bluuebunny/crossref_metadata_2025_split huggingface dataset:
MRI of carcinoid tumors: Spectrum of appearances in the gastrointestinal tract and liver
Authors: Bader Till R. , Semelka Richard C. , Chiu Vivian C.Y. , Armao Diane M. , Woosley John T. 
Published: August 2002

AbstractThe purpose of this study was to evaluate the spectrum of appearances of gastrointestinal carcinoid tumors at magnetic resonance imaging (MRI) and to elucidate patterns of appearances of carcinoid liver metastases on precontrast and postgadolinium images. The MR examinations of 29 patients (11 men, 18 women; age range, 33–87 years) with histologically confirmed gastrointestinal carcinoid tumors, representing our complete 9.5 years of experience with this entity, were retrospectively reviewed. Twelve patients had MR examinations prior to resection or biopsy of the primary tumor (preoperative group); 17 patients were imaged postsurgically (postoperative group). All MR studies were performed at 1.5 T and comprised T1‐weighted spoiled gradient echo (SGE), T2‐weighted fat‐suppressed turbo spin echo, HASTE, and serial postgadolinium T1‐weighted SGE sequences without and with fat suppression. Morphology, signal intensity, and contrast enhancement of primary tumors and of metastases to the mesentery, peritoneum, and liver were evaluated. Primary tumors were visualized in 8 of 12 patients and best demonstrated on postgadolinium T1‐weighted fat‐suppressed images. The appearance of primary tumors was a nodular mass originating from the bowel wall (4 of 12 patients) or regional uniform bowel wall thickening (4 of 12 patients) with moderate intense enhancement on postgadolinium images. In 4 of 12 patients the primary tumor was prospectively not seen. Mesenteric metastases, seen in eight patients, presented as nodular masses and were associated with mesenteric stranding in seven patients. A total of 156 liver metastases were evaluated in 16 patients. On precontrast T1‐ and T2‐weighted images, 117 metastases (75%) were hypointense and hyperintense, respectively. A total of 146 metastases (94%) were hypervascular, showing moderate intense enhancement during the hepatic arterial phase, and 9 metastases (6%) were hypovascular. Twenty‐three metastases (15%) were visible only on immediate postgadolinium images. MRI is able to demonstrate findings in carcinoid tumors, including the primary tumor, mesenteric metastases, and liver metastases. Liver metastases are commonly hypervascular and may be demonstrable only on immediate postgadolinium images. J. Magn. Reson. Imaging 2001;14:261–269. © 2001 Wiley‐Liss, Inc.
Application of magnetic resonance to animal models of cerebral ischemia
Authors: Hoehn Mathias , Nicolay Klaas , Franke Claudia , van der Sanden Boudewijn 
Published: August 2002

AbstractThe present review has been compiled to highlight the role of magnetic resonance imaging (MRI) and MR spectroscopy (MRS) for the investigation of cerebral ischemia in the animal experimental field of basic research. We have focused on stroke investigations analyzing the pathomechanisms of the disease evolution and on new advances in both nuclear MR (NMR) methodology or genetic engineering of transgenic animals for the study of complex molecular relationships and causes of the disease. Furthermore, we have tried to include metabolic and genetic aspects, as well as the application of functional imaging, for the investigation of the disturbance or restitution of functional brain activation under pathological conditions as relates to controlled animal experiments. J. Magn. Reson. Imaging 2001;14:491–509. © 2001 Wiley‐Liss, Inc.
MRI measurement of wall shear stress vectors in bifurcation models and comparison with CFD predictions
Authors: Köhler Uwe , Marshall Ian , Robertson Malcolm B. , Long Quan , Xu X. Yun , Hoskins Peter R. 
Published: August 2002

