bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interstitial lung disease in patients with ataxia‐telangiectasia
Authors: Schroeder Scott A. , Swift Michael , Sandoval Claudio , Langston Claire 
Published: March 2005

AbstractAtaxia‐telangiectasia (A‐T) is an autosomal‐recessive multiorgan disease characterized by progressive neurologic deterioration in which the most common causes of death are diseases of the respiratory system and cancers. The aim of this retrospective study was to delineate the clinical, radiographic, and pathologic manifestations of the chronic progressive interstitial lung disease seen in patients with A‐T. The medical records of 97 patients with A‐T and chronic lung disease were reviewed. Interstitial lung disease (ILD) was specifically diagnosed in 25 of 97 patients. None of these patients had evidence of an infectious process preceding the onset of their lung disease, and none had lasting clinical improvement after treatment with antibiotics. Although many medications were used to treat their ILD, only treatment with systemic corticosteroids early in the course of their illness was associated with clinical and radiographic improvement. Nineteen of these 25 patients with ILD died within 24 months of the onset of their ILD, and of 7 patients treated with corticosteroids, 5 are still alive. Recognition of interstitial lung disease in patients with A‐T and its early treatment could reduce or eliminate pulmonary disease as a leading cause of death for these patients. © 2005 Wiley‐Liss, Inc.
Empirical lipid propensities of amino acid residues in multispan alpha helical membrane proteins
Authors: Adamian Larisa , Nanda Vikas , DeGrado William F. , Liang Jie 
Published: March 2005

AbstractCharacterizing the interactions between amino acid residues and lipid molecules is important for understanding the assembly of transmembrane helices and for studying membrane protein folding. In this study we develop TMLIP (TransMembrane helix‐LIPid), an empirically derived propensity of individual residue types to face lipid membrane based on statistical analysis of high‐resolution structures of membrane proteins. Lipid accessibilities of amino acid residues within the transmembrane (TM) region of 29 structures of helical membrane proteins are studied with a spherical probe of radius of 1.9 Å. Our results show that there are characteristic preferences for residues to face the headgroup region and the hydrocarbon core region of lipid membrane. Amino acid residues Lys, Arg, Trp, Phe, and Leu are often found exposed at the headgroup regions of the membrane, where they have high propensity to face phospholipid headgroups and glycerol backbones. In the hydrocarbon core region, the strongest preference for interacting with lipids is observed for Ile, Leu, Phe and Val. Small and polar amino acid residues are usually buried inside helical bundles and are strongly lipophobic. There is a strong correlation between various hydrophobicity scales and the propensity of a given residue to face the lipids in the hydrocarbon region of the bilayer. Our data suggest a possibly significant contribution of the lipophobic effect to the folding of membrane proteins. This study shows that membrane proteins have exceedingly apolar exteriors rather than highly polar interiors. Prediction of lipid‐facing surfaces of boundary helices using TMLIP1 results in a 54% accuracy, which is significantly better than random (25% accuracy). We also compare performance of TMLIP with another lipid propensity scale, kPROT, and with several hydrophobicity scales using hydrophobic moment analysis. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Hydrothermal Syntheses and Structural Studies of Lanthanide Coordination Polymers Involving In‐Situ Decarboxylation and their Luminescence Properties
Authors: Han Zheng‐Bo , Cheng Xiao‐Ning , Li Xiao‐Feng , Chen Xiao‐Ming 
Published: March 2005

AbstractLanthanide coordination polymers with the formula [Ln(pydc)2]·H2O (Ln = La, 1; Nd, 2; pydc = 3,4‐pyridinedicarboxylate) and [Ln(pydc)(ina)(H2O)2] (Ln = Sm, 3; Eu, 4; Tb, 5; Dy, 6; pydc = 3,4‐pyridinedicarboxylate, ina = isonicotinate) were synthesized by treating LnIII nitrates with 3,4‐pyridinedicarboxylic acid under hydrothermal conditions. Single‐crystal and powder X‐ray diffraction studies indicate that these lanthanide coordination polymers adopt two different structures. The lighter lanthanide compounds 1 and 2 consist of extended two‐dimensional layer structures with the thickness of ca. 1.7 nm. While the heavier lanthanide compounds 3‐6 have pydc‐bridged double chain structures with one chelating carboxylate group of ina ligand and two water molecules on each metal center. Interestingly, decarboxylation occurred and pydc was partially transformed into ina in the hydrothermal reactions of 3‐6. The fluorescence activities of compounds 4 and 5 are reported.
The Synthesis by Decarboxylation Reactions and Crystal Structures of 1, n–Bis(diphenylphosphino)alkane(pentafluorophenyl)‐platinum(II) Complexes
Authors: Deacon Glen B. , Elliott Philip W. , Erven Anja P. , Meyer Gerd 
Published: March 2005

