gebhart/patrepeval huggingface dataset:
Cell-mediated immune responses to syngeneic tumors. I. Identification of two distinct CTL effector pathways which differ in antigen specificity, genetic regulation, and cell surface phenotype. (1986)

It has been demonstrated previously that draining lymph nodes (DLN) from tumor-immunized mice contain a population of lymphoid cells that are capable of differentiating into functional antitumor cytotoxic T lymphocytes (CTL) during in vitro culture. In the present studies, it was observed that DLN cells from either C57BL/10 (B10) or C3H mice that had been footpad-immunized with syngeneic tumor cells differentiated into CTL during a 4-day in vitro culture in the absence of added antigen. The specificity patterns of the CTL thus generated, however, were quite different in the two strains. DLN from B10 mice immunized with ultraviolet light-induced fibrosarcoma cells of B10 origin differentiated into CTL which were only capable of lysing target cells from the tumor used for immunization. Thus, the antitumor CTL which differentiate from B10 DLN appeared to be specific for the tumor-specific antigen (TSA) expressed by these tumor cells. In contrast, DLN from C3H mice immunized with a syngeneic ultraviolet light-induced fibrosarcoma differentiated into CTL which effectively lysed not only target cells from the immunizing tumor, but several other fibrosarcomas of both B10 and C3H origin, and which did not lyse normal nontumor targets. These C3H effectors thus appeared to be specific for a tumor-associated antigen (TAA) which is widely shared by a number of tumors. Cold target-blocking studies demonstrated that the CTL generated by C3H DLN cells contained a subpopulation of TSA-specific cells in addition to cross-reactive TAA-specific effectors. (B6 X C3H)F1 (B6C3F1) mice generated cross-reactive TAA-specific CTL in response to in vivo challenge with either B10 or C3H tumors, indicating that the ability to generate a TAA-specific CTL response behaves as a dominant trait of the responding mouse strain and not as a function of the tumor used for immunization. TSA-specific CTL and cross-reactive TAA-specific CTL were distinguishable on the basis of their cell surface phenotypes, because the TSA-specific CTL generated by B10 DLN cells were Thy-1.2+ Lyt-2.2+, whereas TAA-specific B6C3F1 CTL were Thy-1.2+ Lyt-2.2-; alloantigen-specific CTL generated from the same B6C3F1 lymph nodes were Thy-1.2+ Lyt-2.2+.(ABSTRACT TRUNCATED AT 400 WORDS)
The Molecular Mechanisms of OPA1-Mediated Optic Atrophy in Drosophila Model and Prospects for Antioxidant Treatment (2008)

Mutations in optic atrophy 1 (OPA1), a nuclear gene encoding a mitochondrial protein, is the most common cause for autosomal dominant optic atrophy (DOA). The condition is characterized by gradual loss of vision, color vision defects, and temporal optic pallor. To understand the molecular mechanism by which OPA1 mutations cause optic atrophy and to facilitate the development of an effective therapeutic agent for optic atrophies, we analyzed phenotypes in the developing and adult Drosophila eyes produced by mutant dOpa1 (CG8479), a Drosophila ortholog of human OPA1. Heterozygous mutation of dOpa1 by a P-element or transposon insertions causes no discernable eye phenotype, whereas the homozygous mutation results in embryonic lethality. Using powerful Drosophila genetic techniques, we created eye-specific somatic clones. The somatic homozygous mutation of dOpa1 in the eyes caused rough (mispatterning) and glossy (decreased lens and pigment deposition) eye phenotypes in adult flies; this phenotype was reversible by precise excision of the inserted P-element. Furthermore, we show the rough eye phenotype is caused by the loss of hexagonal lattice cells in developing eyes, suggesting an increase in lattice cell apoptosis. In adult flies, the dOpa1 mutation caused an increase in reactive oxygen species (ROS) production as well as mitochondrial fragmentation associated with loss and damage of the cone and pigment cells. We show that superoxide dismutase 1 (SOD1), Vitamin E, and genetically overexpressed human SOD1 (hSOD1) is able to reverse the glossy eye phenotype of dOPA1 mutant large clones, further suggesting that ROS play an important role in cone and pigment cell death. Our results show dOpa1 mutations cause cell loss by two distinct pathogenic pathways. This study provides novel insights into the pathogenesis of optic atrophy and demonstrates the promise of antioxidants as therapeutic agents for this condition.
The biosynthesis of 8‐<i>O</i>‐methylated sialic acids in the starfish <i>Asterias rubens</i> (1998)

