julilili42/papers huggingface dataset:
Contribution of Disulfide Bonds and Calcium to Molluscan Hemocyanin Stability
2004-04-01

Disulfide bonds and calcium ions contribute significantly to the stability of the hemocyanin from the mollusc Rapana thomasiana grosse (gastropod). An extremely powerful protective effect of Ca 2+ at a concentration of 100 mᴍ (100% protection) against the destructive effect of reductants like dithiothreitol was observed. This is important for the practical application of molluscan hemocyanins in experimental biochemistry, immunology and medicine. The reduction of the disulfide bonds in the Rapana hemocyanin leads to a 20% decrease of the α-helical structure. The S-S bonds contribute significantly to the free energy of stabilization in water increasing ⊿G D H 2 O by 6.9 kJ mol -1 . The data are related to the X-ray model of the Rapana hemocyanin functional unit RtH2e. The results of this study can be of common validity for related respiratory proteins because the cysteine residues are conserved in all sequences of molluscan hemocyanins published so far.
Eurhopalothrix depressasp. n. (Hymenoptera: Formicidae) from Southern Brazil with a Key to the Neotropical Taxa of the Genus
2004-04-01

Eurhopalothrix depressa sp. n. is described from Southern Brazil. The species belongs to the bolaui group characterised by well developed propodeal teeth and large specialized clavate hairs on the body. It can be distinguished from all other neotropical Eurhopalothrix species by a distinct ridge dividing the head into a lower anterior and a higher posterior part and by the reduced number of 16 specialised hairs on the head. A key to all New World species of Eurhopalothrix is added.
On the Complexity of RSRL
2004-04-01

In this paper we present a computability and a complexity result on Relational Speciate Reentrant Logic (RSRL). RSRL is a description logic designed to formalise the linguistic framework and theory Head-Driven Phrase Structure Grammar. We show here that given an RSRL-formula and a finite RSRL-interpretation it is in general not decidable if the formula is true in the given interpretation by reduction to Post Correspondence Problems. For so-called chainless RSRL, a semantically weaker version in which the expressive power of RSRL is significantly reduced, we show that if a class of finite structures is definable in chainless RSRL it is decidable by a Turing machine polynomially time bounded in the size of the input structures.
EMERGENCY DONOR HEART PROTECTION: APPLICATION OF THE PORT ACCESS CATHETER TECHNIQUE USING A PIG HEART TRANSPLANTATION MODEL1
2004-04-01

In situ perfusion may be suitable for cardiac transplants when donor deterioration requires urgent organ preservation. Catheters can be placed at bedside and modified to achieve multi-organ protection through additional perfusion of the abdominal aorta.
061 Predictors of Poor Outcome in S. Aureus Wound Infection
2004-04-01

Objectives : Staphylococcus aureus is the most common bacterium cultured from infected wounds. We hypothesized that diabetes mellitus (DM) and/or peripheral arterial disease would be patient predictors of severe outcomes, defined as amputation, sepsis, or death, and infections caused by resistant strains would be bacterial predictors of severe outcomes. Methods : With IRB approval, 50 S. aureus strains (45 wound, 5 central line) were isolated during routine clinical care. Investigations included antibiotic resistance (&gt;5 mcg/ml), and PCR for STAR elements. Chart review included wound type, location, relevant comorbidities, antibiotic resistance, and outcome. Results : Outcome n (% of outcome total ) Severe All others Total Diabetic 7 (70) 6 (17) 13 (29) Non‐diabetic 3 (30) 29 (83) 32 (71) MRSA STAR groups 2 (20) 8 (23) 10 (22) All other STAR 8 (80) 27 (77) 35 (78) MRSA 4 (40) 8 (23) 12 (27) MSSA 6 (60) 27 (77) 33 (73) Total patients 10 (22) 35 (78) 45 No non‐DM patient with arterial disease (n = 6) had a poor outcome. Conclusions : The strongest predictor of outcome was the presence of DM. Patients with severe outcomes were slightly more likely to have MRSA infection, although only 33% of patients with MRSA had severe outcomes. Although STAR/ arsRBC groups have been shown previously to predict antibiotic resistance, in this collection there was no correlation between these molecular markers and outcome. This study shows that the strongest predictor of clinical outcome in wound infection is patient‐dependent, while bacterial factors appear to play a lesser role.
Ubiquitylation of synphilin-1 and α-synuclein by SIAH and its presence in cellular inclusions and Lewy bodies imply a role in Parkinson's disease
2004-04-02

