julilili42/papers huggingface dataset:
Geographical Slant Facilitates Navigation and Orientation in Virtual Environments
2004-06-01

Theoretical considerations and earlier experimental findings indicate that traveling over slanted terrain can lead to an enrichment of the perceived spatial cues relevant for navigation. We investigated the proposed facilitation of a uniformly slanted environment on navigation and orientation performance with a virtual environment presented on a large 180° screen, using as material a virtual town with eight places and twenty-four landmarks. In the control condition, this town was placed on a flat surface; in the two experimental conditions, the town was placed on a slope with a uniform angle of 4°. Pedaling on a bicycle simulator, participants first explored the environment, then solved navigation tasks, pointed from various positions to distant landmarks, judged the relative elevation of pairs of distant landmarks from memory, and finally drew a sketch map of the environment. In comparison to the control condition, the number of navigation errors was significantly lower in the slanted conditions, and the deviations in the pointings to distant landmarks were massively reduced. Participants from the slant conditions also showed good knowledge of the relative elevations of pairs of distant locations. However, no differences in map-drawing quality were found. The results lend additional support to the proposition that our spatial knowledge, which is used in navigation and orientation, contains vertical information.
The effect of HAMP domains on class IIIb adenylyl cyclases from Mycobacterium tuberculosis
2004-06-01

The genes Rv1318c , Rv1319c , Rv1320c and Rv3645 of Mycobacterium tuberculosis are predicted to code for four out of 15 adenylyl cyclases in this pathogen. The proteins consist of a membrane anchor, a HAMP region and a class IIIb adenylyl cyclase catalytic domain. Expression and purification of the isolated catalytic domains yielded adenylyl cyclase activity for all four recombinant proteins. Expression of the HAMP region fused to the catalytic domain increased activity in Rv3645 21‐fold and slightly reduced activity in Rv1319c by 70%, demonstrating isoform‐specific effects of the HAMP domains. Point mutations were generated to remove predicted hydrophobic protein surfaces in the HAMP domains. The mutations further stimulated activity in Rv3645 eight‐fold, whereas the effect on Rv1319c was marginal. Thus HAMP domains can act directly as modulators of adenylyl cyclase activity. The modulatory properties of the HAMP domains were confirmed by swapping them between Rv1319c and Rv3645. The data indicate that in the mycobacterial adenylyl cyclases the HAMP domains do not display a uniform regulatory input but instead each form a distinct signaling unit with its adjoining catalytic domain.
Increased high-frequency heart rate variability during insulin-induced hypoglycaemia in healthy humans
2004-06-01

Despite causing sympathetic activation, prolonged hypoglycaemia produces little change in HR (heart rate) in healthy young adults. One explanation could be concurrent parasympathetic activation, resulting in unchanged net effects of autonomic influences. In the present study, hypoglycaemic (2.7 mmol/l) and normoglycaemic (4.7 mmol/l) hyperinsulinaemic clamp studies were performed after normoglycaemic baseline clamp periods with 15 healthy volunteers (seven male; mean age, 27 years) on two occasions in a randomized single-blind cross-over design. Non-invasive indices of cardiac autonomic activity and hormones were measured at baseline and 1 h after the beginning of hypoglycaemia or control normoglycaemia. Plasma insulin levels and mean HR were similar during both conditions. During hypoglycaemia, there was a 485% increase in plasma adrenaline (epinephrine). A shortening of the pre-ejection period by 45% suggested strong sympathetic cardiac activation. High-frequency (0.15–0.45 Hz) HRV (HR variability) increased, indicating a concomitant increase in parasympathetic tone. Thus, during hypoglycaemia-induced sympathetic cardiac activation in healthy adults, parasympathetic mechanisms are involved in stabilizing mean HR.
Minimally invasive direct coronary artery bypass grafting: a systematic review.
2004-06-01

Clinical outcomes and immediate graft patency after MIDCAB are acceptable. However, long-term follow-up results and further randomized prospective clinical trials comparing this new technique with standard revascularization procedures are needed.
Identification of C-Met Oncogene as a Broadly Expressed Tumor-Associated Antigen Recognized by Cytotoxic T-Lymphocytes
2004-06-01

