gebhart/patrepeval huggingface dataset:
The synthesis of heterocycles via addition–elimination reactions of 4- and 5-aminoimidazoles (1992)

4-Aminoimidazoles 1 undergo addition–elimination reactions with the electrophilic reagents 5–12 to give exclusively N-adducts, which are useful intermediates for further synthetic transformations to novel heterocyclic systems. Diethyl ethoxymethylenemalonate 5 and 4-amino-1-benzylimidazole 1g give the adduct 13g and subsequent acid-catalysed cyclisation gives the imidazo[4,5-b]pyridine 25 and the heterocyclic mesomeric betaine 26 which undergoes 1,3-dipolar cycloaddition with di-methyl acetylenedicarboxylate to give two products 29 and 30. When the 2-alkyl-4-aminoimidazoles 1b–d are generated in situ in the presence of the reagent 5, significant products are the 5,5′-diimidazoles 15 and a mechanism for this novel transformation is proposed. 4-Amino-3-cyano-imidazo[1,5-a]pyrimidines 40 and 41 are formed by cyclisation of the N-adducts prepared using ethoxymethylenemalononitriles 6 and 7. Ethoxymethyleneurethane 9 gives the adducts 66 and cyclisation of the parent adduct 66a gives the novel imidazo[1,5-a]-1,3,5-triazin-4-one 68a, the potassium salt of which undergoes N-alkylation. The use of the reagents 10–12 leads to novel 4-aminoimidazo[1,5-a]-1,3,5-triazine derivatives 72 whose chemical reactions with both electrophilic and nucleophilic reagents are reported. 5-Aminoimidazoles 3 undergo addition–elimination reactions with the electrophilic reagents 5–12 to give N-adducts and/or C-adducts, depending upon the structure of the reagent. These stable addition–elimination products are usually obtained in good yield and are useful intermediates for further synthesis. Reaction of the amines 3 with diethyl ethoxymethylenemalonate 5 gives mainly N-adducts 17 which can be cyclised using phosphoryl chloride to give the versatile 7-chloroimidazo[4,5-b]pyridines 31. With ethoxymethylenemalononitrile 6 the amines 3 give C-adducts 42. Thermal cyclisation of these adducts 42 gives 5-amino-6-cyanoimidazo[4,5-b]pyridines 43 which are transformed into novel heterocyclic systems including the tricyclic imidazo[4′,5′:5,6]pyrido[2,3-d]pyrimidines 55. Cyclisation of the adducts obtained using ethoxymethyleneurethane 9 and the N-cyano analogues 10 and 12 provides new synthetic routes to amino-purine derivatives 86 and 87 and hypoxanthines 70. The preference of electrophilic reagents for N- or C-addition to 5-aminoimidazoles 3 is rationalised using Frontier Molecular Orbital theory.
Effects of 5,5′-diphenylhydantoin on the thyroid status in rats (1996)

Treatment of rats with phenytoin (DPH), an anti-epileptic drug, results in lower tissue thyroid hormone (TH) levels. To investigate if this is accompanied by tissue hypothyroidism, rats were treated for 3 weeks with DPH (50 mg/kg body wt in food). Thyroid hormone-dependent parameters were measured, and the results were compared to those of control rats and to those of athyreotic rats substituted with thyroxine + triiodothyronine (Tx + TH) to reach the same plasma TH levels as DPH-treated rats. These rats were mildly hypothyroid with regard to their TH and TSH levels and TH-dependent parameters. Both DPH and Tx + TH led to a decrease in plasma thyroxine (T4) and triiodothyronine (T3) (+/-70% of the control). The percentage free T4 was unchanged. Plasma thyrotropin (TSH) was increased only in the Tx + TH rats (sixfold). For DPH rats, pituitary hormone content was not different from the control; growth hormone was lower and TSH was higher in Tx + TH rats. In DPH and Tx + TH rats, an increase in hepatic T4 and T3 uridine-diphosphate glucuronyltransferase activity was found, likewise indicating a change in the metabolic pathway of TH. Hepatic iodothyronine deiodinase (ID) type I activity decreased in Tx + TH rats but did not alter in DPH rats. Hepatic alpha-glycerophosphate dehydrogenase (alpha-GPD) decreased in DPH and Tx + TH rats. Malic enzyme in liver was enhanced in DPH rats. In the brains of DPH rats the level of alpha-GPD activity was raised; in Tx + TH it was lowered. The ID type II activity in the brain was reduced in DPH rats, but ID type III did not change for either group. Total body oxygen consumption increased in DPH rats (13%); it decreased in Tx + TH rats (9%). Our results show that DPH causes changes comparable to mild hypothyroidism. The lack of or a diminished hypothyroid response can be explained as the attenuating agonistic effect of DPH, which is supported by O2 consumption, brain ID type II and alpha-GPD activities. The T4 content was reduced by 30% in thyroid digests; this, together with a reduced T4 secretion, can lead to serious hypothyroxinemia during prolonged DPH treatment.
[Effect of synthesized GYY4137, a slowly releasing hydrogen sulfide donor, on cell viability and distribution of hydrogen sulfide in mice]. (2010)

