gebhart/patrepeval huggingface dataset:
Substrate Specificity and Stereoselectivity of Rat Brain Microsomal Anandamide Amidohydrolase (1999)

Anandamide amidohydrolase (AAH) catalyzes the hydrolysis of arachidonylethanolamide (anandamide), an endogenous cannabinoid receptor ligand. To delineate the structural requirements of AAH substrates, rat brain microsomal AAH hydrolysis of a series of anandamide congeners was studied using two reverse-phase high-performance liquid chromatography (RP-HPLC) assays developed in our laboratory. Arachidonamide (1) was found to be the best substrate with an apparent Km of 2.34 mM and a Vmax of 2.89 nmol/min/mg of protein. Although anandamide (2) has a similar Km value, its Vmax is approximately one-half that of arachidonamide. N, N-Bis(2-hydroxyethyl)arachidonamide (3) was not hydrolyzed, suggesting specificity for unsubstituted or mono-N-substituted arachidonamides. Analogues with a methyl group at the 1'-position of the ethanolamido headgroup were also found to have greater resistance to enzymatic turnover and therefore increased metabolic stability. The enzyme exhibited high stereoselectivity as the rate of hydrolysis of (R)-alpha-methanandamide (2.4%) (anandamide = 100%) was about 10-fold lower than that of its (S)-enantiomer (23%). In contrast, (R)-beta-methanandamide was 6-times more susceptible (121%) than the (S)-beta-enantiomer (21%). Interestingly, an inverse correlation was shown between AAH stereoselectivity and the brain cannabinoid receptor affinity as the enantiomers with high receptor affinity displayed low susceptibility to hydrolysis by AAH. Metabolic stability is also imparted to analogues with a short hydrocarbon headgroup as well as to those possessing 2-monomethyl or 2,2-dimethyl substituents. 2-Arachidonylglycerol and racemic 1-arachidonylglycerol were shown to be excellent AAH substrates. To identify AAH inhibitors, hydrolysis of anandamide was also studied in the presence of a select group of cannabimimetics. Of these, (-)-Delta8-THC and SR141716A, a biarylpyrazole CB1 antagonist, were found to inhibit enzymatic activity. These newly defined enzyme recognition parameters should provide a foundation for the rational development of stable, therapeutically useful anandamide analogues with high receptor affinity.
Characterization of an alpha 1—-3-galactosyltransferase homologue on human chromosome 12 that is organized as a processed pseudogene. (1991)

UDP-Gal:Gal beta 1----4GlcNAc alpha 1----3-galactosyltransferase is a terminal glycosyltransferase that is widely expressed in a variety of mammalian species, with the notable exception of man, apes, and Old World monkeys. We recently reported the isolation of a bovine cDNA clone that contains the complete coding sequence for this enzyme (Joziasse, D. H., Shaper, J. H., Van den Eijnden, D. H., Van Tunen, A. J., and Shaper, N. L. (1989) J. Biol. Chem. 264, 14290-14297). Using this cDNA as a probe, we have demonstrated that, although transcripts cannot be detected in a variety of established human cell lines by Northern blot analysis, homologous sequences are present in human genomic DNA. To establish that these sequences represent a human homologue of alpha 1----3-galactosyltransferase, we have used the bovine cDNA as a probe to isolate two nonoverlapping clones (HGT-2 and HGT-10) from a human genomic DNA library. Clone HGT-2 contains a 1.5-kilobase uninterrupted linear sequence similar to bovine alpha 1----3-galactosyltransferase that is organized as a processed pseudogene. This sequence, flanked by Alu type repeats, contains a short 5'- and 3'-untranslated region and a complete recognizable coding region that is 81% similar at the nucleotide level to bovine alpha 1----3-galactosyltransferase. This putative coding region contains multiple frameshift mutations and nonsense codons in all three reading frames which precludes the synthesis of a functional enzyme. Nevertheless, after optimal alignment, translation predicts a polypeptide that is 68% similar at the amino acid level to the bovine enzyme. Based on Southern analysis and limited sequence analysis, clone HGT-10 contains coding sequences similar to the NH2-terminal region of bovine alpha 1----3-galactosyltransferase. By analysis of panels of human-rodent somatic cell hybrids we have established that the nonfunctional, processed pseudogene and the human homologue represented by HGT-10 are located on human chromosomes 12 and 9, respectively. Interestingly, a comparison of the predicted amino acid sequence of the carboxyl-terminal two-thirds of human alpha 1----3-galactosyltransferase, with the corresponding region of the human blood group A, UDP-GalNAc:[Fuc alpha 1----2]Gal beta 1----4GlcNAc alpha 1----3-GalNAc-transferase (Yamamoto, F., Marken, J., Tsuji, T., White, T., Clausen, H., and Hakomori, S. (1990a) J. Biol. Chem. 265, 1146-1151), reveals a significant similarity (39%) suggesting that these two enzymes may have arisen from the same ancestral gene as a result of gene duplication and subsequent divergence.
Indoleamine 2,3-dioxygenase is a signaling protein in long-term tolerance by dendritic cells (2011)

