gebhart/patrepeval huggingface dataset:
Fluorous Catalysis without Fluorous Solvents:  A Friendlier Catalyst Recovery/Recycling Protocol Based upon Thermomorphic Properties and Liquid/Solid Phase Separation (2001)

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTFluorous Catalysis without Fluorous Solvents: A Friendlier Catalyst Recovery/Recycling Protocol Based upon Thermomorphic Properties and Liquid/Solid Phase SeparationMarc Wende, Ralf Meier, and J. A. GladyszView Author Information Institut für Organische Chemie Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 42 91054 Erlangen, Germany Cite this: J. Am. Chem. Soc. 2001, 123, 46, 11490–11491Publication Date (Web):October 27, 2001Publication History Received12 June 2001Published online27 October 2001Published inissue 1 November 2001https://pubs.acs.org/doi/10.1021/ja011444dhttps://doi.org/10.1021/ja011444drapid-communicationACS PublicationsCopyright © 2001 American Chemical SocietyRequest reuse permissionsArticle Views1297Altmetric-Citations166LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Catalysts,Chromatography,Group 15 compounds,Solubility,Solvents Get e-Alerts
Epidemiology of pertussis in a developed country with low vaccination coverage: the Italian experience. (1992)

In Italy pertussis vaccination is optional. Fewer than 40% of children younger than 5 years of age are vaccinated, and pertussis remains a common childhood disease. We use data from a variety of sources to examine trends and characteristics of Italian children with pertussis and reasons behind the low vaccine coverage. Approximately 25% of Italian children have experienced clinical pertussis by their fifth birthday. The disease is most severe in those less than 1 year of age; in this group an estimated 1 in 14 cases are hospitalized and 1 in 850 die. The incidence appears to be increasing in the 1- to 4-year age group despite increased vaccination coverage. The low vaccine coverage appears to be caused by the ambivalence of the Italian pediatric community about the vaccine rather than parental concerns about vaccine safety. Legislation is being considered to make pertussis vaccination mandatory.
Solid Solution of CdyZn1-yS Nanosized Particles:  Photophysical Properties (1997)

Optical properties of CdyZn1-yS nanoparticles differing by their size and composition are presented. The fluorescence quantum yield increases with increasing particle size and composition (y). The photoluminescence, PL, spectra are due to defect states and follow the quantum size effect. A red-shift in the fluorescence spectrum with increasing cadmium composition and particle size is observed which is attributed to a transition from the valence band to a deeply trapped hole. Both absorption and fluorescence spectra in various media and at temperatures from 77 to 300 K are presented.
Cytogenetic responses in high-risk myelodysplastic syndrome following low-dose treatment with the DNA methylation inhibitor 5-aza-2'-deoxycytidine (2001)

Decitabine (5-aza-2'-deoxycytidine) acts as a powerful demethylating agent in vitro. Clinically, low-dose decitabine ameliorates cytopenias including induction of trilineage responses in approximately 50% of patients with high-risk myelodysplastic syndrome (MDS). We examined the incidence and kinetics of cytogenetic responses to decitabine in these patients. Of 115 successfully karyotyped patients, 61 (53%) had clonal chromosomal abnormalities prior to treatment. Major cytogenetic responses were observed in 19 patients (31% of those with abnormal cytogenetics, 17% of all patients by intention-to-treat) after a median of three courses (range, 2-6) until best cytogenetic response. Progressive decrease of the abnormal clone over time was also determined using fluorescence in situ hybridization (FISH) analysis in two patients. Median duration of cytogenetic responses was 7.5 months (range, 3-15). Analysis of response by the International Prognostic Scoring System (IPSS) cytogenetic risk groups revealed three out of five cytogenetic responses (60%) in the IPSS 'low-risk' group, 6 out of 30 with 'intermediate risk' (20%) and 10 out of 26 in the 'high-risk' group (38%). Median survival in these cytogenetic subgroups was 30, 8 and 13 months respectively. The relative risk of death in patients achieving a major cytogenetic response was 0.38 (95% confidence interval 0.17-0.88) compared with patients in whom the cytogenetically abnormal clone persisted (P = 0.0213). In conclusion, repeated courses of low-dose decitabine induce cytogenetic remissions in a substantial number of elderly MDS patients with pre-existing chromosomal abnormalties; these are associated with improved survival compared with patients in whom the cytogenetically abnormal clone persists. Patients with 'high-risk' chromosomal abnormalities may particularly benefit from this treatment.
Bile acid synthesis from newly synthesized vs. preformed cholesterol precursor pools in the rat (1993)

