bluuebunny/crossref_metadata_2025_split huggingface dataset:
YMDD mutants in patients with chronic hepatitis B before treatment are not selected by lamivudine
Authors: Matsuda Marie , Suzuki Fumitaka , Suzuki Yoshiyuki , Tsubota Akihito , Akuta Norio , Hosaka Tetsuya , Someya Takashi , Kobayashi Masahiro , Saitoh Satoshi , Arase Yasuji , Satoh Junko , Kobayashi Mariko , Ikeda Kenji , Miyakawa Yuzo , Kumada Hiromitsu 
Published: August 2004

AbstractHepatitis B virus (HBV) mutants with mutations in the YMDD motif of viral DNA polymerase/reverse transcriptase are described in patients infected with HBV who have not received lamivudine therapy, but their pathogenetic potential is not clear. These mutants were detected by the polymerase chain reaction with peptide nucleic acid clamping in pretreatment sera from two patients who later received lamivudine. One patient developed acute exacerbation with hepatic encephalopathy and received lamivudine along with plasma exchange, which were effective on his illness. YIDD mutants were detected in all three pretreatment sera and both posttreatment sera from him. HBV DNA clones from pretreatment and posttreatment sera, however, did not have the same amino acid sequence. In the other patient who developed severe breakthrough hepatitis after receiving lamivudine, YIDD mutants were detected in two pretreatment and two posttreatment sera. When amino acid sequences of HBV DNA clones with the YIDD mutation were compared before and after he received lamivudine, however, they were not in accord. Hence, YIDD mutants in both patients with chronic hepatitis B before treatment were not selected by lamivudine after they had been placed on it. Numerous amino acid conversions were detected in HBV DNA clones with YIDD mutations, and some of them created stop codons in the overlapping S gene sequence. In Conclusion, HBV mutants with mutations in the YMDD motif in patients before treatment would not be selected by lamivudine or induce breakthrough hepatitis, and some of these would not be replication‐competent due to stop codons in the S gene. J. Med. Virol. 74:361–366, 2004. © 2004 Wiley‐Liss, Inc.
Glycosphingolipid composition of primary cultured human brain microvascular endothelial cells
Authors: Kanda Takashi , Ariga Toshio , Kubodera Hisako , Jin Hong Lian , Owada Kiyoshi , Kasama Takeshi , Yamawaki Masanaga , Mizusawa Hidehiro 
Published: August 2004

AbstractGlycosphingolipid (GSL) antigens have been considered to be involved in the pathogenesis of autoimmune neurologic disorders including multiple sclerosis. To establish the GSL pattern specific for endothelial cells forming blood–brain barrier (BBB), we established a method to yield sufficient quantities of highly purified human brain microvascular endothelial cells (HBMECs) and compared their GSL composition to that of human umbilical cord vein endothelial cells (HUVECs), as the representative of endothelial cells not forming BBB. The major gangliosides were GM3 and sialyl paragloboside (LM1), and the major neutral GSLs were lactosylceramide (LacCer), globotriaosylceramide (Gb3), and globoside (Gb4). Trace amounts of GM1, GD1a, GD1b, GT1b, and sulfoglucuronosyl paragloboside (SGPG) could be detected by the high performance thin layer chromatography‐overlay method. SGPG was detected only at a nonconfluent state in an amount almost 1/30 that of in nonconfluent HUVECs. Conversely, GM3 and LM1 increased significantly after confluency. The amount of Gb3 in HBMECs was almost as twice that in HUVECs. The significance of these differences in GSL content between HBMECs and HUVECs and between confluent and nonconfluent states is obscure. It might be related, however, to the defense mechanism at the BBB and to the susceptibility of the central nervous system in some disorders that target cell surface GSL, such as hemolytic uremic syndrome. © 2004 Wiley‐Liss, Inc.
Characterization of retinoic acid neuromodulation in the carp retina
Authors: Dirks Petra , Tieding Silke , Schneider Ilka , Mey Jörg , Weiler Reto 
Published: August 2004