Abstract Purpose: C-Met proto-oncogene is a receptor tyrosine kinase that mediates the oncogenic activities of the hepatocyte growth factor. Using a DNA chip analysis of tumor samples from patients with renal cell carcinoma and sequencing of peptides bound to the HLA-A*0201 molecules on tumor cells a peptide derived from the c-Met protein was identified recently. Experimental Design: We used this novel HLA-A*0201 peptide for the induction of specific CTLs to analyze the presentation of this epitope by malignant cells. Results: The induced CTL efficiently lysed target cells pulsed with the cognate peptide, as well as HLA-A*0201-matched tumor cell lines in an antigen-specific and HLA-restricted manner. Furthermore, the induced c-Met-specific CTLs recognized autologous dendritic cells (DCs) pulsed with the peptide or transfected with whole-tumor mRNA purified from c-Met-expressing cell lines. We next induced c-Met-specific CTLs using peripheral blood mononuclear cells and DC from an HLA-A*0201-positive patient with plasma cell leukemia to determine the recognition of primary autologous malignant cells. These CTLs lysed malignant plasma cells while sparing nonmalignant B- and T-lymphocytes, monocytes, and DCs. Conclusion: Our results demonstrate that c-Met oncogene is a novel tumor rejection antigen recognized by CTL and expressed on a broad variety of epithelial and hematopoietic malignant cells.
Immune Deviation Strategies in the Therapy of Psoriasis
2004-06-01

The experience with biologicals in currently available animal models suggest that inflammatory autoimmune disease depend on IFN-gamma-producing T helper (Th) cells. Deletion of T cells improves most of these autoimmune diseases but bears the risks of general immunosuppression. Alternatively, selective deviation of the inflammatory, disease-inducing Th cells into an anti-inflammatory Th cell phenotype may be a promising strategy to treat inflammatory autoimmune diseases, such as psoriasis, rheumatoid arthritis, multiple sclerosis or autoimmune diabetes. The common feature of these organ-specific autoimmune diseases is the close association with IFN-gamma-producing Th1 cells, which recognize organ-specific antigens and orchestrate the cells and mediators that ultimately cause the tissue damage. Even though the autoantigens recognized in psoriasis remain enigmatic, it has been the first Th1-mediated autoimmune disease successfully treated in humans by immune deviation. The basis of such an immune intervention therapy has been established in experimental mice with model diseases of multiple sclerosis, rheumatoid arthritis or autoimmune diabetes. In all these autoimmune diseases clinical improvement was associated with the skewing of IFN-gamma producing autoantigen-specific Th1 cells into an IL-4 dominated Th2 phenotype. Such Th2 cells are still reactive to the autoantigen but provide a different cytokine pattern. The most powerful cytokines capable of inducing anti-inflammatory Th2 cells are IL-4 itself or IL-11. Interestingly, another agent that has been used for decades in the therapy of psoriasis in some European countries, fumaric acid esters (FAE), seems also to induce immune deviation. This review focuses on the potential immune deviating strategies based on the use of IL-4, IL-11 or FAE in the therapy of psoriasis, the effects of these agents on the immune system, potential risks and future perspectives for therapeutic intervention by immune deviation replacing immunosuppression.
A trace fossil assemblage from fluvial Old Red deposits (Wood Bay Formation; Lower to Middle Devonian) of NW‐Spitsbergen, Svalbard
2004-06-01

From the fluvial Old Red Sandstone (ORS) of the Lower to Middle Devonian Wood Bay Formation (NW‐Spitsbergen), a diverse trace fossil assemblage, including two new ichnotaxa, is described: Svalbardichnus trilobus igen. n., isp. n. is interpreted as the three‐lobed resting trace of an early phyllocarid crustacean (Rhinocarididae). Cruziana polaris isp. n. yields morphological details that point towards a trilobite origin. This occurence of presumably marine trace makers in a fluvial red bed sequence raises the question of whether we are dealing with marine ingressions that are not sedimentologically expressed, with homeomorphy, or with an adaptation of marine groups to non‐marine environments.
Does Social Desirability Inflate the Correlation between Self-Esteem and Anxiety?
2004-06-01