The present study defines the origin of cholesterol subserving bile acid synthesis in male rats with an extracorporal bile duct by labeling newly formed cholesterol with tritiated water. Within 6 hr after interruption of the enterohepatic circulation, the bile acid pool was depleted. At this early time point the proportion from de novo cholesterol was 8% and 12% for biliary cholesterol and cholate, but 18% and 19% for muricholate and chenodeoxycholate, respectively. This proportion gradually rose to 40%, 34%, 51% and 51%, respectively, at 15 to 30 hr. At 78 hr after bile diversion, 64% of cholate was labeled, compared with 84% to 88% of the other biliary lipids and 71% of plasma cholesterol. Total and labeled bile acid secretion exhibited the same diurnal rhythm. To allow differentiation between direct hepatocytic de novo synthesis of bile acids from acetate and recycling of labeled plasma cholesterol, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (pravastatin) was infused from 54 to 78 hr. It suppressed total synthesis of primary bile acids by 60% to 80% but decreased the tritium label of bile acids only from a range of 74% to 92% (54 hr) to a range of 54% to 63% (78 hr), which was in the range of plasma cholesterol (58%). We conclude that bile acids and biliary cholesterol are synthesized mostly from preformed (i.e., plasma) cholesterol, both immediately after depletion of the pool in enterohepatic circulation and after derepression. Moreover, the hepatic cholesterol pools subserving the synthesis of different bile acids and biliary cholesterol secretion are not identical.
Infarct Tissue Heterogeneity by Magnetic Resonance Imaging Identifies Enhanced Cardiac Arrhythmia Susceptibility in Patients With Left Ventricular Dysfunction (2007)

Tissue heterogeneity is present and quantifiable within human infarcts. More extensive tissue heterogeneity correlates with increased ventricular irritability by programmed electrical stimulation. These findings support the hypothesis that anatomic tissue heterogeneity increases susceptibility to ventricular arrhythmias in patients with prior myocardial infarction and LV dysfunction.
Long-Term Analysis of LASIK for the Correction of Refractive Errors After Penetrating Keratoplasty (2005)

Purpose: To determine the long-term safety and effectiveness of laser-assisted in situ keratomileusis (LASIK) in the treatment of refractive errors following penetrating keratoplasty.Methods: A retrospective review was done of 57 eyes of 48 patients with anisometropia or high astigmatism who were unable to wear glasses or a contact lens after penetrating keratoplasty and who underwent LASIK for visual rehabilitation.Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BCVA), and corneal transplant integrity were recorded before surgery as well as up to 60 months after LASIK.Results: The mean follow-up after the LASIK was 21.4 ± 14.2 months (range, 3-60 months).Mean preoperative spherical equivalent (SE) was -4.19 ± 3.38 diopters (D).Mean preoperative astigmatism was 4.67 ± 2.18 D. Preoperative BCVA was 20/40 or better in 42 eyes (74%).At 2 years the mean SE was -0.61 ± 1.81 D and mean astigmatism was 1.94 ± 1.35 D for the 28 eyes with follow-up.UCVA was 20/40 or better in 12 eyes (43%), and BCVA was 20/40 or better in 24 eyes (86%) at 2 years.A gain in BCVA of one line or more was seen in eight eyes (29%).Two eyes (7%) had loss of two or more lines of BCVA at 2 years.Nine eyes (16%) developed epithelial ingrowth.Five eyes (9%) in this series had repeat corneal transplants.Conclusions: LASIK is effective for reducing ametropia after penetrating keratoplasty.Proper patient counseling is necessary because the results of LASIK after penetrating keratoplasty are not as good as, and complications are more frequent than, in eyes with naturally occurring myopia and astigmatism.Complications are especially common in patients with mismatch of the donor and host cornea and in those with poor endothelial cell function.
Apolipoprotein E associates with beta amyloid peptide of Alzheimer's disease to form novel monofibrils. Isoform apoE4 associates more efficiently than apoE3. (1994)