AbstractSteady fluid flow was studied in a simple bifurcation model and in a physiologically realistic model of the human carotid bifurcation. Wall shear stress (WSS) vectors were calculated from phase‐contrast (PC) magnetic resonance imaging (MRI) measurements of the velocity field. Velocity measurements in the inflow regions were also used as boundary conditions for computational fluid dynamics (CFD) calculations of WSS, which were compared with those derived from MRI alone. In regions of well‐behaved flow, MRI and CFD estimates of WSS were in good general agreement. In regions of disturbed flow, for example near the bifurcation, the quality of the MRI measurements was sufficient for reliable calculation of WSS vectors when a sensitive surface coil was used. The combination of MRI and CFD would seem to be a powerful technique for the investigation of flow phenomena. J. Magn. Reson. Imaging 2001;14:563–573. © 2001 Wiley‐Liss, Inc.
Sequence analysis of hepatitis C virus isolated from a fulminant hepatitis patient*
Authors: Kato Takanobu , Furusaka Akihiro , Miyamoto Michiko , Date Tomoko , Yasui Kotaro , Hiramoto Jun , Nagayama Kazuo , Tanaka Teruji , Wakita Takaji 
Published: August 2002

AbstractAlthough hepatitis C virus (HCV) is a major cause of non‐A non‐B hepatitis, its pathogenic role in fulminant hepatitis remains controversial. A 32‐year‐old man contracted hepatitis. Serum ALT concentration was reached to 6,970 IU/L, the lowest prothrombin time value was 16% and jaundice and stage II encephalopathy were developed. HCV RNA was detected in this patient by reverse transcription polymerase chain reaction in sera at the acute phase, and it was undetectable during the remission phase when anti‐HCV was found. The entire genome of infected HCV was recovered, cloned, and sequenced from this patient, and compared with the clones of six other chronic hepatitis patients. Phylogenetic analysis revealed a clustering around genotype 2a and a deviation from the other 2a chronic hepatitis strains. Calculating the genetic distance in each subgenomic region revealed that the 5′untranslated region (5′UTR), core, nonstructural (NS) 3, and NS5A were severely deviated. Of 20 clones of the hypervariable region (HVR), 17 showed an identical sequence with the others showing a difference of only one amino acid. HCV was isolated from a fulminant hepatitis patient and its entire genome was recovered; a clustering around genotype 2a was observed, but the sequence deviated especially in 5′UTR, core, NS3, and NS5A; and monoclonality of the HVR sequence was found not only in the fulminant hepatitis patient but in a certain percentage of chronic hepatitis patients. J. Med. Virol. 64:334–339, 2001. © 2001 Wiley‐Liss, Inc.
Detection of measles virus genome in lymphocytes from asymptomatic healthy children
Authors: Sonoda Satomi , Nakayama Tetsuo 
Published: August 2002

AbstractA total of 342 samples of peripheral blood mononuclear cells (PBMC) were obtained from 145 healthy individuals, which we examined for the presence of measles virus genome RNA by reverse transcription‐polymerase chain reaction (RT‐PCR), to identify whether asymptomatic infection of measles virus has occurred in healthy children. Measles virus genome was detected in 11 (23.4%) of 47 nonimmunized individuals; all positives for RT‐PCR were infants who experienced measles exposure. No genome was detected in those without measles exposure. In 83 individuals immunized with measles vaccine, the vaccine strain genome was detected in 10 (71.4%) of 14 recipients whose PBMC were obtained within 2 months of vaccination. Measles wild‐type genome was detected in 36 (46.2%) of 78 individuals, 40 (25.2%) of 159 samples, who had been immunized more than 2 months before. The wild‐type measles genome was also detected in 6 (46.2%) of 13 individuals who had been infected with measles in the distant past. The measles PCR‐positive rate was not related to the period since immunization or natural infection. Sequence analysis of PCR products demonstrated they were all in the same cluster of D5 lineage, which was the circulating strain during the study period. We obtained 13 samples of nasopharyngeal secretion (NPS) simultaneously from individuals whose PBMC were positive for measles PCR but did not detect virus genome. Measles genome was, however, detected from NPS in cases of acute infection. We conclude that asymptomatic measles infection is common but would rarely become a source of transmission because of negative PCR in NPS. J. Med. Virol. 65:381–387, 2001. © 2001 Wiley‐Liss, Inc.
Molecular epidemiology of molluscum contagiosum virus and analysis of the host‐serum antibody response in Spanish HIV‐negative patients
Authors: Agromayor Monica , Ortiz Pablo , Lopez‐Estebaranz Jose L. , Gonzalez‐Nicolas Josefa , Esteban Mariano , Martin‐Gallardo Antonia 
Published: August 2002

