bluuebunny/crossref_metadata_2025 huggingface dataset:
Preoperative evaluation of periampullary tumors by endoscopic sonography, transabdominal sonography, and computed tomography
Authors: Chen Chien‐Hua , Tseng Li‐Jung , Yang Chi‐Chieh , Yeh Yung‐Hsiang
Published: August 2002

Purpose

The purpose of this retrospective study was to compare the sensitivity of endoscopic sonography (EUS), transabdominal sonography (US), and CT in the detection of, local staging of, and prediction of vascular involvement by or distant metastasis from periampullary tumors.

Methods

Seventy‐four consecutive patients with presumed periampullary tumors were evaluated by EUS, US, and CT during a 3.25‐year period. The local staging accuracy of the modalities was assessed in the 36 patients with solid tumors who underwent surgery. The sensitivity of the modalities in predicting vascular involvement and distant metastasis was assessed in the 56 patients with carcinomas.

Results

EUS was the most sensitive modality in the detection (EUS, 97%; US, 24%; and CT, 39%; p < 0.001 for EUS versus US or CT) and T classification (EUS, 72%; US, 11%; CT, 22%; p < 0.001 for EUS versus US or CT) of periampullary tumors. EUS also had better sensitivity than US in detecting lymph node metastasis from periampullary cancers (EUS, 47%; US, 7%; and CT, 33%; p = 0.02 for EUS versus US; p = 0.7 for EUS versus CT). The accuracy of EUS in determining the T classification (without stent, 81%; with stent, 65%) and N classification (without stent, 80%; with stent, 70%) tended to decrease in the presence of an endobiliary stent, but the differences were not significant. EUS was the most sensitive modality in demonstrating vascular involvement (EUS, 100%; US, 0%; and CT, 33%; p = 0.002 for EUS versus US; p = 0.03 for EUS versus CT) but was not significantly different in detecting distant metastasis (EUS, 11%; US, 44%; and CT, 44%).

Conclusions

EUS is superior to US and CT in the local assessment of periampullary tumors. The staging accuracy of EUS is minimally but not significantly affected by the presence of an endobiliary stent. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:313–321, 2001.
Homologies of process and modular elements of embryonic construction
Authors: Gilbert Scott F. , Bolker Jessica A.
Published: August 2002

There are several signal transduction pathways that integrate embryonic development. We find that both within species and between species, these pathways constitute homologous modules. The processes, themselves, can be considered homologous, just as structures can be considered homologous. Just like vertebrate limbs, these pathways are composed of homologous parts (in this case, the proteins of the pathway) that are organized in homologous ways. These pathways are conserved through evolutionary time, and they undergo descent with modification. Such homologies of processes become critical to the discussion of evolution and development when we consider (1) that evolution depends on heritable changes in development, (2) that development is modular such that different modules can change without affecting other modules, (3) that modules can be co‐opted into new functions, and (4) that modules depend on intercellular communication. J. Exp. Zool. (Mol. Dev. Evol.) 291:1–12, 2001. © 2001 Wiley‐Liss, Inc.
Effects of plasma from bivalve mollusk species on the in vitro proliferation of the protistan parasite Perkinsus marinus
Authors: Gauthier Julie D. , Vasta Gerardo R.
Published: August 2002

The in vitro culture of the Eastern oyster parasite Perkinsus marinus has provided a unique opportunity to examine its susceptibility to putative recognition and effector defense mechanisms operative in refractory bivalve species. In this study, we report the effect of supplementing the culture medium with plasma from: (1) uninfected to heavily infected Eastern oysters; (2) oyster species considered to be disease‐resistant; and (3) bivalve mollusk species that are naturally exposed to the parasite but show no signs of disease. We also examined in vitro the interaction between hemocytes from Crassostrea virginica and C. gigas and P. marinus trophozoites. Our results revealed a significant decrease (32%) in proliferation of P. marinus in the presence of plasma from heavily infected C. virginica oysters. The inhibitory effects were less pronounced with plasma from moderately infected and uninfected oysters. In contrast, plasma from C. rivularis and C. gigas enhanced P. marinus proliferation. Proliferation was significantly reduced in media supplemented with plasma from Mytilus edulis, Mercenaria mercenaria, and Anadara ovalis. The highest inhibitory activity was apparent in M. edulis, for which 5% plasma‐supplemented medium reduced growth by 35% relative to the controls. M. edulis active component(s) was heat‐stable, yet pronase‐sensitive. The significantly higher uptake of live P. marinus trophozoites by hemocytes from C. virginica, relative to those from C. gigas, suggests a certain level of specificity in the recognition/endocytosis of the parasite by its natural bivalve host species. J. Exp. Zool. 292:221–230, 2002. © 2002 Wiley‐Liss, Inc.
Egg‐jelly structure promotes efficiency of internal fertilization in the newt, Cynops pyrrhogaster
Authors: Itoh Tokuko , Kamimura Saori , Watanabe Akihiko , Onitake Kazuo
Published: August 2002

