bluuebunny/crossref_metadata_2025 huggingface dataset:
Density functional theory studies on the dissociation energies of metallic salts: relationship between lattice and dissociation energies
Authors: Kim Chang Kon , Won Jongok , Kim Hoon Sik , Kang Yong Soo , Li Hong Guang , Kim Chan Kyung
Published: August 2002

The formation and physicochemical properties of polymer electrolytes strongly depend on the lattice energy of metal salts. An indirect but efficient way to estimate the lattice energy through the relationship between the heterolytic bond dissociation and lattice energies is proposed in this work. The heterolytic bond dissociation energies for alkali metal compounds were calculated theoretically using the Density Functional Theory (DFT) of B3LYP level with 6‐311+G(d,p) and 6‐311+G(2df,p) basis sets. For transition metal compounds, the same method was employed except for using the effective core potential (ECP) of LANL2DZ and SDD on transition metals for 6‐311+G(d,p) and 6‐311+G(2df,p) calculations, respectively. The dissociation energies calculated by 6‐311+G(2df,p) basis set combined with SDD basis set were better correlated with the experimental values with average error of ca. ±1.0% than those by 6‐311+G* combined with the LANL2DZ basis set. The relationship between dissociation and lattice energies was found to be fairly linear (r>0.98). Thus, this method can be used to estimate the lattice energy of an unknown ionic compound with reasonably high accuracy. We also found that the dissociation energies of transition metal salts were relatively larger than those of alkaline metal salts for comparable ionic radii. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 827–834, 2001
Molecular dynamics simulation of the hydrocarbon region of a biomembrane using a reduced representation model
Authors: Whitehead Lewis , Edge Colin M. , Essex Jonathan W.
Published: August 2002

The development of a coarse‐grained reduced‐representation model of the hydrocarbon region of a biological membrane is reported. The potential is based on the popular Gay–Berne model of liquid crystals, and involves the linking of individual Gay–Berne ellipsoids by harmonic springs to form each hydrocarbon chain. Diffusion coefficients and order parameters have been calculated by molecular dynamics computer simulations for a range of parameter sets. The results clearly demonstrate the presence of a phase transition from an ordered low‐temperature solid phase reminiscent of the Lβ′ phase of phospholipids, to a high‐temperature disordered phase reminiscent of the Lα phase. Order parameters calculated for each layer of the model are consistent with the experimental segmental order parameters reported for dipalmitoyl phosphatidylcholine. The application of this model to the study of small molecule diffusion within the membrane core is proposed. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1622–1633, 2001
Polymer collapse, protein folding, and the percolation threshold
Authors: Meirovitch Hagai
Published: August 2002

We study the transition of polymers in the dilute regime from a swollen shape at high temperatures to their low‐temperature structures. The polymers are modeled by a single self‐avoiding walk (SAW) on a lattice for whichlof the monomers (the H monomers) are self‐attracting, i.e., if two nonbonded H monomers become nearest neighbors on the lattice they gain energy of interaction (ϵ=−∣ϵ∣); the second type of monomers, denoted P, are neutral. This HP model was suggested by Lau and Dill (Macromolecules 1989, 22, 3986–3997) to study protein folding, where H and P are the hydrophobic and polar amino acid residues, respectively. The model is simulated on the square and simple cubic (SC) lattices using the scanning method. We show that the ground state and the sharpness of the transition depend on the lattice, the fractiongof the H monomers, as well as on their arrangement along the chain. In particular, if the H monomers are distributed at random andgis larger than the site percolation threshold of the lattice, a collapsed transition is very likely to occur. This conclusion, drawn for the lattice models, is also applicable to proteins where aneffectivelattice with coordination number between that of the SC lattice and the body centered cubic lattice is defined. Thus, the average fraction of hydrophobic amino acid residues in globular proteins is found to be close to the percolation threshold of the effective lattice. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 166–171, 2002
Dynamics of a protein and water molecules surrounding the protein: Hydrogen‐bonding between vibrating water molecules and a fluctuating protein
Authors: Yoshioki Shuzo
Published: August 2002

Internal and rigid‐body motions of bovine pancreatic trypsin inhibitor (BPTI) and of water molecules surrounding the BPTI are studied in a vicinity of an energy minimum using a normal mode analysis proposed as the independent molecule model. Water's rigid‐body motion is predominant in comparison to its internal motions. We have derived information about the relationship between the magnitude of a thermal ellipsoid of an H‐bonding atom and the anisotropy of its ellipsoid, and the relationship between the magnitude of the ellipsoid and the H‐bond strength. We see a relationship between vibrational frequencies (assuming rigid‐body motion of the water molecules) and the H‐bond strength of the water taking part in this H‐bonding. Analyzing the H‐bond strength, we found that a hydrogen in water is likely to H‐bond to oxygen in the protein, whereas an oxygen in water has a less strong preference to H‐bond to the protein. For water molecules acting as the hydrogen acceptor, strong H‐bonding has longer lifetimes than weak H‐bonding. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 402–413, 2002
Direct constructions of additive codes
Authors: Bierbrauer Jürgen
Published: August 2002

A code isqm‐aryq‐linear if its alphabet forms anm‐dimensional vector space over 𝔽qand the code is linear over 𝔽q. Theseadditive codesform a natural generalization of linear codes. Our main results are direct constructions of certain families of additive codes. These comprise the additive generalization of the Kasami codes, an additive generalization of the Bose‐Bush construction of orthogonal arrays of strength 2 as well as a class of additive codes which are being used for deep space communication. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 207–216, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.20000
The search for the holy grail: Heart rate variability and Thought Field Therapy
Authors: Herbert James D. , Gaudiano Brandon A.
Published: August 2002

