bluuebunny/crossref_metadata_2025_split huggingface dataset:
Further studies on erythrocyte thiamin transport and phosphorylation in seven patients with thiamin‐responsive megaloblastic anaemia
Authors: Rindi G. , Patrini C. , Laforenza U. , Mandel H. , Berant M. , Viana M. B. , Poggi V. , Zarra A. N. F. 
Published: December 2004

SummaryErythrocyte thiamin metabolism and transport were investigated in 7 patients from Brazil, Israel and Italy suffering from thiamin‐responsive megaloblastic anaemia (TRMA) associated with diabetes mellitus and sensorineural deafness. All patients discontinued thiamin therapy for 4–7 days before the investigation. TRMA patients showed invariably reduced total thiamin levels in erythrocytes (percentage reduction compared with healthy controls, −46.8±3%; mean±SEM). The proportions of individual thiamin compounds, expressed as a percentage of total thiamin content, were within the normal range, whereas their absolute amounts were significantly decreased in the following order: thiamin monophosphate > thiamin pyrophosphate > thiamin. Thiamin pyrophosphokinase activity was also reduced as compared with controls (mean reduction±SEM, −25.9±1%). The saturable, specific component of thiamin uptake, which normally prevails at physiological concentrations of thiamin (<2µmol/L), was absent in erythrocytes obtained from TRMA patients, while the non‐saturable (diffusive) component of uptake was normally present.These results confirm observations made previously in two patients and demonstrate that TRMA is consistently associated with a state of thiamin deficiency, which is presumably secondary to reduced thiamin cellular transport and absorption (caused by lack of a membrane‐specific carrier), and to impaired intracellular pyrophosphorylation.
Polyunsaturated fatty acid status in patients with phenylketonuria
Authors: Sanjurjo P. , Perteagudo L. , Soriano J. Rodríguez , Vilaseca A. , Campistol J. 
Published: December 2004

SummaryTo determine whether then−6 andn−3 polyunsaturated fatty acid levels can be affected by the PKU diet, fatty acid composition was studied in PKU subjects and controls together with their lipid intake. The study population consisted of 40 PKU patients treated with a phenylalanine‐restricted diet. Controls were 50 children on whom preoperative tests had been carried out for minor surgery. Methyl esters were obtained from plasma and red blood‐cells and separated by gas chromatography. PKU patients showed lower docosahexaenoic acid levels (22:6n−3) (p<0.001) and highern−6 series levels in plasma (18:2n−6) (p<0.001) and in red blood‐cells (20:4n−6) (p<0.001) than the control population. Since docosahexaenoic and arachidonic acids are fundamental structural components for normal brain development, it seems necessary to consider a dietary adjustment in these patients.
PKU‐related dysgammaglobulinaemia: The effect of diet therapy on IgE and allergic sensitization
Authors: Riva E. , Fiocchi A. , Agostoni C. , Biasucci G. , Sala M. , Banderali G. , Luotti D. , Giovannini M. 
Published: December 2004

SummaryThe effect of diet on the development of immunoallergic signs and symptoms in children with phenylketonuria (PKU) was evaluated. Immunological indices of 58 children with PKU treated with diets were compared to the immunological indices of 58 healthy (non‐PKU) children. In the PKU group, 39 children had been placed on diet therapy within the first month of life; 19 children had been placed on diet therapy after 6 months of age. Total circulating lymphocytes; CD3+, CD4+, CD8+ circulating lymphocytes; and serum IgA, IgM, IgG and total IgE levels were measured for each child. Skin prick tests were performed for common inhalant and food allergens. Every 3 months over the 2‐year period of this study, the signs and symptoms of eczema, allergic rhinitis and asthma were recorded.The PKU group had lower IgG levels (p=0.004) and higher total IgE levels (p=0.0001) than the control group. Significantly lower IgE levels were found in children started on diet therapy within the first month of life compared with those started on diet therapy after 6 months of age (p=0.0001). Allergic sensitization was significantly more frequent in the PKU group (24/58 vs 13/58,z=2.00,p<0.05), but no significant difference in the incidence of eczema and allergic rhinitis was found. Asthma was less frequent in the PKU group than in the control group (5/58 vs 14/58,z=2.09,p<0.05). Thus, diet appeared to prevent the development of immunoallergic signs and symptoms.
Type C Niemann‐Pick disease fibroblasts and their transformed cell lines are hypersensitive to HMG‐CoA reductase inhibitors
Authors: Yamamoto T. , Ohashi T. , Tokoro T. , Maekawa K. , Eto Y. 
Published: December 2004