Egg‐jelly is composed of a network of fibrous components and contains substances regulating the sperm‐egg interaction. Many studies on the latter have been conducted, whereas the role of the egg‐jelly structure in fertilization has not yet been fully assessed. In this study, we examined the fertilization efficiency in the presence and absence of the structure around the egg of the newt, Cynops pyrrhogaster, using a gelatin gel system. Although de‐jellied eggs of C. pyrrhogaster can be fertilized with an adequate number of sperm, the fertilization rate was dramatically increased through the use of the gelatin gel. Sperm showed forward motility with straight morphology in the gel, whereas they swam in circles in solution. This result indicates that the gel structure is significant for sperm guidance to the egg surface, and its presence raises the fertilization efficiency in C. pyrrhogaster. When sperm were entangled in the gel structure, they were immediately folded and never showed any forward motility. Sperm with zigzag morphology were observed in the gelatin gel as well as in the egg‐jelly, indicating the elimination of sperm by the gel structure. The effect of sperm elimination on successful fertilization was estimated using gelatin gels of different thickness. Though the variation did not affect the fertilization rate, the rate of normal development gradually increased in the thicker gels. This result indicates that sperm elimination in egg‐jelly can function in the fertilization system. The roles of sperm guidance and sperm elimination under the physiological condition of internal fertilization of the newt are discussed. J. Exp. Zool. 292:314–322, 2002. © 2002 Wiley‐Liss, Inc.
Effects of the purified IGF‐I complex on the capacitation and acrosome reaction of rabbit spermatozoa
Authors: Minelli Alba , Liguori Lavinia , Collodel Giulia , Lattaioli Paolo , Castellini Cesare
Published: August 2002

A protein complex containing IGF‐I, purified from rabbit seminal plasma, was used to investigate its effects on the capacitation and acrosome reaction of rabbit spermatozoa. Uncapacitated sperm (Pattern F), capacitated sperm (Pattern B), and acrosome‐reacted sperm (Pattern AR) were determined by CTC staining, and the results were validated by PSA‐staining. The addition of the IGF‐I complex to the capacitative medium directed the spermatozoa to spontaneous acrosome reaction. On the other hand, IGF‐I complex, added to capacitated spermatozoa, acted as inducer of the acrosome reaction. Results of IVF experiments showed high rates of fertilization with capacitated spermatozoa, acrosome‐reacted by either A23187 or IGF I complex, whereas significantly lower rates were obtained with spermatozoa capacitated in the presence of IGF‐I complex. J. Exp. Zool. 290:311–317, 2001. © 2001 Wiley‐Liss, Inc.
Ultrastructure of sperm storage and male genital ducts in a male holocephalan, the elephant fish, Callorhynchus milii
Authors: Hamlett William C. , Reardon Matthew , Clark Joan , Walker Terence I.
Published: August 2002

In chondrichthyes, the process of spermatogenesis produces a spermatocyst composed of Sertoli cells and their cohort of associated spermatozoa linearly arrayed and embedded in the apical end of the Sertoli cell. The extratesticular ducts consist of paired epididymis, ductus deferens, isthmus, and seminal vesicles. In transit through the ducts, spermatozoa undergo modification by secretions of the extratesticular ducts and associated glands, i.e., Leydig gland. In mature animals, the anterior portion of the mesonephros is specialized as the Leydig gland that connects to both the epididymis and ductus deferens and elaborates seminal fluid and matrix that contribute to the spermatophore or spermatozeugmata, depending on the species. Leydig gland epithelium is simple columnar with secretory and ciliated cells. Secretory cells have periodic acid‐Schiff positive (PAS+) apical secretory granules. In the holocephalan elephant fish, Callorhynchus milii, sperm and Sertoli cell fragments enter the first major extratesticular duct, the epididymis. In the epididymis, spermatozoa are initially present as individual sperm but soon begin to laterally associate so that they are aligned head‐to‐head. The epididymis is a highly convoluted tubule with a small bore lumen and an epithelium consisting of scant ciliated and relatively more secretory cells. Secretory activity of both the Leydig gland and epididymis contribute to the nascent spermatophores, which begin as gel‐like aggregations of secretory product in which sperm are embedded. Fully formed spermatophores occur in the ductus. The simple columnar epithelium has both ciliated and secretory cells. The spermatophore is regionalized into a PAS+ and Alcian‐blue‐positive (AB+) cortex and a distinctively PAS+, and less AB+ medulla. Laterally aligned sperm occupy the medulla and are surrounded by a clear zone separate from the spermatophore matrix. Grossly, the seminal vesicles are characterized by spiral partitions of the epithelium that project into the lumen, much like a spiral staircase. Each partition is staggered with respect to adjacent partitions while the aperture is eccentric. The generally nonsecretory epithelium of the seminal vesicle is simple columnar with both microvillar and ciliated cells. J. Exp. Zool. 292:111–128, 2002. © 2002 Wiley‐Liss, Inc.
Radiohalogenated carbohydrates for use in PET and SPECT
Authors: Adam Michael J.
Published: August 2002

Radiohalogenated carbohydrates have been of significant interest to the Nuclear Medicine community since the success of 2‐Deoxy‐2‐fluoro‐glucose (FDG)/positron emission tomography (PET) to measure glucose metabolic rates in humans. This review of this important class of compounds will be written in two parts, and will concentrate on the chemistry. The first part will cover the development of FDG, the many attempts to synthesize other radiohalogenated PET and SPECT analogs, and future prospects of a SPECT analog. The second will cover the synthesis of other radio‐halogenated carbohydrate compounds such as nucleosides, where the halogen is located on the sugar rings, as potential imaging or therapeutic agents. Copyright © 2002 John Wiley & Sons, Ltd.
Breath‐hold three‐dimensional true‐FISP imaging of coronary arteries using asymmetric sampling
Authors: Deshpande Vibhas S. , Shea Steven M. , Chung Yiu Cho , McCarthy Richard M. , Finn J. Paul , Li Debiao
Published: August 2002

Purpose

To evaluate the feasibility of using asymmetric sampling in a three‐dimensional, magnetization‐prepared, segmented true‐FISP (fast imaging with steady‐state precession) sequence in order to reduce the sensitivity to resonance offsets, while simultaneously improving imaging speed.

Materials and Methods

Asymmetric sampling reduces the repetition time, leading to reduced resonance offset effects and improved resolution in a fixed imaging time. However, it introduces additional phase terms due to blood flow, which can cause image artifacts. Computer simulations were performed to study the off‐resonance and flow effects of asymmetric sampling in true‐FISP. Coronary artery imaging was performed in healthy volunteers.