Parkinson's disease (PD) is a neurodegenerative disease characterized by Lewy body formation and death of dopaminergic neurons. Mutations in α-synuclein and parkin cause familial forms of PD. Synphilin-1 was shown to interact with α-synuclein and to promote the formation of cytosolic inclusions. We now report that synphilin-1 interacts with the E3 ubiquitin-ligases SIAH-1 and SIAH-2. SIAH proteins ubiquitylate synphilin-1 both in vitro and in vivo , promoting its degradation by the ubiquitin–proteasome system. Inability of the proteasome to degrade synphilin-1/SIAH complex leads to a robust formation of ubiquitylated cytosolic inclusions. Ubiquitylation is required for inclusion formation, because a catalytically inactive mutant of SIAH-1, which still binds to synphilin-1, fails to promote inclusions. Like synphilin-1, α-synuclein associates with SIAH in intact cells, but the interaction with SIAH-2 was much stronger that with SIAH-1. In vitro experiments show that SIAH-2 monoubiquitylates α-synuclein. Further evidence that SIAH proteins may play a role in inclusion formation comes from the demonstration of SIAH immunoreactivity in Lewy bodies of PD patients.
Immunotherapy and immunoselection – tumour escape as the final hurdle
2004-04-07

Tumours are immunogenic and are commonly infiltrated by anti‐cancer effector cells. Why, then, are they not completely rejected by the host? Unfortunately, tumours are Darwinian paragons, winning the battle against the forces of natural immune selection. Some of the latter can even act as double‐edged swords, actually being subverted to become pro‐tumorigenic. Prevention or reversal of tumour escape from the immune response therefore offers the possibility of reconstituting effective anti‐tumour immunity and remains the major challenge for 21st century tumour immunology.
Stress gene (hsp70) sequences and quantitative expression inMilnesium tardigradum(Tardigrada) during active and cryptobiotic stages
2004-04-09

SUMMARY The eutardigrade Milnesium tardigradum can undergo cryptobiosis,i.e. entry into a reversible ametabolic stage induced by dehydration, cooling and, probably, osmotic and anoxic stress. For the first time in tardigrades,we described partial sequences of three heat-shock protein (hsp70family) genes and examined gene expression on the way from an active to a cryptobiotic and back to an active stage again. Results showed different patterns of gene expression in the hsp70 isoforms. All three isoforms seem to be true heat-shock proteins since transcription could be clearly enhanced by temperature elevation. Isoform 1 and, at a lower level, isoform 3 do not seem to have a specific function for cryptobiosis. By contrast,transcription of isoform 2 is significantly induced in the transitional stage between the active and the cryptobiotic stage, resulting in a comparatively high mRNA copy number also during cryptobiosis. This pattern of induction implies that isoform 2 is the most relevant hsp70 gene for M. tardigradum individuals entering the cryptobiotic stage.
3-(4-Acetylphenyl)-1-(4-nitrophenyl)triazene
2004-04-09

The crystal structure of the title compound, C(14)H(12)N(4)O(3), shows that the stereochemistry about the N=N double bond of the N=N-N(H) moiety is trans. The whole molecule is almost planar (r.m.s. deviation = 0.0654 A), the interplanar angle between the phenyl rings being 0.7 (1) degrees and the largest interplanar angle being that between the phenyl ring and the nitro group of the 4-nitrophenyl substituent [11.5 (2) degrees ]. Intermolecular N-H.O interactions between molecules related by translation give rise to chains along the [110] and [1-10] directions, and these chains are held together by N.O pi-pi interactions. An unequal distribution of the double-bond character among the N atoms suggests a delocalization of pi electrons over the diazoamine group and the adjacent aryl substituents.
Hypermethylation of tumor suppressor genes (p16INK4A, p14ARF and APC) in adenocarcinomas of the upper gastrointestinal tract
2004-04-12

Abstract Aberrant promoter methylation is an important mechanism for gene silencing. In the present study, 50 Barrett's esophagus‐associated esophageal adenocarcinomas (ADC), 50 cardiac ADC and 50 gastric ADC were investigated by means of methylation‐specific real‐time PCR for hypermethylation in the tumor suppressor genes APC , p16 INk4A and p14 ARF . Additionally, expression of p16 INK4A protein in the carcinomas was assessed using immunohistochemistry. Marked differences in hypermethylation were found between esophageal, cardiac and gastric ADC in the APC gene (78% vs . 32% vs . 84%) and in the p16 INK4A gene (54% vs . 36% vs . 10%). Hypermethylation of p14 ARF was absent from esophageal ADC and present infrequently in cardiac (2%) and gastric ADC (10%). Complete loss of p16 INK4A protein expression was detectable in 45% of all tumors and was significantly associated with hypermethylation of the p16 INK4A gene ( p &lt;0.0001, χ 2 ‐test). Our results suggest that hypermethylation of p16 INK4A and APC are frequent findings in esophageal, cardiac and gastric ADC. Additionally, the data point to a tumor specific methylation pattern in upper gastrointestinal ADC. © 2004 Wiley‐Liss, Inc.
Receptor for advanced glycation endproduct (RAGE)–mediated nuclear factor‐κB activation in vasculitic neuropathy
2004-04-12