AbstractVisual sensation in vertebrates starts with the isomerization of 11‐cis retinaldehyde into all‐trans retinaldehyde. Aldehyde dehydrogenases, present in the pigment epithelium and some retinal cells, convert all‐trans retinaldehyde into all‐trans retinoic acid (at‐RA). Evidence in the retina and the hippocampus has accumulated, showing that at‐RA, besides being a morphogenetic factor, also acts as a neuromodulator. In mature retina, at‐RA affects visual processing by acting on gap junctional conductances and the synaptic transfer between photoreceptors and horizontal cells. We present evidence supporting a neuromodulatory role of at‐RA in the carp retina. High performance liquid chromatography (HPLC) measurements and an RA bioassay indicate a light dependency of at‐RA formation, which can explain the observed effects of at‐RA on spinule formation at horizontal cell dendrites in this retina. Furthermore, inhibiting endogenous metabolism and catabolism of at‐RA affects formation and persistence of spinules in a way, supporting a direct involvement of at‐RA in this light‐dependent mechanism of synaptic plasticity. The action of at‐RA, however, seems independent of the dopaminergic system, known for its light‐signaling role in the retina, because at‐RA effects on spinule formation persisted in retina depleted of dopaminergic neurons or in the presence of haloperidol. Together, these data indicate that at‐RA acts effectively as a direct neuromodulator in carp retina, transmitting information about ambient light conditions to the neuronal retina. © 2004 Wiley‐Liss, Inc.
Apotransferrin induces cAMP/CREB pathway and cell cycle exit in immature oligodendroglial cells
Authors: Garcia C. , Paez P. , Davio C. , Soto E.F. , Pasquini J.M. 
Published: August 2004

AbstractWe have demonstrated previously that a single intracranial injection of apotransferrin (aTf) in neonatal rats increases myelination and accelerates differentiation of oligodendroglial cells (OLGc). In addition, we have shown through in vitro experiments that OLGc isolated from 4‐day‐old rats (OLGc‐4) treated with aTf were more differentiated than were controls although aTf had no effect upon OLGc isolated from 10‐day‐old animals (OLGc‐10). In the present work, we analyzed the role of second messengers in the effect of aTf upon the maturation of OLGc at different stages of development. We isolated OLGc‐4 and OLGc‐10 from rat brain using a Percoll density gradient and briefly treated the cells with a pulse of aTf or kept them in culture during 2 days in the presence or absence of aTf. In OLGc‐4, after a short pulse of aTf, there was an increase in the levels of cyclic AMP (cAMP), in the phosphorylation of cAMP response element‐binding protein (CREB) and in the DNA‐binding capacity of cAMP‐responsive transcription factors. Treatment of OLGc‐4 with aTf diminished bromodeoxyuridine (BrdU) incorporation and changed levels of p27 and cyclin D1. This glycoprotein seemed to act on OLGc through the cAMP pathway only at early stages of development and on a certain sensitive cell population, accelerating their differentiation, probably as a consequence of premature withdrawal from the cell cycle. © 2004 Wiley‐Liss, Inc.
Environmental change and cultural response between 8000 and 4000 cal. yr BP in the western Loess Plateau, northwest China
Authors: An ChengBang , Feng Zhaodong , Tang Lingyu 
Published: August 2004

AbstractTwo ancient swamps in the western Loess Plateau, northwest China record the climate history between 8000 and 4000 cal. yr BP. Grain size, CaCO3, organic matter, mollusc fauna and pollen assemblages show that climate was wet between 8300 and 7400 cal. yr BP, distinctly humid and warm between 7400 and 6700 cal. yr BP, semi‐humid from 6700 to 6300 cal. yr BP, and semi‐arid between 6300 and 4000 cal. yr BP. The temporal and spatial distribution of archaeological sites shows that the prosperity of the neolithic cultures in the western part of the Chinese Loess Plateau did not appear until the climate changed to semi‐arid, implying that the semi‐arid climate was more favourable than wet and humid climate to neolithic peoples, whose subsistence was based on cereals adapted to arid environments. Copyright © 2004 John Wiley & Sons, Ltd.
The Upper Pleistocene to Holocene sediments on the Mediterranean island of Lampedusa (Italy)
Authors: Giraudi C. 
Published: August 2004

AbstractThe island of Lampedusa lies on the northern edge of the African continental shelf, but during some Quaternary marine lowstands it was joined to the African continent. The study and dating of the aeolian, alluvial, detrital sediments, calcareous crusts and speleothems have established that the climatic–environmental variations recorded on the island can be related chronologically to those known for northern Libya, Tunisia and the Italian peninsula. During the Last Glacial Maximum, phases of Saharan dust accumulation on Lampedusa occurred, and were coeval with dust accumulation in crater lakes and on high mountains in central‐southern Italy, and with phases of glacial advance in the Apennines and in the Alps. During the late Holocene, accumulation of Saharan dust on Lampedusa occurred but there was little accumulation of dust on the northern side of the Mediterranean Sea. With the new data from Lampedusa, it is possible to envisage two different scenarios of atmospheric circulation relating to the Last Glacial Maximum and to the late Holocene. During the Last Glacial Maximum, southerly atmospheric circulation brought rainfall to the southern slopes of the Alps and to the Apennines. During the late Holocene, a prevalent westerly atmospheric circulation became established in the northern Mediterranean. Copyright © 2004 John Wiley & Sons, Ltd.
Elm bark beetle in Holocene peat deposits and the northwest European elm decline
Authors: Clark Sarah H. E. , Edwards Kevin J. 
Published: August 2004