SummaryThe deficiency of exogenous cholesterol transport within fibroblasts of Niemann‐Pick disease type C (NPC) has been addressed. In this Report we confirmed that the endogenous synthesis of cholesterol within cells was markedly increased in NPC fibroblasts and those transformed by origin‐defective simian virus 40. The transformed fibroblasts and those of the primary culture were hypersensitive to 3‐hydroxy‐3‐methylglutaryl‐coenzyme A reductase inhibitors as a consequence of their dependence on endogenous cholesterol biosynthesis. The transformed fibroblasts should help further biochemical and genetic research in this condition.
The Bishop Ash Bed, a Pleistocene Marker Bed in the Western United States
Authors: Izett G. A. , Wilcox Ray E. , Powers H. A. , Desborough G. A. 
Published: December 2004

Biotite-bearing chalky-white rhyolitic ash, here called the Bishop ash bed, occurs in-middle Pleistocene alluvial and lacustrine deposits at eight localities scattered from California to Nebraska and is correlated with the basal air-fall lapilli of the Bishop Tuff, an ash flow of eastern California, radiometrically dated about 0.7 million years. Correlation of the Bishop ash bed with the air-fall lapilli is made on the basis of similar petrography and on chemistry as determined by electron microprobe, atomic absorption, and emission spectrographic analyses. At five localities the Bishop ash bed lies stratigraphically below a Pearlette-like ash. As more occurrences of the Bishop ash bed are found, it should become an increasingly important dated stratigraphic marker relating middle Pleistocene deposits and events across several geomorphic provinces.Another biotite-bearing chalky-white ash, here called the ash of Green Mountain Reservoir, occurs at three other localities and is distinguishable from the Bishop ash bed by small differences in chemical composition of the glass. The ash of Green Mountain Reservoir is younger than the Bishop ash bed, as shown by the fact that at one locality it lies stratigraphically above the aforementioned bed of Pearlette-like ash.
The Cape Deceit Fauna—Early Pleistocene Mammalian Assemblage from the Alaskan Arctic
Authors: Guthrie R. D. , Matthews John V. 
Published: December 2004

Pleistocene exposures located near Cape Deceit on the south shore of Kotzebue Sound (Alaska) contain a complex sequence of organic sediments which have yielded fossil vertebrates of taxonomic, evolutionary, and zoogeographic significance. Cape Deceit Local Fauna from the Cape Deceit Formation, lowermost of three major stratigraphic units recognized at the site, contains representatives of the genera Canis, Rangifer, Cervus, Ochotona, Lemmus, Microtus, Pliomys, and a newly described genus and species, Predicrostonyx hopkinsi-predecessor of the extant genus Dicrostonyx. In addition to P. hopkinsi, new species of Ochotona, Pliomys, and Microtus are described from the Cape Deceit Local Fauna. the stage of evolution of Microtus deceitensis sp. n. and P. hopkinsi sp. n. indicate that the Cape Deceit Formation is at least of pre-Cromerian age. This assumption is substantiated by the stratigraphy of the overlying Inmachuk and Deering formations, fossils from these units (including Dicrostonyx torquatus and D. henseli), and C-14 dates. The Cape Deceit Local Fauna, therefore, contains the earliest North American record of several of the included genera in addition to the only North American record of Pliomys.Stratigraphic features at the exposure indicate that the Cape Deceit Local Fauna mammals lived in a treeless (tundra) environment showing that the contemporary tundra mammalian fauna has a lengthy arctic-adapted evolutionary history. We postulate the existence in northeastern Eurasia and Alaska of a Pleistocene-Recent “Beringian” mammalian realm which has at times contributed to the fauna of more southern regions of the Palaerctic and Nearctic. The fact that this southern movement of arctic-adapted or arctic-derived Beringian mammals occurred at different times in Europe and North America (interpreted by some as indicating the existence of a “Beringian filter-bridge”) is, we think, due largely to differences of continental physiography and Pleistocene geography south of the Beringian area.
Equilibrium-line Altitudes of Late Quaternary Glaciers in the Southern Alps, New Zealand
Authors: Porter Stephen C. 
Published: December 2004

