bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retrograde diagenesis, a widespread process on a regional scale
Authors: Nieto F. , Pilar Mata M. , Bauluz B. , Giorgetti G. , Árkai P. , Peacor D. R. 
Published: March 2005

AbstractPelitic and basic rocks occurring within prograde sequences in Portugal, Spain and Hungary have been studied by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The minerals formed in typical prograde reactions define the general sequences, but smectite, chlorite-smectite (corrensite) and/or berthierine were found to have replaced chlorite, whereas kaolinite and mixed-layer illite-smectite replaced illite-muscovite. Alteration occurred under conditions normally associated with diagenesis, subsequent to regional metamorphism, and we therefore refer to such processes with the term “retrograde diagenesis”. In the cases studied and in other cited examples, reactions occurred on a regional basis via pervasive fluids under open-system conditions inferred to be related to tectonic stress. The observed alterations could generally not be inferred from XRD data, although the presence of pure smectite in sediments other than bentonite is suggestive of retrograde relations, especially where other minerals are consistent with a higher grade of diagenesis. Retrograde diagenesis is readily observed through imaging of textures by TEM, however. Textural features show that retrograde reactions are more common than generally assumed, and that care should be used in interpreting geological events where appropriate textural relations are not seen.
Mineralogy, geochemistry and genesis of bentonites of the Ordu area, NE Turkey
Authors: Abdioğlu E. , Arslan M. 
Published: March 2005

AbstractA number of bentonitic clay deposits from the Ordu area (NE Turkey) have been investigated by optical and electron microscopy, X-ray diffraction and chemical analysis. The clays are the alteration products of Late Cretaceous trachytic and trachyandesitic pyroclastic rocks. They contain volcanogenic sanidine, plagioclase, biotite and pumice, along with the diagenetic minerals opal-CT, cristobalite and rare calcite and zeolite (clinoptilolite). Ca-smectite (montmorillonite) is the dominant clay mineral. The rare earth element patterns of all the bentonitic clays are generally similar, although there are variations in the Eu anomaly indicating formation from different types of pyroclastic rocks. Oxygen and hydrogen stable isotope values suggest that the smectite was formed at 20–40°C in pore water of mixed meteoric and marine origin during argillization. These features, together with mass-balance calculations, indicate the enhanced MgO and Sr content of the smectite resulted from formation at shallow burial depths within a dominantly marine environment.
Basalt petrology, zircon ages and sapphire genesis from Dak Nong, southern Vietnam
Authors: Garnier V. , Ohnenstetter D. , Giuliani G. , Fallick A. E. , Phan Trong T. , Hoàng Quang V. , Pham Van L. , Schwarz D. 
Published: March 2005

AbstractBasalts associated with sapphire deposits are widespread in Europe, Africa, Asia and Australia. In Vietnam, blue, green and yellow sapphires are recovered from eluvial and alluvial placers hosted in basaltic fields of the Dak Lak Province. Two distinct basalt suites are recognized in this field: a tholeiitic suite without any xenocrysts and an alkaline suite with mantle and lower crustal xenocrysts. The sapphires are enriched in Fe (0.43 to 1.26 wt.%), with moderate contents of Cr (33–1582 ppm), Ti (35–1080 ppm), Ga (149–308 ppm) and V (28–438 ppm) and they are poor in Zn and Mg. Their O-isotope compositions range from 6.0 to 6.9% and are not in equilibrium with the alkali basalts which have δ18O values between 5.0 and 5.7%. The U-Pb dating of zircons recovered from the basaltic placers provides evidence of two eruptional events: one at ~6.5 Ma followed by another one at ~1 Ma. The petrography of the basalts and the oxygen isotopic composition of the sapphires suggest that the sapphires are xenocrysts and that they crystallized in a deep magma chamber, at the lower continental lithosphere and the upper mantle boundary, in evolved melts issued from the fractionation of alkali basaltic magmas contaminated with lower crustal fluids.
Re-investigation of the crystal structure of whewellite [Ca(C2O4)·H2O] and the dehydration mechanism of caoxite [Ca(C2O4)·3H2O]
Authors: Echigo T. , Kimata M. , Kyono A. , Shimizu M. , Hatta T. 
Published: March 2005

