bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression pattern of HSP25 in mouse preimplantation embryo: Heat shock responses during oocyte maturation
Authors: Kim Myungjin , Geum Dongho , Khang Inkoo , Park Young‐Mee , Kang Byung‐Moon , Lee Kyung‐Ah , Kim Kyungjin
Published: August 2002

Heat shock proteins (HSPs) are known to play an important role not only in various stress conditions such as exposure to heat shock, but also in normal development and/or differentiation. The role of small heat shock proteins such as HSP25 in early embryo development remains largely unknown. In the present study, we examined temporal and spatial expression patterns of HSP25 during mouse preimplantation embryo development. Reverse transcription‐polymerase chain reaction (RT‐PCR) showed that hsp25 mRNA was detected in unfertilized eggs. Hsp25 mRNA was induced by zygotic gene activation at 2‐cell stage, decreased slightly at 4‐cell, and re‐increased at morula, with the highest level at blastocyst stage. Interestingly, another form of hsp25 variant of which 156 bp (52 a.a.) was truncated within the exon1 region was observed in all stages of preimplantation embryos. We also investigated the sub‐cellular localization of HSP25 by fluorescence immunocytochemistry. HSP25 was detected in the cytoplasm under normal developmental condition. While acute heat shock (at 43°C for 30 min) caused no significant changes in the sub‐cellular localization of HSP25 in the developing mouse embryos, chronic heat shock (at 43°C for 3 hr) resulted in a denser immunostaining of HSP25 in the nucleus than in the cytoplasm, indicating a nuclear translocation of HSP25 by heat shock. As hsp25 mRNA was detected in the unfertilized egg as a maternal transcript, we examined the expression of hsp25 mRNA with RT‐PCR during oocyte maturation under normal and heat shock conditions. Hsp25 mRNA was detected at GV (germinal vesicle)‐, GVBD (germinal vesicle breakdown)‐, and MII (metaphase II)‐oocytes. The expression of hsp25 mRNA was increased markedly by both acute (for 30 min and 1 hr) and chronic (for 4 hr) heat shock, but returned to the basal level during recovery from heat shock in a time‐dependent manner, suggesting a thermo‐protective role of HSP25. In contrast to preimplantation embryos, HSP25 was detected both in the cytoplasm and the nucleus except for the nucleolus, and the cellular localization was not altered by heat shock. Finally, we investigated the effect of heat shock on oocyte maturation. When GV‐oocytes were exposed to acute heat shock (at 43°C for 15 min to 1 hr), they underwent the GVBD and the PB (polar body) emission successfully. However, under more stringent heat shock conditions (at 43°C for 2–4 hr), most oocytes were arrested at the GV‐stage, and the first PB was not developed, indicating that chronic heat shock might be inhibitory to the mouse oocyte maturation. Taken together, these findings suggest that HSP25 is important for mouse preimplantation embryo development and oocyte maturation. Mol. Reprod. Dev. 61: 3–13, 2002. © 2002 Wiley‐Liss, Inc.
Assessment of the neovascular permeability in glioma xenografts by dynamic T1 MRI with Gadomer‐17
Authors: Verhoye Marleen , van der Sanden Boudewijn P.J. , Rijken Paul F.J.W. , Peters Hans P.W. , Van der Kogel Albert J. , Pée Gilke , Vanhoutte Greetje , Heerschap Arend , Van der Linden Annemie
Published: August 2002

The uptake of Gadomer‐17, as probed by fast dynamic T1 measurements, was used to assess the vascular permeability surface‐area product per leakage volume of tissue (kTofts) of human glioma xenografts implanted in mice. With this approach we could discriminate between two types of glioma xenograft lines with a known difference in the perfused vascular architecture and degree of hypoxia. The T1 data were analyzed according to the Tofts‐Kermode compartment model. The fast‐growing E102 tumor demonstrated a homogeneous distribution of the vascular permeability surface area across the tumor (mean kTofts value = 0.18 ± 0.05 min−1). The slowly growing E106 tumor showed a more heterogeneous pattern. Three perfused tumor areas with differences in vascular permeability surface area could be distinguished: a well‐perfused periphery with high kTofts values (0.24 ± 0.04 min−1), perfused capillaries inside the tumor with low kTofts values (0.108 ± 0.026 min−1), and perfused capillaries adjacent to necrotic regions with high kTofts values (0.29 ± 0.10 min−1). On a different series of tumors, the hypoxic fractions were measured, and these were significantly higher in E106 tumors (0.14 ± 0.05) compared to tumors of the E102 line (0.03 ± 0.02). Magn Reson Med 47:305–313, 2002. © 2002 Wiley‐Liss, Inc.
Cerebral oxygen extraction fraction and cerebral venous blood volume measurements using MRI: Effects of magnetic field variation
Authors: An Hongyu , Lin Weili
Published: August 2002