Thought Field Therapy (TFT) is one of several unusual psychotherapies that have witnessed rapid growth over the past few years, despite the absence of scientific support. Promoters of TFT frequently cite changes in heart rate variability (HRV) as evidence of TFT's effects. Pignotti and Steinberg (2001) present reports of 39 cases in which HRV was assessed prior to and immediately following TFT. Serious methodological shortcomings preclude interpretation of these data with respect to either the efficacy of TFT or the clinical utility of HRV. Ethical concerns are raised about the aggressive promotion of TFT and the misuse of HRV. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 1207–1214, 2001.
Depression in chronic medical illness: The case of coronary heart disease
Authors: Burg Matthew M. , Abrams David
Published: August 2002

Depression is an important predictor of morbidity and mortality in patients with coronary disease, particularly after myocardial infarction, independent of previous cardiac history or CAD severity. Depression also is associated with poor long‐term psychosocial outcomes. The prevalence of major depression among post‐MI patients is 15 to 20%, with an additional 27% reporting symptoms of minor depression. This article briefly reviews the literature on depression in patients with coronary disease, including previously published efforts to treat the disorder in this group. A case review then is provided, highlighting important aspects of treatment. © 2001 John Wiley & Sons, Inc. J Clin Psychol/In Session 57: 1323–1337, 2001.
Patterns of object relations and reality testing deficits in schizophrenia: Clusters and their symptom and personality correlates
Authors: Bell Morris D. , Greig Tamasine Conway , Bryson Gary , Kaplan Edward
Published: August 2002

Bell Object Relations Reality Testing Inventory (BORRTI) profile scores were used to cluster 222 outpatients with schizophrenia or schizoaffective disorder. An eight‐cluster solution was subjected to replication analysis, and six clusters were found valid and replicable. These clusters were sorted into three pairs that were interpreted as follows: Residually Impaired consisted of Sealed‐Over Recovery and Integrated Recovery; Socially Withdrawn consisted of Socially Withdrawn and Socially Withdrawn—Autistic; and Psychotically Egocentric consisted of Psychotically Egocentric and Psychotically Egocentric—Severe. Clusters were compared on Positive and Negative Syndrome Scale ratings and on subscales from the Eysenck Personality Questionnaire. MANOVAs indicated significant differences among clusters. These differences provided further interpretations of cluster membership. Implications for the use of BORRTI profiles for treatment and rehabilitation planning are discussed. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 1353–1367, 2001.
Regulation of expression and activity of four PKC isozymes in confluent and mechanically stimulated UMR‐108 osteoblastic cells
Authors: Geng W.D. , Boskovic G. , Fultz M.E. , Li C. , Niles R.M. , Ohno S. , Wright G.L.
Published: August 2002

The transcript (mRNA), protein levels, enzyme activity, and cellular localization of four protein kinase C (PKC) isozymes identified in rat osteogenic sarcoma cells (UMR‐108) were studied at confluent density and during mechanical stress (cyclic stretch). Western blot analysis indicated that growth to confluent density significantly increased the protein levels of cPKC‐α (11.6‐fold), nPKC‐δ (5.3‐fold), and nPKC‐ϵ (22.0‐fold) but not aPKC‐ζ. Northern blot analysis indicated a significant (2.3‐fold) increase in the 10 kb transcript of cPKC‐α, a slight (1.3‐fold) increase in that of nPKC‐ϵ but no detectable change in that of the remaining isozymes. Enzyme activity assays of the individually immunoprecipitated isozymes yielded detectable kinase activity only for PKC‐α, PKC‐δ, and PKC‐ϵ and only in confluent cells, corroborating the selective increase of these isozymes at confluent density. The UMR‐108 cells showed a dramatic orientation response to mechanical stress with cell reshaping and alignment of the cell long axis perpendicular to the axis of force, remodeling of the actin cytoskeleton, and the appearance of multiple peripheral sites which stained for actin, vinculin, and PKC in separate experiments. Longer term mechanical stress beyond 24 h, however, resulted in no significant change in the mRNA level, protein level, or enzyme activity of any of the four PKC isozymes investigated. The results indicate that there are isozyme‐selective increases in the protein levels of PKC isozymes of osteoblastic UMR‐108 cells upon growth to confluence which may be regulated at the transcriptional or the post‐transcriptional level. The results from UMR‐108 cells support the earlier proposal (Carvalho RS, Scott JE, Suga DM, Yen EH. 1994. J Bone Miner Res 9(7):999–1011) that PKC could be involved in the early phase of mechanotransduction in osteoblasts through the activation of focal adhesion assembly/disassembly and the remodeling of the actin cytoskeleton. © 2001 Wiley‐Liss, Inc.
Regulation of BMP‐7 expression by retinoic acid and prostaglandin E2
Authors: Paralkar V.M. , Grasser W.A. , Mansolf A.L. , Baumann A.P. , Owen T.A. , Smock S.L. , Martinovic S. , Borovecki F. , Vukicevic S. , Ke H.Z. , Thompson D.D.
Published: August 2002

