bluuebunny/crossref_metadata_2025_split huggingface dataset:
Outcomes in the treatment of thrombotic thrombocytopenic purpura with splenectomy: A retrospective cohort study
Authors: Outschoorn Ubaldo Martinez , Ferber Andres 
Published: August 2006

AbstractThe mainstay of treatment for thrombotic thrombocytopenic purpura (TTP) is plasma exchange (PE), but the role of splenectomy is still undefined. The records of all patients with TTP at a single center over a 20‐year period were retrospectively reviewed. Response to plasma exchange was determined. The outcome of patients treated with splenectomy in the setting of TTP was evaluated. Sixty‐one patients had been treated for TTP. Thirty‐nine patients (64%) achieved complete remission (CR) with PE, nineteen (31%) of these achieving sustained CR and seventeen (28%) with relapsed TTP. Twenty patients (33%) had PE refractory TTP and two patients (3%) had PE dependent TTP. During this time period, 10 patients (16%) underwent splenectomy, four patients (7%) for PE dependent TTP, three (5%) for relapsed TTP, and three (5%) for refractory TTP. All of the patients achieved CR after splenectomy. Two patients who had undergone splenectomy had subsequent relapses, both with previously relapsed TTP. In relapsed patients the relapse rate after splenectomy was 0.27 events per patient year compared to 0.6 events per patient year before splenectomy. Median follow‐up after splenectomy was 19 months (range 0.13–90 months). In conclusion, relapses in TTP can be managed successfully with additional PE or with splenectomy. PE dependent or refractory TTP can be successfully treated with splenectomy. Am. J. Hematol., 2006. © 2006 Wiley‐Liss, Inc.
Waldenstrom's macroglobulinemia presenting with spinal cord compression: A case report
Authors: Al‐Halabi Hani , Roberge David 
Published: August 2006

AbstractWaldenstrom's macroglobulinemia (WM) is a rare lymphoplasmacytic lymphoma characterized by a wide range of clinical presentations related to direct tumor infiltration and the production of IgM. Most commonly it presents with cytopenia, hepatosplenomegaly, lymphadenopathy, constitutional symptoms, and hyperviscosity syndrome. We report a case of WM in an 81‐year‐old man who initially presented with severe back pain. The patient had no peripheral lymphadenopathy or hepatosplenomegaly and his peripheral blood smear was normal. MRI of the spine revealed an epidural mass causing spinal cord compression at T9. Surgical decompression was performed and pathological analysis of the mass revealed a lymphoproliferative B‐cell process. The diagnosis of WM was established after cytomorphologic and immunohistochemical analysis of the patient's bone marrow revealed the presence of a lymphoid/lymphoplasmacytoid‐like bone marrow infiltrate along with an elevated serum IgM level. The patient responded both clinically and serologically to local radiotherapy. This case is unusual because the patient lacked all common clinical features of WM. This is the first reported case of epidural spinal cord compression as the initial manifestation of WM, adding to the spectrum of clinical presentations seen in this disease. Am. J. Hematol., 2006. © 2006 Wiley‐Liss, Inc.
Modelling stylized features in default rates
Authors: Taufer Emanuele 
Published: August 2006

AbstractWe propose a stochastic model for the probability of default based on diffusions with given marginal distribution and autocorrelation function. The model tries to capture stylized features observed in historical default rates and is analytically tractable. Estimation procedures and expressions for analysis and prediction are provided. Copyright © 2006 John Wiley & Sons, Ltd.
Structural and spectroscopic analysis of hydrogensquarates of glycine‐containing tripeptides
Authors: Koleva Bojidarka B. , Kolev Tsonko M. , Spiteller Michael 
Published: August 2006