AbstractThe crystal structure of whewellite [Ca(C2O4)·H2O] and the dehydration mechanism of caoxite [Ca(C2O4)·3H2O] have been studied by means of differential thermal analysis, X-ray diffraction (powder and single-crystal) analysis and infrared analysis. The first and second analyses confirmed the direct transformation of caoxite into whewellite without an intermediate weddellite [Ca(C2O4)·2H2O] stage. Infrared spectra obtained from caoxite, weddellite and whewellite emphasize the similarity of the O–H-stretching band and O–C–O-stretching band in whewellite and caoxite and the unique bands of weddellite. The structure refinement at low temperature (123 K) reveals that all the hydrogen atoms of whewellite form hydrogen bonds and the two water molecules prop up the crystal structure by the hydrogen bonds that cause a strong anisotropy of the displacement parameter.Comparing the structural features of whewellite with those of weddellite and caoxite suggests that caoxite and whewellite have a sheet structure consisting of Ca2+ ions and oxalate ions although weddellite does not. It is additionally confirmed that the sheets of caoxite are corrugated by hydrogen bonds but whewellite has flat sheets. The corrugated sheets of caoxite would be flattened by dehydration so the direct transformation of caoxite into whewellite would not occur via weddellite. Essential for this transformation is the dehydration of interlayered water molecules in caoxite leading to the building of the crystal structure of whewellite on its intralayered water molecules. The difference in conformation of water molecules between those two crystal structures may explain the more common occurrence of whewellite than of caoxite in nature.
A novel missense mutation in ABCA1 results in altered protein trafficking and reduced phosphatidylserine translocation in a patient with Scott syndrome
Authors: Albrecht Christiane , McVey John H. , Elliott James I. , Sardini Alessandro , Kasza Ildiko , Mumford Andrew D. , Naoumova Rossi P. , Tuddenham Edward G. D. , Szabo Katalin , Higgins Christopher F. 
Published: March 2005

AbstractScott syndrome (SS) is a bleeding disorder characterized by a failure to expose phosphatidylserine (PS) to the outer leaflet of the platelet plasma membrane. Because the adenosine triphosphate (ATP)–binding cassette transporter A1 (ABCA1) is implicated in the exofacial translocation of PS, we assessed its role in the pathophysiology of a patient with SS. Substantially reduced levels of ABCA1 mRNA were found in the patient's leukocytes, compared with controls. The SS patient was heterozygous for a novel missense mutation c.6064G&gt;A (ABCA1 R1925Q), absent from unaffected family members and controls. Both mutant and wild-type alleles were reduced in mRNA expression, and no causative mutation for this phenomenon was identified in the ABCA1 gene or its proximal promoter, suggesting a putative second mutation in a trans-acting regulatory gene may also be involved in the disorder in this patient. In vitro expression studies showed impaired trafficking of ABCA1 R1925Q to the plasma membrane. Overexpression of wild-type ABCA1 in SS lymphocytes complemented the Ca2+-dependent PS exposure at the cell surface. These data identify a mutation in ABCA1 that contributes to the defective PS translocation phenotype in our patient with SS.
Hematologic differences between African-Americans and whites: the roles of iron deficiency and α-thalassemia on hemoglobin levels and mean corpuscular volume
Authors: Beutler Ernest , West Carol 
Published: March 2005

AbstractThe average results of some laboratory measurements, including the hemoglobin, mean corpuscular volume (MCV), serum transferrin saturation (TS), serum ferritin, and white blood cell count of African-Americans differ from those of whites. Anonymized samples and laboratory data from 1491 African-American and 31 005 white subjects, approximately equally divided between men and women, were analyzed. The hematocrit, hemoglobin, MCV, TS, and white blood cell counts of African-Americans were lower than those of whites; serum ferritin levels were higher. When iron-deficient patients were eliminated from consideration the differences in hematocrit, hemoglobin, and MCV among women were slightly less. The -3.7-kilobase α-thalassemia deletion accounted for about one third of the difference in the hemoglobin levels of African-Americans and whites and neither sickle trait nor elevated creatinine levels had an effect. Among all subjects, 19.8% of African-American women would have been classified as “anemic” compared with 5.3% of whites. Among men, the figures were 17.7% and 7.6%. Without iron-deficient or thalassemic subjects, the difference had narrowed to 6.1% and 2.77% and to 4.29% and 3.6%, respectively. Physicians need to take into account that the same reference standards for hemoglobin, hematocrit, MCV, and TS and the white blood cell count do not apply to all ethnic groups. (Blood. 2005;106:740-745)
Osteo-Promoter Database (OPD) – Promoter analysis in skeletal cells
Authors: Grienberg Inbal , Benayahu Dafna 
Published: March 2005

Abstract
Background
Increasing our knowledge about the complex expression of genes in skeletal tissue will provide a better understanding of the physiology of skeletal cells. The study summarizes transcriptional regulation factors interacting and cooperating at promoter regions that regulate gene expression. Specifically, we analyzed A/T rich elements along the promoter sequences.