The new chemical compound is a relative stable, slow-releasing donor of hydrogen sulfide with low cellular toxicity, which may be used to study the regulatory role of hydrogen sulfide in the cellular physiological and pathophysiological mechanism of the animal model with acute diseases.
Preliminary experimental anticancer activity of cecropins. (1995)

The cecropins are a group of peptides that were first isolated from the hemolymph of the giant silk moth, Hyalophora cecropia. In preliminary studies, these novel peptides were shown to be active against several bacteria and mammalian lymphomas and leukemias in vitro. The mechanism of action of the cecropins is thought to involve pore formation at the cytoplasmic membrane. The potential anticancer activity of cecropin B, cecropin P1 and Shiva-1 was investigated against a panel of mammalian cell lines in vitro. Cell lines showed a range of sensitivities to cecropin B (IC50 3.2 to > 100 microM), and two cell lines with the multidrug-resistant phenotype were sensitive to the peptide. In vitro cecropin B activity was virtually complete within one hour. Preliminary in vivo studies showed that cecropin B increases the survival time of mice bearing murine ascitic colon adenocarcinoma cells. Future studies will address structure/activity relationships of similar peptides in order to optimize antitumor activity.
Chemistry and Anti-Herpes Simplex virus Type 1 Evaluation of CycloSal-Nucleotides of Acyclic Nucleoside Analogues (1998)

The synthesis of different cycloSal-phosphotriesters of the acyclic nucleoside analogues acyclovir (ACV), penciclovir (PCV) and T-penciclovir (T-PCV) as potential new lipophilic, membrane-soluble pronucleotides is described. The introduction of the cycloSal moiety was achieved by using reactive cyclic chlorophosphane reagents. In addition to the cycloSal-PCV monophosphate (MP) phosphotriesters, a second derivative bearing an acetyl group at the second primary alcohol function was prepared. In hydrolysis studies the cycloSal-ACVMPs showed the expected range of hydrolytic stability dependent on the substituent in the masking group (8-17 h). In contrast, the cycloSal-PCVMP derivatives exhibited a 11- to 15-fold increase in hydrolytic lability as compared to the corresponding cycloSal-ACVMP derivatives. We demonstrated that the free primary alcohol group is responsible for this rate acceleration because cycloSal-OAc-PCVMP, in which the hydroxyl group was blocked by acetylation, did not show the aforementioned acceleration. Unexpectedly, the hydrolysis product was not PCVMP but according to NMR and mass spectrometry it was cycloPCVMP (cPCVMP). The title compounds were evaluated in vitro for their ability to inhibit herpes simplex virus type 1 (HSV-1) and thymidine kinase-negative (TK-) HSV-1 replication in Vero cells. The cycloSal-ACVMP compounds exhibited high antiviral activity in HSV-1-infected cells. More importantly, one derivative retained all activity from the wild-type virus strain in HSV-1/TK(-)-infected Vero cells. The PCV derivatives were markedly less active. The reason for the failure of the cycloSal-PCVMPs seems to be due to the formation of cPCVMP instead of the desired PCVMP.
A GH3-like Domain in Reaper Is Required for Mitochondrial Localization and Induction of IAP Degradation (2003)