Results

Simulations and volunteer studies show that image artifacts due to flow‐induced phase variations may be acceptable at low velocities. Volunteer studies demonstrate that relatively high‐resolution coronary artery images can then be acquired within a single breath‐hold with segmented three‐dimensional true‐FISP imaging using data asymmetry in the readout direction.

Conclusion

Asymmetric sampling is a useful modification to true‐FISP for reducing the off‐resonance artifacts and improving imaging speed when the flow velocities are small. J. Magn. Reson. Imaging 2002;15:473–478. © 2002 Wiley‐Liss, Inc.
Pelvic lymph node visualization with MR imaging using local administration of ultra‐small superparamagnetic iron oxide contrast
Authors: McCauley Thomas R. , Rifkin Matthew D. , Ledet Cheryl A.
Published: August 2002

Purpose

To determine if interstitial injection of iron oxide particles improves visualization of pelvic lymph nodes at magnetic resonance imaging (MRI) and to determine the effect of injection site on location of visualized nodes.

Materials and Methods

In nine healthy volunteers, ferumoxtran‐10 iron oxide (0.28 mg iron per kg) was injected into the anterior thigh (three subjects) or perianal (three subjects) or periprostatic tissues (three subjects). MRI at 1.5 T was performed before injection and one, three, and seven days after injection.

Results

The mean of 30 nodes seen post‐injection was greater than the mean of 5.8 seen pre‐injection (P < 0.001). After thigh injection, a mean of three internal vs. 36 external nodes were seen. Compared with thigh injection, there was a higher fraction of internal nodes with perianal (mean of nine internal vs. 14 external, P < 0.001) and periprostatic injection (mean of 11 internal vs. five external, P < 0.001). More nodes were seen with gradient‐echo sequences than with other sequences (P < 0.001).

Conclusion

Interstitial injection of iron oxide particles increases visualization of pelvic lymph nodes. Perianal and periprostatic injection increases the number of internal pelvic lymph nodes seen compared with thigh injection. J. Magn. Reson. Imaging 2002;15:492‐497. © 2002 Wiley‐Liss, Inc.
Effects of indomethacin on cerebral blood flow at rest and during hypercapnia: An arterial spin tagging study in humans
Authors: St. Lawrence Keith S. , Ye Frank Q. , Lewis Bobbi K. , Weinberger Daniel R. , Frank Joseph A. , McLaughlin Alan C.
Published: August 2002

Purpose

To investigate using an arterial spin tagging (AST) approach the effect of indomethacin on the cerebral blood flow (CBF) response to hypercapnia.

Materials and Methods

Subjects inhaled a gas mixture containing 6% CO2 for two 5‐minute periods, which were separated by a 10‐minute interval, in which subjects inhaled room air. In six subjects, indomethacin (i.v., 0.2 mg/kg) was infused in the normocapnic interval between the two hypercapnic periods.

Results

Indomethacin reduced normocapnic gray matter CBF by 36 ± 5% and reduced the CBF increase during hypercapnia from 43 ± 9% to 16 ± 5% in gray matter (P < 0.001) and from 48 ± 11% to 35 ± 9% in white matter (P < 0.025).

Conclusion

The results demonstrate that an AST approach can measure the effects of indomethacin on global CBF increases during hypercapnia and suggest that an AST approach could be used to investigate pharmacological effects on focal CBF increases during functional activation. J. Magn. Reson. Imaging 2002;15:628–635. Published 2002 Wiley‐Liss, Inc.
Staging endometrial cancer: Role of magnetic resonance imaging
Authors: Frei Kathrin A. , Kinkel Karen
Published: August 2002

This review article summarizes and comments the role of magnetic resonance imaging (MRI) in the management of endometrial cancer. The MRI technique, appearance, and diagnostic criteria of endometrial carcinoma are discussed. The value of MRI in the preoperative staging of endometrial cancer is compared to alternative strategies. Contrast‐enhanced MRI performs best in the pretreatment evaluation of myometrial or cervical invasion, compared to ultrasonography (US), computed tomography (CT), or nonenhanced MRI. The overall costs and accuracy are similar to those of the current methods of staging, including intraoperative gross dissection of the uterus. In addition, results of MRI might decrease the number of unnecessary lymph node dissections. J. Magn. Reson. Imaging 2001;13:850–855. © 2001 Wiley‐Liss, Inc.
Use of L‐[15N] glutamic acid and homoglutathione to determine both glutathione synthesis and concentration by gas chromatography‐mass spectrometry (GCMS)
Authors: Humbert Bernard , Nguyen Patrick , Obled Christiane , Bobin Christine , Vaslin Anne , Sweeten Shawn , Darmaun Dominique
Published: August 2002

A method for simultaneous measurement of both glutathione enrichment and concentration in a biological sample using gas chromatography mass spectrometry is described. The method is based on the preparation of N,S‐ethoxycarbonylmethyl ester derivatives of glutathione, and the use of homoglutathione (glutamyl–cysteinyl–alanine) as an internal standard. A procedure for determination of glutamate concentration and enrichment is also reported. Both methods have within‐day and day‐to‐day inter‐assay coefficients of variation less than 5%, and recoveries of known added amounts of glutathione and glutamate are close to 100%. Taken together, these methods allowed determination of glutathione concentration and fractional synthesis rate in red blood cells using L‐[15N] glutamic acid infusion. This approach was applied in vivo to investigate the effects of a 72 h fast, compared with a control overnight fast, on erythrocyte glutathione in a single dog. The 72 h fast was associated with a 39% decline in erythrocyte glutathione level, (2.9 ± 0.4 versus 4.7 ± 0.5 mmol l−1, fasting versus control) with no change in glutathione fractional synthesis (67.4 versus 71.3% d−1, fasting versus control). Copyright © 2001 John Wiley & Sons, Ltd.
Liquid chromatographic/mass spectrometric detection of the 3‐(3‐hydroxyalkanoyloxy) alkanoic acid precursors of rhamnolipids in Pseudomonas aeruginosa cultures
Authors: Lépine François , Déziel Eric , Milot Sylvain , Villemur Richard
Published: August 2002