Bone morphogenetic proteins (BMPs) are members of the transforming growth factor‐beta (TGF‐β) gene superfamily of growth and differentiation factors. Members of the BMP family were originally cloned and characterized by their ability to induce ectopic bone formation. Of the various BMPs cloned, the bone inductive ability of BMP‐7 (OP‐1) and BMP‐2 has been well characterized. Both BMP‐7 and ‐2 have been shown to have clinical utility in the healing of non‐union fractures. However, in spite of the various advances in BMP research, the physiological regulation of BMPs is not well understood. Here we studied the expression of BMP‐7 by cloning a 4.6‐kB fragment of the human BMP‐7 promoter (hBMP‐7p) and placing it upstream of a luciferase reporter. The promoter reporter construct was stably transfected into different cell backgrounds and its regulation by various factors was investigated. We show that retinoic acid (RA) treatment results in an upregulation of the hBMP‐7p reporter activity. This regulation of the hBMP‐7p was further confirmed by Northern blot, PCR, and Western blot analyses, which showed an increase in both BMP‐7 mRNA and protein expression upon treatment with RA. We further show that RA specifically upregulates expression of osteocalcin via activation of BMP‐7 mRNA and protein in vitro. Similarly, prostaglandin E2 (PGE2) treatment increases BMP‐7 mRNA and protein levels, but does not transcriptionally activate the hBMP‐7p. Additionally, in vivo expression of BMP‐7 in bone was increased upon PGE2 treatment. In conclusion, RA and PGE2 upregulate BMP‐7 protein expression both in vitro and in vivo. J. Cell. Physiol. 190: 207–217, 2002. © 2002 Wiley‐Liss, Inc.
Expression and targeting of the tight junction protein CLDN1 in CLDN1‐negative human breast tumor cells
Authors: Hoevel Thorsten , Macek Robert , Mundigl Olaf , Swisshelm Karen , Kubbies Manfred
Published: August 2002

Claudins and occludin constitute the major transmembrane proteins of tight junctions (TJs). We have previously identified the human homologue of the murine Cldn1, CLDN1 (SEMP1) that is expressed in normal, mammary gland‐derived epithelial cells but is absent in most human breast cancer cell lines. To investigate the potential functions of CLDN1 protein in tumor and normal epithelial cells, we developed an I‐NGFR retroviral vector and monoclonal anti‐CLDN1 antibody. In subconfluent and confluent breast cancer cells, MDA‐MB‐435 and MDA‐MB‐361, endogenous CLDN1 expression was not detected by an anti‐CLDN1 monoclonal antibody by Western blot analysis or quantitative RT‐PCR. When CLDN1‐negative breast cancer cell lines were transduced with a CLDN1 retrovirus the cells express CLDN1 mRNA constitutively as shown by quantitative RT‐PCR. Immunofluorescence analyses of the CLDN1 retroviral transduced breast tumor cells using monoclonal antibodies against CLDN1 reveals a subcellular distribution at cell–cell contact sites similar to the CLDN1 homing pattern in T47‐D cells, which express endogenous CLDN1. This cell–cell contact co‐localization of CLDN1 was evident in CLDN1‐transduced breast tumor cells which fail to express occludin protein (MDA‐MB‐361 and MDA‐MB‐435) and express relatively little ZO‐1 protein (MDA‐MB‐435), suggesting that other proteins may be responsible for targeting of CLDN1 to cell–cell contact sites. The re‐expression of CLDN1 decreases the paracellular flux of 3 and 40 kDa dextran despite the absence of occludin in the MDA‐MB‐361 tumor cells. Our findings indicate that in CLDN1‐negative breast tumor cells, the basal protein partner requirements for physiological homing of the CLDN1 protein are intact, and that CLDN1 gene transfer and protein expression itself might be sufficient to exert a TJ‐mediate gate function in metastatic tumor cells even in the absence of other TJ‐associated proteins, such as occludin. J. Cell. Physiol. 191: 60–68, 2002. © 2002 Wiley‐Liss, Inc.
Havep53gene mutations and protein expression a different biological significance in colorectal cancer?*
Authors: Bazan Viviana , Migliavacca Manuela , Tubiolo Carla , Macaluso Marcella , Zanna Ines , Corsale Simona , Amato Antonella , Calò Valentina , Dardanoni Gabriella , Morello Vincenza , Farina Mario La , Albanese Ida , Tomasino Rosa Maria , Gebbia Nicola , Russo Antonio
Published: August 2002

p53 alterations are considered the most common genetic events in many types of neoplasms, including colorectal carcinoma (CRC). These alterations include mutations of the gene and/or overexpression of the protein. The aim of our study was to assess whether in 160 patients undergoing resective surgery for primary operable CRC there was an association between p53 mutations and protein overexpression and between these and other biological variables, such as cell DNA content (DNA‐ploidy) and S‐phase fraction (SPF), and the traditional clinicopathological variables. p53 mutations, identified by PCR‐SSCP‐sequencing analysis, were found in 68/160 patients (43%) and positive staining for p53 protein, detected with the monoclonal antibody DO‐7, was present in 48% (77/160) of the cases, with agreement of 57% (91/160). In particular, a significant association was found between increased p53 expression and genetic alterations localized in the conserved regions of the gene or in the L3 DNA‐binding domain and the specific type of mutation. Furthermore, both overexpression of p53 and mutations in the conserved areas of the gene were found more frequently in distal than in proximal CRCs, suggesting that they might be “biologically different diseases.” Although p53 mutations in conserved areas were associated with flow cytometric variables, overexpression of p53 and mutations in its L3 domain were only related respectively to DNA‐aneuploidy and high SPF. These data may reflect the complex involvement of p53 in the different pathways regulating cell‐cycle progression. In conclusion, the combination of the mutational status and immunohistochemistry of p53, and flow cytometric data may provide an important insight into the biological features of CRCs. J. Cell. Physiol. 191: 237–246, 2002. © 2002 Wiley‐Liss, Inc.
Versatile protein tag, SUMO: Its enzymology and biological function
Authors: Kim Keun IL , Baek Sung Hee , Chung Chin Ha
Published: August 2002