AbstractEquilibrium-line altitudes (ELA's) of former glaciers in the Tasman River-Lake Pukaki drainage basin of the Southern Alps were reconstructed from glacial-geologic data on former ice limits by using an assumed accumulation-area ratio of 0.6 ± 0.05. Late Holocene (Neoglacial) ELA's were depressed 140 m below present levels, whereas those of four late Pleistocene ice advances were depressed 500 m (Birch Hill), 750 m (Tekapo), 875 m (Mt. John), and 1050 m (Balmoral). Reconstructed ELA gradients are approximately parallel to one another and range from 19 to 23 m km−1. Although vertical movement on active faults and isostatic tilting due to deglaciation have both contributed to modification of reconstructed ELA gradients from their original values, the maximum resulting effect probably amounts to less than 2.0 m km−1 and is undetectable from present data.
Obsidian Hydration Dating of Volcanic Events
Authors: Friedman Irving , Obradovich John 
Published: December 2004

AbstractObsidian hydration dating of volcanic events had been compared with ages of the same events determined by the 14C and K — Ar methods at several localities. The localities, ranging in age from 1200 to over 1 million yr, include Newberry Craters, Oregon; Coso Hot Springs, California; Salton Sea, California; Yellowstone National Park, Wyoming; and Mineral Range, Utah. In most cases the agreement is quite good. A number of factors including volcanic glass composition and exposuretemperature history must be known in order to relate hydration thickness to age. The effect of composition can be determined from chemical analysis or the refractive index of the glass. Exposure-temperature history requires a number of considerations enumerated in this paper.
Plankton Ecology and the Paleoceanographic–Climatic Record
Authors: Loubere Paul 
Published: December 2004

AbstractThe paleoceanographic–climatic record represented by deep-sea microfossils reflects conditions for only certain times of the year. Also, the relative abundances of microfossil species in deep-sea sediments do not usually reflect only one paleoceanographic variable, such as temperature. Rather, species distributions represent the integration of many factors that control biological production in the oceans. This influences the information on past climates that can be extracted from fossil material. The seasonal limitation is due to the cyclic nature of biological production in the open ocean. Case studies of the sediment record in the Atlantic for two species of planktonic Foraminifera, left-coiling Neogloboquadrina pachyderma (Ehrenberg) and Globigerinoides ruber (d'Orbigny), illustrate seasonal bias in environmental data reported by the relative abundances of species in deep-sea sediments. In addition, the study of G. ruber illustrates the operation of two oceanographic parameters in controlling a species distribution. These examples demonstrate that the environmental signal in the sediments is the result of the interplay of the ecological tolerance of the plankton species with seasonally variable biological and physical properties of the upper ocean.
Amino Acid Geochemistry of Fossil Bones from the Rancho La Brea Asphalt Deposit, California
Authors: McMenamin Mark A. S. , Blunt David J. , Kvenvolden Keith A. , Miller Scott E. , Marcus Leslie F. , Pardi Richard R. 
Published: December 2004

AbstractLow aspartic acid d:l ratios and modern collagenlike concentration values indicate that amino acids in bones from the Rancho La Brea asphalt deposit, Los Angeles, California are better preserved than amino acids in bones of equivalent age that have not been preserved in asphalt. Amino acids were recovered from 10 Rancho La Brea bone samples which range in age from less than 200 to greater than 36,000 yr. The calibrated rates of aspartic acid racemization range from 2.1 to 5.0 × 10−6yr−1. Although this wide range of rate constants decreases the level of confidence for age estimates, use of the larger rate constant of 5.0 × 10−6yr−1provides minimum age estimates which fit the known stratigraphic and chronologic records of the Rancho La Brea deposits.
Chronologic and Environmental Implications of a New Genus of Fossil Deer from Late Wisconsin Deposits at Toronto, Canada
Authors: Churcher C. S. , Peterson R. L. 
Published: December 2004

AbstractA new cervine deer (Torontoceros hypogaeus), described from a partial cranium with portions of the main antler beams, has been recovered from deposits of early Lake Ontario age on the exposed bench of Glacial Lake Iroquois at Toronto, Ontario, Canada. The deer was about the size of a caribou, has heavy antlers that lie chiefly in a nearly horizontal plane, and its beams are bowed anteriorly. The tines are not flattened, the brow tines are asymmetrical, and no evidence of surface roughening or palmation of the beam is found. A 14C date of 11,315 ± 325 yr B.P. obtained on the antler allows the date at which Glacial Lake Iroquois drained to be revised to before 11,400 yr B.P. Spruce (Picea), pine (Pinus), and sedges (Cyperaceae) are major components of the associated pollen spectrum, which implies a typically interstadial or postglacial climate in which mixed forests grew in the Toronto area.
Carbon Isotopic Changes in Benthic Foraminifera from the Western South Atlantic: Reconstruction of Glacial Abyssal Circulation Patterns
Authors: Curry W. B. , Lohmann G. P. 
Published: December 2004