AbstractThe elm decline of 5000 14C yr ago has been the most widely discussed phenomenon in post‐glacial vegetation history. This pan‐European reduction of elm populations, echoed in the decimation of elmwoods in Europe during the twentieth century, has attracted a series of interrelated hypotheses involving climate change, human activity, disease and soil deterioration. The elm bark beetle (Scolytus scolytus L.) is an essential component of disease explanations. We present evidence for the presence of the beetle over a prolonged period (ca. 7950–4910 yr BP [8800–5660 cal. yr BP]) from a lowland raised mire deposit in northeast Scotland, with its final appearance at this site, and the first and only appearance in another mire of a single scolytid find, around the time of the elm decline. The subfossil S. scolytus finds are not only the first from Scotland, but they also represent the most comprehensive sequence of finds anywhere. Copyright © 2004 John Wiley & Sons, Ltd.
Depositional and post‐depositional history of warm stage deposits at Knocknacran, Co. Monaghan, Ireland: implications for preservation of Irish last interglacial deposits
Authors: Vaughan A. P. M. , Dowling L. A. , Mitchell F. J. G. , Lauritzen S.‐E. , McCabe A. M. , Coxon P. 
Published: August 2004

AbstractOrganic‐rich deposits, uncovered during overburden removal from mantled gypsum karst at Knocknacran opencast gypsum mine, Co. Monaghan, are the best candidate to date for a last interglacial record in Ireland. The two till and organic‐rich deposits (preserved at different quarry elevations) were emplaced on to a Tertiary dolerite surface during high‐energy flood events and subsequently folded and faulted by movement towards sinkholes in underlying gypsum. Uranium–thorium disequilibrium dating suggests that the organic‐rich deposits in the upper section were hydrologically isolated at ca. 41 ka and those in the lower section at ca. 86 ka. Interpretation of the pollen content, although tentative because of the depositional and post‐depositional history of the material, suggests that the organic material originated in a warm stage possibly warmer than the post‐Eemian interstadials. The unusual setting of preservation may indicate that in situ, last interglacial deposits have generally been removed by erosion in Ireland. Copyright © 2004 John Wiley & Sons, Ltd.
The Pleistocene Cape Kidnappers section in New Zealand: orbitally forced controls on active margin sedimentation?
Authors: Proust Jean‐Noël , Chanier Frank 
Published: August 2004

AbstractHigh sedimentation rates in Pleistocene active margin basins can provide a very detailed record of tectonic and climatic controls on sediment preservation. A 500 m thick, Pleistocene rock section exposed in northeastern North Island of New Zealand (Kidnappers Group), provides the opportunity to discuss these controls. The section is composed of conglomerate, sandstones, siltstones and minor shales, interbedded with tephra layers. The sediments were deposited in alluvial to shallow marine environments and preserved in stacks of depositional units decimetres to hundreds of metres thick as a result of base‐level changes through time. The correlation of base‐level changes in the section with the deep sea oxygen isotope stratigraphy shows that the sequences at 10 m and 80 m scales can correlate, respectively, to the 20 and 100 kyr changes in eustatic sea‐level, but that the 80‐m‐thick sequences correlate also to changes in tectonic uplift rates. A major change in the stratigraphical architecture occurs at the Mid‐Pleistocene Transition (MPT) when the 40 kyr ice volume variations shifted to a dominant 100 kyr variation. This change includes an increase in the amplitude of the shifts in depositional environments and an overall simplification of the stacking pattern of the depositional units through the MPT. This study illustrates that active margin basins can record orbitally forced sedimentary cycles and points to a possible leading influence of eustasy on the pattern of sediment preservation in tectonically active areas. Copyright © 2004 John Wiley & Sons, Ltd.
Heparanase expression in human colorectal cancer and its relationship to tumor angiogenesis, hematogenous metastasis, and prognosis
Authors: Sato Tomohiro , Yamaguchi Akio , Goi Takanori , Hirono Yasuo , Takeuchi Kazuo , Katayama Kanji , Matsukawa Shigeru 
Published: August 2004