The unusual, 8-O-methylated sialic acids have only been found in glycoconjugates of certain species of starfish. Using a detergent-solubilised extract of a particulate fraction from gonads of Asterias rubens, a specific methylation of endogenous and exogenous glycoconjugate-bound sialic acids was detected with [14C]-S-adenosyl-L-methionine ([14C]AdoMet) as the methyl donor. For this test, a filtration assay was developed using glutardialdehyde-fixed horse erythrocyte membranes as methyl acceptor. The enzyme catalysing this reaction, the sialate-8-O-methyltransferase, was purified 22000-fold in a yield of 13% by ion-exchange chromatography and two cycles of affinity chromatography on S-adenosyl-L-homocysteine-Sepharose. Upon SDS/PAGE under reducing conditions, the purified sialate-8-O-methyltransferase revealed two bands with apparent molecular masses of 58 kDa and 62 kDa. Since no evidence for the presence of subunits was found, the relationship between these two species is unknown. The enzyme was optimally active over a broad range of pH (7.4-8.3) and at 37 degrees C. After EDTA treatment, restoration of the activity depended, in contrast to most methyltransferases, on Mn2+ or Co2+, the latter to a lesser extent. Although both, free N-acetylneuraminic acid and N-glycoloylneuraminic acid were methylated, sialic acids alpha-glycosidically bound to a number of oligosaccharides and glycoproteins were better substrates. In the presence of 20 microM AdoMet, apparent Km values of 299 microM and 44 microM were found for N-acetylneuraminic acid and N-acetylneuraminyl alpha2,3-lactose, respectively. Using N-acetylneuraminyl alpha2,3-lactose as acceptor, an apparent Km of 7.1 microM was found for S-adenosyl-L-methionine. Therefore, the sialate-8-O-methyltransferase is the first enzyme known to modify both free and glycoconjugate-bound sialic acids.
Effects of freezing, thawing, and storage of human liver samples on the microsomal contents and activities of cytochrome P450 enzymes. (1997)

Effects of freezing, thawing, and storage at room temperature of human liver samples on the contents and catalytic activities of individual forms of cytochrome P450 (P450 or CYP) were examined. The stability of liver genomic DNA was also investigated. There were no significant decreases in microsomal levels or catalytic activities of P450 enzymes by storage at -80 degrees C for 5 years. We then examined the effects of freezing/thawing of liver samples. Levels of P450 forms were determined immunochemically and by the activities of typical drug oxidation reactions in liver microsomes of human samples, which were divided into two groups. One group of samples was thawed and kept at 25 degrees C for 6 hr and then frozen again and kept for 1 week at -80 degrees C. In the other group, liver microsomes were prepared at the same time (as those from the other group), but not thawed and refrozen. Thawing the liver samples and storage for 6 hr at 25 degrees C decreased contents of total P450 by about 90% and activities of both NADH-ferricyanide and NADPH-cytochrome c reductases by about 80%. However, the decrease in b5 levels was only about 30%. Spectral studies of P450 suggested that thawing the liver samples and holding them at 25 degrees C produced inactive form P420. P450 proteins were detected by immunoblot analysis with or without thawing, but catalytic activities for individual P450s were decreased drastically by thawing and holding samples for 6 hr at 25 degrees C. Only 10% of tolbutamide methyl hydroxylation activity was present, and there was no detectable ethoxyresorufin O-deethylation activity in such microsomes after thawing and holding samples for 6 hr at 25 degrees C. Genomic DNA from human livers was also found to be degraded after the samples were thawing. These results suggested that thawing and holding the liver samples at 25 degrees C decreased the levels and activities of P450s in microsomes and that there are differences in stabilities in individual forms of P450 proteins. P450 proteins determined immunochemically do not always reflect P450-catalytic functions in human liver microsomes because of difficulties in obtaining fresh liver samples.
Protein kinase C-epsilon transgenic mice: a unique model for metastatic squamous cell carcinoma. (2001)

Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) are the most common forms of human skin cancer. BCC is slow growing and mostly localized, whereas SCC metastasizes to the regional lymph nodes and subsequently to distal organs. In murine skin carcinogenesis models for SCC, the incidence of metastasis is very low. We report here that FVB/N transgenic mice, which overexpress (approximately 18-fold) epitope-tagged protein kinase C-epsilon (T7-PKCepsilon) protein in the epidermis provide a unique murine model system for highly malignant/metastatic SCC. Skin tumors were developed by the initiation-promotion protocol (initiation with 100 nmol 7,12-dimethyl-benz[a]anthracene; promotion with 5 nmol 12-O-tetradecanoylphorbol-13-acetate twice weekly). T7-PKCepsilon transgenic mice showed 92% suppression of papilloma development compared with wild-type littermates after 23 weeks of tumor promotion. However, within 15-20 weeks of 12-O-tetradecanoylphorbol-13-acetate promotion, 40% of T7-PKCepsilon mice developed at least one carcinoma compared with 7% of the wild-type mice. All carcinomas from T7-PKCepsilon mice appeared without prior papilloma formation. Interestingly, 7,12-dimethyl-benz[a]anthracene alone resulted in the development of squamous cell carcinomas in 22% of T7-PKCepsilon mice, whereas wild-type littermates developed no tumors. Histopathological analysis of tumors from multiple T7-PKCepsilon mice revealed moderately differentiated SCC invading the dermal region with neoplasia appearing to originate and invade from the hair follicle. Carcinomas of T7-PKCepsilon mice rapidly metastasized to regional lymph nodes within 3 weeks of appearance. In wild-type mice, the grade of the invading tumors, originating from interfollicular epidermis, was pathologically categorized as well-differentiated SCC and remained localized to the dermis. The T7-PKCepsilon transgenic mice may provide a rapid and unique in vivo model to investigate metastatic SCC.
Continuous Affinity Chromatography Using a Magnetically Stabilized Fluidized Bed (1985)

A new processing tool, the magnetically stabilized fluidized bed, offers opportunities for efficient fluid-solids contact.The bubbling and mixing normally seen in a fluidized bed are eliminated, and continuous countercurrent contact is possible. This technique is especially suitable for biochemical separations, where cellular debris would clog an ordinary fixed bed. Preliminary modeling and experimental work on such a system is discussed, along with details of a relatively simple experimental system.
Cu(I)‐ and proton‐binding properties of the first N‐terminal soluble domain of <i>Bacillus subtilis</i> CopA (2011)

CopA, a P-type ATPase transporter involved in copper detoxification in Bacillus subtilis, contains two soluble Atx1-like domains separated by a short linker at its N-terminus, an arrangement that occurs widely in copper transporters from both prokaryotes and eukaryotes. Both domains were previously found to bind Cu(I) with very high affinity. Above a level of 1 Cu(I) per CopAab, dimerization occurred, leading to a highly luminescent multinuclear Cu(I) species [Singleton C & Le Brun NE (2009) Dalton Trans, 688-696]. To try to understand the contributions of each domain to the complex Cu(I)-binding behaviour of this and related proteins, we purified a wild-type form of the first domain (CopAa). In isolation, the domain bound Cu(I) with very high affinity (K = ∼ 1 × 10(18) m(-1) ) and underwent Cu(I)-mediated protein association, resulting in a mixture of dimer and tetramer species. Addition of further Cu(I) up to 1 Cu(I) per CopAa monomer led to a weakly luminescent species, whereas further additions [2 Cu(I) per CopAa monomer] resulted in protein unfolding. Analysis of the MTCAAC binding motif Cys residue acid-base properties revealed pK(a) values of 5.7 and 7.3, consistent with the pH dependence of Cu(I) binding, and with the proposal that low proton affinity is associated with high Cu(I) affinity. Finally, Cu(I) exchange between CopAa and the chelator bathocuproine sulfonate revealed rapid exchange in both directions, demonstrating an interaction between the protein and the chelator that catalyses metal ion transfer. Overall, CopAa exhibits similarities to CopAab in terms of affinity and complexity of Cu(I) binding, but the details of Cu(I) binding are distinct.
Complexes with Asymmetric Tetramine Ligands. Part I. Synthesis and Characterization of Cobalt (III) Complexes (1981)