A series of pseudomolecular and fragment ions attributed to 3‐(3‐hydroxyalkanoyloxy)alkanoic acids (HAAs) were detected by liquid chromatography/mass spectrometry among the rhamnolipids observed in a Pseudomonas aeruginosa strain 57RP supernatant. The fragmentation mechanism leading to the formation of the fragment ions was determined by a deuterium exchange experiment and by using a standard HAA mixture obtained from the mild acidic hydrolysis of rhamnolipids of known composition. The structure and the response factor of these free HAAs were determined. The HAAs relative composition differs between free HAAs and those present in rhamnolipids, the former being enriched in lower molecular mass congeners and depleted in the heavier ones. Within an isomeric pair, the isomer with the shortest 3‐hydroxyalkaloyl residue at the hydroxyl end was more abundant than the one with the heavier 3‐hydroxyalkaloyl acid at this position, and the ratios of their relative abundances were similar for free HAAs and those in rhamnolipids. Experiments with deuterium‐labeled rhamnolipids demonstrated that free HAAs are part of a pool used for rhamnolipid biosynthesis and are not rhamnolipid degradation products. Copyright © 2001 John Wiley & Sons, Ltd.
Selective incorporation of isotopically labeled amino acids for identification of intact proteins on a proteome‐wide level
Authors: Martinović Suzana , Veenstra Timothy D. , Anderson Gordon A. , Paša‐Tolić Ljiljana , Smith Richard D.
Published: August 2002

The post‐genomic era and increased demands for broad proteome measurements have greatly increased the needs for protein identification. We describe a strategy that uses accurate mass measurements and partial amino acid content information to unambiguously identify intact proteins, and show its initial application to the proteomes of Escherichia coli and Saccharomyces cerevisiae. Proteins were extracted from the organisms grown in minimal medium or minimal medium to which isotopically labeled leucine (Leu‐D10) had been added. The two protein extracts were mixed and analyzed by capillary isoelectric focusing (CIEF) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR). The incorporation of the isotopically labeled residue has no effect on the CIEF separation of proteins, and both isotopically labeled and unlabeled versions of specific proteins are observed within the same mass spectrum. The difference in the mass of the unlabeled and labeled proteins is used to determine the number of Leu residues present in a particular protein. Proteins can then often be unambiguously identified based on their accurately determined molecular mass and the additional constraint provided by number of Leu residues. The identities of proteins were further confirmed by repeating CIEF/FTICR measurements with samples that contain other isotopically labeled amino acid residues (e.g. His, Arg, Ile, Phe, Lys). A theoretical study of the amino acid composition (for a difference in the amino acid sequence) showed the constraints needed in order to identify the protein unambiguously. Additionally, the mass differences between the predicted and the experimental accurate mass measurement provide insights into the nature of simple post‐translational modifications. Copyright © 2001 John Wiley & Sons, Ltd.
Community‐based seroepidemiological survey of HCV infection in Catalonia, Spain
Authors: Domínguez Àngela , Bruguera Miquel , Vidal Josep , Plans Pere , Salleras Lluís
Published: August 2002

The objective of this study was to investigate the prevalence of antibodies against the hepatitis C virus (anti‐HCV) and the associated risk factors in a representative sample of the population of Catalonia, Spain. Serum samples from 2,142 subjects aged between 5 and 70 years, selected at random from urban and rural habitats, were studied. Multiple logistic regression analysis was carried out to determine variables associated independently with the presence of HCV antibodies. The age and gender standardized prevalence of anti‐HCV was 2.5% (95% confidence interval, 1.8–3.2). Prevalence increased significantly with age (P < 0.001), but no other sociodemographic variables were associated with HCV infection. Tattoos (OR: 6.2), blood transfusions (OR: 5.0) intravenous drug use (OR: 4.9) and antecedents of hospitalization (OR: 2.3) were variables associated independently with infection. HCV infection affects mainly elderly people in Spain and spares children and adolescents. This suggests that major exposure to HCV may have occurred many years ago, when infection was more widespread than in recent years. J. Med. Virol. 65:688–693, 2001. © 2001 Wiley‐Liss, Inc.
Viral vector‐mediated delivery of competing glycosyltransferases modifies epitope expression cell specifically
Authors: Baboval Thia , Liang ShuLing , Smith Frances I.
Published: August 2002