AbstractMolluscum contagiosum virus (MCV) lesions from Spanish human immunodeficiency virus (HIV)‐negative patients were clinically examined and analyzed for virus detection and typing. In a study of 147 patients, 97 (66%) were children under 10 years, of whom 49% had atopic dermatitis. MCV lesions were morphologically indistinguishable among the different age groups, but atopic patients presented larger lesions compared with patients without the disorder. In adults, lesions were observed mainly on the genitals. MCVI was the predominant subtype. The deduced MCVI/MCVII ratio (146:1) was much higher than that found in other geographical areas. Protein preparations of the virus‐induced lesions were immunoblotted with sera from 25 MCVI patients. The host‐serum antibody response was weak and variable, although no significant differences were found between atopic and nonatopic patients. Three immunoreactive proteins of 74/80, 60, and 35 kDa were detected in almost all the analyzed sera. The 35 and 74/80‐kDa proteins were virus specific, whereas the 60‐kDa protein band was composed of a mix of human keratins. Immunoblotting of MCV lesions and vaccinia virus‐infected cell extracts with either MCV patient serum or a rabbit antiserum against vaccinia virus showed no cross‐reactivity of these two human poxviruses at the antigenic level. J. Med. Virol. 66:151–158, 2002. © 2002 Wiley‐Liss, Inc.
Clinical and immunological efficacy of intradermal vaccine plus lamivudine with or without interleukin‐2 in patients with chronic hepatitis B
Authors: Dahmen Anja , Herzog‐Hauff Sabine , Böcher Wulf O. , Galle Peter R. , Löhr Hanns F. 
Published: August 2002

AbstractTo evaluate therapeutic immunostimulation nine chronic hepatitis B patients received six monthly intradermal vaccinations with HBsAg in combination with daily lamivudine. Another five patients received six doses of the vaccine and daily lamivudine together with daily Interleukin‐2 (IL‐2) s.c. within 3 months in an open‐labeled trial. Clinical efficacy was assessed by alanine transaminase levels and HBV serology. The induction of specific T and B cell responses was analyzed serially by 3H‐thymidine uptake, ELISA and ELISPOT assays. After the therapy was stopped, seven of nine vaccine/lamivudine and two of five vaccine/lamivudine/IL‐2 recipients did not have detectable HBV DNA. Four complete responders cleared the virus and had normalized ALT levels, however, one of these patients showed transient disease reactivation followed by spontaneous viral clearance and normal ALT five months later. Low frequencies of anti‐HBs producing B cells and HBV specific T helper cells secreting predominantly interferon‐γ were induced by i.d. vaccine therapy. The ELISPOT technique demonstrated transient induction of HBV peptide specific cytotoxic T cells in seven HLA‐A2 positive chronic HBV carriers. The preliminary data from this study demonstrate that the HBV surface antigen vaccine in combination with antiviral or immunomodulating drugs induced antiviral immune responses and consequently viral elimination may be achieved in patients with unfavorable prognosis. J. Med. Virol. 66:452–460, 2002. © 2002 Wiley‐Liss, Inc.
Sequence diversity of human caliciviruses recovered from children with diarrhea in mendoza, Argentina, 1995–1998
Authors: Martínez Norma , Espul Carlos , Cuello Hector , Zhong Weiming , Jiang Xi , Matson David O. 
Published: August 2002