Regulation of tryptophan metabolism by indoleamine 2,3-dioxygenase (IDO) in dendritic cells (DCs) is a highly versatile modulator of immunity. In inflammation, interferon-γ is the main inducer of IDO for the prevention of hyperinflammatory responses, yet IDO is also responsible for self-tolerance effects in the longer term. Here we show that treatment of mouse plasmacytoid DCs (pDCs) with transforming growth factor-β (TGF-β) conferred regulatory effects on IDO that were mechanistically separable from its enzymic activity. We found that IDO was involved in intracellular signaling events responsible for the self-amplification and maintenance of a stably regulatory phenotype in pDCs. Thus, IDO has a tonic, nonenzymic function that contributes to TGF-β-driven tolerance in noninflammatory contexts.
A predefined command recognition system using a ceiling microphone array in noisy housing environments (2008)

This paper describes a speech recognition system that detects basic voice commands for a mobile robot operating in a home space. The system recognizes arbitrary timed speech with position information in a noisy housing environment. The microphone array is attached to the ceiling, and localizes sound source direction in azimuth and elevation, then separates multiple sound sources using delay and sum beam forming (DSBF) and frequency band separation (FBS) algorithm. We implement the sound localization and separation method on our 32 channel microphone array. The separated sound source is recognized using an open source speech recognizer. These sound localization, separation and recognition functions are implemented as online processing in real world. We define four indices to evaluate the performance of the recognition system, and the efficiency in a noisy environment or with distant sound sources is confirmed from experiments in varied conditions. Finally, an application for a mobile robot interface is reported.
Fatty acyl moieties: improving Pro‐rich peptide uptake inside HeLa cells (2005)

In the field of drug delivery there has been a continuous study of powerful delivery systems to aid non permeable drugs in reaching their intracellular target. Among the systems explored are cell penetrating peptides (CPPs), which first garnered interest a decade ago when the interesting translocation properties of the pioneer CPPs Tat and Antp were described. A new family of CPPs has recently been described as non cytotoxic Pro-rich vectors with favorable profiles for internalization in HeLa cells. Fatty acyl moieties that can tune a peptide's interaction with the lipophilic environment of a cell membrane have been incorporated into the Pro-rich sequence. Improvements in cellular uptake of peptides modified with fatty acyl groups, as studied by confocal microscopy and flow cytometry, as well as the results obtained by the interaction of these peptides with a model dioleoylphosphatidylcholine (DOPC) membrane and transmission electron microscopy (TEM), illustrate the importance of the fatty acyl moieties for efficient internalization.
IL-6 Produced by Kupffer Cells Induces STAT Protein Activation in Hepatocytes Early During the Course of Systemic Listerial Infections (1998)

