julilili42/papers huggingface dataset:
Electroneutral ammonium transport by basolateral rhesus B glycoprotein
2004-07-30

The liver and kidney are important tissues for ammonium (NH 4 + /NH 3 ) metabolism and excretion. The rhesus B glycoprotein (RhBG) is a membrane protein expressed in liver and kidney with similarity to NH 4 + transporters found in microorganisms, plants and animals. In the kidney, RhBG is predominantly localized to basolateral membranes of distal tubule epithelia, including connecting tubules and collecting ducts. These epithelia display mainly electroneutral ammonium transport, in contrast to other tubular sites, where net NH 4 + transport occurs. In accordance with its localization, human RhBG mediates saturable, electroneutral transport of the ammonium analogue methylammonium when heterologously expressed in Xenopus oocytes. Uptake of methylammonium saturates with a K m = 2.6 m m . Methylammonium uptake is inhibited by ammonium and this inhibition saturates with a K i ≈ 3 m m . Electric current measurements and intracellular pH i determinations suggest that RhBG acts as an electroneutral NH 4 + –H + exchanger.
Electrophysiological and molecular characterization of the inward rectifier in juxtaglomerular cells from rat kidney
2004-07-30

Renin, the key element of the renin–angiotensin–aldosterone system, is mainly produced by and stored in the juxtaglomerular cells in the kidney. These cells are situated in the media of the afferent arteriole close to the vessel pole and can transform into smooth muscle cells and vice versa. In this study, the electrophysiological properties and the molecular identity of the K + channels responsible for the resting membrane potential (∼−60 mV) of the juxtaglomerular cells were examined. In order to increase the number of juxtaglomerular cells, afferent arterioles from NaCl‐depleted rats were used, and &gt; 90% of the afferent arterioles were renin positive at the distal end of the arteriole. Whole‐cell and cell‐attached single‐channel patch‐clamp experiments showed that juxtaglomerular cells are endowed with a strongly inwardly rectifying K + channel (Kir). The channel was highly sensitive to inhibition by Ba 2+ (inhibition constant 37 μ m at 0 mV), but relatively insensitive to Cs + and, with 142 m m K + in the pipette, had a single‐channel conductance of 31.5 pS. Immunocytochemical studies showed the presence of Kir2.1 but no signal for Kir2.2 in the media of the afferent arteriole. In PCR analyses using isolated juxtaglomerular cells, the mRNA for Kir2.1 and Kir2.2 was detected. Collectively, the results show that Kir2.1 is the dominant component of the channel. The current carried by these channels plays a decisive role in setting the membrane potential of juxtaglomerular cells.
Studies of orbital parameters and pulse profile of the accreting millisecond pulsar XTE J1807–294
2004-07-30

The accreting millisecond pulsar XTE J1807-294 was observed by XMM-Newton on March 22, 2003 after its discovery on February 21, 2003 by RXTE. The source was detected in its bright phase with an observed average count rate of 33.3 cts/s in the EPIC-pn camera in the 0.5-10 keV energy band (3.7 mCrab). Using the earlier established best-fit orbital period of 40.0741+/-0.0005 minutes from RXTE observations and considering a circular binary orbit as first approximation, we derived a value of 4.8+/-0.1 lt-ms for the projected orbital radius of the binary system and an epoch of the orbital phase of MJD 52720.67415(16). The barycentric mean spin period of the pulsar was derived as 5.2459427+/-0.0000004 ms. The pulsar's spin-pulse profile showed a prominent (1.5 ms FWHM) pulse, with energy and orbital phase dependence in the amplitude and shape. The measured pulsed fraction in four energy bands was found to be 3.1+/-0.2 % (0.5-3.0 keV), 5.4+/-0.4 % (3.0-6.0 keV), 5.1+/-0.7 % (6.0-10.0 keV) and 3.7+/-0.2 % (0.5-10.0 keV), respectively. Studies of spin-profiles with orbital phase and energy showed significant increase in its pulsed fraction during the second observed orbit of the neutron star, gradually declining in the subsequent two orbits, which was associated with sudden but marginal increase in mass accretion. From our investigations of orbital parameters and estimation of other properties of this compact binary system, we conclude that XTE J1807-294 is very likely a candidate for a millisecond radio pulsar.
Evolution of irradiated circumbinary disks
2004-07-30