AbstractBackgroundHeparanase is considered to play an important role in tumor invasion and hematogenous metastasis. The aim of this study was to determine the expression of heparanase in colorectal cancer to evaluate its prognostic value.MethodsWe analyzed heparanase mRNA derived from 130 colorectal cancer patients by reverse transcription polymerase chain reaction (PCR), compared its expression with clinicopathologic factors, and performed statistical analysis. To investigate the relationship between heparanase expression and tumor angiogenesis, 81 primary colorectal tumors were immunostained by use of a monoclonal anti‐CD34 antibody.ResultsThirty three of 130 cancer tissues overexpressed heparanase. There were significant correlations between heparanase expression and serosal invasion, venous invasion, and liver metastasis. Multivariate analyzes revealed that heparanase mRNA overexpression was a significant independent risk factor for hematogenous metastasis in colorectal cancer. Among 104 patients who underwent curative resection, heparanase expression correlated with a high recurrence. The 5‐year survival rate was 84.6% for patients with heparanase negative tumors, and 47.7% for those with heparanase overexpression; these differences between two groups of patients were significant. In multivariate analysis using the Cox regression model, heparanese expression emerged as an independent prognostic indicator. Moreover, the tumor angiogenesis of heparanase‐positive tumors determined with a monoclonal anti‐CD34 antibody was significantly higher than that of heparanase‐negative tumors.ConclusionsThese results indicated that Heparanase expression may be an important role in invasion and hematogenous metastasis, and may be a biologic marker of prognostic significance in colorectal cancer patients. J. Surg. Oncol. 2004;87:174–181. © 2004 Wiley‐Liss, Inc.
Identification of a single nucleotide polymorphism in the MMP‐1 promoter in chondrosarcoma
Authors: Dickey Ian D. , Scully Sean P. 
Published: August 2004

AbstractMatrix metalloproteinases (MMPs) are a group of at least 26 enzymes that facilitate cellular invasion via the degradation of the extracellular matrix. Specifically, the ability to degrade collagen types III and I is important in tumor invasion and metastasis. Over expression of the MMP‐1 gene has been shown to correlate with poorer outcome in GI tract and gynecological tumors. This level of expression of this gene has been shown to be significantly increased by the presence of a single nucleotide polymorphism in the MMP‐1 promoter sequence as a result of the creation of an ETS binding site. This SNP results from the addition of a single guanine base at −1,607 bp 24. Two chondrosarcoma cell lines and a series of 10 resected chondrosarcoma specimens underwent DNA extraction, purification, polymerase chain reaction, and sequencing. The presence of the single nucleotide polymorphism at −1,607 bp was confirmed within the promoter region for MMP‐1 in human chondrosarcoma. Because all three genotypes were found in the clinical samples, the SNP may indeed provide a mechanistic explanation for a more aggressive biologic behavior locally and distally for a subset of chondrosarcomas. J. Surg. Oncol. 2004;87:130–133. © 2004 Wiley‐Liss, Inc.
Survival of patients with untreated rectal cancer
Authors: Melissa Solum A. , H. Riffenburgh Robert , A.S. Johnstone Peter 
Published: August 2004

AbstractBackground and ObjectivesUntreated rectal cancer is uncommon given modern surgical techniques and chemoradiotherapy. However, neglected cancer may still occur in patients with limited access to medical care or who refuse conventional interventions. Outcome data on such patients is scarce, though valuable in educating patients on their prognosis or to compare with present therapeutic options.MethodsTo identify such data, a review was made of archival literature documenting outcomes in patients with untreated rectal cancer. A review of the Index Medicus and its predecessor volumes and an extensive MEDLINE search led to nine articles that contained relevant age at presentation data of patients with rectal cancer. Six articles also included patient survival data for untreated rectal cancer. Actuarial analysis of the data through 5 years post‐diagnosis was completed.ResultsSymptoms most often presented in the fifth and sixth decades. Median survival of the 1326 patients fell within the second year after presentation of symptoms. Five‐year actuarial survival for these patients was 4.4%. When the data published prior to 1925 were analyzed separately from that published post‐1925, two survival patterns emerged. Median survival of pre‐1925 patients fell within the second year after presentation of symptoms (at 21.5 months by curve fitting) and of post‐1925 patients fell within the first year (10.2 months).ConclusionsClearly, advances in antibiotics, surgery, chemoradiotherapy, and supportive care have contributed to increased survival for patients with treated rectal cancer. Recognizing the hazards of generalizing too extremely from the data, they reveal that relatively long survival for patients with untreated lesions is possible. J. Surg. Oncol. 2004;87:157–161. © 2004 Wiley‐Liss, Inc.
Comparison of methylation‐specific polymerase chain reaction (MSP) with reverse transcriptase‐polymerase chain reaction (RT‐PCR) in peripheral blood of gastric cancer patients
Authors: Koike Hiroshi , Ichikawa Daisuke , Ikoma Hisashi , Otsuji Eigo , Kitamura Kazuya , Yamagishi Hisakazu 
Published: August 2004