Late-onset and sporadic Alzheimer's disease are associated with the apolipoprotein E (apoE) type 4 allele expressing the protein isoform apoE4. Apolipoprotein E binds avidly to beta amyloid (A beta) peptide, a major component of senile plaque of Alzheimer's disease, in an isoform-specific manner. The apoE4 isoform binds to A beta peptide more rapidly than apoE3. We observed that soluble SDS-stable complexes of apoE3 or apoE4, formed by coincubation with A beta peptide, precipitated after several days of incubation at 37 degrees C with apoE4 complexes precipitating more rapidly than apoE3 complexes. A beta(1-28) and A beta(1-40) peptides were incubated in the presence or absence of apoE3, apoE4, or bovine serum albumin for 4 d at 37 degrees C (pH 7.3). Negative stain electron microscopy revealed that the A beta peptide alone self-assembled into twisted ribbons containing two or three strands but occasionally into multistranded sheets. The apoE/A beta coincubates yielded monofibrils 7 nm in diameter. ApoE4/A beta coincubates yielded a denser matrix of monofibrils than apoE3/A beta coincubates. Unlike purely monofibrillar apoE4/A beta coincubates, apoE3/A beta coincubates also contained double- and triple-stranded structures. Both apoE isoforms were shown by immunogold labeling to be uniformly distributed along the A beta peptide monofibrils. Monofibrils appeared earlier in apoE4/A beta than in apoE3/A beta in time-course experiments. Thus apoE3 and apoE4 each interact with beta amyloid peptide to form novel monofibrillar structures, apoE4 more avidly, a finding consistent with the biochemical and genetic association between apoE4 and Alzheimer's disease.
Efficient and Convenient Nonaqueous Workup Procedure for the Preparation of Arylboronic Esters (2002)

An efficient one-pot synthetic protocol for the synthesis of arylboronic esters has been established. The concentrated addition mixture of trimethylborate with aryl Grignard reagents was treated with low molecular weight diols (ethylene glycol, 1,3-propandiol) and toluene, the corresponding arylboronic esters were isolated in a convenient way with high yields. The diols not only serve as water replacement for the workup step, but also as well as the reagent for the preparation of arylboronic esters.
Three‐Dimensional Magnesia‐Based Nanocrystal Assemblies Via Low‐Temperature Magnesiothermic Reaction of Diatom Microshells (2005)

A low‐temperature (≤700°C) magnesiothermic reaction has been used for the first time to convert three‐dimensional (3‐D) silica‐based diatom microshells into nanocrystalline magnesia‐based replicas. Exposure of diatom microshells to Mg( g ) at only 650°–700°C resulted in the initial (direct) formation of MgO and Si nanocrystals (≤5 nm), that is, no intermediate magnesium silicate compounds were detected. Further reaction of Si with Mg( g ) led to the formation of Mg 2 Si, and then a Mg–Si liquid that sweated away to yield free‐standing, nanocrystalline MgO‐based replicas. Such direct low‐temperature magnesiothermic conversion of diatom microshells enables the synthesis of large numbers of 3‐D nanocrystal assemblies with well‐controlled morphologies for catalytic/chemical, biological, optical, and other applications.
Characterization of the Promoter Region and 3′ End of the Human Insulin Receptor Gene (1989)

The insulin receptor is an essential protein present on the surface of virtually all cells. Little is known about the control of the level of this protein on cellular surfaces, but it has been found that the level of insulin receptor protein correlates roughly with the level of insulin receptor (IR) gene transcripts within cells. Although the protein-encoding region is only about 4000 base pairs (bps), there are multiple species of IR mRNA ranging in size from 5400 to 9400 bps. We have found that the variation in size of these transcripts is due to multiple 3' ends, presumably reflecting alternative polyadenylation, so that the final IR exon ranges in size from 1400 to 5400 bps. The IR gene promoter is like other housekeeping promoters in that it has no TATA or CAAT boxes, is extremely GC-rich, and has multiple transcriptional initiation sites primarily within a 300-bp GC-rich region. Reporter gene analysis using IR promoter-chloramphenicol acetyltransferase (HIRcat) fusion plasmids established regions responsible for promoter activity and verified the localization of the major IR gene transcriptional initiation sites. However, transfection with HIRcat plasmids containing regions from -153 to -1818 resulted in increased utilization of the most 5' IR gene mRNA initiation sites in transfected relative to untransfected cells. Reporter gene analysis also established that a region of the IR promoter and first exon containing all of the transcriptional initiation sites is more active in HepG2 than CV1 cells. Because the steady-state level of expression of the IR gene is much higher in HepG2 than CV1 cells, the results of the reporter gene analysis may reflect tissue-specific differences in IR gene transcription. Such tissue-specific transcriptional regulation would be a novel finding in a housekeeping promoter.
Coordination Chemistry of Silver Cations (2002)