We study the evolution and emission of circumbinary disks around close\\nclassical T Tauri binary systems. High resolution numerical hydrodynamical\\nsimulations are employed to model a system consisting of a central eccentric\\nbinary star within an irradiated accretion disk. A detailed energy balance\\nincluding viscous heating, radiative cooling and irradiation from the central\\nstar is applied to calculate accurately the emitted spectral energy\\ndistribution. Numerical simulations using two different methods, the previously\\ndeveloped Dual-Grid technique with a finite difference discretization, and the\\nSmoothed Particle Hydrodynamics method are employed to compare the\\nhydrodynamical features and strengthen our conclusions. Physical parameters of\\nthe setup are chosen to model the close systems of DQ Tau and AK Sco. Using the\\nself-consistent models, we are able to fit the observed spectral energy\\ndistributions by constraining parameters such as disk mass, density profile and\\nradial extension for those systems. We find that the incorporation of\\nirradiation effects is necessary to obtain correct disk temperatures.\\n
Intracranial aspergillosis in a non‐immunocompromised patient treated for muscle‐invasive bladder cancer
2004-07-30

Abstract We report a case of intracerebral Aspergillosis in a patient undergoing radical cystectomy for the treatment of muscle‐invasive bladder cancer who did not reveal any deterioration of the immune system. Aspergillus fumigatus is an ubiquitously present, airborne fungus that tends to infect the upper respiratory tract. However, the latter was not observed in the patient presented. Complications in the form of an involvement of the central nervous system are very rarely recognized as a result of an Aspergillus infection and primarily occur in patients who are not immunologically competent. To our knowledge, we present the first case of intracerebral invasive Aspergillosis in an otherwise healthy patient diagnosed with an urological malignancy.
Regional Patterns of Gene Expression in Human and Chimpanzee Brains
2004-08-01

We have analyzed gene expression in various brain regions of humans and chimpanzees. Within both human and chimpanzee individuals, the transcriptomes of the cerebral cortex are very similar to each other and differ more between individuals than among regions within an individual. In contrast, the transcriptomes of the cerebral cortex, the caudate nucleus, and the cerebellum differ substantially from each other. Between humans and chimpanzees, 10% of genes differ in their expression in at least one region of the brain. The majority of these expression differences are shared among all brain regions. Whereas genes encoding proteins involved in signal transduction and cell differentiation differ significantly between brain regions within individuals, no such pattern is seen between the species. However, a subset of genes that show expression differences between humans and chimpanzees are distributed nonrandomly across the genome. Furthermore, genes that show an elevated expression level in humans are statistically significantly enriched in regions that are recently duplicated in humans.
The East Asian Dollar Standard, Fear of Floating, and Original Sin
2004-08-01

Abstract Before the crisis of 1997/98, the East Asian economies—except for Japan but including China—pegged their currencies to the US dollar. To avoid further turmoil, the IMF argues that these currencies should float more freely. However, the authors’ econometric estimations show that the dollar's predominant weight in East Asian currency baskets has returned to its pre‐crisis levels. By 2002, the day‐to‐day volatility of each country's exchange rate against the dollar had again become negligible. Most governments were rapidly accumulating a “war chest” of official dollar reserves, which portends that this exchange rate stabilization will come to extend over months or quarters. From the doctrine of “original sin” applied to emerging‐market economies, the authors argue that this fear of floating is entirely rational from the perspective of each individual country. And their joint pegging to the dollar benefits the East Asian dollar bloc as a whole, although Japan remains an important outlier.
Radiofrequency Ablation: In Vivo Comparison of Four Commercially Available Devices in Pig Livers
2004-08-01

Larger coagulation volumes were obtained with the perfusion and internally cooled cluster devices. More spherical volumes of ablation were achieved with the 12-tine and cluster electrodes. The former proved superior with regard to the short axis perpendicular to the needle shaft. The cluster and nine-tine electrode produced better reproducibility, which is suggestive of improved predictability of the extent of coagulation with these systems.
Solitary Pulmonary Nodules: Dynamic Contrast-enhanced MR Imaging—Perfusion Differences in Malignant and Benign Lesions
2004-08-01

