of EHT remain unchanged. Thus, specific genetic manipulation of tissue constructs prior to implantation should be part of an improved tissue replacement strategy in heart failure. Copyright © 2004 John Wiley & Sons, Ltd.
Transcriptional silencing is associated with extensive methylation of the CMV promoter following adenoviral gene delivery to muscle
Authors: Brooks Alan R. , Harkins Richard N. , Wang Peiyin , Qian Hu Sheng , Liu Pengxuan , Rubanyi Gabor M.
Published: March 2004

Background

Although the transient nature of transgene expression using first‐generation adenovirus (Ad) vectors is well known, the exact mechanisms responsible for this phenomenon are uncertain.

Methods

Rats were given intramuscular (i.m.) injections of a first‐generation Ad containing the human fibroblast growth factor 4 (hFGF‐4) gene driven by the cytomegalovirus (CMV) promoter and enhancer (CMV‐PE). The copy number of hFGF‐4 mRNA and viral DNA was measured in the same muscles by quantitative RT‐PCR and quantitative PCR at times between 1 h and 84 days after virus injection. Quantitative Southern blot analysis for the intact hFGF‐4 transcription unit DNA was also performed, and the methylation status of the CMV‐PE DNA in the muscle was determined using bisulfite sequencing.

Results

The copy number of hFGF‐4 mRNA peaked at 6 h then decreased 56‐fold by 24 h, and a further 240‐fold between days 3 and 28. Although the viral DNA copy number also decreased 23‐fold between 6 h and 28 days, the ratio of copies of hFGF‐4 mRNA per copy of viral DNA decreased 385‐fold over this period. Methylation of the CMV‐PE DNA in the muscle at both CpG and non‐CpG sites was observed 24 h after virus administration and had increased at day 7.

Conclusions

Decreased transcription associated with extensive methylation of the CMV‐PE was the major mechanism responsible for the decrease in transgene mRNA levels. Strategies for preventing transcriptional silencing will be valuable for improving the duration of transgene expression from adenoviral vectors. Copyright © 2004 John Wiley & Sons, Ltd.
CTb targeted non‐viral cDNA delivery enhances transgene expression in neurons
Authors: Barrett L. B. , Berry M. , Ying W.‐B. , Hodgkin M. N. , Seymour L. W. , Gonzalez A.‐M. , Read M. L. , Baird A. , Logan A.
Published: March 2004

Background

Efficient neuronal gene therapy is a goal for the long‐term repair and regeneration of the injured central nervous system (CNS). We investigated whether targeting cDNA to neurons with cholera toxin b chain conjugated non‐viral polyplexes led to increased efficiency of non‐viral gene transfer in the CNS. Here, we illustrate the potential for this strategy by demonstrating enhanced transfection of a differentiated neuronal cell type, PC12.

Methods

In vitro transfection efficiency of a cholera toxin b chain–poly(D‐lysine) molecular conjugate (CTb‐K100) was compared by fluorescence‐activated cell sorting (FACS) analysis of green fluorescent protein (GFP) expression and luminometric measurement of β‐galactosidase (β‐gal) expression, to untargeted poly(D‐lysine) (K100) in undifferentiated and NGF‐differentiated PC12 cells.

Results

Transfection of undifferentiated PC12 cells with CTb‐K100 polyplexes resulted in a 36‐fold increase in levels of pCMV‐DNALacZ expression and a 20‐fold increase in the frequency of transduction with pCMV‐DNAGFP, compared with untargeted K100 polyplexes. Treatment of PC12 cells with 50 ng/ml/day of NGF for 14 days led to differentiation to a neuronal phenotype. Transfection of NGF‐differentiated cells with CTb‐K100 polyplexes resulted in a 133‐fold increase in levels of pCMV‐DNALacZ expression and a 11‐fold increase in the percentage of cells transduced with pCMV‐DNAGFP, compared with untargeted K100 polyplexes. Transfection was dependent on CTb, with CTb‐K100‐mediated transfections competitively inhibited with free CTb in both PC12 phenotypes.

Conclusions

Non‐viral systems for gene transfer in damaged CNS show superior toxicological profiles to most viruses but are limited by inefficient and non‐selective gene expression in target tissue. Cholera toxin is known to interact preferentially with neuronal cells of the central and peripheral nervous systems, mediating binding through the b subunit, CTb, and the pentasaccharide moiety of the gangliosaccharide, GM1, which is present at high levels on the neuronal cell surface. Here, we show that a molecular conjugate of the CTb subunit, covalently linked to poly(D‐lysine), is able to successfully target and significantly enhance transfection of a neuronal cell type, NGF‐differentiated rat PC12 pheochromocytoma cells. This observation encourages the further development of non‐viral strategies for the delivery of therapeutic genes to neurons. Copyright © 2004 John Wiley & Sons, Ltd.
Efficient transduction and selection of human T‐lymphocytes with bicistronic Thy1/HSV1‐TK retroviral vector produced by a human packaging cell line
Authors: Lemoine François M. , Mesel‐Lemoine Mariana , Cherai Mustapha , Gallot Géraldine , Vié Henri , Leclercq Virginie , Trébèden‐Negre Hélène , Mammès Olivier , Boyer Olivier , Noguiez‐Hellin Patricia , Klatzmann David
Published: March 2004

Background

T‐cells expressing the HSV1‐TK suicide gene can be used for the control of graft‐versus‐host disease following allogeneic stem cell transplantation. To develop clinical trials based on such a strategy, we have generated under good manufacturing procedures a novel ‘split genome’ human packaging cell line (1704 cells).