Small ubiquitin‐related modifier (SUMO) is a member of a ubiquitin‐like protein family that regulates cellular function of a variety of target proteins. SUMO and ubiquitin are synthesized as precursors that need to be processed prior to conjugation to target proteins, and their mature forms have a similar tertiary structure. The mechanism for SUMO conjugation is also analogous to that of the ubiquitin system, such as the utilization of E1, E2, and E3 cascade enzymes. However, the biological consequence of SUMO modification is quite different from that of the ubiquitin system. Whereas ubiquitination of most proteins is for the degradative pathway, SUMO modification of target proteins is involved in nuclear protein targeting, formation of subnuclear structures, regulation of transcriptional activities or DNA binding abilities of transcription factors, and control of protein stability. This review will summarize the recent progress made in the enzymology of SUMO and its biological significance. © 2002 Wiley‐Liss, Inc.
Growth and characterization of a cell line from a human primary neuroendocrine carcinoma of the skin (Merkel cell carcinoma) in culture and as xenograft
Authors: Krasagakis Konstantin , Almond‐Roesler Brigitte , Geilen Christoph , Fimmel Sabine , Krengel Sven , Chatzaki Ekaterini , Gravanis Achille , Orfanos Constantin E.
Published: August 2002

The primary neuroendocrine carcinoma of the skin or Merkel cell carcinoma (MCC) is a skin tumor with aggressive biological behaviour. Experimental models for investigating the biological properties of the tumor are prerequisite for developing new therapeutic approaches. In this study, we report the establishment and characterisation of a cell line derived from the lymph‐node metastasis of a patient with highly aggressive MCC. Merkel carcinoma cells (MCC‐1) grew as floating aggregates in suspension cultures for more than two years and over 70 subcultures. The proliferation rate in suspension cultures was rather moderate with a population doubling time of 69 h. The immunocytochemical pattern of the cultured MCC‐1 was similar to that of the original tumor with expression of cytokeratin 18, neuron‐specific enolase, neurofilaments, and synaptophysin. In addition, reverse transcriptase polymerase chain reaction (RT‐PCR) revealed presence of chromogranin A mRNA in the MCC‐1 cell line. Furthermore, electron microscopy yielded the rare finding of neuroendocrine granules in the cytoplasm of the cultured cells. The cell line MCC‐1 was able to form colonies in soft agar. Nude mice developed solid tumors with similar histology to the original tumor after subcutaneous and intravenous injections of cultured MCC‐1, and malignant ascites was seen after intraperitoneal injection. Also, two MCC‐1 sublines were established by reculturing cells from the xenografts grown in vivo and immunocytochemistry confirmed their neuroendocrine origin. The MCC‐1 line may thus serve as a model for studying the biology and the metastatic potential of Merkel cell carcinoma. © 2001 Wiley‐Liss, Inc.
Bioaccumulation of palladium by Desulfovibrio desulfuricans
Authors: Yong Ping , Rowson Neil A , Farr J Peter G , Harris I Rex , Macaskie Lynne E
Published: August 2002

Palladium uptake by resting cell suspensions of Desulfovibrio desulfuricans NCIMB 8307 was studied without or with electron donor (formate), which gave metal uptake attributable to biosorption of Pd(II) and bioreduction of Pd(II) to Pd(0), respectively. The maximum biosorption capacity of palladium (at pH 2) was up to 196 mg Pd g−1 dry cells (1.85 mmol g−1; approx 20% of the dry weight). Biosorption was to 85% of the maximum in less than 10 min and the biomass was saturated within 30 min. Biosorption of Pd(II) was greater from the chloro‐ than the ammine complex and was inhibited in the presence of excess chloride ion. Bioreductive accumulation of Pd(II) from Pd(NH3)42+ was achieved in the presence of electron donor (formate) but was also inhibited by excess Cl−. Up to 100% of Pd(II) reduction to Pd(0) was achieved within 5 min anaerobically at pH 7 and 30 min at pH 3. Pd(0) was localized on the biomass surface using electron microscopy and was characterized using energy dispersive X‐ray microanalysis (EDAX) and X‐ray diffraction analysis (XRD). Biosorption was Pd‐specific with respect to Pt and Rh using test solutions and acid (aqua regia) leachates from spent automotive catalysts. The total Pd removed from the latter was only 15%, attributable to the inhibitory effect of residual chloride ion from the acidic extractant. Pd biorecovery is limited by the need for an improved extraction technology to minimize the formation of PdCl42− in solution rather than by constraints of the Pd‐accumulating biomass.

© 2002 Society of Chemical Industry
A developmental approach to understanding Fragile X syndrome in females
Authors: Keysor Cynthia S. , Mazzocco Michèle M.M.
Published: August 2002

The psychological phenotype of females with fragile X syndrome (FraX) is discussed, focusing primarily on empirical findings over the past decade and on studies of probands with the full mutation (FM). A developmental approach is used to help characterize specific patterns of cognitive, neuropsychological, social, emotional, and behavioral functioning across the lifespan of females with FraX. Approximately half of females with the syndrome present with cognitive abilities that fall in the borderline to mentally retarded range, and the remaining females with average intellectual functioning may experience relative deficits in math achievement and problems with attention and executive functioning. Reports of socio‐emotional functioning are somewhat inconsistent, due in part, perhaps, to methodological differences in study design. To date, much of what we understand about the psychological phenotype of FraX is based on cross‐sectional studies of girls and women with the disorder. Symptoms associated with shyness, and social anxiety and avoidance have been reported in some school‐age, adolescent, and adult females with FraX. Only recently have efforts begun to identify the developmental trajectory of FraX in infants and toddlers. There is a void of information specific to these developmental periods. Identifying key deficits in cognitive and socio‐emotional functioning has important implications for early detection and intervention for girls with FraX. Directions for future research are discussed. Microsc. Res. Tech. 57:179–186, 2002. © 2002 Wiley‐Liss, Inc.
Membrane traffic in myelinating oligodendrocytes
Authors: Krämer Eva‐Maria , Schardt Anke , Nave Klaus‐Armin
Published: August 2002