AbstractOxygen- and carbon-isotopic analyses have been performed on the benthic foraminifer Planulina wuellerstorfi in seven Late Quaternary cores from the Vema Channel-Rio Grande Rise region. The cores are distributed over the water-depth interval of 2340 to 3939 m, which includes the present transition from North Atlantic Deep Water (NADW) to Antarctic Bottom Water (AABW).The carbon-isotopic records in the cores vary as a function of water depth. The shallowest and deepest cores show no significant glacial-interglacial difference in δ13C. Four of the five cores presently located in the NADW have benthic foraminiferal δ13C that is lower during glacial isotopic stages. Based on bathymetric gradients in δ13C, we conclude that, like today, there were two water masses present in the Vema Channel during glacial intervals: a water mass enriched in 13C overlying another water mass depleted in 13C. The largest gradient of change of δ13C with depth, however, occurred at 2.7 km, ∼ 1 km shallower than the present position of this gradient.On the basis of paleontologic and sedimentologic evidence, we consider it unlikely that the NADW:AABW transition shallowed to this level. Reduced carbon-isotopic gradients between the deep basins of the North Atlantic and Pacific Oceans during the last glaciation suggest that production of NADW was reduced. Lower production of NADW may have modified the local abyssal circulation pattern in the Vema Channel region.
Pseudo-Ice-Wedge Casts of Connecticut, Northeastern United States
Authors: Black Robert F. 
Published: December 2004

AbstractSince 1965, ice-wedge casts have been reported in deposits of sand and gravel in Connecticut. These are wedge forms up to 1.1 m wide and many meters high. Most are single forms, not in polygonal array. They are found in adjoining states as well. Their distribution, dimensions, structure, and fabric and an assessment of the former physical environment preclude their origin as permafrost features. They appear to be tension fractures produced by the loading of coarse clastics on fine clastics near and below the water table where sediments creep toward a stream or depression. Locally movement started with kettle formation during deglaciation. However, some wedges cut horizontal layers of iron-coated sand and gravel and must be younger than those distinctly postglacial phenomena. Moreover, modern B horizons of the overlying soil have moved down into some wedges more than 2 m, indicating that fracturing is still active today. Complex fracture fillings in bedrock also have been attributed to a permafrost origin, but this too seems unlikely.
Extinct Mountain Goat (Oreamnos harringtoni) in Southeastern Utah
Authors: Mead Jim I. , Agenbroad Larry D. , Phillips Arthur M. , Middleton Larry T. 
Published: December 2004

AbstractThe extinct Harrington's mountain goat (Oreamnos harringtoni Stock) is predominantly known from dry cave localities in the Grand Canyon, Arizona, in addition to two sites in the Great Basin, Nevada, and from San Josecito Cave, Nuevo Leon, Mexico. A dry shelter in Natural Bridges National Monument, on the central Colorado Plateau, southeastern Utah, preserves numerous remains of the extinct mountain goat in addition to pack rat middens. Remains from a 100-cm stratigraphic profile indicate that O. harringtoni lived on the plateau >39,800 yr B.P., the oldest directly dated find of extinct mountain goat. Plant macrofossils indicate that Engelmann's spruce (Picea engelmannii), limber pine (Pinus flexilis), rose (Rosa cf. woodsii), and Douglas fir (Pseudotsuga menziesii) grew during the late Pleistocene where a riparian and a pinyon-juniper (Pinus edulis-Juniperus osteosperma) community now predominates; Douglas fir are found only in mesic, protected, north-facing areas. Limber pine, Douglas fir, bark, and grasses were the major dietary components in the dung. A springtime diet of birch (Betula) is determined from pollen clumps in dung pellets.
Source and Origin of Roxana Silt and Middle Wisconsinan Midcontinent Glacial Activity
Authors: Johnson W. Hilton , Follmer Leon R. 
Published: December 2004