Kupffer cells were the principal source of IL-6 produced in the livers of mice following i.v. inoculation of Listeria monocytogenes. IL-6 mRNA expression and the production of IL-6 were reduced drastically within the nonparenchymal liver cell population derived from mice rendered Kupffer cell depleted by pretreatment with liposome-encapsulated dichloromethylene diphosphonate. A sharp increase in the appearance of activated STAT3 occurred in extracts of purified hepatocytes derived from normal mice infected i.v. with Listeria. Remarkably, the kinetics of this increase overlapped IL-6 mRNA expression by Kupffer cells; each peaked at approximately 30 min postinfection. No increase in STAT3 activation was observed in IL-6-deficient or Kupffer cell-depleted animals. The results of these experiments indicate that the synthesis of IL-6 and the activation of STAT3 within hepatocytes are critical functions of Kupffer cells occurring very early during the course of systemic listerial infections.
Retroviral vector-mediated gene transfer of antisense cyclin G1 (CYCG1) inhibits proliferation of human osteogenic sarcoma cells. (1995)

Genetic changes found in human osteogenic sarcoma cells, including loss of the p53 and Rb tumor suppressor elements and overexpression of the cyclin G1 (CYCG1) proto-oncogene, suggest the potential of gene transfer as a treatment for metastatic disease. In this study, we examined the effects of antisense cyclin G1, in comparison with antisense cyclin D1 (CYCD1) and enforced expression of the universal cyclin-dependent kinase inhibitor p21WAF1/CIP1 on the proliferation of human MG-63 osteosarcoma cells. Retroviral vectors bearing antisense CYCG1 as well as antisense CYCD1 and WAF1/CIP1 (in sense orientation) driven by the Moloney murine leukemia virus long terminal repeat promoter inhibited the growth and/or survival of transduced MG-63 cells in 2-7 day cultures. This represents the first demonstration that cyclin G1 is essential for the survival and/or growth of human osteosarcoma cells. Cytostatic and cytopathic effects were accompanied by a significant increase in the incidence of apoptosis, as determined by immunocytochemical analysis of DNA fragmentation. Furthermore, transduction of MG-63 cells with a retroviral vector bearing the suicide gene, herpes simplex thymidine kinase (HStk), induced cell death on treatment with ganciclovir, exhibiting pronounced bystander effects. Taken together, the data affirm the feasibility of modulating inducible cell cycle control enzymes as a potential gene therapy approach in the clinical management of osteogenic sarcoma.
Thermal rearrangement of allyl substituted 2H-azirines to 3-azabicyclo[3.1.0]hex-2-enes (1976)

ADVERTISEMENT RETURN TO ISSUEPREVArticleThermal rearrangement of allyl substituted 2H-azirines to 3-azabicyclo[3.1.0]hex-2-enesAlbert Padwa and Per H. J. CarlsenCite this: J. Org. Chem. 1976, 41, 1, 180–182Publication Date (Print):January 1, 1976Publication History Published online1 May 2002Published inissue 1 January 1976https://doi.org/10.1021/jo00863a054Request reuse permissionsArticle Views65Altmetric-Citations15LEARN 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 InReddit PDF (319 KB) Get e-Alertsclose Get e-Alerts
Utility of an improved model of amyloid-beta (Aβ1-42) toxicity in Caenorhabditis elegans for drug screening for Alzheimer’s disease (2012)

This C. elegans model of full length Aß₁₋₄₂ expression can now be adopted for use in screens to rapidly identify and assist in development of potential therapeutics and to study underlying toxic mechanism(s) of Aß.
A novel approach to cancer immunotherapy: tumor cells decorated with CD80 generate effective antitumor immunity. (2003)