In the central nervous system (CNS), the myelin sheath is synthesised by oligodendrocytes as a specialised subdomain of an extended plasma membrane, reminiscent of the segregated membrane domains of polarised cells. Myelination takes place within a relatively short period of time and oligodendrocytes must have adapted membrane sorting and transport mechanisms to achieve such a high rate of myelin synthesis and to maintain the unique organisation of the myelin membrane. In adult life, maintenance of the functional myelin sheath requires a carefully orchestrated balance of myelin synthesis and turnover. Imbalance in these processes may cause dys‐ or demyelination and disease. This review summarises what is currently known about myelin protein trafficking and mistrafficking in oligodendrocytes. We also present data demonstrating distinct transport pathways for myelin structural proteins and the expression of SNARE proteins in differentiating oligodendrocytes. Myelinating glial cells may well serve as a model system for studying general aspects of membrane trafficking and organisation of membrane domains. Microsc. Res. Tech. 52:656–671, 2001. © 2001 Wiley‐Liss, Inc.
Expression of Leu‐19 (CD56, N‐CAM) and nitric oxide synthase (NOS) I in denervated and reinnervated human skeletal muscle
Authors: Gosztonyi Georg , Naschold Ulrich , Grozdanovic Zarko , Stoltenburg‐Didinger Gisela , Gossrau Reinhart
Published: August 2002

Neural cell adhesion molecule (N‐CAM, Leu‐19, CD 56) expression appears during muscle fiber regeneration and after denervation. Sarcolemma‐associated nitric oxide synthase (NOS) I, however, disappears from denervated myofibers. The dynamics of expression of both proteins were studied in 5 cases of acute/subacute denervation, 28 cases of chronic denervation with and without collateral reinnervation, 5 cases of the intermediate type spinal muscular atrophy (SMA 2), and in 2 normal biopsies. NOS I and its NADPH diaphorase (NADPHd) activity disappeared from the sarcolemma region shortly after denervation, and before the appearance of denervation atrophy. N‐CAM was found diffusely distributed in the sarcoplasm at the most severe phase of denervation atrophy in the majority of highly atrophic fibers. During reinnervation, NOS I expression remained absent and in part of the cases the target/targetoid phenomenon appeared. In parallel with the increase in volume of the reinnervated muscle fibers, the intensity of N‐CAM immunoreactivity decreased progressively. After full restitution of muscle fiber caliber, the target/targetoid phenomenon and N‐CAM immunostaining disappeared completely, and, finally, NOS I reappeared in the sarcolemma region. The sarcolemmal expression of dystrophin and dystrophin‐associated proteins was unchanged during denervation. NOS I was completely absent in children with SMA 2, since the protein does not appear before 5 years of age in skeletal muscle, while N‐CAM was very intensely expressed in the sarcoplasm of highly atrophic denervated muscle fibers. In conclusion, this study suggests that innervation is an important factor for selective gene expression and positioning of NOS I and N‐CAM in skeletal muscle and gives practical information for the assessment of the phase and developmental stage of the denervation and reinnervation process. Microsc. Res. Tech. 55:187–197, 2001. © 2001 Wiley‐Liss, Inc.
Sex from W to Z: Evolution of vertebrate sex chromosomes and sex determining genes
Authors: Marshall Graves Jennifer A. , Shetty Swathi
Published: August 2002

Sex determination in major vertebrate groups appears to be very variable, including systems of male heterogamety, female heterogamety and a variety of genetic and environmental sex determining systems. Yet comparative studies of sex chromosomes and sex determining genes now suggest that these differences are more apparent than real. The sex chromosomes of even widely divergent groups now appear to have changed very little over the last 300+ million years, and even independently derived sex chromosomes seem to have followed the same set of evolutionary rules. The sex determining pathway seems to be extremely conserved, although the control of the genes in this pathway is vested in different elements. We present a scenario for the independent evolution of XY male heterogamety in mammals and ZW female heterogamety in birds and some reptiles. We suggest that sex determining genes can be made redundant, and replaced by control at another step of a conserved sex determining pathway, and how choice of a gene as a sex switch has led to the evolution of new sex chromosome systems. J. Exp. Zool. 290:449–462, 2001. © 2001 Wiley‐Liss, Inc.
South African regional industrial policy: from border industries to spatial development initiatives
Authors: Hartzenberg Trudi
Published: August 2002

Regional industrial development has been the focus of a number of very specific policy initiatives in South African since the 1960s. Until the end of the 1980s these initiatives were driven by political imperative: to develop the homeland areas and to stem migration to South Africa's cities. They failed on both counts. In the early 1990s, industrial policy was markedly less focused on location. However more recently the Spatial Development Initiatives (SDI) and Industrial Development Zone (IDZ) programmes have both involved the identification of industrial locations and used incentives to encourage firms to locate in these areas. The SDI programme has specifically taken South African regional industrial policy into the southern African region with its cross‐border development corridors.