Although several authors concluded that self-esteem is negatively related to anxiety, it is an open question what role social desirability plays in this relation. In a sample of 61 German students, the correlation between self-esteem and anxiety was significantly reduced from – .59 to – .51 when social desirability was partialed out. Thus, social desirability does seem to inflate the correlation between self-esteem and anxiety when both constructs are measured with self-reports. Yet, this effect of social desirability appears so small that it is probably negligible for most research purposes.
Identification of an SSX-2 Epitope Presented by Dendritic Cells to Circulating Autologous CD4+ T Cells
2004-06-01

Abstract Accumulating evidence supports the requirement for both tumor-specific CD8+ and CD4+ T cell responses for efficient tumor rejection to occur. Because of its expression in different tumor types, the cancer/testis Ag encoded by the synovial sarcoma X breakpoint 2 (SSX-2) gene is among the most relevant candidates for the development of generic cancer vaccines. The immunogenicity of SSX-2 has been previously corroborated by detection of specific humoral and CD8+ T cell responses in cancer patients. In this study we report identification of the first CD4+ T cell epitope encoded by SSX-2. The identified epitope mapped to the 19–34 region of the protein and was recognized by CD4+ T cells from an Ag-expressing melanoma patient in association with HLA-DPB1*0101. The absence of detectable response in healthy donors and other patients suggests that SSX-2-specific CD4+ T cells in the responder patient had been previously expanded in vivo in response to the autologous tumor. The epitope did not appear to be presented on the surface of tumor cells at levels sufficient to allow direct recognition. In contrast, it was efficiently presented by autologous dendritic cells, supporting the concept that processing by professional APC is the main pathway through which the CD4+ T cell immunoresponse to tumor Ags occurs in vivo.
Synthesis of the 8‐Hydroxy Acid of Jasplakinolide
2004-06-01

Abstract The protected ω‐hydroxy acid 4b contained in the depsipeptide jasplakinolide ( 1 ) was prepared in a sequence of 13 steps from the silylated 3‐hydroxy ester 6 . By chain extension 6 was converted to the allyl alcohol 10 . A subsequent asymmetric cyclopropanation of the allylic alcohol 10 using the Charette method provided the hydroxymethylcyclopropane 12 with excellent diastereoselectivity. This cyclopropanation was used to establish the methyl‐bearing stereocenter at C‐6 of the hydroxy acid 4 by reductive ring cleavage of the (iodomethyl)cyclopropane 14 . The alkene 15 was used for a cross alkene metathesis reaction with 2‐methylacrylate 20 providing the enoate 19 . The derived allylic iodide 24 served as an electrophile in the final Evans alkylation step to give the ω‐hydroxy acid derivative 26 .
Nuclear deformation and the double-beta decay
2004-06-01

The effect of deformation on the two-neutrino double-beta decay (2νββ decay) for ground-state transition 76Ge → 76Se is studied in the framework of the deformed QRPA with separable Gamow-Teller residual interaction. A new suppression mechanism of the 2νββ-decay matrix element based on the difference in deformations of the initial and final nuclei is reported. An advantage of this suppression mechanism in comparison with that associated with ground-state correlations is that it allows a simultaneous description of the single-β and the 2νββ decay.
Engineering Anticancer T Cells for Extended Functional Longevity
2004-06-01

A bstract : Like other somatic cells, human T lymphocytes have a finite replicative capacity in vitro , and, by implication and consistent with the limited data available, in vivo as well. An accumulation of dysfunctional T cells may be detrimental under conditions of chronic antigenic stress (chronic infection, cancer, autoimmunity). Using T cells from young donors to model the process of T cell clonal expansion in vitro under these conditions reveals age‐associated increasing levels of oxidative DNA damage and microsatellite instability (MSI), coupled with decreasing DNA repair capacity, telomerase induction and telomere length, decreased levels of expression of the T cell costimulator CD28 and consequently reduced secretion of the T cell growth factor interleukin‐2 (IL‐2). However, data from similar experiments using T cell clones (TCCs) derived from extremely healthy very elderly donors (“successfully aged”) indicate that DNA repair is better maintained, MSI less prevalent, and (already short) telomere lengths are maintained. Nonetheless, oxidative DNA damage is seen to the same extent, and clonal longevity is also similar in these clones. DNA damage levels are reduced by culture in 5% oxygen, but longevity is not improved. This may be because of the requirement for intermittent reactivation via receptor pathways dependent on free radical production in T cells. These recent findings from our international immunosenescence research consortium suggest that strategies other than telomere maintenance, better protection against free radicals, or improved DNA repair will be required for functional longevity extension of human TCCs. To obtain sufficient cells for adoptive immunotherapy of cancer, alternative avenues need exploration; currently, these include enforced expression of certain heat shock proteins and proteasome components, and interference with the expression of negative regulatory receptors expressed by T cells.
Brain Natriuretic Peptide (BNP) in Patients Undergoing Coronary Artery Bypass Grafting
2004-06-01