While in pure solvents Ag(+) is known to be tetrahedrally coordinated, in the presence of ligands such as ammonia it forms linear complexes, usually explained by the ion's tendency toward sd-hybridization. To explore this disparity, we have investigated the reaction of ammoniated silver cations Ag(+)(NH(3))(n)(), n = 11-23, with H(2)O as well as the complementary process, the reaction of Ag(+)(H(2)O)(n)(), n = 25-45, with NH(3) by means of FT-ICR mass spectrometry. In both cases, ligand exchange reactions take place, leading to clusters with a limited number of NH(3) ligands. The former reaction proceeds very rapidly until only three NH(3) ligands are left, followed by a much slower loss of an additional ligand to form Ag(+)(NH(3))(2)(H(2)O)(m)() clusters. In the complementary process, the reaction of Ag(+)(H(2)O)(n)() with NH(3) five ammonia ligands are very rapidly taken up by the clusters, with a much less efficient uptake of a sixth one. The accompanying DFT calculations reveal a delicate balance between competing effects where not only the preference of Ag(+) for sd-hybridization, but also its ability to polarize the ligands and thus affect the strength of their hydrogen bonding, as well as the ability of the solvent to form extended hydrogen-bonded networks are important.
ChemInform Abstract: Substituted γ‐Lactones. Part 38. Structural Elucidation of the Reaction Products from 4‐Aroyl‐3‐hydroxy‐2(5H)‐furanones and 1,2‐ Diamines. (1992)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
CD40-CD40 ligand interactions in experimental allergic encephalomyelitis and multiple sclerosis. (1996)

We investigated the role of CD40-CD40 ligand (CD40L) interactions in multiple sclerosis (MS) and experimental allergic encephalomyelitis (EAE). Activated helper T cells expressing CD40L (gp39) surface protein were found in MS patient brain sections, but not in brain tissue sections of normal controls or patients with other neurological disease. CD40L-positive cells were co-localized with CD40-bearing cells in active lesions (perivascular infiltrates). Most of these CD40-bearing cells proved to be of the monocytic lineage (macrophages or microglial cells), and relatively few were B cells. To functionally evaluate CD40-CD40L interactions, EAE was elicited in mice by means of proteolipid-peptide immunization. Treatment with anti-CD40L monoclonal antibody completely prevented the development of disease. Furthermore, administration of anti-CD40L monoclonal antibody, even after disease onset, shortly before maximum disability score was reached led to dramatic disease reduction. The presence of helper T cells expressing CD40L in brain tissue of MS patients and EAE animals, together with the functional evidence provided by successful experimental prevention and therapy in an animal model, indicates that blockade of CD40-CD40L-mediated cellular interactions may be a method for interference in active MS.
Identification of Functional Domains of the Aryl Hydrocarbon Receptor (1995)