The presence of magnetic background field inhomogeneity (ΔB) may confound quantitative measures of cerebral venous blood volume (vCBV) and cerebral oxygen extraction fraction (MR_OEF) with T‐based methods. The goal of this study was to correct its effect and obtain more accurate estimates of vCBV and MR_OEF. A 3D high‐resolution gradient echo sequence was employed to obtain ΔB maps by two algorithms. The ΔB maps were then used to recover the signal loss in images acquired by a 2D multiecho gradient echo / spin echo sequence. Finally, both quantitative estimates of MR_OEF and vCBV were obtained from the ΔB‐ corrected 2D multiecho gradient echo / spin echo images. A total of 12 normal subjects were studied. An overestimated vCBV was observed in the brain (4.29 ± 0.78%) prior to ΔB correction, while the measured vCBV was substantially reduced after ΔB correction. Whole brain vCBV of 2.97 ± 0.44% and 2.68 ± 0.47% were obtained by the two different ΔB correction methods, in excellent agreement with the reported results in the literature. Furthermore, when MR_OEF was compared with and without ΔB correction, no significant differences (P = 0.467) were observed. The ability to simultaneously obtain vCBV and MR_OEF noninvasively may have profound clinical implications for the studies of cerebrovascular disease. Magn Reson Med 47:958–966, 2002. © 2002 Wiley‐Liss, Inc.
T1 maps from shifted spin echoes and stimulated echoes
Authors: Ropele Stefan , Bammer Roland , Stollberger Rudolf , Fazekas Franz
Published: August 2002

A new pulse sequence for fast multislice T1 mapping is presented. This method is based on calculating T1 from spin echo (SE) and stimulated echo (STE) images obtained with different degrees of T1 weighting, and uses the interleaved acquisition scheme of the fast phase acquisition of composite echoes (FastPACE) technique. In contrast to the FastPACE technique, the two echoes are sampled separately. Experimental comparisons confirm that the new sequence layout overcomes most of the FastPACE restrictions, such as its motion sensitivity and the need for a fully complex data set. Moreover, this method offers a higher precision for long T1 values and a further reduction of acquisition time. Magn Reson Med 46:1242–1245, 2001. © 2001 Wiley‐Liss, Inc.
Monofocal motor neuropathy: Improvement with intravenous immunoglobulin
Authors: Felice Kevin J. , Goldstein Jonathan M.
Published: August 2002

Multifocal motor neuropathy (MMN) is a chronic, immune‐mediate, peripheral myelinopathy. Inherent in its name, MMN implies involvement of two or more motor nerves. We report three patients with weakness and partial motor conduction block restricted to a single nerve and localized to sites that are not at risk for entrapment or compression injury. None of the patients had sensory involvement and all showed a favorable response to intravenous immunoglobulin therapy. Based on these observations and reports of three additional patients, we believe that monofocal motor neuropathy is a partial form of MMN and should be treated as such. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Depletion and sizes of motor units in spinal muscular atrophy
Authors: Galea Victoria , Fehlings Darcy , Kirsch Susan , McComas Alan
Published: August 2002

Motor unit number estimation (MUNE) was applied to the biceps brachii muscles of 13 young patients (age 5–24 years) with spinal muscular atrophy (SMA) and the results compared with those of healthy control subjects matched for age and gender. In the SMA patients, all motor unit (MU) estimates fell below the control range, and there was good correspondence between the values for the two arms in the same subject. No correlation could be found between the MUNEs and the severity of the weakness. This unexpected result was attributed to the presence of small and normal‐sized MUs in the muscles of patients, in addition to MUs that appeared to be considerably enlarged. The threefold mean increase in MU potential size was insufficient to compensate for the MU loss. In addition, the study confirmed that there are, on average, approximately 130 MUs in the healthy biceps brachii muscle. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1166–1172, 2001
Survival of bundleless hair cells and subsequent bundle replacement in the bullfrog's saccule
Authors: Gale Jonathan E. , Meyers Jason R. , Periasamy Ammasi , Corwin T.
Published: August 2002

Our senses of hearing and balance depend upon hair cells, the sensory receptors of the inner ear. Millions of people suffer from hearing and balance deficits caused by damage to hair cells as a result of exposure to noise, aminoglycoside antibiotics, and antitumor drugs. In some species such damage can be reversed through the production of new cells. This proliferative response is limited in mammals but it has been hypothesized that damaged hair cells might survive and undergo intracellular repair. We examined the fate of bullfrog saccular hair cells after exposure to a low dose of the aminoglycoside antibiotic gentamicin to determine whether hair cells could survive such treatment and subsequently be repaired. In organ cultures of the bullfrog saccule a combination of time‐lapse video microscopy, two‐photon microscopy, electron microscopy, and immunocytochemistry showed that hair cells can lose their hair bundle and survive as bundleless cells for at least 1 week. Time‐lapse and electron microscopy revealed stages in the separation of the bundle from the cell body. Scanning electron microscopy (SEM) of cultures fixed 2, 4, and 7 days after antibiotic treatment showed that numerous new hair bundles were produced between 4 and 7 days of culture. Further examination revealed hair cells with small repaired hair bundles alongside damaged remnants of larger surviving bundles. The results indicate that sensory hair cells can undergo intracellular self‐repair in the absence of mitosis, offering new possibilities for functional hair cell recovery and an explanation for non‐proliferative recovery. © 2002 Wiley Periodicals, Inc. J Neurobiol 50: 81–92, 2002; DOI 10.1002/neu.10002
Durable and refreshable polymeric N‐halamine biocides containing 3‐(4′‐vinylbenzyl)‐5,5‐dimethylhydantoin
Authors: Sun Yuyu , Sun Gang
Published: August 2002

