gebhart/patrepeval huggingface dataset:
Properties of a supercoiled deoxyribonucleic acid-protein relaxation complex and strand specificity of the relaxation event (1970)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTProperties of a supercoiled deoxyribonucleic acid-protein relaxation complex and strand specificity of the relaxation eventDonald R. Helinski and Don B. ClewellCite this: Biochemistry 1970, 9, 22, 4428–4440Publication Date (Print):October 1, 1970Publication History Published online1 May 2002Published inissue 1 October 1970https://pubs.acs.org/doi/10.1021/bi00824a026https://doi.org/10.1021/bi00824a026research-articleACS PublicationsRequest reuse permissionsArticle Views154Altmetric-Citations494LEARN 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
Nonexponential Nuclear Magnetic Relaxation by Quadrupole Interactions (1970)

Results are presented of calculations showing that the nuclear magnetic relaxation of the longitudinal and transverse components of a spin I are different, but each is the sum of I decaying exponential terms if I is an integer, or the sum of I + 12 decaying exponential terms if I is half an odd integer, if the relaxation is produced by quadrupole interactions for which the correlation time is not short compared to the Larmor period. Expressions for the exponents and coefficients are given in detail for the case I = 32. If the correlation time is short, the expressions reduce to the simple exponential decays calculated by previous investigators.
Proinflammatory cytokines, measured in a mixed population on arrival in the emergency department, are related to mortality and severity of disease (1997)

Carlstedt F, Lind L, Lindahl B (University Hospital of Uppsala, Sweden). Proinflammatory cytokines, measured in a mixed population on arrival in the emergency department, are related to mortality and severity of disease. J Intern Med 1997; 242 : 361–5. Objectives To investigate whether serum levels of tumour necrosis factor alpha (TNF‐α) and interleukin 6 (IL‐6) are related to mortality and severity of disease in patients admitted to the Emergency Department (ED). Design Prospective cohort study. Setting Emergency Department of a tertiary university hospital. Subjects A total of 140 patients admitted to the ED, representing common acute medical diseases, such as stroke, obstructive lung disease, heart failure, myocardial infarction, angina pectoris, infectious diseases and acute abdominal disorders. Main outcome measures APACHE II score at admission, hospital mortality and length of stay in hospital (LOS). Results A moderate rise in cytokine levels (IL‐6; 50–300 ng L −1 , TNF‐α; 10–70 ng L −1 ) was found in all diagnosis‐groups, with the most pronounced elevation seen in patients with acute abdominal disorders (up to 6900 ng L −1 ). IL‐6 on arrival to the ED was significantly correlated to the APACHE II score ( r = 0.48, P &lt; 0.0001), LOS ( r = 0.36, P &lt; 0.0001) and was elevated in nonsurvivors ( n = 9 ) compared to those who did survive. TNF‐α on arrival showed a significant correlation to LOS ( r = 0.36, P &lt; 0.0001) and APACHE II ( r = 0.41, P &lt; 0.0001), but was not associated to later mortality. Conclusions Serum levels of proinflammatory cytokines collected at admission to the ED were related to the severity of disease and hospital mortality.
Transgenic Strategy for Demonstrating Nuclear Reprogramming in the Mouse (2002)

Totipotency can be restored to the nuclei of somatic cells by reprogramming the nucleus via the technique of nuclear transfer. As genes expressed in somatic cells differ from those expressed in early embryos, a change in gene expression must accompany nuclear reprogramming. In this study, nuclear reprogramming of somatic cell nuclei following nuclear transfer (NT) was demonstrated by the reactivation of developmentally regulated lacZ reporter genes. NT embryos were generated by direct injection of adult cumulus cell nuclei into mature mouse oocytes from which maternal chromosomes were subsequently removed. Cumulus cells were collected from transgenic mice which show developmentally regulated lacZ reporter gene expression as a result of integration and functional coupling of reporter gene expression with the endogenous Oct4 or COB54 genes. As both genes are transcriptionally silent in somatic cells but are expressed during early embryonic development, reactivation of reporter gene expression in cumulus cell-derived NT embryos was assessed as a means of monitoring nuclear reprogramming. The pattern of X-gal staining observed in individual NT embryos derived from both transgenic lines revealed that coordination of reactivation appeared to be specific for each gene, and that the timing of expression was consistent with that seen in control non-manipulated transgenic embryos. However, the staining in some NT embryos appeared to be diminished or absent. This reduction in staining may indicate a failure to reprogram gene expression in these embryos. Similar transgenic strategies employing lacZ vital stains, or alter-native reporters such as GFP, may facilitate real-time monitoring of reprogramming and a potential selection strategy to increase cloning efficiency through the identification and selection of reprogrammed, preimplantation stage NT embryos prior to embryo transfer.
Tauopathy in Drosophila : Neurodegeneration Without Neurofibrillary Tangles (2001)