AbstractThick Roxana Silt (middle Wisconsinan) in central and southwestern Illinois traditionally has been interpreted as loess derived from valley-train deposits in the ancient Mississippi River valley. Winters et al. (H. A. Winters, J. J. Alford, and R. L. Rieck, Quaternary Research 29, 25–35, 1988) recently suggested that the Roxana was not directly related to glacial activity, but was derived from sediment produced by increased shoreline and spillway erosion associated with a fluctuating ancestral Lake Michigan. Because (1) paleoenvironmental and paleohydrologic conditions inferred in the hypothesis are unlikely for a loess depositional system and (2) loess did not accumulate during late Wisconsinan deglaciation under conditions similar to those hypothesized, we suggest the hypothesis should be rejected. Roxana distribution suggests the major source was drainage from the upper Mississippi River valley, and variations in loess thickness in Illinois can be explained by consideration of valley width, depth, orientation, and postdepositional erosion. Tills in the headwaters region of the ancient Mississippi drainage system in Minnesota and Wisconsin occur in the appropriate stratigraphic position and have colors and mineralogic compositions that suggest they could be the parent till of the Roxana. We believe a valley-train source for thick Roxana is most probable and urge continued consideration of middle Wisconsinan glaciation in the upper Great Lakes area.
Pre-Wisconsinan Mammals from Jamaica and Models of Late Quaternary Extinction in the Greater Antilles
Authors: MacPhee R. D. E. , Ford Derek C. , McFarlane Donald A. 
Published: December 2004

AbstractThe vertebrate fauna recovered from indurated conglomerates at Wallingford Roadside Cave (central Jamaica) is shown to be in excess of 100,000 yr old according to uranium series and electron spin resonance dating. The Wallingford local fauna is therefore pre-Wisconsinan in age, and Roadside Cave is now the oldest radiometrically dated locality in the West Indies containing identifiable species of land mammals. In the absence of a good radiometric record for Quaternary paleontological sites in the Caribbean, there is no satisfactory basis for determining whether most extinct Antillean mammals died out in a “blitzkrieg”-like event immediately following initial human colonization in the mid-Holocene. Fossils of Clidomys (Heptaxodontidae, Caviomorpha), the giant Wallingford rodent, have never been found in situ in sediments of demonstrably Holocene age, and its extinction may antedate the middle Holocene. This is also a possibility for the primate Xenothrix mcgregori, although its remains have been found in loose cave earth. A major, climate-driven bout of terrestrial vertebrate extinction at about 14,000–12,000 yr B.P. has been hypothesized for the West Indies by G. Pregill and S. L. Olson (Annual Review of Ecology and Systematics 12, 75–98, 1981), but at present there is nothing to connect the disappearance of Clidomys with this event either. Quaternary extinctions in the Caribbean may prove to be of critical significance for evaluating the reality of New World blitzkrieg, but not until an effort is mounted to constrain them rigorously using modern radiometric approaches.
Climatic Change at the End of the Last Glaciation in Japan Inferred from Pollen in Three Cores from the Northwest Pacific Ocean
Authors: Heusser Linda E. , Morley Joseph J. 
Published: December 2004

AbstractLate-glacial pollen time-series from high-sedimentation-rate marine cores KH79-3-C6, CH84-04, and CH84-14 show the rise of successional vegetation (typified by Betula) during the replacement of boreal forest types (Picea and Pinus) by thermophilous Quercus forests. Variations in these three marine pollen records replicate the trends and timing of pollen records from Japan and the structure and timing of vegetation and climatic changes on the Pacific coast of Japan since the last glacial maximum. In marine cores KH79-3-C6, CH84-04, and CH84-14, oxygen isotope and/or marine faunal data have been interpreted as evidence of a cooling event in the northwest Pacific Ocean which is coeval with the Younger Dryas chronozone. Pollen records from these northwest Pacific cores, like those from Japan, do not exhibit a regionally replicated, statistically robust, pollen assemblage which can be unambiguously interpreted as evidence of a late-glacial climatic reversal between ca. 11,000 and 10,000 yr B.P. The apparent disparity between the terrestrial (pollen) and marine evidence for a climatic oscillation during the Younger Dryas chron in northeast Asia further complicates the variable record of this brief late-glacial event.
Displacement of Salt by the Laurentide Ice Sheet
Authors: White William A. 
Published: December 2004

AbstractIn central New York, deformation of salt of the Salina Formation by the Laurentide Ice Sheet is shown by a thinning of the salt stratum in and near the outcrop zone where it was overridden by the ice sheet and by a thickening down-dip near the glacial limit. Less definitive suggestions of deformation by glacial overriding of the Salina outcrop zone in northeastern Ohio are seen in salt-cored anticlines in the vicinity of the glacial limit. In the lower peninsula of Michigan, isopachs of salt curve around Saginaw Bay, which suggests that the salt was displaced southwestward, away from the bay, by pressure of the Saginaw lobe of the ice sheet. All but one of the major Paleozoic salt deposits of North America lie in a zone that girdles two-thirds of the Canadian Shield from where glacial erosion removed all but occasional outliers of Phanerozoic strata.