A novel vinyl‐hydantoin monomer, 3‐(4′‐vinylbenzyl)‐5,5‐dimethylhydantoin, was synthesized in a good yield and was fully characterized with Fourier transform infrared (FTIR) and 1H NMR spectra. Its homopolymer and copolymers with several common acrylic and vinyl monomers, such as vinyl acetate, acrylonitrile, and methyl methacrylate, were readily prepared under mild conditions. The polymers were characterized with FTIR and 1H NMR, and their thermal properties were analyzed with differential scanning calorimetry studies. The halogenated products of the corresponding copolymers exhibited potent antibacterial properties against Escherichia coli, and the antibacterial properties were durable and regenerable. The structure–property relationships of the polymers were further discussed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3348–3355, 2001
Enlarging the library of poly‐(L‐lysine citramide) polyelectrolytic drug carriers
Authors: Couffin‐Hoarau Anne‐Claude , Boustta Mahfoud , Vert Michel
Published: August 2002

Poly‐(L‐lysine citramide) is a degradable drug carrier of the polyelectrolyte type that is composed of citric acid and L‐lysine building blocks. In a previous work, poly‐(L‐lysine citramide) was synthesized by the interfacial polycondensation of α‐hydroxy acid protected citryl dichloride with COOH‐protected lysine diamine. Because of head‐to‐head and head‐to‐tail and tail‐to‐tail linkages in the chains as well as various side reactions such as deprotection of the α‐hydroxy acid moieties and intramolecular imide ring formation, a very large family of degradable polyelectrolyte copolymers was obtained. All the members of this family hydrolytically degrade to the same end products. In this study, another route was explored based on the polycondensation of α‐hydroxy acid protected citric acid pentafluorophenyl diesters, namely, citrobenzal dipentafluorophenyl and citrochloral dipentafluorophenyl with N‐N′‐trimethylsilylated COOH‐protected L‐lysine. The resulting polymers were characterized by IR, NMR, and size exclusion chromatographic analyses. The resulting chain structures and repeat units were identified from these characterizations and are discussed as compared with characteristics exhibited by analogous polymers resulting from interfacial polycondensation. Differences observed at the intermediate stage involving protected polymers were largely erased during the final deprotection stage because of imide formation during final hydrolysis under the selected conditions. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3475–3484, 2001
Awareness and barriers to use of cancer support and information resources by HMO patients with breast, prostate, or colon cancer: patient and provider perspectives
Authors: Eakin Elizabeth G. , Strycker Lisa A.
Published: August 2002

This study assessed patient awareness and use—as well as obstacles to use—of HMO‐ and community‐based psychosocial support services designed for cancer patients. Participants were a randomly selected group of patients from a large Northwest HMO, with breast (N=145), prostate (N=151), or colon cancer (N=72), and their oncology and urology providers (N=29). Patient awareness was highest for HMO‐based services (68–90%) and lower for community‐ (33%) or Internet‐based (10–14%) services, and use rates were low across all services (range 2–8%). Providers reported referring 70% of their patients to HMO cancer support services, but their estimates of actual patient use of these services (40%) were inflated. Providers reported few barriers to referring patients to support services. The most commonly reported patient barriers to using such services were already having adequate support, lack of awareness of the service, and lack of provider referral. Results of regression analyses suggest that education, physician referral, social support, and spirituality may be important influences on use of cancer support services. This study takes a first step toward understanding patient use of existing cancer support services and suggests ways to increase participation in these services. Copyright © 2001 John Wiley & Sons, Ltd.
Exercise adherence in breast cancer survivors training for a dragon boat race competition: a preliminary investigation
Authors: Courneya Kerry S. , Blanchard Chris M. , Laing Dot M.
Published: August 2002

Recent research has applied the theory of planned behavior (TPB) to understanding exercise after a cancer diagnosis, but studies are few and have been limited by retrospective designs, self‐report measures of exercise and varied results. In the present study, we extended this research by using a prospective design and an objective measure of exercise adherence. Participants were a convenience sample of 24 breast cancer survivors attending a twice weekly, 12‐week training program in preparation for a dragon boat race competition. Participants completed a baseline questionnaire that assessed demographic and medical variables, past exercise, and the TPB (i.e. beliefs, subjective norm, attitude, perceived behavioral control and intention). Program attendance was monitored over a 12‐week period by the class instructor. Overall, participants attended 66% of the training sessions. Multiple regression analyses indicated that: (a) intention was the sole determinant of program attendance and explained 35% of the variance; (b) the TPB constructs explained 49% of the variance in intention with subjective norm being the most important determinant; and (c) the key underlying beliefs were support from physician, spouse, and friends, and confidence in being able to attend the training class when having limited time, no one to exercise with, fatigue, and other health problems. Based on this preliminary study, it was concluded that the TPB may provide a good framework on which to base interventions designed to promote exercise in breast cancer survivors. Copyright © 2001 John Wiley & Sons, Ltd.
Nasal airflow and resistance measured by active anterior rhinomanometry in healthy children and adolescents
Authors: Zapletal A. , Chalupová J.
Published: August 2002

Rhinomanometry allows objective assessment of nasal patency in pediatric patients with nasal and other respiratory problems. However, no reliable reference values are available in the pediatric age group. We measured nasal inspiratory airflow and nasal inspiratory resistance of the right and left nostrils (V′nar, V′nal, Rnar, and Rnal) and total nasal inspiratory flow and resistance (V′na and Rna) at a transnasal pressure of 150 Pa during quiet breathing in healthy children with a closed mouth by using active anterior rhinomanometry. Cross‐sectional measurements were done in 192 healthy Caucasian children and adolescents free of nasal or other respiratory diseases (age, 2–19 years; body height, 94–190 cm; 95 boys and 97 girls).