AbstractDecarboxylation reactions between the complexes cis–[PtCl2L] (L = 1, n–bis(diphenylphosphino)–ethane (n = 2, dppe), –propane (n = 3, dppp) or –butane (n = 4, dppb)) and thallium(I) pentafluorobenzoate in pyridine give cis–[PtCl(C6F5)L] and cis–[Pt(C6F5)2L] complexes in high yields with short reaction times. X–ray crystal structures of cis–[PtCl(C6F5)(dppe)] · 0.5 C5H5N, cis–[PtCl(C6F5)(dppp)], cis–[PtCl(C6F5)(dppb)] · C3H6O, cis–[Pt(C6F5)2L] (L = dppe, dppp and dppb) and the reactants cis–[PtCl2(dppp)] (as a CH2Cl2 solvate) and cis–[PtCl2(dppb)] show monomeric structures with chelating diphosphine ligands in all cases rather than dimers with bridging diphosphines. 31P NMR data are consistent with these structures in solution.
2J(P,C) and 3J(P,C) Coupling Constants in Some New Phosphoramidates. Crystal Structures of CF3C(O)N(H)P(O)[N(CH3)(CH2C6H5)]2 and4‐NO2‐C6H4N(H)P(O)[4‐CH3‐NC5H9]2
Authors: Gholivand Khodayar , Shariatinia Zahra , Pourayoubi Mehrdad 
Published: March 2005

AbstractSome new phosphoramidates were synthesized and characterized by 1H, 13C, 31P NMR, IR spectroscopy and elemental analysis. The structures of CF3C(O)N(H)P(O)[N(CH3)(CH2C6H5)]2 (1) and 4‐NO2‐C6H4N(H)P(O)[4‐CH3‐NC5H9]2 (6) were confirmed by X‐ray single crystal determination. Compound 1 forms a centrosymmetric dimer and compound 6 forms a polymeric zigzag chain, both via ‐N‐H…O=P‐ intermolecular hydrogen bonds. Also, weak C‐H…F and C‐H…O hydrogen bonds were observed in compounds 1 and 6, respectively. 13C NMR spectra were used for study of 2J(P,C) and 3J(P,C) coupling constants that were showed in the molecules containing N(C2H5)2 and N(C2H5)(CH2C6H5) moieties, 2J(P,C)>3J(P,C). A contrast result was obtained for the compounds involving a five‐membered ring aliphatic amine group, NC4H8. 2J(P,C) for N(C2H5)2 moiety and in NC4H8 are nearly the same, but 3J(P, C) values are larger than those in molecules with a pyrrolidinyl ring. This comparison was done for compounds with six and seven‐membered ring amine groups. In compounds with formula XP(O)[N(CH2R)(CH2C6H5)]2, 2J(P,CH2)benzylic>2J(P,CH2)aliphatic, in an agreement with our previous study.
Shorebird Use of Coastal Wetland and Barrier Island Habitat in the Gulf of Mexico
Authors: Withers Kim 
Published: March 2005