The glycoconjugate epitopes 3‐fucosyl‐N‐acetyllactosamine (CD15) and sulfoglucuronylcarbohydrate (SGC) mediate cell adhesion events in several systems, and are regulated both spatially and temporally during cerebellar development. In cotransfection studies using COS‐1 cells, competition between glycosyltransferases that utilize a common precursor involved in the final synthetic steps of these epitopes, can modulate epitope expression. For example, cotransfection of rat α1,3‐fucosyltransferase IV (Fuc‐TIV) and either rat glucuronic acid transferase P (GlcAT) or pig α1,3‐galactosyltransferase (GalT) resulted in the dominance of either SGC or GalαGal epitope expression, respectively, with blockage of CD15 epitope expression. Viral vectors expressing these glycosyltransferases were used to determine whether competition plays a role in establishing epitope dominance in cerebellar cells, and whether overexpression of competing glycosyltransferases could be used to block epitope expression. Infection of cerebellar astrocytes with viral vectors expressing either Fuc‐TIV, or Fuc‐TIX, caused dramatic increases in CD15 expression in the presence of continued endogenous SGC epitope expression. Likewise, viral transduction with GalT resulted in GalαGal expression without affecting endogenous CD15 or SGC expression. Thus, competition between these enzymes does not appear to play a role in establishing epitope expression in astrocytes, and transduction of these enzymes does not provide a method of blocking the expression of endogenous epitopes. In contrast to what was observed for astrocytes, infection with viral vectors expressing either Fuc‐T, GlcAT, or GalT did not result in significant expression of the relevant epitopes (CD15, SGC or GalαGal, respectively) on granule neurons. These results suggest a different complement of precursors are present in granule neurons and astrocytes, presumably due to the presence of different complements of glycosyltransferases in these cells. © 2002 Wiley‐Liss, Inc.
Identification of neuronal cell lineage‐specific molecules in the neuronal differentiation of P19 EC cells and mouse central nervous system
Authors: Kotani Masaharu , Osanai Taka , Tajima Youichi , Kato Hiroko , Imada Masato , Kaneda Hideki , Kubo Hideo , Sakuraba Hitoshi
Published: August 2002

P19 embryonic carcinoma (EC) cells are one of the simplest systems for analyzing the neuronal differentiation. To identify the membrane‐associated molecules on the neuronal cells involved in the early neuronal differentiation in mice, we generated two monoclonal antibodies, SKY‐1 and SKY‐2, by immunizing rats with a membrane fraction of the neuronally committed P19 EC cells as an antigen. SKY‐1 and SKY‐2 recognized the carbohydrate moiety of a 90 kDa protein (RANDAM‐1) and the polypeptide core of a 40 kDa protein (RANDAM‐2), respectively. In the P19 EC cells, the expression of RANDAM‐1 was colocalized to a part of Nestin‐positive cells, whereas that of RANDAM‐2 was observed in most Nestin‐positive cells as well as β‐III‐tubulin positive neurons. In the embryonic and adult brain of mice, RANDAM‐1 was expressed at embryonic day 8.5 (E8.5), and the localization of antigen was restricted on the neuroepithelium and choroid plexus. The RANDAM‐2 expression commenced at E6.0, and the antigen was distributed not only on the neuroepithelium of embryonic brain but on the neurons of adult brain. Collectively, it was concluded that RANDAM‐1 is a stage specific antigen to express on the neural stem cells, and RANDAM‐2 is constitutively expressed on both the neural stem cells and differentiated neuronal cells in mouse central nervous system (CNS). © 2002 Wiley‐Liss, Inc.
Erythropoietin protects neurons against chemical hypoxia and cerebral ischemic injury by up‐regulating Bcl‐xL expression
Authors: Wen Tong‐Chun , Sadamoto Yasutaka , Tanaka Junya , Zhu Peng‐Xiang , Nakata Kimihiko , Ma Yong‐Jie , Hata Ryuji , Sakanaka Masahiro
Published: August 2002

Erythropoietin (EPO) promotes neuronal survival after cerebral ischemia in vivo and after hypoxia in vitro. However, the mechanisms underlying the protective effects of EPO on ischemic/hypoxic neurons are not fully understood. The present in vitro experiments showed that EPO attenuated neuronal damage caused by chemical hypoxia at lower extracellular concentrations (10−4–10−2 U/ml) than were previously considered. Moreover, EPO at a concentration of 10−3 U/ml up‐regulated Bcl‐xL mRNA and protein expressions in cultured neurons. Subsequent in vivo study focused on whether EPO rescued hippocampal CA1 neurons from lethal ischemic damage and up‐regulated the expressions of Bcl‐xL mRNA and protein in the hippocampal CA1 field of ischemic gerbils. EPO was infused into the cerebroventricles of gerbils immediately after 3 min of ischemia for 28 days. Infusion of EPO at a dose of 5 U/day prevented the occurrence of ischemia‐induced learning disability. Subsequent light microscopic examinations showed that pyramidal neurons in the hippocampal CA1 field were significantly more numerous in ischemic gerbils infused with EPO (5 U/day) than in those receiving vehicle infusion. The same dose of EPO infusion caused significantly more intense expressions of Bcl‐xL mRNA and protein in the hippocampal CA1 field of ischemic gerbils than did vehicle infusion. These findings suggest that EPO prevents delayed neuronal death in the hippocampal CA1 field, possibly through up‐regulation of Bcl‐xL, which is known to facilitate neuron survival. © 2002 Wiley‐Liss, Inc.
Slow axonal transport of the cytosolic chaperonin CCT with Hsc73 and actin in motor neurons
Authors: Bourke Gregory J. , El Alami Wathik , Wilson Suzanne J. , Yuan Aidong , Roobol Anne , Carden Martin J.
Published: August 2002

Molecular chaperones are well known for their role in facilitating the folding of nascent and newly synthesized proteins, but have other roles, including the assembly, translocation and renaturation of intracellular proteins. Axons are convenient tissues for the study of some of these other roles because they lack the capacity for significant protein synthesis. We examine the axonal transport of the cytosolic chaperonin containing T‐ complex polypeptide 1 (CCT) by labeling lumbar motor neurons with [35S]methionine and examining sciatic nerve proteins by 2‐D gel electrophoresis and immunoblotting. All CCT subunits identifiable with specific antibodies, namely CCTα, CCTβ, CCTγ and CCTϵ/CCTθ (the latter two subunits colocalized in analyses of rat nerve samples), appeared to be labeled in “slow component b” of axonal transport along with the molecular chaperone Hsc73 and actin, a major folding substrate for CCT. Our results are consistent with molecular chaperones having a post‐translational role in maintaining the native form of actin during its slow transport to the axon terminal and ensuring its correct assembly into microfilaments. © 2002 Wiley‐Liss, Inc.
Subcellular localization and detergent solubility of MVP17/rMAL, a lipid raft‐associated protein in oligodendrocytes and myelin
Authors: Kim Taeyoon , Pfeiffer Steven E.
Published: August 2002