Malignant cells often elude the immune system by lacking costimulatory signals required for the generation of effective antitumor immunity. Immunization with tumor cells genetically modified to express costimulatory molecules is a highly promising approach to cancer immunotherapy. However, genetic modification of tumor cells is not only labor/time intensive but is also less efficient and bears safety concerns. To override these complications, we have recently developed a novel technology that allows for efficient and durable display of exogenous proteins on the surface of a cell within 2 h. This technology involves modification of the cell membrane with a biotin derivative and decoration of biotinylated cells with proteins chimeric with core streptavidin. A chimeric molecule composed of the extracellular domains of the human CD80 costimulatory molecule and core streptavidin (CD80-SA) was efficiently displayed on the cell surface, where it persisted with a t(1/2) of >10 days in vivo. Tumors from patients with advanced stage gynecologic cancers decorated with CD80-SA elicited potent ex vivo tumor-specific proliferative and cytotoxic responses in autologous lymphocytes. Immunization with tumor cells decorated with CD80-SA completely prevented tumor growth in an aggressive model of mouse lymphoma. This technology may serve as a fast, efficient, and safe alternative to gene transfer approaches for engineering tumor cells for use in immunotherapy and research.
Physiopathological significance of distortion-product otoacoustic emissions at 2 f1–f2 produced by high- versus low-level stimuli (2003)

Distortion product otoacoustic emissions emitted by the cochlea at 2f1-f2 in response to pairs of pure tones at f1 and f2 (DPOAE) form a class of otoacoustic emissions and as such, are viewed as a reliable tool for screening outer hair cell (OHC) dysfunctions on a pass/fail basis. However, the persistence of residual DPOAEs from impaired cochleae at high stimulus levels has suggested that above 60-70 dB SPL, instead of reflecting "active" cochlear motion, DPOAEs might represent another "passive" modality: they would thus become unsuitable for analyzing cochlear function. The present work reports the consequences on high- vs low-level DPOAEs of three types of cochlear impairments involving OHCs: progressive OHC degeneration of genetic origin in CD1 mice, complete cochlear ischemia in gerbils, and furosemide injection vs ischemia-reperfusion in gerbils. An alternative to the "active-passive" model was used wherein regardless of stimulus level, cubic DPOAEs are produced by N (probably OHC-borne) nonlinear elements driven by input I and modulated by a function F3 of their operating point o; thus, DPOAE proportional to NI3F3(o). When OHCs degenerated, thereby implying a decrease of N, DPOAE levels also decreased regardless of the stimulus level up to 80 dB SPL, in line with the previous formula but at variance with the prediction of the active-passive concept. Instead of affecting N, the other two experiments impaired the efficiency of the cochlear feedback loop as a result of its electrical drive being decreased by strial dysfunction. As it is well accepted that the impaired basilar-membrane motion, although greatly reduced at low levels, tends to catch up with a normal one at higher levels, it was assumed the same was true with I so that DPOAE levels had to be, and indeed were little affected at high levels while plummeting at low levels, without any need for invoking two modalities for DPOAE generation. Finally, comparisons of furosemide vs ischemia effects revealed additional influences on DPOAEs, possibly accounted for by function F3(o). These results lead to the proposal that although high-level DPOAEs are expected to be poor audiometric indicators, they seem well adapted to assessing the functional integrity of nonlinear elements in OHCs, i.e., presumably their mechanoelectrical transduction channels.
Dynamic control to improve the separation performance in capillary electrophoresis (1995)

Dynamic control in capillary electrophoresis (CE) is able to provide better resolution, shorter separation time, reduced band broadening and better reproducibility for the separations of organic and inorganic ions and large molecules such as proteins and DNA. This article provides an overview of dynamic control in CE by several techniques: pH, temperature, external electric field, and field amplification. These techniques take advantage of the changes in electroosmotic flow coefficient, electrophoretic mobilities of the analytes due to changes in equilibrium, viscosity of the buffer solution, and/or electric field strength. The basic theories and applications to the improvement of the separation performance for standard samples in CE by using these dynamic control techniques are presented. Finally, the advantages and shortcomings of these techniques and the future trends of dynamic control for the separations of real samples are discussed.
The Chemical Interplay between Nitric Oxide and Mitochondrial CytochromecOxidase: Reactions, Effectors and Pathophysiology (2012)