The Gulf Coast contains some of the most important shorebird habitats in North America. This area encompasses a diverse mixture of estuarine and barrier island habitats with varying amounts of freshwater swamps and marshes, bottomland hardwood forests, and coastal prairie that has been largely altered for rice and crawfish production, temporary ponds, and river floodplain habitat. For the purposes of this review, discussion is confined to general patterns of shorebird abundance, distribution, and macro- and microhabitat use in natural coastal, estuarine, and barrier island habitats on the Gulf of Mexico Coast. The following geographic regions are considered: Northwestern Gulf (Rio Grande to Louisiana-Mississippi border), Northeastern Gulf (Mississippi to Florida Keys), and Mexico (Rio Grande to Cabo Catoche [Yucatan Strait]).Wintering and migrating shorebirds are most abundant along the Gulf Coast in Texas and Tamaulipas, particularly the Laguna Madre ecosystem. Other important areas are the Southwest Coast region of Florida and the area between Laguna Terminos and Puerto Progresso in Mexico. In general, relative abundances of shorebirds increase from north to south, and decrease south of the Tropic of Cancer (23° 27’ N). Based on bimonthly maximum counts within 5° latitudinal bands, the region between 25–30° N is used most heavily by wintering and spring migrating birds.Non-vegetated coastal wetland habitats associated with bays, inlets and lagoons, particularly tidal flats, and sandy beaches are the habitats that appear to be favored by wintering and migrating shorebirds. In general, these habitats tend to occur as habitat complexes that allow for movement between them in relation to tidal flooding of bay-shore habitats. This relationship is particularly important to Piping Plover and may be important to others.Although vegetated habitats are used by some species, they do not appear to attract large numbers of birds. This habitat is most widespread between the Texas-Louisiana border and the Florida Panhandle region, but it has not been studied extensively. Shorebird abundance and habitat use in this area need to be addressed.
Effects of Climate Warming, North Atlantic Oscillation, and El Niño-Southern Oscillation on Thermal Conditions and Plankton Dynamics in Northern Hemispheric Lakes
Authors: Gerten Dieter , Adrian Rita 
Published: March 2005

Impacts of climate warming on freshwater ecosystems have been documented recently for a variety of sites around the globe. Here we provide a review of studies that report long-term (multidecadal) effects of warming trends on thermal properties and plankton dynamics in northern hemispheric lakes. We show that higher lake temperatures, shorter periods with ice cover, and shorter stagnation periods were common trends for lakes across the hemisphere in response to the warmer conditions. Only for shallow dimictic lakes was it observed that deep-water temperatures decreased. Moreover, it became evident that phytoplankton dynamics and primary productivity altered in conjunction with changes in lake physics. Algal spring blooms developed early and were more pronounced in several European lakes after mild winters with short ice cover periods, and primary productivity increased in North American lakes. Effects of elevated temperatures on zooplankton communities were seen in an early development of various species and groups, as is documented for cladocerans, copepods, and rotifers in European lakes. Furthermore, thermophile species reached higher abundance in warmer years.Obviously, the nature of responses is species specific, and depends on the detailed seasonal patterning of warming. Complex responses such as effects propagating across trophic levels are likely, indicating that observed climate—ecosystem relationships are not generally applicable. Nonetheless, the picture emerges that climate-driven changes in freshwater ecosystems may be synchronised to a certain extent among lakes even over great distances if climatic influences are not masked by anthropogenic impacts or differences in lake morphology. Macro-scale climatic fluctuations — such as the North Atlantic Oscillation or the El Niño-Southern Oscillation — were identified as the most important candidates responsible for such coherence, with the former predominating in Europe and the latter in North America. We emphasise, however, that the driving mechanisms and the future behaviour of these oscillations are rather uncertain, which complicates extrapolation of observed effects into the future. Thus, it is necessary to quantify the most important climate—ecosystem relationships in models of appropriate complexity. Such models will help elucidate the multiple pathways climate affects freshwater ecosystems, and will indicate possible adverse effects of a warmer future climate.
Carbon Reservoirs in Temperate South American Nothofagus Forests
Authors: Baswald Klaus , Lencinas Jose D. , Loguercio Gabriel 
Published: March 2005

Humans are influencing the global carbon (C) cycle due to the combustion of fossil fuels and due to changes in land use management. These activities are fostering the manmade greenhouse effect and thus global climate change. Negative effects for life on earth are accounted for.Among others the international climate debate focused attention on forests and forestry, knowing about their considerable influence on global climate change. Whilst the global C budget is described fairly well, there is a lack of regional data describing the C reservoirs and flows in detail. This has to be constituted especially for forests in developing countries.This paper presents an investigation at regional scale of the C reservoirs in a South American forest ecosystem. The investigation puts emphasis on the area and stand volume estimation and the development of expansion and reduction factors. Vegetation types are classified and stratified, determining the corresponding areas and estimating the stand volume. Converting factors are developed to calculate C in branches and roots as a percentage of standing wood measured by inventories.
Evolutionary Theories of Aging and Longevity
Authors: Gavrilov Leonid A. , Gavrilova Natalia S. 
Published: March 2005