Functional domains of the mouse aryl hydrocarbon receptor (Ahr) were investigated by deletion analysis. Ligand binding was localized to a region encompassing the PAS B repeat. The ligand-mediated dissociation of Ahr from the 90-kDa heat shock protein (HSP90) does not require the aryl hydrocarbon receptor nuclear translocator (Arnt), but it is slightly enhanced by this protein. One HSP90 molecule appears to bind within the PAS region. The other molecule of HSP90 appears to require interaction at two sites: one over the basic helix-loop-helix region, and the other located within the PAS region. Each mutant was analyzed for dimerization with full-length mouse Arnt and subsequent binding of the dimer to the xenobiotic responsive element (XRE). In order to minimize any artificial steric hindrances to dimerization and XRE binding, each Ahr mutant was also tested with an equivalently deleted Arnt mutant. The basic region of Ahr is required for XRE binding but not for dimerization. Both the first and second helices of the basic helix-loop-helix motif and the PAS region are required for dimerization. These last results are analogous to those previously obtained for Arnt (Reisz-Porszasz, S., Probst, M.R., Fukunaga, B. N., and Hankinson, O. (1994) Mol. Cell. Biol. 14, 6075-6086) compatible with the notion that equivalent regions of Ahr and Arnt associate with each other. Deletion of the carboxyl-terminal half of Ahr does not affect dimerization or XRE binding but, in contrast to an equivalent deletion of Arnt, eliminates biological activity as assessed by an in vivo transcriptional activation assay, suggesting that this region of Ahr plays a more prominent role in transcriptional activation of the cyp1a1 gene than the corresponding region of Arnt.
Oligomerization and regioselective hydrosilylation of styrenes catalyzed by cationic allyl nickel complexes bearing allylphosphine ligands (2007)

The complexes [Ni(eta(3)-CH(2)CHCH(2))Br(kappa(1)P-PR(2)CH(2)CH=CH(2))] (R = Ph 1, (i)Pr2 ) and [Ni(eta(3)-CH(2)C(R')CH(2))(kappa(1)P-PR(2)CH(2)CH=CH(2))(2)][BAr'(4)] (R' = H, R = Ph 4a, R = (i)Pr 4b; R' = CH(3), R = Ph 5a, R = (i)Pr 5b; Ar' = 3,5-C(6)H(3)(CF(3))(2)) have been prepared and characterized. The X-ray crystal structures of 1, 2 and 5b have been determined. 4a-b and 5a-b are catalyst precursors for the oligomerization of RC(6)H(4)CH=CH(2) to oligostyrene (R = H) or oligo(4-methylstyrene) (R = CH(3)) respectively, without the need of a co-catalyst such as methylalumoxane. The catalytic activities range from moderate to high. The oligomerization reactions are carried out in the temperature interval 25-40 degrees C in 1,2-dichloroethane, using an olefin/catalyst ratio equal to 200, yielding oligostyrenes with a high isotactic fraction content P(m), with M(n) in the range 700-1900 Dalton, and polydispersities between 1.22 and 1.64. The cationic complexes 4a-b and 5a-b are also effective catalyst precursors for the hydrosilylation reactions of styrene or 4-methylstyrene with PhSiH(3) in 1,2-dichloroethane at 40 degrees C using an olefin/catalyst ratio equal to 100, leading selectively to RC(6)H(4)CH(SiH(2)Ph)CH(3) (R = H, CH(3)) in 50-79% yield.
mRNA sequences influencing translation and the selection of AUG initiator codons in the yeast Saccharomyces cerevisiae (1996)

The secondary structure and sequences influencing the expression and selection of the AUG initiator codon in the yeast Saccharomyces cerevisiae were investigated with two fused genes, which were composed of either the CYC7 or CYC1 leader regions, respectively, linked to the lacZ coding region. In addition, the strains contained the upf1-delta disruption, which stabilized mRNAs that had premature termination codons, resulting in wild-type levels. The following major conclusions were reached by measuring beta-galactosidase activities in yeast strains having integrated single copies of the fused genes with various alterations in the 89 and 38 nucleotide-long untranslated CYC7 and CYC1 leader regions, respectively. The leader region adjacent to the AUG initiator codon was dispensable, but the nucleotide preceding the AUG initiator at position -3 modified the efficiency of translation by less than twofold, exhibiting an order of preference A > G > C > U. Upstream out-of-frame AUG triplets diminished initiation at the normal site, from essentially complete inhibition to approximately 50% inhibition, depending on the position of the upstream AUG triplet and on the context (-3 position nucleotides) of the two AUG triplets. In this regard, complete inhibition occurred when the upstream and downstream AUG triplets were closer together, and when the upstream and downstream AUG triplets had, respectively, optimal and suboptimal contexts. Thus, leaky scanning occurs in yeast, similar to its occurrence in higher eukaryotes. In contrast, termination codons between two AUG triplets causes reinitiation at the downstream AUG in higher eukaryotes, but not generally in yeast. Our results and the results of others with GCN4 mRNA and its derivatives indicate that reinitiation is not a general phenomenon in yeast, and that special sequences are required.