The paper questions the underlying rationale for South Africa's regional industrial policy, and in particular the role of incentives in influencing firm‐level decisions, including their location decisions. The tentative conclusion is that there is no reason to suppose that the South African government could or can do better than the market in directing firm‐level location decisions, and that industrial policy incentives may be far less important to the firm than macroeconomic and market conditions. Copyright © 2001 John Wiley & Sons, Ltd.
Variation in eggshell characteristics and in intrauterine egg retention between two oviparous clades of the lizard lacerta vivipara: insight into the oviparity–viviparity continuum in squamates
Authors: Heulin Benoit , Ghielmi Samuele , Vogrin Nusa , Surget‐Groba Yann , Guillaume Claude Pierre
Published: August 2002

The concept of the oviparity–viviparity continuum refers to the wide range in the length of intrauterine egg retention and, hence, in the stage of embryonic development at oviposition existing in squamates. The evolutionary process underlying this continuum may involve not only a lengthening of egg retention in utero, but also a marked reduction in the thickness of the eggshell. The idea that there may exist a negative correlation between the developmental stage reached by the embryo at oviposition and the eggshell thickness within squamates, although supported by the comparison of oviparous vs. viviparous species, has seldom been evaluated by comparing eggshell thickness of oviparous forms with different lengths of intrauterine egg retention. Eggs of two distinct oviparous clades of the lizard Lacerta vivipara were compared. The eggs laid by females from Slovenian and Italian populations have thicker eggshells, contain embryos on average less developed at the time of oviposition, and require a longer incubation period before hatching than the eggs laid by females from French oviparous populations. Our data and several other examples available from the literature support the idea that the lengthening of intrauterine retention of eggs and the shortening of the subsequent external incubation of eggs are associated with reduction in the thickness of the eggshell, at least in some lineages of oviparous squamates. The current hypotheses that may account for this correlation are presented and a few restrictions and refinements to those hypotheses are discussed. In particular, other changes, such as increased vascularization of the oviduct and of the extraembryonic membranes, may play the same role as the decrease of eggshell thickness in facilitating prolonged intrauterine egg retention in squamates. Future studies should also consider the hypothesis that the length of intrauterine retention might directly depend on the extent of maternal–fetal chemical communication through the eggshell barrier. J. Morphol. 252:255–262, 2002. © 2002 Wiley‐Liss, Inc.
Vascularization of the brains of the Atlantic and Pacific hagfishes, Myxine glutinosa and Eptatretus stouti: A scanning electron microscope study of vascular corrosion casts
Authors: Cecon Stephan , Minnich Bernd , Lametschwandtner Alois
Published: August 2002

The microvascularization of the brains of the hagfishes, Myxine glutinosa L. and Eptatretus stouti, were studied by scanning electron microscopy (SEM) of microvascular corrosion casts. Sections of these casts were used to determine the vascular territories of defined brain areas. Histological serial sections (10 μm) of the brains served for correlation of findings. Analysis of the microvascular casts of both species revealed that the blood supply to and from these brains arose ventrally and dorsally, respectively. Neither species possesses an arterial circle (Circulus Willisi) and both have similar microvascular patterns. The only difference between Myxine and Eptatretus was that the posterior cerebral artery in Myxine divides into mesencephalic and rhombencephalic branches, and in Eptatretus a third branch, termed telencephalic branch, arises from the posterior cerebral artery. 3D‐morphometry revealed that luminal diameters of: 1) intracerebral arteries and arterioles range from 35.11 ± 5.66 μm (mean ± SEM) in the hypothalamus to 92.69 ± 14.48 μm in the thalamus; 2) capillaries range from 17.8 ± 0.44 μm in the olfactory bulb to 21.70 ± 0.87 μm in the basal ganglia; and 3) intracerebral venules and veins range from 49.38 ± 4.17 μm in the hypothalamus to 75.58 ± 6.59 μm in the rhombencephalon. Interbranching distances of arteries and arterioles range from 179.19 ± 11.32 μm in the optic tectum to 235.19 ± 94.64 μm in the hypothalamus. Capillaries range from 91.07 ± 6.22 μm in the hypothalamus to 116.15 ± 9.45 μm in the thalamus, and venules and veins range from 137.30 ± 18.11 μm in the hypothalamus to 189.83 ± 17.47 μm in the optic tectum. Intervascular distances range from 70.58 ± 3.58 μm in the olfactory bulb to 89.52 ± 5.74 μm in the optic tectum. Branching angles of arteries and arterioles range from 38.39 ± 10.9° in the olfactory bulb to 100.73 ± 9.4° in the optic tectum, and the branching angles of capillaries range from 74.40 ± 5.42° in the optic tectum to 90.24 ± 4.66° in the olfactory bulb. Finally, the branching angles of the venules and veins range from 67.84 ± 6.83° in the tegmentum of the mesencephalon to 92.30 ± 6.35° in the optic tectum. J. Morphol. 253:51–63, 2002. © 2002 Wiley‐Liss, Inc.
Morphological changes in the efferent ducts during the main phases of the reproductive cycle of birds
Authors: Aire Tom A.
Published: August 2002