Abstract Binding of ligands to the receptor for advanced glycation endproducts (RAGE) results in activation of the proinflammatory transcription factor nuclear factor‐kappaB (NF‐κB) and subsequent expression of NF‐κB–regulated cytokines. In order to determine whether engagement of RAGE contributes to the pathogenesis of vasculitic neuropathy, we studied the presence of the RAGE ligand N ε ‐(carboxymethyl)lysine (CML), the receptor itself, NF‐κB, and interleukin‐6 (IL‐6) in sural nerve biopsies of 12 patients with vasculitic neuropathies and 12 controls. In the patients, CML, RAGE, NF‐κB, and IL‐6 were localized in mononuclear cells, epineurial and endoneurial vessels and the perineurium. CML, RAGE, NF‐κB, and IL‐6 were expressed by CD4 + , CD8 + , and CD68 + cells invading the nerves. Controls showed only weak staining. These data suggest that the RAGE pathway plays a critical proinflammatory role in vasculitic neuropathy. Muscle Nerve 29: 853–860, 2004
Extended mutation analysis and association studies of Nurr1 ( NR4A2 ) in Parkinson disease
2004-04-13

Mutations in four genes (α -synuclein, UCH-L1, parkin , and DJ-1 ) have been identified in familial Parkinson disease (PD). Recently, two mutations in the 5′-region of the orphan nuclear receptor Nurr1 ( NR4A2 ) gene have been found in 10% of familial PD cases, of which one-third were of German ancestry.1 Furthermore, a polymorphism in intron 6 of the Nurr1 gene was associated with PD in two independent studies.2,3⇓ The transcription factor Nurr1 is highly expressed in dopaminergic cells of the substantia nigra. Deficiency of Nurr1 in mice leads to a lack of dopaminergic neurons.4 Based on these data, we explored the 7048G7049 polymorphism in intron 6 as well as two novel sequence variations, −291Tdel and −245T→G, in exon 1 of Nurr1 in a large cohort of PD patients. For analysis of the 7048G7049 polymorphism, 424 PD patients were investigated (mean age at disease onset 55.4 ± 12.1 years; 54.6% male, 45.4% female; with 55 patients [13.0%] having a positive family history). For analysis of the two novel sequence variations, −291Tdel and −245T→G, ...
Increased luminal pH in the epididymis of infertile c‐ros knockout mice and the expression of sodium–hydrogen exchangers and vacuolar proton pump H+‐ATPase
2004-04-13

Abstract Transgenic mice targeted for the c ‐ ros gene, which are fertile when heterozygous (HET), but infertile when homozygous (knockout, KO) and associated with failure in pubertal differentiation of the epididymal initial segment, provide a model for studying the role of the epididymal luminal environment in sperm development. Luminal fluid from the cauda epididymidis was measured by both ion‐selective microelectrodes and pH strips to be 0.3 pH units higher in the KO than HET. Of the genes responsible for luminal acidification, expression of mRNA of vacuolar H + ‐ATPase was found in all epididymal regions, but with no difference between KO and HET. Immunohistochemistry showed its presence in epithelial apical cells and clear cells. The Na + –hydrogen exchanger NHE2 was expressed at mRNA and protein levels in the caput but only marginally detectable if at all in the distal epididymis. This was compensated for by NHE3 which was expressed strongest in the cauda region, in agreement with immunohistochemical staining. Quantification of Western blot data revealed slight, but significant, decreases of NHE2 in the caput and of NHE3 in the cauda in the KO mice. The increase in luminal fluid pH in the KO mice could also be contributed to by other epithelial regulating factors including the Na + ‐dependent glutamate transporter EAAC1 formerly reported to be down regulated in the KO. Mol. Reprod. Dev. 68: 159–168, 2004. © 2004 Wiley‐Liss, Inc.
Obesity: An overview on its current perspectives and treatment options
2004-04-14

Obesity is a multi-factorial disorder, which is often associated with many other significant diseases such as diabetes, hypertension and other cardiovascular diseases, osteoarthritis and certain cancers. The management of obesity will therefore require a comprehensive range of strategies focussing on those with existing weight problems and also on those at high risk of developing obesity. Hence, prevention of obesity during childhood should be considered a priority, as there is a risk of persistence to adulthood. This article highlights various preventive aspects and treatment procedures of obesity with special emphasis on the latest research manifolds.
Axial form factor of the nucleon in the perturbative chiral quark model
2004-04-14