AbstractThe hydrogensquarates of glycine‐containing tripeptides glycylglycylglycine (H‐Gly‐Gly‐Gly‐OH), glycylglycylmethionine (H‐Gly‐Gly‐Met‐OH), and methionylglycylglycine (H‐Met‐Gly‐Gly‐OH) have been characterized structurally. Quantum chemical ab initio calculations, solid‐state linear‐dichroic infrared (IR–LD) spectroscopy, 1H and 13C NMR data, ESI‐MS, HPLC‐MS/MS, TGV, and DSC methods were employed. The structures consist in a positively charged peptide moiety and a negative hydrogensquarate anion (HSq−), stabilized by strong intermolecular hydrogen bonds. © 2006 Wiley Periodicals, Inc. Biopolymers 83: 498–507, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
The chemical synthesis of the GstI protein by NCL on a X‐Met site
Authors: Saporito Angela , Marasco Daniela , Chambery Angela , Botti Paolo , Monti Simona M. , Pedone Carlo , Ruvo Menotti 
Published: August 2006

AbstractThe small GstI protein (63 amino acids) of Rhizobium leguminosarum is the endogenous inhibitor of the glnII (glutamine synthetase II) gene expression. It has been suggested that GstI has a predominantly β‐structure and mediates the block of translation and stabilization of glnII mRNA through direct binding to its 5′ untranslated region. Because of the unavailability of adequate amounts of purified recombinant protein, the mechanism as well as the protein tridimensional structure remain very poorly understood. To obtain the full‐length protein, we have undertaken the chemical synthesis of the protein by different approaches. In a first attempt, the stepwise synthesis was unsuccessful, with strong aggregation experienced on the N‐terminal side, after residue 44 from the C‐terminus. In a second approach, we set up the conditions to carry out a native chemical ligation (NCL). Albeit the protein contains two Cysteine residues, located at positions 40 and 47, to minimize the size of the N‐terminal segment to be synthesized, we have devised an alternative strategy of ligation on Met32, utilizing homoCys as the ligating moiety and then alkylating the resulting polypeptide with methyl iodide. New conditions to quantitatively methylate thiol groups in complex polypeptides have been conceived, obtaining the protein in very good yields and purity. A CD spectroscopy investigation has revealed that the protein does not adopt canonical secondary structures but is very rich in β‐structure (∼ 60%), in agreement with a previous study carried out on samples obtained by recombinant methods. © 2006 Wiley Periodicals, Inc. Biopolymers 83: 508–518, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
The interplay of sequence and stereochemistry in defining conformation in proteins and polypeptides
Authors: Ranbhor Ranjit , Ramakrishnan Vibin , Kumar Anil , Durani Susheel 
Published: August 2006

AbstractSequential specification of conformation in proteins and polypeptides is a triangular interplay involving the system of linked peptides, the sequences in side chains, and water as solvent. Stereochemistry in side chain linkages is obviously important in the interaction between all of the players, but no specification of its explicit role, if any, in linking sequence with conformation has been made. Flory and coworkers made a puzzling observation in 1967 that, when mutated from poly‐L to alternating‐L,D stereochemical structure, polypeptides will suffer a reduction in overall dimension or characteristic ratio by an astonishing factor of 10 and to a value even lower than that predicted for free rotation (Miller, W. G.; Brant, D. A.; Flory, P. J. J Mol Biol 1967, 23, 67–80). Enquiring into this longstanding puzzle, Durani and coworkers found that the stereochemical modification will also abolish conformational sensitivity in polypeptide structure to solvent, because electrostatic interactions in the system of linked peptides are transformed from a condition of mutual conflict to one of harmony (Ramakrishnan, V.; Ranbhor, R.; Kumar, A.; Durani, S. J Phys Chem B 2006, 110, 9314–9323). Thus, poly‐L stereochemistry could be the fulcrum linking sequences with ϕ,ψs in protein and polypeptide structures, via dielectric arbitrations in a conflicting type of interpeptide electrostatics, in agreement with the electrostatic screening model of Avbelj and Moult (Avbelj, F.; Moult, J. Biochemistry 1995, 34, 755–764). © 2006 Wiley Periodicals, Inc. Biopolymers 83: 537–545, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Syntheses, Photophysical Properties, and Application of Through‐Bond Energy‐Transfer Cassettes for Biotechnology
Authors: Jiao Guan‐Sheng , Thoresen Lars H. , Kim Taeg Gyum , Haaland Wade C. , Gao Feng , Topp Michael R. , Hochstrasser Robin M. , Metzker Michael L. , Burgess Kevin 
Published: August 2006