Dynamic MR imaging delineates significant kinetic and morphologic differences in vascularity and perfusion between malignant and benign solitary pulmonary nodules. Washout seems to be highly specific for malignancy.
Deceiving Oneself About Being in Control: Conscious Detection of Changes in Visuomotor Coupling.
2004-08-01

Previous research has demonstrated that compensatory movements for changes in visuomotor coupling often are not consciously detected. But what factors affect the conscious detection of such changes? This issue was addressed in 4 experiments. Participants carried out a drawing task in which the relative velocity between the actual movement and its visual consequences was perturbed. Unconscious compensatory movements and conscious detection rates were simultaneously recorded. There was an invariant relationship between the extent of the change and its conscious detection that was proportional to the initial drawing velocity. This suggests that conscious change detection relies on a system that integrates visual and motor information-as, for instance, suggested by the internal model theory of motor control. Figural discrepancies increased the detection rates, indicating that additional cues for the what system facilitate conscious change detection.
Structural Aspects in the Theory of Probability
2004-08-01

Probability Measures on Metric Spaces The Fourier Transform in a Banach Space The Structure of Infinitely Divisible Probability Measures Harmonic Analysis of Convolution Semigroups Negative Definite Functions and Convolution Semigroups Probabilistic Properties of Convolution Semigroups Hypergroups in Probability Theory Limit Theorems on Locally Compact Abelian Groups.
Average contaminant concentration and mass flow in aquifers from time‐dependent pumping well data: Analytical framework
2004-08-01

Conventional water samples are representative for small subsurface volumes relative to the scale of many natural (geological) heterogeneities. We present an analytical framework for estimation of representative field‐scale average concentrations and mass flows on the basis of much larger sampling volumes that are obtained through so‐called integral pumping tests. The contaminant concentration is then measured as a function of time in a pumping well and used for estimation of the conditions in the aquifer prior to (and after) pumping, increasing the observation scale to the size of the well capture zone. This method complements (and provides an alternative to) conventional monitoring grids, where mass flow and concentration may be misinterpreted or plumes even missed because of problems related to grid spacing. The (not measured) initial spatial concentration distribution and the time‐dependent concentration measured at the well are related through a Volterra integral equation of the first kind. For limiting cases of short and long dimensionless pumping duration, two closed form analytical solutions are given, from which the mass flow and average concentration can be evaluated. Furthermore, a new solution for evaluating integral pumping tests of any duration is provided and used for investigating the applicability of the simple, analytical closed form solutions for interpreting test results from seven large‐scale contaminated sites in Europe.
Classification and Correlation of St. John's Wort Extracts by Nuclear Magnetic Resonance Spectroscopy, Multivariate Data Analysis and Pharmacological Activity
2004-08-01

The use of proton NMR spectroscopy allows the analysis of complex multi-component mixtures such as plant extracts by simultaneous quantification of all proton-bearing compounds and consequently all relevant substance classes. Since the spectra obtained are too complicated to be analysed visually, the classification of spectra was carried out using multivariate statistical methods. The spectroscopic data of various extracts of St. John's wort (Hypericum perforatum) samples derived from 4 different accessions extracted with 6 distinct solvents were chemometrically evaluated and calibrated using the partial least square (PLS) algorithm. In a first approach, we found a consistent correlation for the spectroscopic pattern of the extracts and the corresponding IC (50) values derived from non-selective binding to opioid receptors. Consequently, the multivariate data analysis was used to predict the pharmacological efficacy of further St. John's wort extracts on the basis of their proton NMR spectra. In a second approach a PLS 2 model was used to predict the biological activity for eight St. John's wort extracts based on two pharmacological data sets: (i) non-selective binding to opioid receptors and (ii) antagonist effect at corticotrophin-releasing factor type 1 (CRF (1)) receptors. The PLS 2 model confirmed the useful application of the presented approach to assess the quality of medicinal herbs and extracts by spectroscopic analysis derived from bioactivity-related quality parameters.
ANTIBODIES TO RIFIN: A COMPONENT OF NATURALLY ACQUIRED RESPONSES TO PLASMODIUM FALCIPARUM VARIANT SURFACE ANTIGENS ON INFECTED ERYTHROCYTES
2004-08-01