Description
The Osteo-Promoter Database (OPD) is a collection of genes and promoters expressed in skeletal cells. We have compiled a new viewer, OPD, as unique database developed and created as an accessible tool for skeletal promoter sequences. OPD can navigate to identify genes specific to skeletal cDNA databases and promoter analysis sites. OPD offers exclusive access to facilitate a dynamic extraction of promoters' gene-specific analyses in skeletal tissue. The data on promoters included in OPD contains cloned promoters or predicted promoters that were analyzed by bioinformatics tools. OPD offers MAR-analysis, which allocates A/T rich elements along these promoter sequences.

Conclusion
The analysis leads to a better insight of proteins that bind to DNA, regulate DNA, and function in chromatin remodeling. The OPD is a distinctive tool for understanding the complex function of chromatin remodeling and transcriptional regulation of specific gene expression in skeletal tissue.
The relation between plasma tyrosine concentration and fatigue in primary biliary cirrhosis and primary sclerosing cholangitis
Authors: ter Borg Pieter CJ , Fekkes Durk , Vrolijk Jan Maarten , van Buuren Henk R 
Published: March 2005

Abstract
Background
In primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) fatigue is a major clinical problem. Abnormal amino acid (AA) patterns have been implicated in the development of fatigue in several non-hepatological conditions but for PBC and PSC no data are available. This study aimed to identify abnormalities in AA patterns and to define their relation with fatigue.

Methods
Plasma concentrations of tyrosine, tryptophan, phenylalanine, valine, leucine and isoleucine were determined in plasma of patients with PBC (n = 45), PSC (n = 27), chronic hepatitis C (n = 22) and healthy controls (n = 73). Fatigue and quality of life were quantified using the Fisk fatigue severity scale, a visual analogue scale and the SF-36.

Results
Valine, isoleucine, leucine were significantly decreased in PBC and PSC. Tyrosine and phenylalanine were increased (p < 0.0002) and tryptophan decreased (p < 0.0001) in PBC. In PBC, but not in PSC, a significant inverse relation between tyrosine concentrations and fatigue and quality of life was found. Patients without fatigue and with good quality of life had increased tyrosine concentrations compared to fatigued patients. Multivariate analysis indicated that this relation was independent from disease activity or severity or presence of cirrhosis.

Conclusion
In patients with PBC and PSC, marked abnormalities in plasma AA patterns occur. Normal tyrosine concentrations, compared to increased concentrations, may be associated with fatigue and diminished quality of life.
Effects of aging and type 2 diabetes on resting and post occlusive hyperemia of the forearm; the impact of rosiglitazone
Authors: Petrofsky Jerrold , Lee Scott , Cuneo Maria 
Published: March 2005

Abstract
Background
Both Diabetes and ageing are associated with reduced vascular endothelial function. The exact relationship between the 2 and any improvements from the insulin sensitizer rosiglitazone have not been explored.

Methods
Thirty controls and sixteen subjects with type 2 diabetes participated in a series of experiments to examine the interrelationships between age, diabetes and endothelial cell function. In subjects with diabetes, the insulin sensitizer rosiglitazone (RSG), a drug also known to improve vascular function, was administered for 3 months to see how it altered these relationships. Resting forearm flows (RF) and blood flows after 4 min of vascular occlusion (PF) were measured as an index of endothelial cell function.

Results
RF, measured by venous occlusion plethysmography, was negatively correlated to both age and diabetes. Administration of RSG for 3 months was associated with an increase in the blood flow response to venous occlusion so that it was not significantly different than that of age matched controls. Total PF in control subjects, compared to subjects with diabetes, averaged 56.58 +/- 12.57 and 13.6 +/- 8.01 cc/100 cc tissue per min respectively, and were significantly different (p < 0.01). After 3 months on RSG, differences between PF in the two groups were no longer evident.