Abstract The characterization and improved syntheses of complexes of the type [Co(Mentrien)Cl2]Cl are reported. The ligands are 5R- and 5S-Metrien, 2S,9S-Me2trien, 2S,5R,9S- and 2S,5S,9S-Me3-trien, which can be represented by the general formula H2N-CHR-CH2-NH-CH2-CHR′-NH-CH2-CHR-NH2 (R and R′ = H or CH3). Proton nmr, ir and uv-visible spectra, and ORD and CD spectra were obtained for the dichloro complexes. Assignments of absolute configuration were made on the basis of the ORD and CD curves and assignments in the literature.
Surface acoustic wave vapor sensors based on resonator devices (1991)

Surface acoustic wave (SAW) devices fabricated in the resonator configuration have been used as organic vapor sensors and compared with delay line devices more commonly used. The experimentally determined mass sensitivities of 200, 300, and 400 MHz resonators and 158 MHz delay lines coated with Langmuir-Blodgett films of poly(vinyl tetradecanal) are in excellent agreement with theoretical predictions. The response of LB- and spray-coated sensors to various organic vapors were determined, and scaling laws for mass sensitivities, vapor sensitivities, and detection limits are discussed. The 200 MHz resonators provide the lowest noise levels and detection limits of all the devices examined.
Electrocatalysis of Direct Methanol Fuel Cells (2009)

This first book to focus on a comprehensive description on DMFC electrocatalysis draws a clear picture of the current status of DMFC technology, especially the advances, challenges and perspectives in the field. Leading researchers from universities, government laboratories and fuel cell industries in North America, Europe and Asia share their knowledge and information on recent advances in the fundamental theories, experimental methodologies and research achievements.
Low Cost Cosmetic Hand Prostheses (1992)

66 patients with congenital or acquired amputations of the hand have been studied after fitting partial or complete silicone hand prostheses which can be manufactured at relatively low cost. Most patients used their prostheses on social occasions only and all but four expressed satisfaction with them.
An experimental intraarticular implantation of woven carbon fiber pad into osteochondral defect of the femoral condyle in rabbit (1991)

The defects of the articular cartilage structure are not replaced unless the subchondral plate has been breached. However, following the creation of a defect in the subchondral plate, the area is filled in with a fibrous tissue which gradually transforms to hyaline cartilage. The porous nontoxic materials of both biologic and synthetic origin have reportedly been used as matrices for repairing bone and cartilage. Following implantation, carbon fibre, chemically inert and well-tolerated by the body, induces a proliferation of ordered fibrous tissue. We implanted carbon fiber pads in osteochondral defects in rabbits. Those repairs were compared to control holes with no implants. The pads appeared to induce the gross appearance of a restored joint surface, mechanically strong to loading for periods from 2 to 6 weeks. Also, carbon fiber pads promoted the healing of the osteochondral defects in the rabbit femoral condyle, supplying well-organized cartilagenous tissue over repaired subchondral bone. The use of carbon fiber pads as implant material is suggested for the restoration of articular surface in osteoarthritis and osteochondritis dissecans.
Spatial frequency, phase, and the contrast of natural images (2002)