Postoperative peak of BNP after 24 h does not reflect a state of acute perioperative heart failure or myocardial damage. These results suggest that the gene expression, metabolism and biological activity of BNP may be altered after extracorporeal circulation. Further studies are warranted to reveal the actual triggers for BNP increase early after CABG.
Novel Retractor for Endoscopic and Microsurgical Spinal Interventions
2004-06-01

Retractors play an important role in surgery, especially using endoscopic techniques like microendoscopic discectomy. As a consequence of the minimally invasive approach the working space is frequently very restricted. All currently available systems still use tubular retractors with limitations regarding flexibility, stability and accessible working space. This paper discusses the technical aspects of a newly designed circular retractor system for endoscopic and microsurgical spinal interventions (SpineGate) and presents first clinical results in a series of 20 consecutive patients. The autoclavable system consists of a circular base plate and several valves varying in length. The variable fixation of the valves from different directions within the 360 degrees geometry of the base plate allows a continuously adjustable working space, depending on the individual anatomy. An additional fixation device is not necessary. The retractor is suitable for microendoscopic and microsurgical techniques. It is easy and safe to handle. The retractor system was successfully used in all cases without complications or instrumental malfunctions. All patients experienced good to excellent relief of their preoperative symptoms.
Elimination of Linezolid by an in vitro Extracorporeal Circuit Model
2004-06-01

Linezolid is an oxazolidinone antibiotic with activity against important grampositive aerobic bacteria, including nosocomial pathogens. It is not known whether dosage adjustments are necessary in patients treated with continuous renal replacement therapies. This in vitro study was conducted to investigate the elimination of linezolid in an in vitro continuous hemo(dia)filtration model using different filter materials (polysulfone, polyacrylonitrile, polyamide), surface areas, and different modes of renal replacement therapies. Linezolid was measured using HPLC with UV-detection. No adsorption of linezolid to any of the tested membranes was detected. Recovery of linezolid in the ultrafiltrate was 98.2 ± 10.5% in the filtration mode. During dialysis, recovery was significantly less (87.6 ± 16.1%; p = 0.02). Linezolid elimination was not altered by filter size, when polysulfone filters with surface areas of 0.7 m 2 and 1.3 m 2 were tested. In conclusion, the dosage recommendations for linezolid are independent of the filter materials. However, the elimination is significantly higher during hemofiltration compared to dialysis.
A revenue-equivalence theorem for electricity auctions
2004-06-01

The purpose of this paper is to analyse the real-time trading of electricity. We address a model for an auction-like trading which captures key features of real-world electricity markets. Our main result establishes that, under certain conditions, the expected total payment for electricity is independent of the particular auction type. This result is analogous to the revenue-equivalence theorem known for classical auctions and could contribute to an improved understanding of different electricity market designs and their comparison.
Adiponectin in Youth
2004-06-01

Bacha et al. (1) studied the relationship of serum adiponectin concentrations with hepatic and peripheral insulin sensitivity, body fat distribution, and components of the metabolic syndrome in adolescents. In addition, they reported a negative association between fasting serum proinsulin and the fasting serum proinsulin-to-insulin ratio with adiponectin levels, which was independent of adiposity. They conclude that hypoadiponectinemia may be a marker of β-cell dysfunction. These data are novel and appear to be suggestive of a primary role of adiponectin in β-cell function. We consider this hypothesis to ...
Characterization of glycine N-methyltransferase from rabbit liver
2004-06-01