Conclusion
These studies suggest a different mechanism causing a reduction in vascular reactivity with aging and diabetes.
Differential expression of copper-associated and oxidative stress related proteins in a new variant of copper toxicosis in Doberman pinschers
Authors: Spee Bart , Mandigers Paul JJ , Arends Brigitte , Bode Peter , van den Ingh Ted SGAM , Hoffmann Gaby , Rothuizen Jan , Penning Louis C 
Published: March 2005

Abstract

Background
The role of copper accumulation in the onset of hepatitis is still unclear. Therefore, we investigated a spontaneous disease model of primary copper-toxicosis in Doberman pinschers so to gain insights into the pathophysiology of copper toxicosis, namely on genes involved in copper metabolism and reactive oxygen species (ROS) defences.

Results
We used quantitative real-time PCR to determine differentially expressed genes within a target panel, investigating different groups ranging from copper-associated subclinical hepatitis (CASH) to a clinical chronic hepatitis with high hepatic copper concentrations (Doberman hepatitis, DH). Furthermore, a non-copper associated subclinical hepatitis group (N-CASH) with normal hepatic copper concentrations was added as a control. Most mRNA levels of proteins involved in copper binding, transport, and excretion were around control values in the N-CASH and CASH group. In contrast, many of these (including ATP7A, ATP7B, ceruloplasmin, and metallothionein) were significantly reduced in the DH group. Measurements on defences against oxidative stress showed a decrease in gene-expression of superoxide dismutase 1 and catalase in both groups with high copper. Moreover, the anti-oxidative glutathione molecule was clearly reduced in the DH group.

Conclusion
In the DH group the expression of gene products involved in copper efflux was significantly reduced, which might explain the high hepatic copper levels in this disease. ROS defences were most likely impaired in the CASH and DH group. Overall, this study describes a new variant of primary copper toxicosis and could provide a molecular basis for equating future treatments in dog and in man.
Coronary flow reserve in stress-echo lab. From pathophysiologic toy to diagnostic tool
Authors: Rigo Fausto 
Published: March 2005

Abstract
The assessment of coronary flow reserve by transthoracic echocardiography has recently been introduced into clinical practice with gratifying results for the diagnosis of left anterior descending artery disease simultaneously reported by several independent laboratories. This technological novelty is changing the practice of stress echo for 3 main reasons. First, adding coronary flow reserve to regional wall motion allows us to have – in the same sitting – high specificity (regional wall motion) and a high sensitivity (coronary flow reserve) diagnostic marker, with an obvious improvement in overall diagnostic accuracy. Second, the technicalities of coronary flow reserve shift the balance of stress choice in favour of vasodilators, which are a more robust hyperemic stress and are substantially easier to perform with dual imaging than dobutamine or exercise. Third, the coronary flow reserve adds a quantitative support to the exquisitely qualitative assessment of wall motion analysis, thereby facilitating the communication of stress echo results to the cardiological world outside the echo lab. The next challenges involve the need to expand the exploration of coronary flow reserve to the right and circumflex coronary artery and to prove the additional prognostic value – if any – of coronary flow reserve over regional wall motion analysis, which remains the cornerstone of clinically-driven diagnosis in the stress echo lab.
Anthrax vaccine design: strategies to achieve comprehensive protection against spore, bacillus, and toxin
Authors: Wang Julia Y , Roehrl Michael H 
Published: March 2005

AbstractThe successful use ofBacillus anthracisas a lethal biological weapon has prompted renewed research interest in the development of more effective vaccines against anthrax. The disease consists of three critical components: spore, bacillus, and toxin, elimination of any of which confers at least partial protection against anthrax. Current remedies rely on postexposure antibiotics to eliminate bacilli and pre- and postexposure vaccination to target primarily toxins. Vaccines effective against toxin have been licensed for human use, but need improvement. Vaccines against bacilli have recently been developed by us and others. Whether effective vaccines will be developed against spores is still an open question. An ideal vaccine would confer simultaneous protection against spores, bacilli, and toxins. One step towards this goal is our dually active vaccine, designed to destroy both bacilli and toxin. Existing and potential strategies towards potent and effective anthrax vaccines are discussed in this review.
Tyrosine phosphorylation of myosin heavy chain during skeletal muscle differentiation: an integrated bioinformatics approach
Authors: Harney DF , Butler RK , Edwards RJ 
Published: March 2005

Abstract

Background
Previously it has been shown that insulin-mediated tyrosine phosphorylation of myosin heavy chain is concomitant with enhanced association of C-terminal SRC kinase during skeletal muscle differentiation. We sought to identify putative site(s) for this phosphorylation event.