The values of V′na, V′nar, and V′nal increased significantly with an increase of body height or age (P < 0.0001) . Rna, Rnar, and Rnal significantly decreased with an increase of body height and age (P < 0.0001). No significant statistical differences were found between boys and girls (P = 0.11) or between right and left nostrils (P = 0.07). V′nar and Rnar comprised 50.1%, and V′nal and Rnal 49.9%, of total V′na and Rna, respectively. Best‐fit regression equations relating rhinomanometric parameters and body height or age were power functions.

We obtained reference regression equations with upper and lower limits, and prepared tables listing reference (normal) values of rhinomanometric parameters in healthy pediatric Caucasian patients, against which patients with nasal obstruction can be compared. Pediatr Pulmonol. 2002; 33:174–180. © 2002 Wiley‐Liss, Inc.
Genotypic characterization of Pseudomonas aeruginosa strains recovered from patients with cystic fibrosis after initial and subsequent colonization
Authors: Munck Anne , Bonacorsi Stéphane , Mariani‐Kurkdjian Patricia , Lebourgeois Muriel , Gérardin Michèle , Brahimi Naïma , Navarro Jean , Bingen Edouard
Published: August 2002

Chronic infection by Pseudomonas aeruginosa (PA) in patients with cystic fibrosis (CF) is preceded by a period of colonization and acute infection. Early aggressive antibiotic treatment of initial colonisation may prevent or at least delay chronic pulmonary infection. We initiated treatment with a combination of IV β‐lactam tobramycin, followed by nebulized colistin when PA was first isolated from patients with CF. Subsequent serial PA isolates obtained from these colonized CF patients were characterized by means of molecular methods to determine whether they were genetically related to the initial strain.

Initial colonization was eradicated in all 19 patients. All patients reacquired PA within 3–25 months during the 3 years of follow‐up. Fourteen patients acquired a new PA strain with a distinct genotypic profile, suggesting a new source of contamination. Five patients had two PA isolates with identical genotypes, suggesting either previous undetected respiratory tract colonization or a persistent environmental source of contamination. Pediatr Pulmonol. 2001; 32:288–292. © 2001 Wiley‐Liss, Inc.
Relationships between sulfonylurea herbicide treatment of host plants and the performance of herbivorous insects
Authors: Kjær Christian , Heimbach Udo
Published: August 2002

Previous work had shown that the sulfonylurea herbicide chlorsulfuron affected the survival of a herbivorous insect species dwelling on a sub‐lethally exposed host plant. Further experiments have been conducted to establish whether this negative effect was a single occurrence characteristic for the specific insect–plant interaction and the specific herbicide tested. Three insect–plant interactions were tested for the effects of selected sulfonylurea herbicides, ie metsulfuron‐methyl, chlorsulfuron and tribenuron‐methyl. The species pairs tested were Pieris brassicae/Brassica napus, Gastrophysa polygoni/Fallopia convolvulus and Sitobium avenae/Triticum aestivium. No significant effects on survival and relative growth rate of P brassicae or G polygoni were found when treating the host plants with sulfonylurea herbicides. However, the host plants had a significantly reduced root and shoot growth rate when treated with herbicide. Treating T aestivium with the recommended field rate of metsulfuron‐methyl did not cause any change in development time, growth rate or fecundity of S avenae feeding on the host plants. The data presented suggest that the increased mortality observed for G polygoni larvae feeding on chlorsulfuron‐treated host plants observed earlier was characteristic for this herbicide and for the specific plant–insect interaction only.

© 2001 Society of Chemical Industry
EHF theory of chemical reactions V. Nature of manganese–oxygen bonds by hybrid density functional theory (DFT) and coupled‐cluster (CC) methods
Authors: Isobe H. , Soda T. , Kitagawa Y. , Takano Y. , Kawakami T. , Yoshioka Y. , Yamaguchi K.
Published: August 2002

Hybrid density functional theory (DFT) and post‐Hartree–Fock methods are compared by depicting potential energy curves of the O–O dissociation of hydroperoxide and the M–O dissociation of transition‐metal oxides. The former approach includes BLYP, B2LYP, B3LYP, and more general hybrid DFT methods, while the unrestricted Hartree–Fock (UHF) coulpled‐cluster (UCC) SD(T) method is considered as the latter approach. The hybrid DFT methods can reproduce the potential curve of the O–O dissociation process and the dissociation energy of HOOH by UCCSD(T). The methods are also useful for depicting potential curves of copper oxide (CuO) and manganese oxide (MnO), and reproduce the experimental M–O binding energies. The nature of Mn–O bonds in the naked Mn–O, Mn–O porphyrine system and model complexes, XH3Mn(IV)O2Mn(IV)H3Y (X,Y=O,H), are examined in relation to the possible mechanisms of oxygenation reactions. It is found that the radical character of Mn–O bonds increases with the increase of the oxidation number of the Mn ion in these systems. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Investigation of atrazine metabolism in river sediment by high‐performance liquid chromatography/mass spectrometry
Authors: Takáts Zoltán , Vargha Márta , Vékey Károly
Published: August 2002