The microtubule-binding protein tau has been implicated in the pathogenesis of Alzheimer's disease and related disorders. However, the mechanisms underlying tau-mediated neurotoxicity remain unclear. We created a genetic model of tau-related neurodegenerative disease by expressing wild-type and mutant forms of human tau in the fruit fly Drosophila melanogaster . Transgenic flies showed key features of the human disorders: adult onset, progressive neurodegeneration, early death, enhanced toxicity of mutant tau, accumulation of abnormal tau, and relative anatomic selectivity. However, neurodegeneration occurred without the neurofibrillary tangle formation that is seen in human disease and some rodent tauopathy models. This fly model may allow a genetic analysis of the cellular mechanisms underlying tau neurotoxicity.
Differential sensitivity of human breast cancer cell lines to the growth-inhibitory effects of tamoxifen. (1985)

In eight estrogen receptor (ER)-positive breast cancer cell lines (including three sublines of MCF-7) and five ER-negative breast lines, the action of the nonsteroidal antiestrogen, tamoxifen, was studied, and the concentrations of ER and antiestrogen binding site were measured. The concentration of antiestrogen binding site was significantly [P less than 0.005] greater in ER-positive cells [236,600 +/- 29,900 (SE) sites/cell] than in ER-negative cell lines [66,600 +/- 16,800 sites/cell]. In ER-positive cell lines, a cell cycle phase-specific growth-inhibitory effect, 20% inhibitory dose less than 0.1 to 1.0 microM, was seen which was shown for some representative cell lines to be estrogen reversible. Within this group of cell lines, the degree of tamoxifen-induced inhibition of growth correlated with control population doubling time, but not ER or antiestrogen binding site concentration. The changes in cell cycle kinetic parameters characteristic of all ER-positive lines were a decrease in percentage of S-phase cells and a corresponding increase in percentage of G0-G1 cells. In all cell lines, 5 to 12.5 microM tamoxifen caused cytotoxicity, and this was shown to be estrogen-irreversible in 3 representative cell lines; moreover, estradiol synergistically enhanced the cytotoxic effects of tamoxifen under some experimental conditions. The cell cycle effects of tamoxifen in three ER-negative cell lines (Hs0578T, MDA-MB-231, MDA-MB-330) were decreased proportions of G0-G1 cells with an increase in percentages of S and G2+M cells. These results implied that the mechanism of tamoxifen cytotoxicity may differ in ER-positive and ER-negative breast cancer cells. However, although the ER-negative BT-20 line was much less sensitive to tamoxifen than were the ER-positive cells, growth inhibition and cytotoxicity in this line were associated with a slight decrease in percentage of S-phase cells. These results confirm that ER-positive breast cancer cells are more sensitive (4- to greater than 75-fold) than ER-negative breast cells to the growth-inhibitory effects of tamoxifen and demonstrate that, in all ER-positive cells, growth inhibition and cytotoxicity are accompanied by characteristic changes in cell cycle kinetic parameters. In contrast, different mechanisms may be involved in the effects of tamoxifen on different ER-negative cell lines.
Symmetry-dependent phonon renormalization in monolayer MoS2transistor (2012)