We apply the perturbative chiral quark model (PCQM) at one loop to analyze the axial form factor of the nucleon. This chiral quark model is based on an effective Lagrangian, where baryons are described by relativistic valence quarks and a perturbative cloud of Goldstone bosons as dictated by chiral symmetry. We apply the formalism to obtain analytical expressions for the axial form factor of the nucleon, which is given in terms of fundamental parameters of low-energy pion-nucleon physics (weak pion decay constant, strong pion-nucleon form factor) and of only one model parameter (radius of the nucleonic three-quark core).
Lesional RhoA+ cell numbers are suppressed by anti‐inflammatory, cyclooxygenase‐inhibiting treatment following subacute spinal cord injury
2004-04-15

Abstract Inhibition of the small GTPase RhoA or its downstream target Rho‐associated coiled kinase (ROCK) has been shown to promote axon regeneration and to improve functional recovery following spinal cord injury (SCI) in the adult rat. RhoA has also been implicated in delayed secondary injury pathophysiology, such as free radical formation and loss of endothelial integrity leading to edema formation. In the present report, we have analyzed the effect of the central nervous system (CNS) permissive, putatively neuroprotective, anti‐inflammatory cyclooxygenase‐1/‐2 (COX‐1/‐2) inhibitor indomethacin in CNS effective dosage (2 mg/kg/day) on lesional RhoA expression following subacute spinal cord injury. In control rats receiving vehicle alone, RhoA + cells accumulate at the lesion site (Th8). At day 3 following SCI, the RhoA + cellular composition is composed prevailingly of microglia/macrophages and polymononuclear granulocytes, but few reactive astrocytes. In contrast, in the verum group, lesional numbers of RhoA cells were reduced by indomethacin treatment by more than 60% ( P &lt; 0.0001). Inflammation‐dependent RhoA expression accessible by cyclooxygenase inhibition proposes an immune‐related mechanism. Our results identify COX blockers as candidates for a safe, synergistic, adjuvant treatment option in combination with cell‐specific approaches to Rho inactivation, effectively minimizing the pool of RhoA + cells at the lesion site following SCI. © 2004 Wiley‐Liss, Inc.
The oscillation linewidth and noise characteristics of a parallel superconducting quantum interference filter
2004-04-15

The basic requirements providing the unique properties of a superconducting quantum interference filter (SQIF) are discussed. The results of a numerical simulation of the oscillation linewidth for a parallel SQIF are reported and compared with those for a conventional parallel array and single Josephson junction.
Syntheses of the Bi(Pb)-2212 high-Tcsuperconductor through a novel oxide nitrate route
2004-04-15

A novel route is presented for the syntheses of Bi2Sr2CaCu2Ox (Bi-2212) and (Bi,Pb)2Sr2CaCu2Ox (Bi,Pb-2212). Mixtures of oxides, nitrates and carbonates with approximate 2:2:1:2 metal ion compositions are dissolved in HNO3 and dried at 200 °C in air. Afterwards they are reacted under their in situ generated NOx atmosphere in a closed reactor (Staurohr). This reaction forces the system to form the nitrate precursors (Bi,Sr,Ca)2O2NO3/CuO and (Bi,Pb,Sr,Ca)2O2NO3/CuO, respectively. In the final reaction stage these mixtures are converted into Bi(Pb)-2212 under NOx discharge in air.
Trifluoromethanesulfonic Anhydride
2004-04-15

[358-23-6] C2F6O5S2 (MW 282.16) InChI = 1S/C2F6O5S2/c3-1(4,5)14(9,10)13-15(11,12)2(6,7)8 InChIKey = WJKHJLXJJJATHN-UHFFFAOYSA-N (preparation of triflates;1 mild dehydrating reagent; promoter for coupling reactions in carbohydrates2) Alternate Name: triflic anhydride. Physical Data: bp 81–83 °C/745 mmHg; d 1.677 g cm−3; n20D 1.3210. Solubility: soluble in dichloromethane; insoluble in hydrocarbons. Form Supplied in: colorless liquid in ampules. Once opened it should be immediately used. IR, NMR. Preparative Methods: by distillation of Trifluoromethanesulfonic Acid with an excess of Phosphorus(V) sulfide.1 by redistillation with a small amount of P2O5. It is advisable to freshly distill the reagent from a small quantity of P2O5 before use. Handling, Storage, and Precautions: the pure reagent is a colorless liquid that does not fume in air and is stable for a long period. It is not soluble in water and hydrolyzes only very slowly to triflic acid over several days at room temperature. Preferably stored under N2 in a stoppered flask. Dangerously exothermic reactions have been reported when attempting to triflate hindered alcohols.67
[{(H3C)3NB(H)2NC}2Au][AuI2]: a linear chain polymer of gold(I) iodide with an unusual isocyanoborane ligand showing aurophilic behaviour
2004-04-17