Microbial degradation processes play an important role in chemical water clearance taking place in river sediments. Bacteria remove not only easily degradable organic species, but various xenobiotics as well, producing clear and xenobiotic free water for bank‐filtered wells. Atrazine is a widely used herbicide, and it is one of the most common xenobiotics present in Danube water. In this study the pathway and kinetics of atrazine metabolism of sedimental microbiota were studied. Samples were collected from river sediment and from pure microbial growth cultures. An analytical scheme including sample preparation, chromatography and mass spectrometry was developed and optimised. Solid‐phase extraction (SPE) was found to be satisfactory for sample preparation. For qualitative analysis of samples both reversed‐phase and normal‐phase high‐performance liquid chromatography/mass spectrometry (HPLC/MS) methods were developed and used. Selectivity, detection limits and accuracy of the two methods were compared. Using this analytical scheme, the full atrazine metabolism of the organism Comamonas acidovorans was explored. Altogether, 12 metabolites were identified from the original compound to the urea end product. Detection limits in the range of 50 ng L−1−1µg L−1 were obtained for different metabolites. Copyright © 2001 John Wiley & Sons, Ltd.
TTV, a new human virus with single stranded circular DNA genome
Authors: Hino Shigeo
Published: August 2002

TT virus (TTV) was found in 1997 from a hepatitis patient without virus markers. However, the real impact of TTV on liver diseases remains uncertain to date. Due to the lack of suitable cell systems to support the growth of TTV, the biology of TTV is still obscure. This review tries to summarise the current status of TTV on aspects other than the taxonomic diversity of TTV. TTV was the first human virus with a single stranded circular DNA genome. TTV was considered to be a member of Circoviridae, but others suggested it conformed to a new family. TTV is distinct from ambisense viruses in the genus Circovirus, since the former genome is negative stranded. The genome structure of TTV is more related to chicken anaemia virus in the genus Gyrovirus, however, the sequence similarity is minimal except for a short stretch at 3816–3851 of TA278. Currently the working group is proposing the full name for TTV as TorqueTenoVirus and the TTV‐like mini virus as TorqueTenoMiniVirus (TTMV) in a new genus Anellovirus (ring). TTVs are prevalent in non‐human primates and human TTV can cross‐infect chimpanzees. Furthermore, TTV sequences have been detected in chickens, pigs, cows and sheep. TTV can be transmitted by mother‐to‐child infection. However, within a year after birth, the prevalence reaches the same level for children born to both TTV‐positive and TTV‐negative mothers even without breast‐feeding. The non‐coding region surrounding a short 113 nt GC‐rich stretch and occupying approximately one‐third of the genome is considered to contain the putative replication origin. Three mRNAs are expressed by TTV, 3.0 and 1.2 and 1.0 kb species. A protein translated from the 3.0 kb mRNA is considered to be the major capsid protein as well as replicase. The nature of the proteins translated by the other two mRNAs are still putative. Copyright © 2002 John Wiley & Sons, Ltd.
Correction of the P‐value after multiple coding of an explanatory variable in logistic regression
Authors: Liquet Benoit , Commenges Daniel
Published: August 2002

We propose a method and a program to determine a significance level for a series of codings of an explanatory variable in logistic regression. Dichotomous and Box–Cox transformations are considered. Three methods of correcting the significance level are studied: the Bonferroni method; Efron's method, which uses the correlation between successive tests, and the exact calculation by numerical integration using all correlations. A simulation study has led to a strategy for the choice and number of the different codings of the variable. This method is illustrated using the data of a study of the relation between cholesterol and dementia. Copyright © 2001 John Wiley & Sons, Ltd.
The strategic value of CEO external directorate networks: implications for CEO compensation
Authors: Geletkanycz Marta A. , Boyd Brian K. , Finkelstein Sydney
Published: August 2002

This study examines the relationship between CEO external directorate networks and CEO compensation. Drawing on previous research showing a link between executives' external networks, firm strategy, and performance, the study argues that executive external networks are strategically valuable to firms; thus, they should be reflected in executive compensation. The study further examines whether firm diversification, with its elevated demand for strategic resources, moderates the relationship between CEO external directorate networks and pay. Hypotheses are tested using a sample of 460 Fortune 1000 firms. Analyses reveal that the rewards to CEO external directorate networks are contingent upon the firm's level of diversification. Implications for future research and practice are discussed. Copyright © 2001 John Wiley & Sons, Ltd.
α2A‐Adrenergic receptors are present in μ‐opioid receptor containing neurons in rat medial nucleus tractus solitarius
Authors: Glass Michael J. , Pickel Virginia M.
Published: August 2002