AbstractHuman caliciviruses were detected by EIA and/or RT‐PCR in stool specimens from children with diarrhea treated at out‐ or in‐patient facilities between 1995 and 1998 in Mendoza, Argentina. Mexico virus–like strains detected by primers NV36/51 were transiently prevalent in 1995/1996. Significantly more human caliciviruses were detected when primers were designed from contemporaneously circulating strains. Nucleotide sequences of a highly conserved region in the RNA polymerase gene of 10 selected human caliciviruses were determined. Eight strains were Norwalk‐like viruses and two strains were Sapporo‐like viruses. Seven of the eight Norwalk‐like viruses also were positive by the recombinant Mexico virus antigen EIA. The seven Mexico virus EIA‐positive strains revealed two patterns in the RNA polymerase sequences: two strains were closest to Mexico virus and the other five strains were closest to Lordsdale virus. One of the five “Lordsdale” viruses was found to be a naturally occurring recombinant between the Mexico virus and Lordsdale human calicivirus genetic clusters [Jiang et al., (1999b) Archives of Virology 144:2377–2387]. The Mexico virus EIA‐negative strain had 73–77% nucleotide identity with the closest related Norwalk‐like viruses, indicating it might belong to a new genetic cluster of the Norwalk‐like virus genus. The two Sapporo‐like viruses were distinct genetically; one belonged to the Houston/90 or Parkville cluster and the other to a new cluster. Some strains appeared to have short periods of prevalence and locally adapted primer pairs significantly increased detection rates. The finding of high diversity of circulating strains, including recombinant strains and strains with previously unrecognized genetic identities, highlights a need for studies of human caliciviruses in these children and other populations. J. Med. Virol. 67:289–298, 2002. © 2002 Wiley‐Liss, Inc.
Aluminum, NO, and nerve growth factor neurotoxicity in cholinergic neurons
Authors: Szutowicz Andrzej 
Published: August 2002

AbstractSeveral neurotoxic compounds, including Al, NO, and β‐amyloid may contribute to the impairment or loss of brain cholinergic neurons in the course of various neurodegenerative diseases. Genotype and phenotypic modifications of cholinergic neurons may determine their variable functional competency and susceptibility to reported neurotoxic insults. Hybrid, immortalized SN56 cholinergic cells from mouse septum may serve as a model for in vitro cholinotoxicity studies. Differentiation by various combinations of cAMP, retinoic acid, and nerve growth factor may provide cells of different morphologic maturity as well as activities of acetylcholine and acetyl‐CoA metabolism. In general, differentiated cells appear to be more susceptible to neurotoxic signals than the non‐differentiated ones, as evidenced by loss of sprouting and connectivity, decreases in choline acetyltransferase and pyruvate dehydrogenase activities, disturbances in acetyl‐CoA compartmentation and metabolism, insufficient or excessive acetylcholine release, as well as increased expression of apoptosis markers. Each neurotoxin impaired both acetylcholine and acetyl‐CoA metabolism of these cells. Activation of p75 or trkA receptors made either acetyl‐CoA or cholinergic metabolism more susceptible to neurotoxic influences, respectively. Neurotoxins aggravated detrimental effects of each other, particularly in differentiated cells. Thus brain cholinergic neurons might display a differential susceptibility to Al and other neurotoxins depending on their genotype or phenotype‐dependent variability of the cholinergic and acetyl‐CoA metabolism. © 2001 Wiley‐Liss, Inc.
Osteopontin: A novel axon‐regulated Schwann cell gene
Authors: Jander Sebastian , Bussini Simona , Neuen‐Jacob Eva , Bosse Frank , Menge Til , Müller Hans‐Werner , Stoll Guido 
Published: August 2002