A strong electron-phonon interaction which limits the electronic mobility of semiconductors can also have significant effects on phonon frequencies. The latter is the key to the use of Raman spectroscopy for nondestructive characterization of doping in graphene-based devices. Using in situ Raman scattering from a single-layer MoS${}_{2}$ electrochemically top-gated field-effect transistor (FET), we show softening and broadening of the ${A}_{1g}$ phonon with electron doping, whereas the other Raman-active ${E}_{2g}^{1}$ mode remains essentially inert. Confirming these results with first-principles density functional theory based calculations, we use group theoretical arguments to explain why the ${A}_{1g}$ mode specifically exhibits a strong sensitivity to electron doping. Our work opens up the use of Raman spectroscopy in probing the level of doping in single-layer MoS${}_{2}$-based FETs, which have a high on-off ratio and are of technological significance.
Subnanosecond-pulse generator with variable pulsewidth using avalanche transistors (1975)

The letter describes a pulse generator with epitaxial silicon planar transistors working in the avalanche-breakdown mode. The risetime is 150 ps and the fall time 200 ps. The pulse-width can be varied continuously between 0.3 and 120 ns, without changing the maximum amplitude of about 15 V. Simple rules for the exact design of the circuitry are given.
Vitamin D3 Up-Regulated Protein 1 Mediates Oxidative Stress Via Suppressing the Thioredoxin Function (2000)

As a result of identifying the regulatory proteins of thioredoxin (TRX), a murine homologue for human vitamin D3 up-regulated protein 1 (VDUP1) was identified from a yeast two-hybrid screen. Cotransfection into 293 cells and precipitation assays confirmed that mouse VDUP1 (mVDUP1) bound to TRX, but it failed to bind to a Cys32 and Cys35 mutant TRX, suggesting the redox-active site is critical for binding. mVDUP1 was ubiquitously expressed in various tissues and located in the cytoplasm. Biochemical analysis showed that mVDUP1 inhibited the insulin-reducing activity of TRX. When cells were treated with various stress stimuli such as H2O2 and heat shock, mVDUP1 was significantly induced. TRX is known to interact with other proteins such as proliferation-associated gene and apoptosis signal-regulating kinase 1. Coexpression of mVDUP1 interfered with the interaction between TRX and proliferation-associated gene or TRX and ASK-1, suggesting its roles in cell proliferation and oxidative stress. To investigate the roles of mVDUP1 in oxidative stress, mVDUP1 was overexpressed in NIH 3T3 cells. When cells were exposed to stress, cell proliferation was declined with elevated apoptotic cell death compared with control cells. In addition, c-Jun N-terminal kinase activation and IL-6 expression were elevated. Taken together, these results demonstrate that mVDUP1 functions as an oxidative stress mediator by inhibiting TRX activity.
Review on SERS of Bacteria (2017)

Surface enhanced Raman spectroscopy (SERS) has been widely used for chemical detection. Moreover, the inherent richness of the spectral data has made SERS attractive for use in detecting biological materials, including bacteria. This review discusses methods that have been used to obtain SERS spectra of bacteria. The kinds of SERS substrates employed to obtain SERS spectra are discussed as well as how bacteria interact with silver and gold nanoparticles. The roll of capping agents on Ag/Au NPs in obtaining SERS spectra is examined as well as the interpretation of the spectral data.
A Guillotine in the Convento: Notes and Questions on Historic Ilocos Norte Churches (2000)

The historic churches of Ilocos Norte are among the province's most visited tourist spots and most recognizable symbols. One of them, Paoay, has been inscribed in the World Heritage List. Legend and oral tradition have spiced up popular perceptions of these monuments: witness the sinking bell tower of Laoag, the escape tunnel of Bacarra, the Indian or Javanese builders of Paoay, or the guillotine room of Sarrat. Some of these have been enshrined in tourist signposts. Prejudice, public credulity and lack of scientific research have added to the sensationalism. This paper does not necessarily seek to prove or disprove such oral traditions. It will, however, cite sources and perspectives not yet within the popular mind. The disappearance of an appreciation of the Spanish language will be cited as a major hindrance to the proper study of these churches. Other heretofore unrecognized church-related monuments will also be presented.
Combination of molecular rods and half-discs: transition from lamellar to columnar order in multichain mononuclearortho-palladated metallomesogens (2000)

Novel ortho-palladated phenylpyrimidine-1,3-diketonato organyls with successively increasing numbers of alkyl chains were synthesized and investigated by polarizing optical microscopy and X-ray diffraction. A discontinuous transition from a lamellar to a columnar organization is observed, dependent on the number of chains: molecules with four or five chains from smectic phases (SmA, SmC), the related compound with six chains in the molecule is nonmesomorphic, whereas molecules with seven or eight chains form hexagonal columnar mesophases.
Effect of insulin on ATP-citrate lyase phosphorylation: regulation of peptide A and peptide B phosphorylations (1989)