Methods

To minimize the risk of generating replication‐competent retroviruses, pol was truncated to remove sequences overlapping with env. To improve retroviral infection and selection of transduced T‐cells, high titers of GALV‐pseudotyped retroviral particles harboring a bicistronic Thy1‐IRES‐TK vector coding for the CD90 GPI‐anchored membrane molecule were produced by 1704 cells.

Results

Using 1704 cell supernatant and an optimized transduction protocol, approximately 50% of primary T‐cells were transduced and could then be purified (∼95%) using clinical‐grade immunomagnetic beads directed against CD90. Over 96% of these OKT3/IL‐2‐activated CD90+‐selected T‐cells were killed by ganciclovir. Cell proliferation and cytokine production of transduced T‐cells and HLA‐restricted cytotoxicity of transduced T‐cell clones were identical to those of their non‐transduced counterparts cultured under the same conditions.

Conclusions

GALV‐pseudotyped retroviral particles harboring a bicistronic Thy1‐IRES‐TK vector allow efficient transduction and rapid selection of human T‐cells under conditions applicable for clinical trials using the new human 1704 packaging cell line. Copyright © 2004 John Wiley & Sons, Ltd.
1H‐MRSI of radiation effects in normal‐appearing white matter: Dose‐dependence and impact on automated spectral classification
Authors: Lee Michael C. , Pirzkall Andrea , McKnight Tracy R. , Nelson Sarah J.
Published: March 2004

Purpose

To identify radiation‐induced changes in healthy white‐matter spectra in the first six months following radiotherapy, and assess the impact of these changes on an automated algorithm for detecting spectral abnormalities.

Materials and Methods

1H‐MRSI was performed on 10 patients with grade IV gliomas who were to undergo radiation therapy. Choline (Cho), creatine (Cr), and N‐acetylaspartate (NAA) ratios were studied as a function of dose and time. The impact of these spectral changes on a spectral analysis algorithm was evaluated.

Results

The Cho/NAA ratios rose to values of 0.66 ± 0.15, 0.75 ± 0.21, and 0.73 ± 0.15 two months after therapy, compared to immediate post‐therapy values of 0.56 ± 0.15, 0.60 ± 0.16, and 0.61 ± 0.15 for the < 25, 25–50, and > 50 Gy dose groups, respectively. These maxima were followed by a dose‐dependent recovery. A similar trend was found in the Cho/Cr ratio. The automated spectral analysis system incorporated the changing Cho/NAA ratio into a global redefinition of healthy tissue, but did not account for dose‐dependent spatial variations in Cho/NAA ratios.

Conclusion

Radiation significantly alters the spectra of healthy tissues in the first six months after radiotherapy. This suggests that the radiation dose distribution should be considered during analysis of post‐therapy spectra. J. Magn. Reson. Imaging 2004;19:379–388. © 2004 Wiley‐Liss, Inc.
Comparison of TCA and ICA techniques in fMRI data processing
Authors: Zhao Xia , Glahn David , Tan Li Hai , Li Ning , Xiong Jinhu , Gao Jia‐Hong
Published: March 2004

Purpose

To make a quantitative comparison of temporal cluster analysis (TCA) and independent component analysis (ICA) techniques in detecting brain activation by using simulated data and in vivo event‐related functional MRI (fMRI) experiments.

Materials and Methods

A single‐slice MRI image was replicated 150 times to simulate an fMRI time series. An event‐related brain activation pattern with five different levels of intensity and Gaussian noise was superimposed on these images. Maximum contrast‐to‐noise ratio (CNR) of the signal change ranged from 1.0 to 2.0 by 0.25 increments. In vivo visual stimulation fMRI experiments were performed on a 1.9 T magnet. Six human volunteers participated in this study. All imaging data were analyzed using both TCA and ICA methods.

Results

Both simulated and in vivo data have shown that no statistically significant difference exists in the activation areas detected by both ICA and TCA techniques when CNR of fMRI signal is larger than 1.75.

Conclusion

TCA and ICA techniques are comparable in generating functional brain maps in event‐related fMRI experiments. Although ICA has richer features in exploring the spatial and temporal information of the functional images, the TCA method has advantages in its computational efficiency, repeatability, and readiness to average data from group subjects. J. Magn. Reson. Imaging 2004;19:397–402. © 2004 Wiley‐Liss, Inc.