Agonists of the alpha‐2A‐adrenergic‐ (α2A‐AR) and the μ‐opioid‐receptor (μOR) jointly affect autonomic functions that are also disregulated in animals undergoing withdrawal from chronic administration of the μOR agonist morphine. Cardiovascular and gastrointestinal reflexes are mediated, in part, by the medial nucleus of the solitary tract (mNTS) at caudal (cNTS) and intermediate (iNTS) subregions. Together, this evidence suggests that α2A‐AR and μOR may be colocalized within many of the same neuronal profiles in both the intermediate and caudal mNTS. In order to examine whether α2A‐AR and μOR are present within common somata, dendrites, or axon terminals in the mNTS, we used electron microscopic immunocytochemistry for the detection of antisera against each receptor at intermediate and caudal levels of this brain region. Most of the dually labeled profiles were somata and dendrites. Of all dual‐labeled profiles in the iNTS 49% were somata and were 47% dendrites, whereas in the cNTS 61% were somata and 32% were dendrites. Within dual‐labeled profiles, the intracellular distribution of α2A‐AR and μOR differed. μOR was more frequently associated with the plasmalemma, whereas α2A‐AR was often affiliated with vesicular organelles. Few axon terminals, and even fewer glia, contained both markers. We also frequently observed single‐labeled α2A‐AR glia that apposed exclusively μOR‐containing dendrites or axon terminals. These findings indicate that somata and dendrites contain functional sites for convergent μOR and α2A‐AR activation. In addition, each receptor is positioned for involvement in intercellular signaling between apposed neurons and glia. Activation of α2A‐AR on μOR‐containing somata or dendrites, or on glia apposed to μOR‐containing neurons, may help to account for the efficacy of α2A‐AR agonists in relieving some of the autonomic symptoms of opiate withdrawal. Synapse 43:208–218, 2002. © 2002 Wiley‐Liss, Inc.
Differential regulation of GAD67, enkephalin and dynorphin mRNAs by chronic‐intermittent L‐dopa and A2A receptor blockade plus L‐Dopa in dopamine‐denervated rats
Authors: Carta Anna R. , Pinna Annalisa , Cauli Omar , Morelli Micaela
Published: August 2002

Adenosine A2A receptor antagonists have been proposed as an effective therapy in the treatment of Parkinson's disease. In the present study, we compared the modifications on striatal glutamate decarboxylase (GAD67), enkephalin, and dynorphin mRNA levels produced by a chronic‐intermittent administration of L‐3,4‐dihydroxyphenyl‐alanine (L‐dopa) (6 mg/kg) with those produced by the adenosine A2A receptor antagonist SCH 58261 (5 mg/kg) plus L‐dopa (3 mg/kg) in unilaterally 6‐hydroxydopamine (6‐OHDA)‐lesioned rats. As previously reported, L‐dopa (6 mg/kg) and SCH 58261 (5 mg/kg) plus L‐dopa (3 mg/kg) produced the same degree of turning behavior after the first administration. However, while L‐dopa (6 mg/kg) induced a sensitized turning behavior response during the course of the treatment, which indicated a dyskinetic potential, SCH 58261 (5 mg/kg) plus L‐dopa (3 mg/kg) produced a stable turning behavior response, which was predictive of absence of dyskinetic side effects. Unilateral 6‐OHDA lesion produced an elevation in striatal GAD67 and enkephalin mRNA levels and to a decrease in dynorphin mRNA levels. Chronic‐intermittent L‐dopa (6 mg/kg) treatment increased the striatal levels of GAD67, dynorphin, and enkephalin mRNA in the lesioned side as compared to the vehicle treatment. Chronic‐intermittent SCH 58261 (5 mg/kg) plus L‐dopa (3 mg/kg) as well as L‐dopa (3 mg/kg) or SCH 58261 (5 mg/kg) alone did not produce any significant modification in GAD67, dynorphin, or enkephalin mRNA levels in the lesioned striatum as compared to the striatum of vehicle‐treated rats. The results show that combined SCH 58261 plus L‐dopa did not produce long‐term changes in markers of striatal efferent neurons activity and suggest that the lack of modifications in GAD67 and dynorphin mRNA after SCH 58261 plus L‐dopa might correlate with the lack of turning behavior sensitization which predicts drug dyskinetic potential. Synapse 44:166–174, 2002. © 2002 Wiley‐Liss, Inc.
Conditioned‐fear stress increases Fos expression in monoaminergic and GABAergic neurons of the locus coeruleus and dorsal raphe nuclei
Authors: Ishida Yasushi , Hashiguchi Hiroyuki , Takeda Ryuichiro , Ishizuka Yuta , Mitsuyama Yoshio , Kannan Hiroshi , Nishimori Toshikazu , Nakahara Daiichiro
Published: August 2002

Many studies have demonstrated that physical or psychological stress can increase Fos expression in brainstem monoaminergic nuclei. Little is known, however, about the extent to which stress increases the expression of Fos in monoaminergic and nonmonoaminergic neurons in the brainstem. We examined the effects of conditioned‐fear (CF) stress following mild footshock (FS) as unconditioned stress on Fos expression in the monoaminergic and GABAergic neurons of the ventral tegmental area (VTA), locus coeruleus (LC), and dorsal raphe nucleus (DR) in rats. The CF stress significantly increased the number of Fos‐positive (Fos+) cells in both the LC and DR, whereas it did not increase the number in the VTA. Using a double‐labeling technique, we combined Fos immunostaining with that for tyrosine hydroxylase (TH), serotonin (5‐HT), or GABA for histochemical identification of the CF stress‐induced Fos+ neurons. The percentage of TH/Fos double‐labeled cells resulting from CF stress was 63% of the Fos+ cells in the LC, whereas 52% of the Fos+ cells contained 5‐HT in the DR. We also found that approximately 60% of the CF stress‐induced Fos+ cells were GABAergic neurons in these brain regions. These results indicate that CF stress induces intense Fos expression in the noradrenergic LC and serotonergic DR neurons, but not in the dopaminergic VTA neurons. They also indicate that not only monoaminergic neurons but also GABAergic neurons within the LC and DR are activated by the stress. Synapse 45:46–51, 2002. © 2002 Wiley‐Liss, Inc.
On the evaluation of systemic science education reform: Searching for instructional sensitivity
Authors: Ruiz‐Primo Maria Araceli , Shavelson Richard J. , Hamilton Laura , Klein Steve
Published: August 2002