We examined contrast sensitivity and suprathreshold apparent contrast with natural images. The spatial-frequency components within single octaves of the images were removed (notch filtered), their phases were randomized, or the polarity of the images was inverted. Of Michelson contrast, root-mean-square (RMS) contrast, and band-limited contrast, RMS contrast was the best index of detectability. Negative images had lower apparent contrast than their positives. Contrast detection thresholds showed spatial-frequency-dependent elevation following both notch filtering and phase randomization. The peak of the spatial-frequency tuning function was approximately 0.5-2 cycles per degree (c/deg). Suprathreshold contrast matching functions also showed spatial-frequency-dependent contrast loss for both notch-filtered and phase-randomized images. The peak of the spatial-frequency tuning function was approximately 1-3 c/deg. There was no detectable difference between the effects of phase randomization and notch filtering on contrast sensitivity. We argue that these observations are consistent with changes in the activity within spatial-frequency channels caused by the higher-order phase structure of natural images that is responsible for the presence of edges and specularities.
Aromatic Substitution. XVIII.<sup>1</sup> Friedel-Crafts <i>t</i>-Butylation of Benzene and Methylbenzenes with <i>t</i>-Butyl Bromide and Isobutylene (1964)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAromatic Substitution. XVIII.1 Friedel-Crafts t-Butylation of Benzene and Methylbenzenes with t-Butyl Bromide and IsobutyleneGeorge A. Olah, Sylvia H. Flood, and Maryanne E. MoffattCite this: J. Am. Chem. Soc. 1964, 86, 6, 1060–1064Publication Date (Print):March 1, 1964Publication History Published online1 May 2002Published inissue 1 March 1964https://pubs.acs.org/doi/10.1021/ja01060a018https://doi.org/10.1021/ja01060a018research-articleACS PublicationsRequest reuse permissionsArticle Views431Altmetric-Citations26LEARN 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
Interaural Coherence Preservation in Multi-Channel Wiener Filtering-Based Noise Reduction for Binaural Hearing Aids (2015)

Besides noise reduction an important objective of binaural speech enhancement algorithms is the preservation of the binaural cues of all sound sources. To this end, an extension of the binaural multi-channel Wiener filter (MWF), namely the MWF-ITF, has been proposed, which aims to preserve the Interaural Transfer Function (ITF) of the noise sources. However, the MWF-ITF is well-suited only for directional noise sources but not for, e.g., spatially isotropic noise, whose spatial characteristics cannot be properly described by the ITF but rather by the Interaural Coherence (IC). Hence, another extension of the binaural MWF, namely the MWF-IC, has been recently proposed, which aims to preserve the IC of the noise component. Since for the MWF-IC a substantial tradeoff between noise reduction and IC preservation exists, in this paper we propose a perceptually constrained version of the MWF-IC, where the amount of IC preservation is controlled based on the IC discrimination ability of the human auditory system. In addition, a theoretical analysis of the binaural cue preservation capabilities of the binaural MWF and the MWF-ITF for spatially isotropic noise fields is provided. Several simulations in diffuse noise scenarios show that the perceptually constrained MWF-IC yields a controllable preservation of the IC without significantly degrading the output SNR compared to the binaural MWF and the MWF-ITF. Furthermore, contrary to the binaural MWF and MWF-ITF, the proposed algorithm retains the spatial separation between the output speech and noise components while the binaural cues of the speech component are only slightly distorted, such that the binaural hearing advantage for speech intelligibility can still be exploited.
PML silencing inhibits cell proliferation and induces DNA damage in cultured ovarian cancer cells (2017)

The promyelocytic leukemia (<i>PML</i>) gene is a tumor suppressor gene. It was first identified in acute promyelocytic leukemia, in which it is fused to retinoic acid receptor α by the (15;17) chromosomal translocation. The function of the PML protein is frequently lost or aberrant in human solid tumors. In human ovarian carcinoma tissue, PML detected by immunohistochemistry was highly expressed. A <i>PML</i>-silencing vector, pSRG-shPml, was constructed and used to transfect human ovarian cancer cells. Cells were cultured and selected with puromycin for 10-15 days, and then the PML mRNA expression levels were detected by RT-qPCR and immunofluorescence. Proliferation and clone number of PML-depleted cells were detected using MTT assay and colony-forming assay. The protein expression associated with DNA damage and apoptosis was assessed in PML-depleted cells using western blot analysis and immunofluorescence. The results showed that PML was highly expressed in human ovarian tissue. The proliferation and colony formation of ovarian cancer cells were significantly inhibited after PML was depleted. Western blot analysis and immunofluorescence revealed that p-H2AX and cleaved caspase-3 expression significantly increased after <i>PML</i> silencing. PML was located in the nucleus, and it formed foci after X-ray irradiation. PML foci increased significantly with increasing irradiation doses.