The changes that take place in the efferent ducts during the major phases of the reproductive cycle of birds were studied morphologically using standard histological, morphometric, and ultrastructural methods in prepuberal, sexually mature and sexually active, and sexually mature but sexually inactive domestic fowl (Gallus domesticus), drake (Anas platyrhynchos), and guinea fowl (Numida meleagris). Profound structural and dimensional changes occurred in both segments (proximal and distal) of the efferent ducts and, in particular, in the nonciliated (Type I) cell of the proximal duct of sexually mature but inactive birds. The subapical tubulovacuolar system was markedly atrophic in nonciliated (Types I and II) cells and the numerous round dense globules of Type I cells that normally occurred in sexually active birds were replaced by fewer and more pleomorphic bodies containing lipofuscin granules in sexually resting birds. Lipid droplets, few and extremely large in inactive drakes but numerous and smaller in size in guinea fowls and domestic fowls, occurred in the Type I cell at both infra‐ and supranuclear levels of resting but not in prepuberal or sexually active birds. Ciliated cells in both segments of the ducts exhibited fewer and less profound phase‐dependent changes ultrastructurally. Generally, the Type I cells of the proximal efferent duct appeared to be more sensitive to androgen deprivation than the Type II cell of the distal efferent duct or ciliated cells in both ducts. These morphologically phase‐dependent features of the efferent ducts of birds may be used, together with or independent of testicular changes, in the determination of the status of the testis and epididymis of a male bird with regard to the reproductive cycle, especially in seasonally breeding species. J. Morphol. 253:64–75, 2002. © 2002 Wiley‐Liss, Inc.
Cine MRI using steady state free precession in the radial long axis orientation is a fast accurate method for obtaining volumetric data of the left ventricle
Authors: Bloomer Timothy N. , Plein Sven , Radjenovic Aleksandra , Higgins David M. , Jones Timothy R. , Ridgway John P. , Sivananthan Mohan U.
Published: August 2002

In this study we assessed the use of a steady state free precession (SSFP) cine sequence in a series of radially orientated long axis slices for the measurement of left ventricular volumes and mass. We validated the radial long axis approach in phantoms and ex vivo porcine hearts and applied it to normal volunteers and patients using the SSFP and turbo gradient‐echo (TGE) sequences. High quality images were obtained for analysis, and the measured volumes with radial long axis SSFP sequence correlated well with short axis TGE and SSFP volumes (r > 0.98). The best interobserver agreement for left ventricular volumes was obtained using SSFP in the long axis radial orientation (variability < 2.3%). We conclude that this combination of sequence and scan orientation has intrinsic advantages for image analysis due to the improved contrast and the avoidance of errors associated with the basal slice in the short axis orientation. J. Magn. Reson. Imaging 2001;14:685–692. © 2001 Wiley‐Liss, Inc.
Diffusion‐weighted imaging of the spinal cord: Interleaved echo‐planar imaging is superior to fast spin‐echo
Authors: Bammer Roland , Augustin Michael , Prokesch Rupert W. , Stollberger Rudolf , Fazekas Franz
Published: August 2002

Purpose

To compare and evaluate two novel diffusion‐weighted sequences, based either on fast spin‐echo (FSE) or interleaved echo‐planar imaging (EPI) methods, as potential tools for investing spinal cord abnormalities.

Materials and Methods

Following recent improvements, both interleaved EPI (IEPI) and FSE techniques could be alternative approaches for rapid diffusion‐weighted imaging (DWI). Therefore, a navigated diffusion‐weighted multishot FSE sequence and a fat‐suppressed navigated diffusion‐weighted IEPI sequence with local shimming capabilities were tested. Both methods were compared in a consecutive series of five healthy volunteers and five patients with suspected intramedullary lesions. The sequences were graded qualitatively as either superior, inferior, or equal in quality, and also quantitatively by measuring the amount of ghosting artifacts in the background. Quantitative measurements of the diffusion coefficients within the spine were included.

Results

The overall image quality of IEPI was superior to FSE. Two out of five FSE scans were rated with poor image quality, whereas all IEPI scans were of sufficient quality. The ghosting levels ranged from approximately 3.3% to 6.2% for IEPI and from approximately 7.5% to 18.9% for FSE. Diffusion coefficients measured in healthy volunteers were similar for both IEPI and FSE, but showed higher fluctuations with the FSE technique.

Conclusion

Despite potential advantages of FSE, the IEPI technique is preferable for DWI applications in the spinal cord. J. Magn. Reson. Imaging 2002;15:364–373. © 2002 Wiley‐Liss, Inc.
Comparison of the threshold for peripheral nerve stimulation during gradient switching in whole body MR systems
Authors: Den Boer Jacques A. , Bourland Joe D. , Nyenhuis John A. , Ham Cornelis L.G. , Engels Johan M.L. , Hebrank Franz X. , Frese Georg , Schaefer Daniel J.
Published: August 2002

Purpose:

To compare thresholds for peripheral nerve stimulation from gradient switching in whole body magnetic resonance (MR) equipment of different design.

Materials and Methods:

Threshold data obtained in three experiments were reformatted into a single joint data set describing thresholds for anterio‐posterior (AP) gradient orientation and Echo Planar Imaging (EPI) waveforms with bipolar ramp times between 0.07 and 1.2 ms. Reformatting included the use of: a) the rate of change of the maximum field in the patient space as a measure of gradient output, b) lowest observable thresholds, c) lognormal distribution of thresholds, and d) equal standard deviation (SD) of all samples.

Results:

The joint data fit a hyperbolic threshold function. The residues were not significantly different between experiments.