We used a pool of recombinant rifin proteins to pre-adsorb antibodies to rifin in the plasma of semi-immune African (Gabonese) adults and showed that this results in a reduction in the level of IgG antibody reactivity to variant surface antigens (VSA) measured in a standardized flow cytometric assay with a panel of heterologous parasite isolates. The same methods demonstrated a similar but less-marked contribution of antibodies to the duffy binding-like 1α (DBL-1α ) domain to the overall anti-VSA response. Thus, we conclude that both antibodies to rifin and, to a lesser extent, antibodies directed to conserved regions of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) DBL-1α domain contribute to the overall antibody response to VSA. We also assessed the associations between these different antibody responses in a cohort of Gabonese children. We found marked differences related to the childrens’ history of presentation with either mild or severe malaria, but no consistent pattern that would indicate a specific role or influence of antibody responses to rifin.
Evaluation of balhimycin as a chiral selector for enantioresolution by capillary electrophoresis
2004-08-01

Abstract The glycopeptide antibiotic balhimycin and its haloanalogue bromobalhimycin were evaluated as chiral selectors for enantioresolution by capillary electrophoresis. In order (i) to eliminate the adsorption of the glycopeptide antibiotics on the capillary wall, (ii) to shorten the separation time and (iii) to improve the detection sensitivity, a combined approach of the dynamic surface coating technique, the co‐electroosmotic flow electrophoresis technique and the partial filling technique was employed for the enantioresolution of 16 acidic racemates. The effect of experimental parameters (plug length of the partial filling solution containing the chiral selector, selector concentration and buffer pH) on enantiorecognition was investigated. Furthermore, the enantiorecognition ability imparted by balhimycin, bromobalhimycin and vancomycin were compared. For most tested compounds, the highest enantiorecognition was obtained with balhimycin as chiral selector. Only in the case of the enantioresolution of tiaprofenic acid, vancomycin showed a superior enantiorecognition.
Stanna‐closo‐dodecaborate: A New Ligand in Coordination Chemistry
2004-08-01

Abstract Most of the divalent compounds of tin have a lone pair and hence can act as donors. In tin‐transition metal chemistry neutral molecules as well as anions have been studied as ligands. This research report summarizes recent research on coordination compounds with a closo ‐heteroborate cage compound stanna‐ closo ‐dodecaborate [SnB 11 H 11 ] 2− . The syntheses of the first coordination compounds and studies on the ligand abilities of this tin borate are discussed in this article.
Oncogene Suppression by Small Interfering RNAs
2004-08-01

Almost all human cancers have accumulated multiple genetic lesions including oncogenes. It is often unknown whether an oncogene is continuously required for tumorigenesis. Furthermore, it is very difficult to target an essential oncogene with drugs without affecting the corresponding nonmutated protooncogene or related factors. The recent discovery of RNA interference and the application of small interfering RNAs in mammalian cell culture provide now tools to examine the role of oncogenes in tumor development. Furthermore, oncogene-specific siRNAs may become promising candidates for more cancer-specific therapeutic approaches. This review discusses the potential and the limitations of oncogene-targeting siRNAs and describes examples for the application of siRNAs in the functional analysis of oncogenes.
Hand development and sequence of ossification in the forelimb of the European shrew Crocidura russula (Soricidae) and comparisons across therian mammals
2004-08-01