Reaper is a potent pro-apoptotic protein originally identified in a screen for Drosophila mutants defective in apoptotic induction. Multiple functions have been ascribed to this protein, including inhibition of IAPs (inhibitors of apoptosis); induction of IAP degradation; inhibition of protein translation; and when expressed in vertebrate cells, induction of mitochondrial cytochrome c release. Structure/function analysis of Reaper has identified an extreme N-terminal motif that appears to be sufficient for inhibition of IAP function. We report here that this domain, although required for IAP destabilization, is not sufficient. Moreover, we have identified a small region of Reaper, similar to the GH3 domain of Grim, that is required for localization of Reaper to mitochondria, induction of IAP degradation, and potent cell killing. Although a mutant Reaper protein lacking the GH3 domain was deficient in these properties, these defects could be fully rectified by appending either the C-terminal mitochondrial targeting sequence from Bcl-xL or a homologous region from the pro-apoptotic protein HID. Together, these data strongly suggest that IAP destabilization by Reaper in intact cells requires Reaper localization to mitochondria and that induction of IAP instability by Reaper is important for the potent induction of apoptosis in Drosophila cells.
Compression of optical pulses to six femtoseconds by using cubic phase compensation (1987)

We demonstrate that a combination of prisms and diffraction gratings can provide not only quadratic but also cubic phase compensation of ultrashort optical pulses. We obtain compressed pulses as short as 6 fsec.
Sorghum (<i>Sorghum bicolor</i> L.) (2006)

This chapter describes a stepwise protocol for Agrobacterium-mediated sorghum genetic transformation. Immature embryos from sorghum plants were used as the target explants. The Agrobacterium strain LBA4404, carrying a "super-binary" vector, was used in this protocol. Agrobacterium co-transformation vectors, one T-DNA containing the selectable marker gene and another T-DNA containing the trait gene(s), were also introduced in sorghum transformation for eliminating the selectable marker gene in the resulting transgenic plants. This chapter provides recommendations for analysis of the transgenic plants to confirm T-DNA integration into the sorghum genome and segregation of the selectable marker gene from the trait gene(s).
[Effect of a helium-neon laser on cellular growth: an in vitro study of human gingival fibroblasts]. (1988)

For a better understanding of the clinical effects obtained with lasers of low power on oral wounds, an in vitro study was conducted on human fibroblasts obtained from a primary gingival culture in order to evaluate the effect of one or several irradiations obtained with a Helium-neon laser (632.8 nm, 10 mW). An irradiation of 10 minutes (1.2J/cm2) induced a growth acceleration of the cellular population compared to a non-irradiated control population. The greatest effect was obtained four days after treatment. Furthermore, if the cells were submitted to repeated irradiations every four days, the cellular divisions increased after each treatment. A careful interpretation of these in vitro results on healing time of oral wounds in vivo would suggest that it may be due partly to a recycling actin of low power lasers on resting cells.
Introduction to Particle Accelerators and their Limitations (2016)

The paper gives an overview of the principles of particle accelerators and their historical development. After introducing the basic concepts, the main emphasis is on sketching the layout of modern storage rings and discussing their limitations in terms of energy and machine performance. Examples of existing machines, among them the Large Hadron Collider (LHC) at CERN, demonstrate the basic principles of and the technical and physical limits that we face in the design and operation of particle colliders. The push for ever higher beam energies motivates the design of future colliders as well as the development of more efficient acceleration techniques.
Survey of reasons for extraction of permanent teeth in Italy (1996)

The purpose of the study is to collect information on the reasons given by dentists, randomly selected from the Italian Dental and Maxillo-Facial Association's, for extracting permanent teeth in Italy. From the 164 dentists responding, 1056 teeth in 839 patients were extracted during two weeks of working activity. More than two-thirds of the teeth were extracted for dental caries (34.4%) and periodontal disease (33.1%). The mean number of teeth extracted per patient showed a significant increasing trend with increasing age, being 1.09 in those from 16 to 39 yr, 1.25 in the 40-59-yr-old group, to 1.54 in those over 59 yr of age (F = 21.44; P < 0.0001). The third molar was the most frequently extracted tooth and 41.3% were removed due to impaction reasons, in particular from the mandible. The first and second molars and the premolars were extracted most often because of caries; more than half of the incisors and the canines were extracted for periodontal reasons; the majority of the teeth removed for prosthetic reasons, 57.1%, were incisors and canines, especially in the mandible; of the teeth extracted for orthodontic reasons, 47.4% were first and second premolars. The prevalence of subjects with at least one tooth extracted for dental caries and for orthodontic reasons were respectively significantly higher in the irregular than the regular attenders (chi-square = 46.55; P < 0.0001), and in the regular than the irregular dental attenders (chi-square = 63.12; P < 0.0001). Dental practitioners should promote targeted initiatives for prevention and treatment of diseases in order to reduce in particular the incidence of tooth extraction because of caries and periodontal disease.
A matter of ethics (2011)