Insulin decreases multifunctional protein kinase (MFPK) activity in rat adipose tissue [Ramakrishna, S., & Benjamin, W. B. (1988) J. Biol. Chem. 263, 12677-12681]. Insulin also decreases the phosphorylation of peptide B but increases the phosphorylation of peptide A of ATP-citrate lyase (ATP-CL). The mechanism for this increase in peptide A phosphorylation was studied with purified ATP-CL from control and insulin- and isoproterenol-treated fat pads by using MFPK and the catalytic subunit of cAMP-dependent protein kinase (A-kinase). ATP-CL purified from insulin-treated fat pads is a better substrate for phosphorylation by MFPK compared to controls. This result is consistent with the hypothesis that insulin action decreases peptide B phosphorylation. To determine if the degree of phosphorylation at peptide B affects the phosphorylation rate of peptide A by A-kinase, ATP-CL was prepared with determined phosphate contents of peptides A and B. ATP-CL with a low phosphate content at peptide B is a better substrate for phosphorylation at peptide A by A-kinase than is ATP-CL with a high phosphate content at peptide B. These results suggest that the insulin-induced increase in ATP-CL phosphorylation at peptide A is due to a decrease in peptide B phosphorylation. ATP-CL prepared from isoproterenol-treated fat pads is also a better substrate for phosphorylation at peptide B by MFPK than controls. This increase in phosphorylation at peptide B by MFPK is due to positive second-site regulation by the isoproterenol-induced increase in peptide A phosphorylation.
Serological and Cellular Immune Activity of Peptidoglucomannan Fractions of Candida albicans Cell Walls (1974)

A two-stage extraction of isolated cell walls of C. albicans resulted in 45% solubilization into antigens of high molecular weight leaving a wall residue which also had antigenic properties. Ice-cold dilute alkali removed 25% of the defatted cell walls. The extract was nondialyzable, had a glucose-to-mannose ratio of 2:3 and an amino acid content of 7.32%, and was designated peptidoglucomannan (PGM). An additional 26% of the walls resistant to stage I were solubilized by sonic treatment yielding a fraction having a glucose-to-mannose ratio of 6:1, termed soluble mannoglucan (sMG). The residue after extraction and sonic treatment contained 10.9% mannose, which was the insoluble mannoglucan. The gel permeation behavior of PGM and sMG on BioGel A5M was similar; each contained two components, one estimated to exceed 5 x 10(6) molecular weight and a second smaller species. The soluble cell wall fractions were active in immunodiffusion and carried antigenic group specificity. Immunoelectrophoresis of PGM, sMG, and mannan revealed some heterogeneity. The insoluble mannoglucan had agglutinating activity. A distinctive immunodiffusion pattern of cell wall antigens was formed with the serum of a leukemic patient with candidiasis. All three cell wall antigens and mannan elicited delayed-type hypersensitivity as measured by skin-test and specific inhibition of macrophage migration. A dose of 25 mug of PGM was sufficient to inhibit 89.9% migration in the peritoneal exudates of guinea pigs immunized with cell walls, and 10 mug of PGM inhibited 91.7% migration in guinea pigs immunized with insoluble mannoglucan.
Preparation of Layered Double-Hydroxide Nanomaterials with a Uniform Crystallite Size Using a New Method Involving Separate Nucleation and Aging Steps (2002)