Detergent‐insoluble, glycosphingolipid‐cholesterol‐enriched microdomains (lipid rafts) have been implicated in both protein trafficking and signal transduction. Previously we identified in oligodendrocytes and myelin the lipid raft‐associated, integral membrane protein myelin vesicular protein of 17 kDa (MVP17)/rMAL. Here we have examined the subcellular localization and/or detergent insolubility of native and recombinant MVP17/rMAL in transfected oligodendrocytes and COS‐7 cells and purified myelin. Consistent with our previous report regarding the insolubility of MVP17/rMAL in the zwitterionic detergent 3‐[(3‐chloramidopropyl)‐dimethylammonio]‐1‐propane‐sulfonate (CHAPS), MVP17/rMAL from purified myelin and oligodendrocytes in culture was mostly insoluble upon extraction at 4°C with the non‐ionic detergent Triton X‐100 and floated to a low density in sucrose gradient ultracentrifugation, but became detergent soluble at 37°C. Data obtained by immunofluorescence microscopy of the expression of epitope‐tagged MVP17/rMAL transfected into oligodendrocytes and COS‐7 cells were consistent with a model in which both the N‐ and C‐termini of this protein face the cytoplasm. Mutational analysis identified domains of MVP17/rMAL important for its subcellular localization and for its detergent solubility profile. In particular, insertional mutagenesis of loop II prevented the insertion of the mutant protein into the plasma membrane of COS‐7 cells and rendered it insoluble in TX‐100. Expression of full‐length constructs of MVP17/rMAL in COS‐7 cells resulted in an enlargement of transfected COS‐7 cells, consistent with a proposed role of rMAL in vesicular trafficking. © 2002 Wiley‐Liss, Inc.
Apoptotic death following Fas activation in human oligodendrocyte hybrid cultures
Authors: Li Weiping , Maeda Yasuhiro , Ming Xue , Cook Stuart , Chapin John , Husar Walter , Dowling Peter
Published: August 2002

The purpose of this study was to determine how oligodendrocytes die following Fas receptor activation. An immortalized human oligodendrocyte hybrid line (MO3.13) was challenged with Fas ligand (FasL), and cell death was assessed by flow cytometry and DNA gel electrophoresis. Caspase activation was determined by either Western immunoblotting on cell extracts or by whole‐cell flow cytometry. FasL challenge clearly induced substantial apoptotic cell death in the oligodendrocyte hybrid cell line, as judged by flow cytometry and by the presence of prominent low molecular weight DNA banding patterns after gel electrophoresis. Western immunoblots showed marked increases in cleaved caspase‐1, 8, and 3, indicating that the extrinsic Fas death receptor‐induced pathway was activated. The intrinsic mitochondrial pathway was also activated, but only at a minimal level. These findings demonstrate that there are several independent molecular sites within the extrinsic caspase cascade in oligodendrocytes where inhibitory compounds may be capable of blocking cell death in vivo. Published 2002 Wiley‐Liss, Inc.
Blood–brain barrier preservation in the in vitro isolated guinea pig brain preparation
Authors: Librizzi Laura , Janigro Damir , De Biasi Silvia , de Curtis Marco
Published: August 2002

The morphofunctional preservation of the blood–brain barrier (BBB) was evaluated in the isolated guinea pig brain maintained in vitro by arterial perfusion. Electron microscopy evaluation after 5 hr in vitro demonstrated that cerebral capillaries and BBB specializations in this preparation retain features compatible with structural integrity. BBB‐impermeable and ‐permeable atropine derivatives arterially perfused to antagonize carbachol‐induced fast oscillatory activity confirmed the functional preservation of the BBB in vitro. To study BBB function further, changes in extracellular K+ concentration during arterial perfusion of a high‐K+ solution were measured with K+‐sensitive electrodes positioned in the cortex and, as control, at the brain venous outlet, where the solution perfused through the brain arterial system was collected. After 5 hr in vitro, the [K+]o values measured during high‐K+ perfusion in the piriform and entorhinal cortices were 5.02 ± 0.17 mM (mean ± SE) and 5.2 ± 0.21 mM, respectively (n = 6). Coperfusion of the high‐K+ solution with the Na+/K+ pump blocker ouabain (10 μM; n = 4) induced consistently spreading depression preceded by a rise in [K+]o. Finally, sporadic, isolated spots of extravasation of the fluorescent marker fluorescein isothiocyanate (FITC)‐dextran preferentially circumscribed to deep cortical layers was observed in brains perfused with FITC‐dextran after 5 hr in vitro. The study demonstrates that the in vitro isolated guinea pig brain is viable for studying cerebrovascular interactions and BBB permeability of compounds active in the central nervous system. J. Neurosci. Res. 66:289–297, 2001. © 2001 Wiley‐Liss, Inc.
Prospects for improved seasonal predictions of monsoon precipitation over Sahel
Authors: Garric G. , Douville H. , Déqué M.
Published: August 2002