AbstractWe have designed fluorescent “through‐bond energy‐transfer cassettes” that can harvest energy of a relatively short wavelength (e.g., 490 nm), and emit it at appreciably longer wavelengths without significant loss of intensity. Probes of this type could be particularly useful in biotechnology for multiplexing experiments in which several different outputs are to be observed from a single excitation source. Cassettes 1–4 were designed, prepared, and studied as model systems to achieve this end. They were synthesized through convergent routes that feature coupling of specially prepared fluorescein‐ and rhodamine‐derived fragments. The four cassettes were shown to emit strongly, with highly efficient energy transfer. Their emission maxima cover a broad range of wavelengths (broader than the four dye cassettes currently used for most high‐throughput DNA sequencing), and they exhibit faster energy‐transfer rates than a similar through‐space energy‐transfer cassette. Specifically, energy‐transfer rates in these cassettes is around 6–7 ps, in contrast to a similar through‐space energy‐transfer system shown to have a decay time of around 35 ps. Moreover, the cassettes are considerably more stable to photobleaching than fluorescein, even though they each contain fluorescein‐derived donors. This was confirmed by bulk fluorescent measurements, and in single‐molecule‐detection studies. Modification of a commercial automated DNA‐sequencing apparatus to detect the emissions of these four energy‐transfer cassettes enabled single‐color dye–primer sequencing.
Fest/Flüssig‐Trennung mit synthetischen und natürlichen Polymeren
Authors: Schwarz S. , Jaeger W. , Petzold G. , Bratskaya S. , Heinze T. , Liebert T. , Krentz O. , Kulicke W.‐M. , Paulke B.‐R. 
Published: August 2006

AbstractFest/Flüssig‐Trennprozesse sind sowohl in der Abwasserbehandlung als auch bei zahlreichen technischen Verfahren von wesentlicher Bedeutung. Die rationelle Durchführung von Koagulations‐, Flockungs‐ und Retentionsprozessen erfordert meist den Einsatz von Flockungsmitteln als Hilfsmittel. In diesem Beitrag wird über Flockungsergebnisse mit sowohl hydrophoben synthetischen Polyelektrolyten als auch neuen kationischen Stärkederivaten berichtet. Die gewählten Untersuchungsbedingungen ermöglichen dabei eine sehr gute Vergleichbarkeit der Resultate.
Neue Aspekte der Modellierung bei der Fluiddynamik von Packungskolonnen
Authors: Maćkowiak J. 
Published: August 2006

AbstractIn Anlehnung an das modifizierte Kanalmodell mit teils offener Umwandung und auf der Grundlage des Tropfen‐Schwebebettmodells (TSB‐Modell) wird eine neue Beziehung zur Bestimmung des Druckverlustes von unberieselten Schüttungen und Packungen bei der Einphasenströmung vorgestellt. An Beispielen wird gezeigt, dass es für geometrisch einfache Füllkörperformen möglich ist, ein allgemein gültiges Widerstandsgesetz für alle Füllkörperformen aufzustellen. Mit der neuen Gleichung kann man den die Form eines Füllkörpers kennzeichnenden Formfaktor ohne Experimente für eine ganze Reihe von bekannten Füllkörpern lediglich aus der Füllkörpergeometrie vorausberechnen, ohne Versuchsdaten auswerten zu müssen. Für komplizierte Füllkörperformen müssen jedoch zwecks Absicherung der Aussagen einige wenige Versuchsdaten zur Einphasenströmung an luftdurchströmten Füllkörperschüttungen oder Packungen vorliegen.
Dispergierscheiben, die bessere Alternative zum Hochdruck beim Emulgieren?
Authors: Urban K. , Wagner G. , Schaffner D. , Ulrich J. 
Published: August 2006