In particle formation, the method can be just as important as the chemical reaction involved. A new method of synthesizing hydrotalcite-like layered double hydroxides (LDHs) of the type [Mg1-xAlx(OH)2]x+(CO32-)x/2·yH2O (x = 1.7−3.3) is reported. The key features of this method are a very rapid mixing and nucleation process in a colloid mill followed by a separate aging process. The properties of the resulting LDHs are compared with those of materials produced using the conventional coprecipitation process at constant pH. The compositions and structural parameters of the materials synthesized using the two routes are very similar, although the crystallinity is slightly higher for the LDHs produced using the new method. The thermal behavior of the materials synthesized using the two routes is also similar. The major advantage of the new method is that it affords smaller crystallites with a higher aspect ratio, having a very narrow distribution of crystallite size. In the conventional coprecipitation process at constant pH, the mixing process takes considerable time such that nuclei formed at the beginning of the process have a much longer time to undergo crystal growth than those formed at the end of the process. The consequence is that a wide dispersion of crystallite sizes is obtained. In the colloid mill process, however, the mixing and nucleation are complete in a very short time and are followed by a separate aging process. Furthermore, we suggest that the extreme forces to which the nucleation mixture is subjected in the colloid mill prevent aggregation of the nuclei and result in the nuclei having a uniform small size. When the resulting mixture is aged in a separate process, well-formed crystallites with a similarly narrow range of diameters result.
52 mJ narrow-bandwidth degenerated optical parametric system with a large-aperture periodically poled MgO:LiNbO3 device (2006)

We have demonstrated efficient, high-energy, narrow-spectral-bandwidth 2.128 microm pulse generation by use of periodically poled MgO:LiNbO3 devices with a 36 mm length and a 5 mm x 5 mm large aperture. A free-running degenerated optical parametric oscillator (OPO) pumped with a Q-switched 1.064 microm Nd:YAG laser exhibits a high slope efficiency of 75% and an optical-to-optical conversion efficiency of 70% with a broad spectral bandwidth (>100 nm). In a configuration with a spectrally narrowed master oscillator followed by a power amplifier, we have achieved an output pulse energy of 52 mJ with a spectral bandwidth of less than 2 nm at the degeneracy point. The total optical-to-optical conversion efficiency of the system reached 50%.
In vivo measurement of the low-frequency dielectric spectra of frog skeletal muscle (1993)

Capacitance, conductance and dielectric loss spectra are obtained, in vivo, for a number of electrode separations in the gastrocnemius muscle of a frog. At each frequency the reciprocals of these parameters are plotted versus electrode separation. From the slopes of the resulting lines the complex permittivity and the conductivity of the muscle can be determined, with electrode effects eliminated. The sequence of power-law responses which is found is consistent with the fractal model proposed by Dissado. The electrical properties measured in vivo with needle electrodes are similar to those measured with surface electrodes for frequencies between 1 kHz and 1 MHz.
Effect of liposome composition and other factors on the targeting of liposomes to experimental tumors: biodistribution and imaging studies. (1990)

We have examined the distribution of radiolabeled liposomes in tumor-bearing mice after i.v. injection. Two mouse tumors (B16 melanoma, J6456 lymphoma) and a human tumor (LS174T colon carcinoma) inoculated i.m., s.c., or in the hind footpad were used in these studies. When various liposome compositions with a mean vesicle diameter of approximately 100 nm were compared using a radiolabel of gallium-67-deferoxamine, optimal tumor localization was obtained with liposomes containing a phosphatidylcholine of high phase-transition temperature and a small molar fraction of monosialoganglioside or hydrogenated phosphatidylinositol (HPI). At 24 h after injection, average values of tumor uptake higher than 10% of the injected dose per g and liver-to-tumor ratios close to 1 were reproducibly obtained. Increasing the molar fraction of HPI from 9% to 41% of the total phospholipid resulted in enhancement of liver uptake and decrease of tumor uptake. Methodological aspects that influence vesicle size appear to affect significantly liposome localization in the tumor. However, varying the phospholipid dose within a 10-fold range caused only minor changes in the percent of injected dose recovered in the tumor. A high uptake by tumors was also observed using other radiolabels [[3H]inulin and indium-111-labeled bleomycin (111In-Bleo)] in monosialoganglioside- and HPI-containing liposomes. In the case of 111In-Bleo, encapsulation in liposomes resulted in approximately 20- to 40-fold increase in tumor accumulation of the radiolabel at 24 h after injection. The marked localization of liposomes in the mouse footpad inoculated with tumor as opposed to the contralateral mock-injected footpad was also documented by imaging experiments with gallium-67-deferoxamine and 111In-Bleo-labeled liposomes. These results support the contention that some glycolipid-containing liposomes previously shown to have long circulating half-lives accumulate significantly in a variety of tumors and are promising tools for the delivery of anti-tumor agents.