We propose a multilevel‐multifaceted approach to evaluating the impact of education reform on student achievement that would be sensitive to context and small treatment effects. The approach uses different assessments based on their proximity to the enacted curriculum. Immediate assessments are artifacts (students' products) from the enactment of the curriculum; close assessments parallel the content and activities of the unit/curriculum; proximal assessments tap knowledge and skills relevant to the curriculum, but topics can be different; and distal assessments reflect state/national standards in a particular knowledge domain. To provide evidence about the sensitivity of the multilevel approach in ascertaining outcomes of hands‐on science programs we administered close, proximal, and distal performance assessments to evaluate the impact of instruction based on two Full Option Science System units—Variables, and Mixtures and Solutions—in a Bay Area school district. Results indicated that close assessments were more sensitive to the changes in students' pre‐ to post‐test performance than proximal assessments. © 2002 Wiley Periodicals, Inc. J Res Sci Teach 39: 369–393, 2002
Offshore fatigue design turbulence
Authors: Larsen Gunner C.
Published: August 2002

Fatigue damage on wind turbines is mainly caused by stochastic loading originating from turbulence. While onshore sites display large differences in terrain topology, and thereby also in turbulence conditions, offshore sites are far more homogeneous, as the majority of them are likely to be associated with shallow water areas. However, despite this fact, specific recommendations on offshore turbulence intensities, applicable for fatigue design purposes, are lacking in the present IEC code. This article presents specific guidelines for such loading. These guidelines are based on the statistical analysis of a large number of wind data originating from two Danish shallow water offshore sites. The turbulence standard deviation depends on the mean wind speed, upstream conditions, measuring height and thermal convection. Defining a population of turbulence standard deviations, at a given measuring position, uniquely by the mean wind speed, variations in upstream conditions and atmospheric stability will appear as variability of the turbulence standard deviation. Distributions of such turbulence standard deviations, conditioned on the mean wind speed, are quantified by fitting the measured data to logarithmic Gaussian distributions. By combining a simple heuristic load model with the parametrized conditional probability density functions of the turbulence standard deviations, an empirical offshore design turbulence intensity is determined. For pure stochastic loading (as associated with standstill situations), the design turbulence intensity yields a fatigue damage equal to the average fatigue damage caused by the distributed turbulence intensity. If the stochastic loading is combined with a periodic deterministic loading (as in the normal operating situation), the proposed design turbulence intensity is shown to be conservative. Copyright © 2001 John Wiley & Sons, Ltd.
Intact carcasses as enrichment for large felids: Effects on on‐ and off‐exhibit behaviors
Authors: Mcphee M. Elsbeth
Published: August 2002

Reducing stereotypic behaviors in captive animals is a goal for zoological institutions worldwide, and environmental enrichment is one tool commonly used to meet that end. Behavioral needs associated with feeding, however, are often neglected in large carnivores. To address these needs, I tested the effects of calf carcasses as enrichment for large felids. Over 14 weeks, I provided nine animals with up to seven intact carcasses. The cats were housed at Toledo Zoo, Potawatomi Zoo, and Binder Park Zoo. Animals were observed off and on exhibit for changes in feeding, natural, stereotypic, active, and inactive behaviors. I compared treatment behaviors with behaviors observed during a baseline period in which the animals were fed traditional processed diets. For these nine cats, carcass provision decreased off‐exhibit stereotypic behaviors but had little impact on on‐exhibit behaviors. Zoo Biol 21:37–47, 2002. © 2002 Wiley‐Liss, Inc.
Bone bruise in the acutely injured knee
Authors: Bretlau Thomas , Tuxøe Jon , Larsen Lone , Jørgensen Uffe , Thomsen Henrik S. , Lausten Gunnar
Published: August 2002

We used MRI to study the lesions in a consecutive group of 64 patients with an acute trauma of the knee and normal plain radiography during the winter season. Bone bruise was present in 35 of the patients, and these were referred to subsequent MRI 4 and 12 months later. After 4 months bone bruise was still present in 69% of the patients and after 12 months in 12%. Soft tissue lesions, for example, lesion in the meniscus, ACL rupture, or MCL lesion was present in 94% of the patients with bone bruise. Interobserver agreement varied from good to excellent. Soft tissue lesions are found in almost all patients with bone bruise, and these generally resolve 4–12 months after the injury. In the patients with no bone bruise the number of ligament injuries was lower.
Surgical Treatment for Lung Hydatid Disease
Authors: Safioleas Michael , Misiakos Evangelos P. , Dosios Theodosios , Manti Christine , Lambrou Panagiota , Skalkeas Gregory
Published: August 2002