AbstractOsteopontin (OPN) is a RGD‐containing glycoprotein with cytokine‐like, chemotactic, and pro‐adhesive properties. During wound healing, OPN is abundantly expressed by infiltrating macrophages and has been implicated in posttraumatic tissue repair. To delineate a role in the regenerative response to axotomy we examined the expression of OPN in Wallerian degeneration of the sciatic nerve in rats. Unexpectedly, we found high constitutive expression of OPN by myelinating Schwann cells (SCs) in uninjured control nerves. OPN mRNA expression was confirmed in primary cultures of rat SCs. Upon axotomy, SC‐expressed OPN in the degenerating distal nerve stump transiently increased during the first days after injury, but was continuously downregulated thereafter, reaching its minimum at Day 14. Macrophages invading axotomized nerves were OPN‐negative. During late stages after axotomy, SC‐OPN was reexpressed in regenerating but not permanently transected nerves. We also found OPN expression by myelinating SCs in human sural nerves with a dramatic reduction in severe axonal polyneuropathies. Taken together, our study identifies OPN as a novel Schwann cell gene regulated by axon‐derived signals. The lack of OPN induction in infiltrating macrophages indicates fundamental differences in tissue repair between axonal injury in the peripheral nervous system and structural lesions in other organ systems. © 2002 Wiley‐Liss, Inc.
Loss of stimulatory effect of guanosine triphosphate on [35S]GTPγS binding correlates with Alzheimer's disease neurofibrillary pathology in entorhinal cortex and CA1 hippocampal subfield
Authors: García‐Jiménez A. , Cowburn R.F. , Ohm T.G. , Lasn H. , Winblad B. , Bogdanovic N. , Fastbom J. 
Published: August 2002

AbstractHeterotrimeric guanosine triphosphate (GTP)‐binding proteins (G‐proteins) couple many different cell surface receptor types to intracellular effector mechanisms. Uncoupling between receptors and G‐proteins and between G‐proteins and adenylyl cyclase (AC) and phospholipase C (PLC) has been described for Alzheimer's disease (AD) brain. However, there is little information on whether altered G‐protein signaling in AD is just an end‐stage phenomenon or is important for the progression of disease pathology. Here we used [35S]GTPγS autoradiography to study G‐protein distribution in sections of entorhinal cortex and hippocampus from 23 cases staged for neurofibrillary changes and amyloid deposits according to Braak and Braak (Acta Neuropathol. [1991] 82:239–259). We also studied the effects of GTP, which has been found to increase [35S]GTPγS binding in an Mg2+‐dependent manner. Results show that the ability of GTP (3 μM) to stimulate [35S]GTPγS binding declined significantly with staging for neurofibrillary changes in the entorhinal cortex (P < 0.05, ANOVA) and CA1 subfield of the hippocampus (P < 0.05, ANOVA). No significant changes were seen for [35S]GTPγS binding in the absence of GTP. Our results suggest a decrease in G‐protein GTP hydrolysis, which correlates with the progression of AD neurofibrillary changes, in the regions most affected by this pathology. These alterations appear to occur prior to stages corresponding to clinical disease and could lead to an impaired regulation of several signaling systems in AD brain. © 2002 Wiley‐Liss, Inc.
Neuroprotective actions of selegiline
Authors: Ebadi M. , Sharma S. , Shavali S. , El Refaey H. 
Published: August 2002