Long‐range forecasting is a notoriously difficult area that has received increased attention in recent years. Both statistical and dynamical methods have been proposed, which are all based on the assumption that the atmospheric variability is influenced on the seasonal time scale by lower boundary forcings such as the sea surface temperature (SST) or the continental hydrology. Whereas dynamical predictions rely on the explicit simulation of major atmospheric processes, it is still unclear that they lead to better estimations of seasonal precipitation anomalies on the regional scale. In the present study, both forecasting strategies are used to predict monsoon rainfall anomalies over Central Sahel. The statistical predictions are based on linear regressions using SST and rainfall predictors observed over 1968–97, a relatively dry period compared with the whole 20th century. The dynamical predictions are based on ten‐member ensembles of seasonal hindcasts using the ARPEGE atmospheric model forced by observed SST over the 1979–93 period. The results suggest that the ARPEGE precipitation forecasts are less skilful than a linear regression scheme based on only two predictors. However, the atmospheric model shows a better ability to simulate the variability of the large‐scale monsoon circulation. As a consequence, a simple statistical adaptation of the ARPEGE dynamical predictions is feasible and leads to better predictions of the rainfall anomalies than the direct use of the modelled precipitation. Finally, a statistico‐dynamical method is proposed, based on a multivariate regression using both observed predictors and ARPEGE dynamical outputs. Although based on too short a time‐series to lead to definitive conclusions, the results are encouraging and suggest the need to combine dynamical and statistical tools to perform efficient seasonal predictions. Copyright © 2002 Royal Meteorological Society.
The manganese complex of 2,3,7,8,12,13,17,18-octaphenylporphyrin as epoxidation catalyst
Authors: SOBRAL ABÍLIO J. F. N. , GONSALVES ANTÓNIO M. D'A. ROCHA
Published: August 2002

The 2,3,7,8,12,13,17,18-octaphenylporphyrinato manganese(III) chloride was prepared and its behaviour as epoxidation catalyst was studied. The role of the phenyl substituents in the ß-pyrrolic positions concerning the stability of the catalyst to the reaction conditions and the efficiency and selectivity of the oxidations was accessed in a comparative study with MnTPP and MnEtio II.
Spectroscopic study of partially ordered semiconductor heterojunction under high pressure and high magnetic field
Authors: Yu P. Y. , Martinez G. , Zeman J. , Uchida K.
Published: August 2002

Photoluminescence upconversion (PLU) is a phenomenon in which a sample emits photons with energy higher than that of the excitation photon. This effect has been observed in many materials, including rare earth ions doped in insulating hosts and semiconductor heterostructures without using high‐power lasers as the excitation source. Recently this effect has been observed also in partially CuPt‐ordered GaInP2 epilayers grown on GaAs substrates. As a spectroscopic technique, PLU is particularly well suited for studying band alignment at heterojunction interfaces. The value of band offset has been determined with meV precision using magneto‐photoluminescence. Using the fact that the pressure coefficient of electrons in GaAs is higher than that in GaInP2 we have been able to ‘manipulate’ the band offset at the GaInP/GaAs interface. By converting the band offset from type I to type II we were able to demonstrate that the efficiency of the upconversion process is greatly enhanced by a type II band offset. Copyright © 2001 John Wiley & Sons, Ltd.
Isotope effect on Raman spectra of polycrystalline La0.67Ca0.33MnO3
Authors: Zhang P. X. , Huang S. J. , Habermeier H. U. , Zhao G. M.
Published: August 2002

Micro‐Raman spectra were recorded for two samples of polycrystalline La0.67Ca0.33MnO3, which were synthesized from oxides with oxygen isotopes 16O and 18O. Isotope Raman shifts were measured and compared with the theoretical prediction. In this way the oxygen‐related Raman modes were clearly identified. Temperature‐related blue Raman shifts for 16O (18O) vibration modes at 230 cm−1 (216 cm−1) were unexpectedly observed. These blue Raman shifts were compared with the blue shift due to lattice parameter variation as the temperature is lowered. The large blue Raman shift that occurs with decrease in temperature demonstrates that the Jahn–Teller distortion may play an important role. The appearance of new peaks at 440–480 and 410–450 cm−1 for 16O and 18O samples, respectively, as the temperature decreases to 140–100 K indicates a possible charge–orbit ordering transition. A continuous low‐wavenumber signal was observed which is superimposed on the broad phonon Raman lines. It was found that the scattering intensity of the low‐wavenumber signal is dramatically reduced as the temperature is lowered. The nature of this excitation is not clear. Copyright © 2001 John Wiley & Sons, Ltd.
Fourier transform Raman and surface‐enhanced Raman spectroscopy of some quinoline derivatives
Authors: Bolboaca M. , Kiefer W. , Popp J.
Published: August 2002

Fourier transform (FT) Raman and surface‐enhanced Raman spectroscopy (SERS) were applied to the vibrational characterization of isoquinoline and 4‐methylquinoline. The assignment of the vibrational modes was carried out on the basis of results obtained from density functional theory calculations. The comparison of SER spectra with the FT‐Raman spectra reveals remarkable changes attributed to the chemical interaction between the molecules and the silver substrate. The SER spectra of the adsorbed molecules depend strongly on the pH conditions. Variation in SER spectra with change of pH is attributed to a change in orientation of the absorbed isoquinoline molecules with respect to the silver surface and to a change in the chemical nature of the 4‐methylquinoline molecules. Copyright © 2002 John Wiley & Sons, Ltd.
Post‐harvest increase of indolyl glucosinolates in response to chopping and storage of Brassica vegetables
Authors: Verkerk Ruud , Dekker Matthijs , Jongen Wim M F
Published: August 2002

Brassica vegetables contain high amounts of glucosinolates, which contribute to the beneficial health effects of their consumption. Processing of such vegetables in domestic food preparation or industrial processing will influence levels of glucosinolates considerably and thus affect their health‐protective capacity. This study demonstrates the effects of chopping of raw Brassica vegetables on their glucosinolate composition. Limited breakdown of aliphatic glucosinolates in cabbage was found, whereas unexpected increased levels of indolyl glucosinolates were detected after chopping and storage of cabbage and broccoli under ambient conditions. In chopped white cabbage a 15‐fold increase of 4‐methoxy‐ and 1‐methoxy‐3‐indolylmethyl glucosinolates was noted after 48 h of storage. Chopping and storage of broccoli resulted in a strong reduction of most glucosinolates, except for 4‐hydroxy‐ and 4‐methoxy‐3‐indolylmethyl glucosinolates, which increased 3.5‐ and 2‐fold respectively. The myrosinase‐mediated hydrolysis of glucosinolates appears to be counteracted by a post‐harvest increase of some indolyl glucosinolates. In this paper we propose a mechanism of stress‐induced increase of glucosinolates, which plays an important role besides the well‐known breakdown mechanism.