AbstractBackground and ObjectivesTo achieve a complete cure in gastric cancer, primary and recurrent tumors must be detected at an early stage. This study was designed to compare carcinoembryonic antigen (CEA)‐specific reverse transcriptase‐polymerase chain reaction (RT‐PCR) and methylation‐specific polymerase chain reaction (MSP) for p16, E‐cadherin, and retinoic acid receptor beta (RARβ) genes using blood samples from gastric cancer patients.MethodsPreoperative blood samples obtained from 41 patients with gastric cancer, including 9 with early‐stage disease, and were subjected to RT‐PCR and MSP assays.ResultsTen of 41 (24%) patients exhibited a CEA‐specific signal by RT‐PCR. Positive rates were 11, 13, 50, and 50% in stages I, II, III, and IV, respectively. A significant association was found between RT‐PCR results and stage (P< 0.01). The MSP assay detected hypermethylation of p16 in 9 patients (22%), E‐cadherin in 9 patients (22%), and RARβ in 6 patients (15%). Altogether, 18 patients (44%) showed hypermethylation. The positive rates were 37, 50, 40, and 75% in stages I, II, III, and IV, respectively. A significant association was found between aberrant methylation and venous invasion (P< 0.05). Neither the CEA‐specific signal nor hypermethylation was detected in serum from control volunteers.ConclusionsThe detection rate of MSP was higher than that of RT‐PCR in gastric cancer. Both assays can serve as markers that allow selection of those cases requiring more intensive screening and aggressive postoperative treatment. J. Surg. Oncol. 2004;87:182–186. © 2004 Wiley‐Liss, Inc.
Utility of CEA and CA 19‐9 tumor markers in diagnosis and prognostic assessment of mucinous epithelial cancers of the appendix
Authors: Pablo Carmignani C. , Hampton Regina , E. Sugarbaker Christina , Chang David , H. Sugarbaker Paul 
Published: August 2004

AbstractBackground and ObjectivesTumor markers are a clinical tool frequently used in oncology in association with other clinical and radiologic information. For gastrointestinal cancer, carcinoembryonic antigen (CEA) and carbohydrate antigen 19‐9 (CA 19‐9) tumor markers have found selected clinical application. The use of these tumor markers in mucinous epithelial tumors of the appendix has not been previously determined.MethodsIn patients with peritoneal dissemination of a mucinous epithelial malignancy of the appendix, tumor markers CEA and CA 19‐9 were prospectively recorded preoperatively within 1 week prior to definitive treatment. Also, if the appendiceal tumor recurred, the tumor marker was determined. The accuracy of these two tumor markers in the management of this disease was determined for these two specific clinical situations.ResultsCEA was elevated in 56% of 532 patients and CA 19‐9 was elevated in 67.1% of these patients. Although the absolute level of tumor marker did not correlate with prognosis, a normal value indicated an improved survival. CEA was elevated in 35.2% of 110 patients determined to have recurrent disease; CA 19‐9 was elevated in 62.9% and at least one of the tumor markers was elevated in 68.2% of patients. An elevated CEA tumor marker at the time of recurrence indicated a reduced prognosis.ConclusionsBoth CEA and CA 19‐9 tumor markers were elevated in a majority of these patients and should be a valuable diagnostic tool previously underutilized in this group of patients. These tumor markers were also of benefit in the assessment of prognosis in that a normal level indicated an improved prognosis. At the time of a reoperative procedure, CEA and CA 19‐9 tumor markers gave information regarding the progression of disease. These tumor markers have practical value in the management of epithelial appendiceal malignancy with peritoneal dissemination. J. Surg. Oncol. 2004;87:162–166. © 2004 Wiley‐Liss, Inc.