The purpose of this article is to provide students and researchers entering the field of aging studies with an introduction to the evolutionary theories of aging, as well as to orient them in the abundant modern scientific literature on evolutionary gerontology. The following three major evolutionary theories of aging are discussed: 1) the theory of programmed death suggested by August Weismann, 2) the mutation accumulation theory of aging suggested by Peter Medawar, and 3) the antagonistic pleiotropy theory of aging suggested by George Williams. We also discuss a special case of the antagonistic pleiotropy theory, the disposable soma theory developed by Tom Kirkwood and Robin Holliday. The theories are compared with each other as well as with recent experimental findings. At present the most viable evolutionary theories are the mutation accumulation theory and the antagonistic pleiotropy theory; these theories are not mutually exclusive, and they both may become a part of a future unifying theory of aging.Evolutionary theories of aging are useful because they open new oppor-tunities for further research by suggesting testable predictions, but they have also been harmful in the past when they were used to impose limitations on aging studies. At this time, the evolutionary theories of aging are not ultimate completed theories, but rather a set of ideas that themselves require further elaboration and validation. This theoretical review article is written for a wide readership.
Differences Between Lovastatin and Simvastatin Hydrolysis in Healthy Male and Female Volunteers: Gut Hydrolysis of Lovastatin is Twice that of Simvastatin
Authors: Vree Tom B. , Dammers Erik , Ulc Ivan , Horkovics-Kovats Stefan , Ryska Miroslav , Merkx IJsbrand 
Published: March 2005

The aim of this pharmacokinetic evaluation was to show the effect of the extra methyl group in simvastatin on esterase hydrolysis between lovastatin and simvastatin in male and female volunteers. This study was based on the plasma concentration-time curves and the pharmacokinetics of lovastatin and simvastatin with its respective active metabolite statin-β-hydroxy acid obtained from two different bioequivalence studies, each with 18 females and 18 males. Results were: 1-The group of female volunteers showed a higher yield of the active metabolite β-hydroxy acid than the group of males (p < 0.002) for both lovastatin and simvastatin. This difference was not related to the body weight of both groups. 2-In the male/female groups, subject-dependent yield of active metabolite β-hydroxy acid was demonstrated, which was independent of the formulation. The variation in plasma/liver hydrolysis resulted in a fan-shaped distribution of data points when the AUCtlovastatin was plotted vs. that of the β-hydroxy acid metabolite. In the fan of data points, subgroups could be distinguished, each showing a different regression line and with a different Y-intercept (AUCtβ-hydroxy acid). 3-Lovastatin hydrolysis was higher than simvastatin hydrolysis. 4-It was possible to discriminate between hydrolysis of both lovastatin and simvastatin by plasma/liver or tissue esterase activity.The three subgroups of subjects (males/females) showing different but high yield of statin β-hydroxy acid can be explained by variable hydrolysis of plasma and hepatic microsomal and cytosolic carboxyesterase activity.This study showed clearly that despite the subject-dependent hydrolysis of lovastatin/simvastatin to the active metabolite, males tend to hydrolyse less than females. The extra methyl group in simvastatin results in less hydrolysis due to steric hindrance.
Severe gastritis in the Peruvian Andes
Authors: Recavarren‐Arce S , Ramirez‐Ramos A , Gilman R H , Chinga‐Alayo E , Watanabe‐Yamamoto J , Rodriguez‐Ulloa C , Miyagui J , Passaro D J , Eza D 
Published: March 2005

Objective : To compare the Helicobacter pylori‐associated pathology in gastric biopsies taken from patients living at sea level with those taken from patients living at high altitude.Methods and results : We included 38 patients from a hospital in the Andean city of La Oroya, Peru, located at 3700 m in altitude, and 40 control patients taken from Comas Clinic located in the city of Lima at sea level. Fibrepanendoscopy and multiple biopsies were performed in all the patients followed by histopathological examination. In the antrum, patients from the Andean town had a higher prevalence of glandular lymphoid adherence lesions, active germinal centres, moderate to severe chronic atrophic gastritis, intestinal metaplasia and moderate to severe total deep gland loss, than did patients from the coastal town. Furthermore, the severity of the histological lesions seen in the gastric body and cardia was significantly greater in the high‐altitude patients than in those from sea level.Conclusion : This study suggests that the severity of H. pylori‐associated gastric lesions seen on histopathological examination is greater in patients living at high altitude, the cause of which is most probably multifactorial but nonetheless principally altitude related.
Ultrastructural and Rheological Properties of Bovine Vaginal Fluid and its Relation to Sperm Motility and Fertilization: a Review
Authors: Rutllant J , López‐Béjar M , López‐Gatius F 
Published: March 2005