Treatment of the (isocyanoborane) gold(I) chloride adduct [LAuCl] [L = (H3C)(3)NB(H)(2)NC] with KI at room temperature yields the unusal title compound, bis[isocyano(trimethylamino) borane] gold(I) diiodoaurate(I), [Au(C4H11BN2)(2)][ AuI2], which forms via an in situ rearrangement of isocyanoborane and halide ligands. The structure consists of alternating [L2Au](+) and [AuI2](-) ions, which form an infinite linear one-dimensional chain due to aurophilic Au...Au interactions. Both Au atoms occupy inversion centres.
Development of the high-temperature phase of hexagonal manganites
2004-04-19

Reports about the ferroelectric ordering temperatures in the multiferroic hexagonal system are controversial: transition temperatures varying between and are reported for the same material. To elucidate the structural changes leading to ferroelectric distortions in hexagonal manganites, we calculate the irreducible representations of the distortions from the possible high-temperature symmetry to the low-temperature symmetry There are four different orthogonal modes, of which only one allows a spontaneous electric polarization. Structure refinements and an accurate statistical analysis of neutron powder-diffraction data of based on this group-theoretical analysis, reveal two phase transitions: We extrapolate a polar to nonpolar transition temperature of where the hexagonal bitetrahedra start to tilt, while the ferroelectric distortion appears at For Yb the tilt of the bitetrahedra and the buckling of the R layers as well as the ferroelectric distortion were extrapolated to comparable temperatures.
Organotin Dyes: Synthesis and Structural Characterization of Dibutyltin and Dimethyltin Complexes with 2, 2′‐Dihydroxyazobenzene
2004-04-20

Abstract The preparation and structures of 2, 2′‐dihydroxyazobenzenato‐dibutyl‐tin [Bu 2 SnL] and 2, 2′‐dihydroxyazobenzenato‐dimethyl‐tin [Me 2 SnL] are described. The complexes were characterized by IR, NMR ( 1 H, 13 C, 119 Sn) and UV/VIS spectra. The crystal structures were determined by X‐ray diffraction on single crystals. [Bu 2 SnL]: monoclinic, space group P2 1 /c, cell constants at 208 K: a = 860.73(5), b = 973, 51(18), c = 2340.0(3) pm, β = 93.615(11)°; R 1 = 0.0546. [Me 2 SnL]: orthorhombic, space group Pbcn, cell constants at 208 K: a = 1914.6(4), b = 1041.3(3), c = 1323.27(14) pm; R 1 = 0.0529.
Motion Perception Without Explicit Activity in Areas MT and MST
2004-04-20

It is widely accepted that middle temporal (MT) and middle superior temporal (MST) cortical areas in the brain of rhesus monkeys are essential for processing visual motion. We asked whether this assumption holds true if the moving stimulus consists of a second-order motion stimulus. In addition, we asked whether neurons in area MT and MST code for moving sound sources. To answer these questions, we trained three rhesus monkeys on a direction-discrimination task. Our monkeys were able to correctly report the direction of all motion stimuli used in this study. Firing rates of directionally selective neurons from area MT ( n = 38) and MST ( n = 68) were recorded during task performance. These neurons coded only for the stimulus movement if the motion stimulus was separated from the background by luminance or flicker (Fourier and drift-balanced motion). If these segregation cues were absent (in the case of theta motion and of the moving sound source), firing rates did not code for the stimulus' direction. Therefore we conclude that although areas MT and MST are undoubtedly involved in processing a moving stimulus, they are not the final cortical stages responsible for perceiving it.
Electronic properties of interfaces between model organic semiconductors and metals
2004-04-21

We present a summary of recent studies of the interface properties of interfaces that are formed between well-established molecular organic semiconductors and various metals. The energy level alignment, the formation of interface dipoles, a possible band bending and interactions at the interfaces have been investigated using photoemission spectroscopy, while polarization-dependent X-ray absorption spectroscopy provided information on the molecular orientation at the interfaces. The observed interface characteristics reach from physisorption to a reaction depending upon both the substrate and the organic molecule under investigation. Different contributions to the often observed interface dipoles are discussed. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)