© 2001 Society of Chemical Industry
Prognosis of T4 gastric carcinoma patients: An appraisal of aggressive surgical treatment
Authors: Dhar Dipok Kumar , Kubota Hirofumi , Tachibana Mitsuo , Kinugasa Shoichi , Masunaga Reiko , Shibakita Muneaki , Kohno Hitoshi , Nagasue Naofumi
Published: August 2002

Background and Objectives

Despite precipitous drop in the incidence of gastric carcinoma in Japan, it is still one of the leading causes of death associated with malignant disease. Once the contiguous organs are involved the prognosis becomes dismal. Prognostic factors governing the survival of patients with T4 gastric carcinoma remain unclear.

Methods

Between 1980 and 1998, 150 patients were treated for T4 gastric carcinoma. Results and prognostic factors were evaluated by univariate and multivariate analyses.

Results

With a 73% resectability, patients with tumor resection had a significantly (P < 0.0001) improved survival rate. Within an acceptable operative mortality (2.6‐), apparently curative cases had survival benefit (P < 0.0001) over noncurative cases. In the multivariate analysis, the death risk increased by 2.18 (relative risk) when splenectomy was spared from the operative procedure (P < 0.0071). Presence of esophageal invasion was the other independent prognostic factor in T4 gastric carcinoma patients (relative risk 2.11). Conventional prognostic factors along with the type of organs invaded by the carcinoma had no impact on prognosis.

Conclusions

Patients with T4 gastric carcinoma might be benefited from aggressive surgery with a curative intent. Whenever possible, splenectomy should be done along with invaded organ resection. J. Surg. Oncol. 2001;76:278–282. © 2001 Wiley‐Liss, Inc.
Complications and functional evaluation of 17 saddle prostheses for resection of periacetabular tumors*
Authors: Cottias Pascal , Jeanrot Cécile , Vinh Tho Son , Tomeno Bernard , Anract Philippe
Published: August 2002

Seventeen saddle prostheses were inserted between 1988 and 1997 after resection of periacetabular tumors. The tumors involved the zones II and III of Enneking classification in 13 patients, the zones I and II in 2 patients, and the zone II in 2 patients. The tumors included 11 chondrosarcomas, 3Ewing sarcomas, 2 giant cells tumors, and 1 metastasis of renal carcinoma. The tumoral resection was wide “en bloc” in 14 cases, marginal in 2 cases, and intratumoral in 1 case. The mean follow‐up period of the patients is 42 months ranging from 8 to 84 months. Local recurrences occured in five cases and metastases in four cases. Five patients died of tumoral disease and one of intercurrent disease. Complications were observed in 11 cases (65%) including nerve damages (3 cases), deep infections (3 cases), upward migrations of the saddle (4 cases), saddle dislocations (3 cases), sacroiliac subluxations (2 cases), and mechanical failures (2 cases). The modified Musculoskeletal Tumor Society Score (MSTS) and the Toronto Extremity Salvage Score (TESS) were used for functional analysis. Functional results were available for only nine patients of the series with a mean MSTS of 17 points ranging from 11 to 23 points and a mean TESS of 58 points ranging from 39 to 95 points. The saddle prosthesis provided in all cases of this series an early painfree weight‐bearing reconstruction with minimal limb shortening, but the functional results remained fair in most patients due to a limited range of motion and a poor abductor strength. J. Surg. Oncol. 2001;78:90–100. © 2001 Wiley‐Liss, Inc.
1,2‐Pentadiene decomposition
Authors: Herzler Juergen , Manion Jeffrey A. , Tsang Wing
Published: August 2002

1,2‐Pentadiene has been decomposed in single pulse shock tube experiments. There appear to be a large number of parallel decomposition and isomerization channels. The following rate expressions for isomerization in the temperature range 1100–1250 K and pressures between 200 and 300kPa have been obtainedk(1,2‐pentadiene → 1‐pentyne) = 1.0 × 1013exp(−32300 ± 900 K/T) s−1k(1,2‐pentadiene → cis/trans‐1,3‐pentadiene = 2.2 × 1014exp(−33900 ± 900 K/T) s−1k(1,2‐pentadiene → cyclopentene) = 1.8 × 1011exp(−26080 ± 900 K/T) s−1Overall, we estimate the 2σ uncertainty in the absolute rate constants to be about 30%. From detailed balance the rate expression for 1,3 to 1,2‐pentadiene isomerization has been found to bek(1,3‐pentadiene → 1,2‐pentadiene) = 1.2 × 1015exp(−42070 ± 900 K/T) s−1The significance of the 1,3 to 1,2 isomerization process as a bridge between the two‐carbon and three‐carbon species in high temperature hydrocarbon decomposition systems is discussed.

The decomposition processes involve bond breaking and retroene reactions. The rate expression for the latter has been found to bek(1,2‐pentadiene → propyne + ethylene) = 6.6 × 1012exp(−29240 ± 900 K/T) s−1The rate constants for fission of the C3C4and C4C5bonds appear to be close to each other. Our results indicate that the resonance energy of the 1,3‐butadiene‐2‐yl radical is smaller than that of allyl radical by an amount equal to the π bond conjugation energy of butadiene. © 2001 John Wiley & Sons, Inc.*

This article is a US Government work and, as such, is in the public domain in the United States of America.

Int J Chem Kinet 33: 755–767, 2001