Lung is the second most common site for hydatid disease after the liver. The aim of this study is to present the clinical symptomatology, diagnostic evaluation, and surgical techniques for the treatment of lung hydatid disease. During the last 25 years, 42 patients with lung hydatid cysts were treated surgically in our department. In four patients there were cysts in the liver and in one case in the spleen. The cysts were located in the right lung in 16 patients (38%), in the left lung in 23 patients (54.8%), and in both lungs in 3 patients (7.14%). Eighteen patients (42.9%) presented with complications: suppuration in one patient (2.4%), rupture to the bronchial tree in 16 patients (38%), and pneumothorax in one patient (2.4%). Diagnosis was established preoperatively in all cases; chest radiography and computed tomography were most helpful for diagnosis. Forty‐six operations were performed in 42 patients; three patients with bilateral cysts underwent staged thoracotomies, and one patient was reoperated for recurrent disease. All cases were managed surgically, with several types of radical (34 cases) or conservative (12 cases) procedures. Radical procedures were lobectomy and rarely pneumonectomy, which were used more often during the first half of the study period. Cystectomy with capitonnage, the most commonly performed conservative procedure, was mainly used during the second half of the study period. Postoperative morbidity was 15.2% and the 30‐day mortality rate was 0%. In one case there was postoperative hemorrhage that required reexploration. The median hospital stay for uncomplicated cases was 12 days and for complicated cases 21 days. In conclusion, pulmonary hydatidosis often presents with complications requiring emergency surgery. A lung‐conserving operation is the treatment of choice for lung hydatid disease and offers a good surgical outcome with a minimal recurrence rate.
Outcome after Surgery for Primary Hyperparathyroidism: Ten‐year Prospective Follow‐up Study
Authors: Walgenbach Siegfried , Hommel Gerhard , Junginger Theo
Published: August 2002

Clinical outcome after surgery for primary hyperparathyroidism was evaluated in a prospective long‐term, follow‐up study. From August 1, 1987 to August 31, 1998 a total of 360 patients were prospectively investigated and included in a follow‐up study. All patients underwent follow‐up examinations at regular surveillance intervals. The postoperative course is known for 94.5% of all patients. Follow‐up was 1 month to 10 years (median 24 months; mean 34.5 ± 29.8 months). Asymptomatic primary hyperparathyroidism was rare (6%), and its true frequency could be confirmed only postoperatively because some of the patients were unaware of mild symptoms of hypercalcemic syndrome prior to surgery. Surgical cure was obtained in 97.7% of patients after initial cervical exploration; and successful parathyroidectomy provided long‐term relief of symptoms. Within 2 years postoperatively, 84% of the patients recovered fully from hypercalcemic syndrome; in 58% of these patients recovery occurred within the first month after surgery. Skeletal symptoms persisted in 24% of patients 2 years postoperatively. To date no patient has developed recurrence of primary hyperparathyroidism. During follow‐up in our study population mortality was significantly higher than the expected mortality risk for the German population as a whole (p= 0.00024). The present prospective follow‐up study yielded conclusive outcome research data after operative therapy for primary hyperparathyroidism. The high cure rate and low morbidity, as well as the increased mortality, in our study population during follow‐up after successful operative therapy for the disease emphasize the importance of early diagnosis and early surgical treatment for primary hyperparathyroidism, even in the absence of manifest symptoms.
Hypomagnesemia and Hypocalcemia after Thyroidectomy: Prospective Study
Authors: Wilson Robert B. , Erskine Catherine , Crowe Philip J.
Published: August 2002

Hypomagnesemia after total thyroidectomy has not been studied extensively. Our anecdotal experience suggests that it may be important in some patients after thyroid excision. The hypomagnesemic hypocalcemic syndrome has been described in other disease states in which a state of functional hypoparathyroidism exists. This study was designed to determine the incidence of hypomagnesemia after total thyroidectomy and relate it to hypocalcemia and symptoms during the postoperative period. A prospective study of all patients undergoing total thyroidectomy between September 1994 and July 1996 was performed. Patient data, thyroid function, retrosternal extension, initial versus reoperative surgery, operative details, parathyroid resection, and pathology were recorded. Calcium, magnesium, electrolytes, blood count, liver function tests, and albumin were measured prior to surgery and twice daily during the postoperative period. Fifty patients underwent total thyroidectomy: 68% were hypocalcemic, 72% were hypomagnesemic, and 36% were symptomatic during the postoperative period. Hypomagnesemia and gender were associated with hypocalcemia. Volume of fluid and neck dissection were associated with low magnesium levels. Hypomagnesemia and parathyroid resection were risk factors for symptoms after thyroidectomy. No patients developed permanent hypoparathyroidism. Transient hypocalcemia and hypomagnesemia occur frequently after total thyroidectomy. The etiology of this phenomenon is probably multifactorial. Patients are more likely to be symptomatic when both cations are low, and attempting to correct only hypocalcemia may prolong symptoms. It is important to monitor both calcium and magnesium levels after total thyroidectomy and to correct deficiencies to facilitate prompt resolution of symptoms.
Pain and Leukemia: The Stories of Three Children
Authors: Bossert Elizabeth A. , Van Cleve Lois , Adlard Kathleen , Savedra Marilyn
Published: August 2002

The stories of the pain experience of three children with acute leukemia during the first year after diagnosis are presented in this report. To provide a broad picture, children who represent various characteristics were selected: ages 6, 9, and 15 years; two male and one female; two Latino and one Caucasian; two English- speaking and one Spanish; two with acute lymphocytic leukemia and one with acute myelocytic leukemia. Consideration of the disease, procedures, treatment, and normal childhood pain experiences will provide the nurse who cares for these children guidance in knowing why and when pain may occur, which will lead to timely interventions for the pain.