AbstractHeutzutage finden Emulsionen eine breite Anwendung in der Industrie und im täglichen Leben. Neben Hochdruckemulgiersystemen stellen Dispergier‐/Dissolverscheiben eine einfache Möglichkeit dar, insbesondere hochviskose Emulsionen mit sehr langsamen Emulgatoren mit mittleren Tropfengrößen bis ca. 130 nm und engen Verteilungsbreiten zu erzeugen. Dabei sind sie vor allem kostengünstiger und bereiten weniger Probleme beim Scale up.
Verkokung und Koksabbrand in heterogenen Katalysatoren
Authors: Kern C. , Jess A. 
Published: August 2006

AbstractBei heterogen‐katalysierten Reaktionen mit organischen Einsatzstoffen kommt es häufig zu einer Deaktivierung der Katalysatoren durch die Bildung von Koksablagerungen. In der Praxis werden die verkokten Katalysatoren durch den Abbrand des Kokses mit Sauerstoff regeneriert und so die Aktivität der Katalysatoren wiederhergestellt. Auf dem Gebiet der Verkokung und des Koksabbrands ist in der Literatur eine Vielzahl von Forschungsarbeiten zu finden, die sich aber vornehmlich aus Sicht der Grundlagenforschung qualitativ mit dem Thema beschäftigen, also etwa mit Fragen der chemischen Struktur der Koksablagerungen. Der vorliegende Beitrag soll neben einem Überblick über diese Ergebnisse in erster Linie die Katalysatorregeneration durch den Koksabbrand sowohl im Einzelkorn als auch in einem Festbettreaktor näher beleuchten, da dieser Prozess bisher nur wenig Beachtung gefunden hat.
Isoperibole Kalorimetrie in der sicherheitstechnischen Praxis
Authors: Winkler S. , Lade M. , Vogel H. 
Published: August 2006

AbstractIn den Betrieben der chemischen Industrie werden zur Produktherstellung Stoffumwandlungen durchgeführt, die in den meisten Fällen unter Freisetzung von Wärme verlaufen. Somit nimmt die sicherheitstechnische Beurteilung von Reaktionen mit Hilfe der Kalorimetrie eine wichtige Rolle ein. Da während der Verfahrensentwicklung häufig nur geringe Probenmengen vorhanden sind, wird in diesem Beitrag ein isoperiboles Kalorimeter mit kleinem Reaktorvolumen und dessen Anwendung für unterschiedliche Reaktionstypen vorgestellt.
Einsatz und Potenzial der integrierten Miniplant‐Technologie für die Enzymkatalyse
Authors: Berendsen W. R. , Samorski M. 
Published: August 2006

AbstractDie Kombination aus Miniplant‐Technik, Modellierung und Simulation, die auch als integrierte Miniplant‐Technologie bezeichnet wird, ist Stand der Technik in der chemischen Verfahrenstechnik. Sie bietet auch für die Verfahrensentwicklung enzymkatalysierter Reaktionen enorme Verbesserungspotenziale. Neben einer Übersicht über die Anwendungsgebiete der integrierten Miniplant‐Technologie wird der Nutzen für die enzymatische Reaktionstechnik anhand zweier Beispiele aus der aktuellen Forschung vorgestellt. Im ersten Beispiel werden die Erkenntnisse aus dieser Technologie zur Nachhaltigkeitsbewertung von Verfahrensalternativen genutzt. Das zweite Beispiel verdeutlicht, wie durch eine Rückkopplung von Miniplant‐Ergebnissen und ‐Simulationen sowohl eine Verbesserung des Biokatalysators als auch des Verfahrens erreicht werden kann.
Instationäre Betriebsweise zur Leistungssteigerung technischer Rieselbettreaktoren
Authors: Schubert M. , Bauer T. , Lange R. 
Published: August 2006