The observance and application of ethics within the business world is not something new. For as long as mankind has been living in groups, the moral regulation of behaviour has been necessary for the group's wellbeing. The ancient Greeks recognised principles or standards of human conduct (ethika) while the Romans coined the concept of 'mores' from which morals and customs evolved (Fox - A Guide to Public Ethics).
High Speed Quantum Key Distribution Over Optical Fiber Network System (2009)

The National Institute of Standards and Technology (NIST) has developed a number of complete fiber-based high-speed quantum key distribution (QKD) systems that includes an 850 nm QKD system for a local area network (LAN), a 1310 nm QKD system for a metropolitan area network (MAN), and a 3-node quantum network controlled by a network manager. This paper discusses the key techniques used to implement these systems, which include polarization recovery, noise reduction, frequency up-conversion detection based on a periodically polled lithium nitrate (PPLN) waveguide, custom high-speed data handling boards and quantum network management. Using our quantum network, a QKD secured video surveillance application has been demonstrated. Our intention is to show the feasibility and sophistication of QKD systems based on current technology.
Oxidized Low Density Lipoproteins in Patients With Transplant-Associated Coronary Artery Disease (1998)

The monoclonal antibody 4E6-based ELISA was used to quantify levels of oxidized LDL in plasma of 65 control subjects, 47 patients transplanted for dilated cardiomyopathy (DCM), and 60 patients transplanted for coronary artery disease (CAD). Levels of oxidized LDL were 0.68+/-0.039 mg/dL (mean+/-SEM), 1.27+/-0.14 mg/dL (P<.001 versus control), and 1.73+/-0.13 mg/dL (P<.001 versus control and <0.01 versus DCM), respectively. Levels of oxidized LDL were significantly lower in transplanted patients with angiographically normal coronary arteries (grade 0, 1.16+/-0.053 mg/dL; n=79) than in patients with mild (grade 1, 2.13+/-0.30 mg/dL; n=18; P<.001 versus grade 0) or severe (grade 2, 3.18+/-0.45 mg/dL; n=10; P<.001 versus grade 0 and P<.05 versus grade 1) coronary artery stenosis. Logistic regression analysis identified three parameters that were significantly and independently correlated with posttransplant CAD: plasma levels of oxidized LDL (P=.0001), length of follow-up (P=.0008), and donor age (P=.047). Thus, the present study demonstrates that plasma levels of oxidized LDL correlate with the extent of CAD in heart transplant patients and suggests that elevated levels of oxidized LDL may be a marker for CAD.
Overexpressing a NAM, ATAF, and CUC (NAC) transcription factor enhances drought resistance and salt tolerance in rice (2006)

Drought and salinity are major abiotic stresses to crop production. Here, we show that overexpression of stress responsive gene SNAC1 (STRESS-RESPONSIVE NAC 1) significantly enhances drought resistance in transgenic rice (22-34% higher seed setting than control) in the field under severe drought stress conditions at the reproductive stage while showing no phenotypic changes or yield penalty. The transgenic rice also shows significantly improved drought resistance and salt tolerance at the vegetative stage. Compared with WT, the transgenic rice are more sensitive to abscisic acid and lose water more slowly by closing more stomatal pores, yet display no significant difference in the rate of photosynthesis. SNAC1 is induced predominantly in guard cells by drought and encodes a NAM, ATAF, and CUC (NAC) transcription factor with transactivation activity. DNA chip analysis revealed that a large number of stress-related genes were up-regulated in the SNAC1-overexpressing rice plants. Our data suggest that SNAC1 holds promising utility in improving drought and salinity tolerance in rice.
SPICE: A Guide to Circuit Simulation and Analysis Using PSpice (1988)

From the Publisher:
Revision of best-selling guide to the PSpice circuit simulator by an authoritative author. Provides a tutorial approach to using PSpice through graduated examples. Comprehensive coverage of the newest capabilities of this program. Explains the use of Monte Carlo methods in PSpice for statistically computing estimates of how circuits will behave with variations in component values. Explains the use of sensitivity calculations and worst case analysis in PSpice for discovering the maximum range of circuit performance and the causes of extreme operations. Two-Port Network Analysis, explains derivation and use of two-port parameters, including s-parameters.
An Inhibitor of Endopeptidase‐24.15 Blocks the Degradation of Intraventricularly Administered Dynorphins (1990)