AbstractSelegiline, a selective inhibitor of monoamine oxidase‐B (MAO‐B), was one of the first adjunct therapies in clinical neurology. A retrospective analysis of data from patients with Parkinson's disease found a significant increase in survival in those treated with selegiline plus L‐dopa compared with L‐dopa alone. The mechanism of action of selegiline is complex and cannot be explained solely by its MAO‐B inhibitory action. Pretreatment with selegiline can protect neurons against a variety of neurotoxins, such as 1‐methyl‐4‐phenyl‐1,2,3,6 tetrahydropyridine (MPTP), 6‐hydroxydopamine, N‐(2‐chloroethyl)‐N‐ethyl‐2‐bromobenzylamine (DSP‐4), methyl‐β‐acetoxyethyl‐2‐chloroethylamine (AF64A), and 5,6‐dihydroxyserotonin, which damage dopaminergic, adrenergic, cholinergic, and sertoninergic neurons, respectively. Selegiline produces an amphetamine‐like effect, enhances the release of dopamine, and blocks the reuptake of dopamine. It stimulates gene expression of L‐aromatic amino acid decarboxylase, increases striatal phenylethylamine levels, and activates dopamine receptors. Selegiline reduces the production of oxidative radicals, up‐regulates superoxide dismutase and catalase, and suppresses nonenzymatic and iron‐catalyzed autooxidation of dopamine. Selegiline compensates for loss of target‐derived trophic support, delays apoptosis in serum‐deprived cells, and blocks apoptosis‐related fall in the mitochondrial membrane potential. Most of the aforementioned properties occur independently of selegiline's efficacy to inhibit MAO‐B. © 2002 Wiley‐Liss, Inc.
Long‐term fate of human telencephalic progenitor cells grafted into the adult mouse brain: Effects of previous amplification in vitro
Authors: Buchet Delphine , Buc‐Caron Marie‐Hélène , Sabaté Olivier , Lachapelle François , Mallet Jacques 
Published: August 2002

AbstractWe assessed the developmental potential of human telencephalic progenitor cells, with and without previous amplification in vitro, following grafting into the nonlesioned adult mouse CNS. Cell suspensions, shown to contain neuroepithelium‐like and neuroblast‐like cells, were injected into the subventricular zone (SVZ) and the striatum. These two regions were selected for comparative studies because one, the SVZ, is mitotically active, whereas the other, the striatum, is mitotically inactive. In situ hybridization with a human‐specific Alu probe showed that the cells survived for up to 30 weeks in both targets and migrated away from the injection site. Fresh cells continued to proliferate and gave rise to very extended grafts before differentiating into neurons and glia. We further show that, when grown in vitro prior to grafting, human cells acquired new properties: Their proliferation was very limited, and they differentiated more rapidly. This study therefore provides new information about the use of these cells, which are a potential tool for both cellular and gene therapy. © 2002 Wiley‐Liss, Inc.
Differential enhancement of dialysate serotonin levels in distinct brain regions of the awake rat by modafinil: Possible relevance for wakefulness and depression
Authors: Ferraro Luca , Fuxe Kjell , Tanganelli Sergio , Tomasini Maria Cristina , Rambert Francis A. , Antonelli Tiziana 
Published: August 2002

AbstractThe present in vivo microdialysis study evaluates the possible existence of a differential regulation of serotonergic transmission by the antinarcoleptic drug modafinil [(diphenyl‐methyl)‐sulfinyl‐2‐acetamide; Modiodal] among various brain regions of the awake rat. The results show that, in the cerebral cortex, the central amygdala, and the dorsal raphe nucleus, modafinil in the dose range of 10–100 mg/kg i.p. dose‐dependently increases dialysate serotonin (5‐HT) levels. In other brain areas, such as the medial preoptic area and the posterior hypothalamus, the modafinil‐induced increase in dialysate 5‐HT levels is observed only at tenfold higher doses (100 mg/kg), 10–30 mg/kg being ineffective. Together these data suggest that, in the frontal cortex, the amygdala, and the dorsal raphe, modafinil is more potent in enhancing extracellular 5‐HT levels and presumably 5‐HT transmission than in the medial preoptic area and the posterior hypothalamus. In view of the role of ascending 5‐HT pathways in arousal and depression, it seems likely that the antinarcoleptic drug modafinil may also have an antidepressant potential in addition to its wakefulness‐promoting action, both actions involving enhancement of 5‐HT neurotransmission. © 2002 Wiley‐Liss, Inc.