AbstractDie Leistung und die Wirtschaftlichkeit stationär betriebener Rieselbettreaktoren werden hauptsächlich durch die Katalysatoreffektivität, den Druckverlust sowie die Gas/Flüssig‐Verteilung in der Katalysatorschüttung begrenzt. Zur Leistungssteigerung der Rieselbettreaktoren hat sich die instationäre Betriebsweise als eine geeignete Strategie herausgestellt. Diese Leistungssteigerung umfasst die Erhöhung von Umsatz, Selektivität und Produktivität. Zusätzlich kann die Reaktorsicherheit durch die gezielte Vermeidung von Hot Spots erhöht werden. Der Beitrag diskutiert den Stand der Technik einer instationären Betriebsweise und die Anwendungsmöglichkeiten bei technischen Rieselbettreaktoren.
Determination of the Bound Conformation of a Competitive Nanomolar Inhibitor of Mycobacterium tuberculosis Type II Dehydroquinase by NMR Spectroscopy
Authors: Prazeres Verónica F. V. , Sánchez‐Sixto Cristina , Castedo Luis , Canales Ángeles , Cañada Francisco Javier , Jiménez‐Barbero Jesús , Lamb Heather , Hawkins Alastair R. , González‐Bello Concepción 
Published: August 2006

AbstractThe synergy between tuberculosis and the AIDS epidemic, along with the surge of multidrug‐resistant isolates of M. tuberculosis, has reaffirmed tuberculosis as a primary public health threat. It is therefore necessary to discover new, safe, and more efficient antibiotics against this disease. On the other hand, mapping the dynamic interactions of inhibitors of a target protein can provide information for the development of more potent inhibitors and consequently, more potent potential drugs. In this context, the conformational binding of our previously reported nanomolar inhibitor of M. tuberculosis type II dehydroquinase, the 3‐nitrophenyl derivative 1, was studied using saturation transfer difference (STD) and transferred NOESY experiments. These studies have shown that in the bound state, one conformation of those present in solution of the competitive nanomolar inhibitor 3‐nitrophenyl derivative 1 is selected. In the bound conformation, the aromatic ring is slightly shifted from coplanarity, with the double bond and the nitro group of 1 oriented towards the double bond side.
Vinorelbine, doxorubicin, and prednisone in androgen‐independent prostate cancer
Authors: Borden Lester S. , Clark Peter E. , Lovato James , Hall M. Craig , Stindt Diana , Harmon Michele , M. Mohler Randi , Torti Frank M. 
Published: August 2006