Conversion of the octapeptide dynorphin (Dyn) A-(1-8) to Leu5-enkephalin (LE) by endopeptidase EC 3.4.24.15 (EP-24.15) in vivo was examined using the technique of ventriculocisternal perfusion. Peptides were administered intracerebroventricularly in the presence or absence of the EP-24.15 inhibitor N-[1-(R,S)-carboxy-3-phenylpropyl]-Ala-Ala-Phe-p-aminobenzoate (cFPAAF-pAB) via cannulae placed into the lateral ventricle of urethane-anesthetized rats. The concentration of Dyn-like peptides and LE within the CSF was monitored by radioimmunoassay in samples of CSF taken from a second cannula placed in the cisterna magna. In the absence of inhibitor, less than 5% of the Dyn A-(1-8) administered was recovered in CSF. Immunoreactive LE, which is normally not found in CSF, increased rapidly in content following Dyn A-(1-8) infusion, an observation suggesting that the larger peptide is converted to LE. When the inhibitor cFPAAF-pAB was coadministered with Dyn A-(1-8), the concentration of immunoreactive Dyn A-(1-8) after 5 min was 40 times higher than that found in the absence of inhibitor. The angiotensin converting enzyme inhibitor captopril reduced the degradation of Dyn A-(1-8) to a much lesser degree. The inhibitor of EP-24.15 also afforded some protection of other Dyn-like peptides. No EP-24.15 activity was found in rat CSF, whereas high activity was found in the choroid plexus. Taken together, these data clearly indicate that an ectoenzyme form of EP-24.15 rapidly converts intracerebroventricularly administered Dyn-like peptides to LE.
Catalytic Asymmetric Synthesis of Diarylacetates and 4,4-Diarylbutanoates. A Formal Asymmetric Synthesis of (+)-Sertraline (2000)

ADVERTISEMENT RETURN TO ISSUEPREVAdditions & Corr...Additions & CorrectionsORIGINAL ARTICLEThis notice is a correctionCatalytic Asymmetric Synthesis of Diarylacetates and 4,4-Diarylbutanoates. A Formal Asymmetric Synthesis of (+)-SertralineHuw M. L. Davies, Douglas G. Stafford, and Tore HansenCite this: Org. Lett. 2000, 2, 3, 417Publication Date (Web):January 7, 2000Publication History Published online7 January 2000Published inissue 1 February 2000https://pubs.acs.org/doi/10.1021/ol9903943https://doi.org/10.1021/ol9903943correctionACS PublicationsCopyright © 2000 American Chemical Society. This publication is available under these Terms of Use. Request reuse permissions This publication is free to access through this site. Learn MoreArticle Views883Altmetric-Citations1LEARN 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 PDF (7 KB) Get e-AlertscloseSUBJECTS:Enantioselective synthesis,Theoretical and computational chemistry Get e-Alerts
Online Driver Distraction Detection Using Long Short-Term Memory (2011)

Lane-keeping assistance systems for vehicles may be more acceptable to users if the assistance was adaptive to the driver's state. To adapt systems in this way, a method for detection of driver distraction is needed. Thus, we propose a novel technique for online detection of driver's distraction, modeling the long-range temporal context of driving and head tracking data. We show that long short-term memory (LSTM) recurrent neural networks enable a reliable subject-independent detection of inattention with an accuracy of up to 96.6%. Thereby, our LSTM framework significantly outperforms conventional approaches such as support vector machines (SVMs).
Structure and Function of the p53 Tumor Suppressor Gene: Clues for Rational Cancer Therapeutic Strategies (1996)

The p53 tumor suppressor protein is involved in multiple central cellular processes, including transcription, DNA repair, genomic stability, senescence, cell cycle control, and apoptosis. p53 is functionally inactivated by structural mutations, interaction with viral products, and endogenous cellular mechanisms in the majority of human cancers. This functional inactivation can, in some circumstances, produce resistance to DNA-damaging agents commonly used in cancer chemotherapy and radiotherapeutic approaches. Current research is defining the biochemical pathways through which p53 induces cell cycle arrest and apoptosis. Knowledge of these fundamental processes is leading to the identification of molecular targets toward which multimodality cancer therapies, using chemotherapeutic, immunotherapeutic, and gene-therapeutic strategies, can be based.