Abstract Hand development in the European shrew Crocidura russula is described, based on the examination of a cleared and double‐stained ontogenetic series and histological sections of a c . 20‐day‐old embryo and a neonate. In the embryo all carpal elements are still mesenchymal condensations, and there are three more elements than in the adult stage: the ‘lunatum’, which fuses with the scaphoid around birth; a centrale, which either fuses with another carpal element or just disappears later in ontogeny; and the anlage of an element that later fuses with the radius. Carpal arrangement in the neonate and the adult is the same. In order to compare the relative timing of the onset of ossification in forelimb bones in C. russula with that of other therians, we built up two matrices of events based on two sets of data and used the event‐pair method. In the first analysis, ossification of forelimb elements in general was examined, including that of the humerus, radius, ulna, the first carpal and metacarpal to ossify, and the phalanges of the third digit. The second analysis included each carpal, humerus, radius, ulna, the first metacarpal and the first phalanx to ossify. Some characters (= event–pairs) provide synapomorphies for some clades examined. There have been some shifts in the timing of ossification apparently not caused by ecological and/or environmental influences. In two species ( Oryctolagus and Myotis ), there is a tendency to start the ossification of the carpals relatively earlier than in all other species examined, the sauropsid outgroups included.
Preoperative Marking of Musculoskeletal Tumors Guided by Magnetic Resonance Imaging
2004-08-01

Preoperative coil-marking guided by magnetic resonance imaging for exact delineation of a musculoskeletal tumor is technically feasible and can readily demonstrate the full extent of the tumor. Use of magnetic resonance fluoroscopy reduces the time needed for the intervention. We recommend the coil-marking technique.
Uncommon Case of a Foreign Body Ingestion with Consecutive Small-Bowel Obstruction in a Child
2004-08-01

A 12-year-old boy with Lennox syndrome presented with an acute abdomen and a history of progressive abdominal pain and vomiting over 3 weeks. The uncommon finding in this case was a foreign body detected in a lower loop of the jejunum causing radiological and clinical signs of jejunitis/ileitis. The foreign body had to be removed surgically and turned out to be a hard (originally soft) plastic part of a towel rack.
Ring Size Influence on the Cyclocondensation Mode of GABA – Nitrile Imine Adducts
2004-08-01

Abstract γ -Aminobutyric acid (GABA) adds onto nitrile imine 1,3-dipolar species (generated in situ from their N-arylhydrazonoyl chloride precursors 1a-c ) to deliver the corresponding acyclic amidrazone adducts 10a-c. In the presence of 1,1’-carbonyldiimidazole, the latter adducts undergo cyclocondensation involving the activated carboxyl and the amidrazone-CH 2 NH groups to afford the respective N-[1-(arylhydrazono)-2-oxopropan-1-yl] pyrrolidin-2-ones (11a-c). The constitution of 10 and 11 is evidenced from analytical and spectral (IR , MS and NMR) data.
[Taking responsibility for one's own health. Possibilities and limits using the example of malignant melanoma].
2004-08-01

Because of the persistent shortage of health care resources, scientists and politicians are discussing ways to increase the patients' personal responsibility for their own health. Based on a philosophical analysis of the concept of responsibility, this article tries to assess strengths and limits of a personal responsibility for health, illustrated by the prevention of cutaneous melanoma. On the one hand, individuals bear prospective responsibility for their health status by adopting a healthy lifestyle and participating in prevention programs. On the other hand, individuals can--retrospectively--be held responsible for those conditions that result from the voluntary choice of health risks. Considering the tremendous practical and ethical problems associated with retrospective responsibility, prevention and public health policies should emphasize prospective personal responsibility for health.
Rubidium hydroxide polyethylene glycol crown ether in the conservation of old master paintings*
2004-08-01

The development of new, gentler methods for the conservation of Old Master paintings, with an emphasis on the removal or thinning of deteriorated varnish, is of high priority. In the course of the deterioration process, oxidative attacks lead to progressive formation of carboxylic acid groups, while many ester bondings are expected to be weakened. A stable RbOH polyethylene glycol complex was a promising tool to react with these moieties and to successfully break down the polymeric varnish layer. The remnants were easily wiped off mechanically. Control studies employing 86 RbOH and 14 C polyacrylate showed the complete absence of residual cleansing components on the paint surface.
22 Final results of two randomized adjuvant trials of DeCOG
2004-08-01

Garbe, C.; Hauschild, A.; Linse, R.; Dummer, R.; Kapp, A.; Ulrich, J.; Schubert, L.; Stadler, R.; Kaufmann, R.; Reinhold, U.; Meigel, W.; Mauch, C.; Bahmer, F.; Elsner, P.; Koch, J.; Stolz, W.; Kohl, P.; Seebacher, C. Author Information