Conclusion:

When expressed in appropriate format, the thresholds for peripheral nerve stimulation in volunteers for whole body MR equipment can be described with a hyperbolic threshold curve with rheobase 18.8 ± 0.6 Tesla/second and chronaxie 0.36 ± 0.02 milliseconds. J. Magn. Reson. Imaging 2002;15:520–525. © 2002 Wiley‐Liss, Inc.
Contrast‐enhanced coronary MR angiography: Relationship between coronary artery delineation and blood T1
Authors: Zheng Jie , Li Debiao , Cavagna Friedrich M. , Harris Katherine , Klocke Francis J. , Maggioni Fabio , Carr James , Simonetti Orlando , Laub Gerhard , Finn J. Paul
Published: August 2002

Contrast‐enhanced coronary angiography has become an important technique for magnetic resonance (MR) coronary artery imaging. However, the relationship between the quality of the coronary artery images and blood T1 has not yet been fully explored. In this paper, we assessed this relationship in an animal model by using a prototypical blood pool agent. With accumulated injections of this agent, the blood T1 would be maintained at different levels. The measured blood T1 values in vivo were 147 ± 3, 82 ± 6, 48 ± 4, 40 ± 3, and 30 ± 8 msec (N = 7). Fixed and variable flip angle schemes were used in coronary artery imaging. The signal to noise ratios (SNR) of coronary arteries were measured and the image quality was assessed. It was found that blood T1 less than 80 msec might be desired. No statistically significant difference was observed between two flip angle schemes. There was better vessel definition using variable flip angle at blood T1 lower than 50 msec. Understanding this relationship may be beneficial to optimizing image protocol and/or design of blood pool contrast agents for contrast‐enhanced coronary angiography. J. Magn. Reson. Imaging 2001;14:348–354. © 2001 Wiley‐Liss, Inc.
Probing protein stabilization by glycerol using electrospray mass spectrometry
Authors: Grandori Rita , Matecko Irena , Mayr Petra , Müller Norbert
Published: August 2002

This study shows that electrospray ionization mass spectrometry (ESI‐MS), combined with a heated turbo ion‐spray interface, allows monitoring protein stabilization by glycerol in solution. Measurements obtained with the two proteins lysozyme and cytochrome c are presented. The observed mass‐to‐charge (m/z) distributions reveal the stabilizing effect of the additive on the protein conformations against temperature and acid‐induced unfolding, as well as against denaturation by acetonitrile. The data obtained with lysozyme allow detection of minor conformational changes upon glycerol addition to the native protein, and suggest that the protein structure in the presence of the additive is slightly compressed compared with its state in water. This result corroborates previous evidence obtained by nuclear magnetic resonance. It is also shown that analysis of the m/z distributions obtained by ESI‐MS can lead to detection of partially folded and partially populated states in protein samples. Copyright © 2001 John Wiley & Sons, Ltd.
State of HBV DNA in HBsAg‐negative, anti‐HCV‐positive hepatocellular carcinoma: Existence of HBV DNA possibly as nonintegrated form with analysis by Alu‐HBV DNA PCR and conventional HBV PCR
Authors: Kawai Shigenobu , Yokosuka Osamu , Imazeki Fumio , Maru Yasushi , Saisho Hiromitsu
Published: August 2002

The role of hepatitis B virus (HBV) in carcinogenesis of hepatitis B surface antigen (HBsAg)‐negative, anti‐hepatitis C virus (anti‐HCV)‐positive hepatocellular carcinoma (HCC) remains unknown. To investigate the state of HBV DNA in such HCC, HBV DNA was examined by polymerase chain reaction (PCR) between HBV DNA and human Alu sequence (HBV‐Alu PCR), which could detect integrated form of HBV DNA only, and by conventional HBV PCR, which could detect both integrated and episomal forms of HBV DNA. In all the 17 HBsAg‐positive HCC, HBV DNA was detected by both HBV‐Alu PCR method and conventional HBV PCR method. By contrast, in HBsAg‐negative, anti‐HCV‐positive cases, HBV DNA was detected in 10 of 21 (47.6%) by conventional HBV PCR and in none of 21 (0%) by HBV‐Alu PCR method. Thus, integrated form of HBV DNA was not found in most HbsAg‐negative, anti‐HCV‐positive HCC in the current study. The role of episomal form of HBV DNA requires further investigation of its involvement in the process of the development of HBsAg‐negative, anti‐HCV‐positive HCC. J. Med. Virol. 64:410–418, 2001. © 2001 Wiley‐Liss, Inc.
Effect of lack of Interleukin‐4, Interleukin‐12, Interleukin‐18, or the Interferon‐γ receptor on virus replication, cytokine response, and lung pathology during respiratory syncytial virus infection in mice
Authors: Boelen Anita , Kwakkel Joan , Barends Marion , de Rond Lia , Dormans Jan , Kimman Tjeerd
Published: August 2002

RSV is an important cause of bronchiolitis in infants. Immunopathology may play a role in RSV‐induced bronchiolitis and severe RSV‐induced disease has been associated with a Th2 type immune response. The aim of the study was to identify cytokine pathways that are crucial in influencing RSV‐induced disease. For that purpose we inoculated IFNγR−/−, IL‐12−/−, IL‐18−/−, or IL‐4−/− mice with RSV. We observed that an RSV infection resulted in a predominant Th1 cytokine response associated with slight bronchiolitis and alveolitis. Pulmonary histopathology was only aggravated in IFN R−/− mice, characterised by eosinophilic influx around the bronchioles. Despite subtle changes in cytokine expression, no differences in histopathology were observed in IL‐12−/− and IL‐18−/− mice. Deficiency of IL‐4 has no effect on RSV‐induced Th1 cytokines and pulmonary histopathology. IFNγ‐receptor deficiency during primary RSV infection resulted in a disturbed Th1 response based on increased IL‐4, IL‐5, and IL‐13 expression and the presence of eosinophils in the lungs. It is concluded that IFNγ signalling is required for a pronounced Th1 response to RSV while IL‐12 and IL‐18 are not. A shift in the balance between Th1 and Th2 towards a Th2 response induced by missing IFNγ signalling leads to aggravated pulmonary pathology. This is not caused by enhanced viral load. J. Med. Virol. 66:552–560, 2002. © 2002 Wiley‐Liss, Inc.