Results
A combined bioinformatics approach of motif prediction and evolutionary and structural analyses identified tyrosines163 and 1856 of the skeletal muscle heavy chain as the leading candidate for the sites of insulin-mediated tyrosine phosphorylation.

Conclusion
Our work is suggestive that tyrosine phosphorylation of myosin heavy chain, whether in skeletal muscle or in platelets, is a significant event that may initiate cytoskeletal reorganization of muscle cells and platelets. Our studies provide a good starting point for further functional analysis of MHC phosphor-signalling events within different cells.
In end-stage renal failure, does infection lead to elevated plasma aluminium and neurotoxicity? Implications for monitoring
Authors: Fenwick Sean , Roberts Edward A , Mahesh Balakrishna S , Roberts Norman B 
Published: March 2005

The well-described long-term effects of sustained exposure to aluminium in patients with end-stage renal failure (ESRF) are a result of uptake and storage of aluminium, leading to cellular toxicity. A case is presented suggesting that this aluminium may be mobilizable, and indicating the consequence of such release. A patient on haemodialysis (HD) presented acutely with infection, a raised CRP, decreased conscious level, impaired cognition and agitation. Subsequent neurological recovery over six to seven days appeared to follow the return of markedly elevated plasma aluminium concentrations to basal (i.e. from 25.2 μmol/L to 2.5 μmol/L; reference range <0.5 μmol/L), coupled with a resolution of the infection. The patient was on long-term aludrox therapy 3 g/day, and showed relative resistance to the exogenous hormone erythropoietin, resulting in a refractory anaemia and suggesting aluminium toxicity. A series of HD patients ( n=5) presenting with bacteraemia, not on aludrox, showed no appreciable rise in the plasma aluminium mean of 1.3 μmol/L (SD 0.9; range 0.6-2.0 μmol/L). We suggest that infection can result in release of tissue aluminium, leading to acutely elevated plasma aluminium concentrations and signs of neurotoxicity. The amount of tissue storage and resultant aluminium release seemed to be related to the use of aluminium hydroxide as a phosphate binder.
Malondialdehyde, glutathione, glutathione peroxidase and homocysteine levels in type 2 diabetic patients with and without microalbuminuria
Authors: Ozdemır Gülsen , Ozden Meltem , Maral Hale , Kuskay Sevinc , Cetınalp Pinar , Tarkun Ilhan 
Published: March 2005

Background: High levels of homocysteine and oxidative stress are known to be associated with premature vascular disease in type 2 diabetes mellitus (DM). The aim of this study was to estimate homocysteine levels and oxidant-antioxidant status and to determine the relationship between them in type 2 diabetic patients with and without microalbuminuria. Methods: Fasting blood samples were obtained from 48 diabetic patients (17 with and 31 without microalbuminuria) and 20 healthy subjects. Serum total homocysteine (tHcy), plasma malondialdehyde (MDA) erythrocyte glutathione (GSH) and glutathione peroxidase (GPx) activity were measured in these patients and the results were compared with those of controls who were chosen among healthy subjects. Results: MDA levels were found to be significantly lower and GSH levels and GPx activities were found to be significantly higher in control subjects when compared with patients with and without microalbuminuria (MDA: P<0.0001, P<0.0001; GSH: P<0.0001, P<0.0001; GPx: P<0.0001, P<0.001, respectively). MDA levels were found to be significantly higher in patients with microalbuminuria compared with patients without microalbuminuria ( P<0.0001), while similarly GSH levels were found to be significantly lower in patients with microalbuminuria ( P<0.0001). Although there were no significant differences with respect to tHcy levels and GPx activities between the microalbuminuric and normoalbuminuric patients ( P>0.05), there was a significant difference with respect to tHcy levels between healthy controls and patients with microalbuminuria ( P<0.05). The serum levels of tHcy correlated best with plasma MDA and erythrocyte GSH concentrations in all diabetic patients ( r=0.549, P<0.0001; r=0.385, P<0.01). Conclusion: Decreased antioxidant levels, increased lipid peroxidation and increased tHcy levels were observed in patients with microalbuminuria. These changes may contribute to vascular disease, which is particularly prevalent in type 2 DM patients with microalbuminuria.