The enzymatic properties of glycine N-methyltransferase from rabbit liver and the effects of endogenous adenosine nucleosides, nucleotides and methyltransferase inhibitors were investigated using a photometrical assay to detect sarcosine with o-dianisidine as a dye. After isolation and purification the denatured enzyme showed a two-banded pattern by SDS–PAGE. The enzyme was highly specific for its substrates with a pH-optimum at pH 8.6. Glycine N-methyltransferase exhibits Michaelis-Menten kinetics for its substrates, S-adenosylmethionine and glycine, respectively. The apparent K m and V max values were determined for both the substrates, the other substrate being present at saturating concentrations. The enzyme was strongly inhibited in the presence of S-adenosylhomocysteine, 3-deazaadenosine, and 5′-S-isobutylthio-5′-deoxyadenosine. All other inhibitors investigated, adenosine, 2′-deoxyadenosine, aciclovir, and 5′-N-ethylcarboxamidoadenosine were poor inhibitors of the methylation rection. Adenine nucleotides and vidarabin were without effect on the enzymatic activity. Based on the kinetic data glycine N-methyltransferase from rabbit liver exhibits appreciable activity at physiological S-adenosylmethionine and S-adenosylhomocysteine levels.Key words: glycine N-methyltransferase, S-adenosylhomocysteine, S-adenosylmethionine, sarcosine oxidase, peroxidase.
Crystal structure of pentabismuth heptaoxide nitrate, Bi5O7NO3
2004-06-01

Abstract Bi 5 NO 10 , monoclinic, P 12 1 / c 1 (no. 14), a = 8.5846(6) Å, b = 23.385(2) Å, c = 5.5422(4) Å, β = 108.103(8)°, V = 1057.5 Å 3 , Z = 4, R gt (F) = 0.029, wR ref (F 2 ) = 0.074, T = 210 K.
Crystal structure of [9,22-(bisbutyloxy)hemiporphyrazinato]nickel(II), C34H30N8O2Ni
2004-06-01

Abstract C 34 H 30 N 8 NiO 2 , monoclinic, P 12 1 / n 1 (no. 14), a = 14.048(4) Å, b = 4.7256(1) Å, c = 21.491(6) Å, β = 99.10(1)°, V = 1408.7 Å 3 , Z = 2, R gt (F) = 0.054, wR ref (F) = 0.059, T = 293 K.
Reconstructive urology
2004-06-01

Objective: To describe the topography of the perineal nerves from their pudendal origin to their course into the male genitalia, with specific attention on the course of the perineal nerve along the ventral penis, including branches into bulbospongiosus muscle and corpus spongiosum.Materials and Methods: The study comprised 18 normal human fetal penile specimens at 17.5 -38 weeks of gestation (determined by fetal heel-to-toe length).Specimens were fixed in formalin, embedded in paraffin wax and serially sectioned at 6 micro m.The penile specimens contained the whole penis from the glans to the crural bodies, beneath the pubic arch and the perineum up to the anal verge.Immunocytochemistry was assessed on selected sections with antibodies against the neuronal markers S-100 and nitric oxide synthase (nNOS).Three-dimensional computer reconstruction of serial sections allowed an in-depth analysis of the neuroanatomy of the fetal penis, perineum and surrounding structures.Results: After the pudendal nerve leaves the pudendal canal it gives rise to the perineal nerve branches in the ischiorectal fossa.Perineal nerves travel alongside the ischiocavernous and bulbospongiosus muscles and before reaching the latter, nerve branches course into the bulbospongiosus muscle.During its pathway within this muscle, fine nerve fibres course into the corpus spongiosum by piercing through the junction of the muscle.At the penoscrotal area, the perineal nerves give branches to the scrotum, funnelling into the interscrotal septum.Perineal nerves continue their pathway over the ventral side of penis covering the ventral surface of corpus spongiosum.Branches of the dorsal nerve of the penis at the junction of corpus cavernosum and corpus spongiosum assemble into a network with the perineal nerves.All perineal nerves from their main trunk at the ischiorectal fossa until their interaction with dorsal nerve of penis at the base of penis were nNOS negative.After the interaction with the dorsal nerve of penis, they become nNOS positive.Conclusion: Integrating neuroanatomical knowledge about the perineal nerves and their communication with the dorsal nerve of penis should facilitate a strategic approach to reconstructive procedures on the penis.Special care should be taken at the junction between the corpora cavernosa and spongiosa, where the dorsal nerve joins the perineal nerve, and at the proximal bulbospongiosus muscle, thereby protecting the fine nerves piercing into the cavernosa spongiosa.