Nitric oxide (NO) reacts with Complex I and cytochrome c oxidase (CcOX, Complex IV), inducing detrimental or cytoprotective effects. Two alternative reaction pathways (PWs) have been described whereby NO reacts with CcOX, producing either a relatively labile nitrite-bound derivative (CcOX-NO(2) (-), PW1) or a more stable nitrosyl-derivative (CcOX-NO, PW2). The two derivatives are both inhibited, displaying different persistency and O(2) competitiveness. In the mitochondrion, during turnover with O(2), one pathway prevails over the other one depending on NO, cytochrome c(2+) and O(2) concentration. High cytochrome c(2+), and low O(2) proved to be crucial in favoring CcOX nitrosylation, whereas under-standard cell-culture conditions formation of the nitrite derivative prevails. All together, these findings suggest that NO can modulate physiologically the mitochondrial respiratory/OXPHOS efficiency, eventually being converted to nitrite by CcOX, without cell detrimental effects. It is worthy to point out that nitrite, far from being a simple oxidation byproduct, represents a source of NO particularly important in view of the NO cell homeostasis, the NO production depends on the NO synthases whose activity is controlled by different stimuli/effectors; relevant to its bioavailability, NO is also produced by recycling cell/body nitrite. Bioenergetic parameters, such as mitochondrial ΔΨ, lactate, and ATP production, have been assayed in several cell lines, in the presence of endogenous or exogenous NO and the evidence collected suggests a crucial interplay between CcOX and NO with important energetic implications.
A revised mechanism for the Mitsunobu reaction (1987)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA revised mechanism for the Mitsunobu reactionMario Varasi, Keith A. M. Walker, and Michael L. MaddoxCite this: J. Org. Chem. 1987, 52, 19, 4235–4238Publication Date (Print):September 1, 1987Publication History Published online1 May 2002Published inissue 1 September 1987https://pubs.acs.org/doi/10.1021/jo00228a016https://doi.org/10.1021/jo00228a016research-articleACS PublicationsRequest reuse permissionsArticle Views3165Altmetric-Citations109LEARN 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 Get e-Alerts
cGMP‐mediated phosphorylation of heat shock protein 20 may cause smooth muscle relaxation without myosin light chain dephosphorylation in swine carotid artery (2000)

Nitrovasodilators such as nitroglycerine, via production of nitric oxide and an increase in [cGMP], can induce arterial smooth muscle relaxation without proportional reduction in myosin light chain (MLC) phosphorylation or myoplasmic [Ca2+]. These findings suggest that regulatory systems, other than MLC phosphorylation and Ca2+, partially mediate nitroglycerine-induced relaxation. In swine carotid artery, we found that a membrane-permeant cGMP analogue induced relaxation without MLC dephosphorylation, suggesting that cGMP mediated the relaxation. Nitroglycerine-induced relaxation was associated with a reduction in O2 consumption, suggesting that the interaction between phosphorylated myosin and the thin filament was inhibited. Nitroglycerine-induced relaxation was associated with a 10-fold increase in the phosphorylation of a protein on Ser16. We identified this protein as heat shock protein 20 (HSP20), a member of a family of proteins known to bind to thin filaments. When homogenates of nitroglycerine-relaxed tissues were centrifuged at 6000 g, phosphorylated HSP20 preferentially sedimented in the pellet, suggesting that phosphorylation of HSP20 may increase its affinity for the thin filament. We noted that a domain of HSP20 is partially homologous to the 'minimum inhibitory sequence' of skeletal troponin I. The peptide HSP20110-121, which contains this domain, bound to actin-containing filaments only in the presence of tropomyosin, a characteristic of troponin I. High concentrations of HSP20110-121 abolished Ca2+-activated force in skinned swine carotid artery. HSP20110-121 also partially decreased actin-activated myosin S1 ATPase activity. These data suggest that cGMP-mediated phosphorylation of HSP20 on Ser16 may have a role in smooth muscle relaxation without MLC dephosphorylation. HSP20 contains an actin-binding sequence at amino acid residues 110-121 that inhibited force production in skinned carotid artery. We hypothesize that phosphorylation of HSP20 regulates force independent of MLC phosphorylation via binding of HSP20 to thin filaments and inhibition of cross-bridge cycling.