ContentsThe tubular genital organs of the mammalian female reproductive tract provide different luminal microenvironments that can act as an aid or a barrier to gamete transport and the first steps of embryonic development. The mechanism of sperm transport through the genital tract has not been fully established but, first of all, sperm cells encounter and need to overcome mucous‐like secretions to reach the site where fertilization occurs. One of these secretions, vaginal fluid, is a complex biological product, which is mainly derived from cervical mucus. In this review, we focus on recent studies that describe the relationships between the ultrastructural and rheological properties of bovine vaginal fluid and sperm motion. In the light of this, we propose bovine vaginal fluid as a morphofunctional model for the study of sperm transport in mammals.
Preliminary Evaluation of a Unique Freezing Technology for Bovine Spermatozoa Cryopreservation
Authors: Cotter PZ , Goolsby HA , Prien SD 
Published: March 2005

ContentsArtificial insemination (AI) and semen cryopreservation has significantly improved the breeding potential of male animals. However, current freezing techniques commonly result in reduced semen quality. Ten years ago, a unique freezing technology (UFT) was developed for the freezing of foodstuffs and other materials. Previous work from this laboratory has demonstrated the UFT to be a superior method of freezing for a number of cell types. In a preliminary study, the UFT was compared with the conventional freezing methodology of bovine semen. Semen samples were collected from an angus (Bull A) and a gelbivich bull (Bull B), prepared using a conventional bovine cryoprotectant, and frozen in the UFT or in liquid nitrogen (LN) mist. The samples were stored in LN before being thawed and assessed for the semen parameters of motility and forward progression. Preliminary results suggest the UFT is equivalent to current techniques in the cryopreservation and recovery of bovine semen, and with modification, possibly a superior technique for semen freezing. Further studies using larger sample populations, and using a CASA system to evaluate motility, forward progression and linearity are merited.
The Effect of Oestradiol, Progesterone and Heparin on Bovine Spermatozoa Function After Thawing
Authors: Lukoseviciute K , Zilinskas H , Januskauskas A 
Published: March 2005

ContentsThe present experiment was designed to determine the effects of various biologically active substances, such as oestradiol (OE), progesterone (P4) and heparin (Hep) alone or in combination on sperm plasma membrane scrambling, capacitation and acrosome reaction (AR) of post‐thaw bovine spermatozoa. Spermatozoa were incubated for 180 min in capacitation medium supplemented with (i) 1 μg/ml OE; (ii) 1 μg/ml P4; (iii) 1 μg/ml OE and 1 μg/ml P4; (iv) 1 μg/ml OE and 5 μg/ml Hep; (v) 1 μg/ml P4 and 5 μg/ml Hep; (vi) 1 μg/ml OE, 1 μg/ml P4 and 5 μg/ml Hep. At predetermined time intervals aliquots were taken to assess sperm plasma membrane scrambling, or capacitation (AR induced by lysophosphatidylcholine) in spermatozoa. The second experiment was aimed to study the effects of OE, P4 and OE/P4 as potential inducers of AR in Hep‐capacitated spermatozoa. Plasma membrane scrambling was assessed by a flow cytometer, using Merocyanine staining. Acrosomal status and viability of spermatozoa were evaluated under epifluorescence microscope with Ethidium homodimer‐1/peanut agglutinin fluorescein isothiocyanate staining method (EthD‐1/PNA‐FITC). The results show that OE, P4 and a combination of OE/P4 at concentrations used did not affect sperm viability. Heparin significantly (p < 0.001) increased sperm plasma membrane scrambling of OE and P4‐treated spermatozoa. P4 significantly affected the rate of sperm capacitation (p < 0.001) and AR (p < 0.05), but OE expressed membrane‐stabilizing properties (p < 0.05). It can be concluded that in frozen–thawed bovine spermatozoa OE presents plasma membrane stabilizing properties that can be abolished by Hep, but not by P4. Progesterone possesses capacitating and AR‐inducing properties in frozen–thawed bovine spermatozoa that can be alleviated by OE.