AbstractBACKGROUND.Ultimately, patients with metastatic prostate cancer progress on androgen ablation therapy. The investigation of new chemotherapeutic regimens for the treatment of androgen‐independent prostate cancer (AIPC) is essential. The authors conducted a Phase II trial with vinorelbine, doxorubicin, and daily prednisone (NAP) to investigate the antitumor activity and palliative response of this regimen in patients with AIPC.METHODS.Forty‐six patients entered this Phase II combination chemotherapy trial. Patients were treated with both vinorelbine and doxorubicin at doses of 20 mg/m2 on Days 1, 8, and 15 every 28 days and prednisone 5 mg twice daily. Endpoints included prostate‐specific antigen (PSA) response and palliation, as measured by the Functional Assessment of Cancer Therapy‐Prostate (FACT‐P) instrument, the Brief Pain Inventory Scale, and a narcotic analgesic log.RESULTS.The median follow‐up for all 46 patients was 13.4 months. Fifty‐two percent of patients had impaired performance status at baseline. One responding patient remained on NAP and was progression‐free at 11.5 months. Thirty‐nine patients progressed, 3 patients died prior to response assessment, and 3 patients refused therapy. The median overall survival was 57 weeks (95% confidence interval [95% CI], 36–76 weeks), and the median time to disease progression was 17 weeks (range, 11–24 weeks). The PSA response among the 36 patients who completed 3 cycles of NAP was 42% (95% CI, 26–59%). There was a statistically significant improvement in quality of life measured both by the FACT‐General instrument (P = .03) and the FACT‐P instrument (P = .0006) over the 3 months compared with baseline measurements. Pain medicine use also improved: The median morphine equivalents among patients who were taking pain medications at the time of study enrollment showed a substantial decline after 1 cycle of treatment that was maintained. Pain (as assessed by the Brief Pain Inventory) improved compared with baseline pain at the 2nd‐month assessment (worst pain, P = .08; least pain, P = .02; and average pain, P = .003). Overall, the regimen was tolerated well. The most common side effects were mild fatigue and gastrointestinal complaints (all of which were Grade 1 or 2 [according to Version 2.0 of the Expanded Common Toxicity Criteria]). Seventeen patients (37%) experienced Grade 3 or 4 neutropenia. Five patients (11%) developed a cardiac ejection fraction of <50% during treatment and had doxorubicin discontinued. No patients developed clinical congestive heart failure.CONCLUSIONS.The NAP combination produced substantive palliation and a moderate response rate in men with AIPC. Cancer 2006. © American Cancer Society.
Theoretical Dynamic Studies on the Reaction of CH3C(O)CH3−nFn with the Hydroxyl Radical and the Chlorine Atom
Authors: Ji Yue‐Meng , Wang Li , Li Ze‐sheng , Liu Jing‐yao , Sun Chia‐chung 
Published: August 2006

AbstractThe mechanisms of the reactions: CH3C(O)CH2F+OH/Cl→products (R1/R2) and CH3C(O)CF3+OH/Cl→products (R3/R4) are studied over a wide temperature range (200–2000 K) by means of the dual‐level direct dynamics method. The optimized geometries and frequencies of the stationary points are calculated at the MP2/cc‐pVDZ and B3LYP/6‐311G(d,p) levels. The energy profiles of the reactions are then refined with the interpolated single‐point‐energy method (ISPE) at the BMC‐CCSD level. The canonical variational transition‐state theory (CVT) with the small‐curvature‐tunneling (SCT) correction method is used to calculate the rate constants. Using group‐balanced isodesmic reactions as working chemical reactions, the standard enthalpies of formation for CH3C(O)CH2F, CH3C(O)CF3, CH3C(O)CHF, CH2C(O)CH2F, and CH2C(O)CF3 are evaluated at the CCSD(T)/6‐311+G(2d,p)//MP2/cc‐pVDZ level of theory. The results indicate that the hydrogen abstraction is dominated by removal from the fluoromethyl position rather than from the methyl position.
A Theoretical Study of the Mechanism and Kinetics of F+N3 Reactions
Authors: Ma Haitao , Liu Xiaojun , Bian Wensheng , Meng Lingpeng , Zheng Shijun 
Published: August 2006

AbstractBoth the singlet(1A′) and triplet(3A′′) potential energy surfaces (PESs) of F+N3 reactions are investigated using the complete‐active‐space self‐consistent field (CASSCF) and the multireference configuration interaction (MRCI) methods with a proper active space. The minimum energy crossing point (MECP) at the intersection seam between the 1A′ and 3A′′ PESs is located and used to clarify the reaction mechanisms. Two triplet transition states are found, with one in the cis form and the other one in the trans form. Further kinetic calculations are performed with the canonical unified statistical (CUS) theory on the singlet PES and the improved canonical variational transition‐state (ICVT) method on the triplet PES. The rate constants are also reported. At 298 K, the calculated rate constant is in reasonably good agreement with experimental values, and spin–orbit coupling effects lower it by 28 %. The spectroscopic constants derived from the fitted potential‐energy curves for the singlet and triplet states of NF are in very good agreement with experimental values. Our calculations indicate that the adiabatic reaction on the singlet PES leading to NF(a1Δ)+N2 is the major channel, whereas the nonadiabatic reaction through the MECP, which leads to NF(X3Σ−)+N2, is a minor channel.