gebhart/patrepeval huggingface dataset:
Angiotensin II stimulates NADH and NADPH oxidase activity in cultured vascular smooth muscle cells. (1994)

The signaling pathways involved in the long-term metabolic effects of angiotensin II (Ang II) in vascular smooth muscle cells are incompletely understood but include the generation of molecules likely to affect oxidase activity. We examined the ability of Ang II to stimulate superoxide anion formation and investigated the identity of the oxidases responsible for its production. Treatment of vascular smooth muscle cells with Ang II for 4 to 6 hours caused a 2.7 +/- 0.4-fold increase in intracellular superoxide anion formation as detected by lucigenin assay. This superoxide appeared to result from activation of both the NADPH and NADH oxidases. NADPH oxidase activity increased from 3.23 +/- 0.61 to 11.80 +/- 1.72 nmol O2-/min per milligram protein after 4 hours of Ang II, whereas NADH oxidase activity increased from 16.76 +/- 2.13 to 45.00 +/- 4.57 nmol O2-/min per milligram protein. The NADPH oxidase activity was stimulated by exogenous phosphatidic and arachidonic acids and was partially inhibited by the specific inhibitor diphenylene iodinium. NADH oxidase activity was increased by arachidonic and linoleic acids, was insensitive to exogenous phosphatidic acid, and was inhibited by high concentrations of quinacrine. Both of these oxidases appear to reside in the plasma membrane, on the basis of migration of the activity after cellular fractionation and their apparent insensitivity to the mitochondrial poison KCN. These observations suggest that Ang II specifically activates enzyme systems that promote superoxide generation and raise the possibility that these pathways function as second messengers for long-term responses, such as hypertrophy or hyperplasia.
The protein receptor for cholerabacteriophage ϕ 149 (1987)

Choleraphage phi 149 receptor activity was found in the outer membrane (OM) protein of Vibrio cholerae 154. Receptor protein for phage phi 149 was separated from trypsin-treated OM on a Sephadex G-100 column. Of the three peaks obtained, phage receptor activity was noted only in peak II. SDS-PAGE showed that the Mr of the protein was 35,000. The protein was heat-labile and protease-sensitive. The specificity of this protein as choleraphage phi 149 receptor was investigated by carrying out a protection experiment by anti-protein (peak II) rabbit sera.
Breaking the Gigabit-per-second barrier with 802.11AC (2011)

Summary form only given. The 802.11ac standard will push wireless LAN throughputs over the gigabit-per-second barrier in the coming years. Rather than only improving single link throughput by using more bandwidth and 256 QAM, 802.11ac also improves network throughput by adding MU MIMO capability. MU-MIMO makes it possible to achieve large throughputs cost effectively by having relatively simple client devices with just one or two antennas that can be simultaneously transmitted to by an access point that may have up to eight antennas.
Establishment and Characterization of a Steroidogenic Human Granulosa-Like Tumor Cell Line, KGN, That Expresses Functional Follicle-Stimulating Hormone Receptor (2001)

We established a steroidogenic human ovarian granulosa-like tumor cell line, designated KGN, from a patient with invasive ovarian granulosa cell carcinoma. KGN had a relatively long population doubling time of about 46.4 h and had an abnormal karyotype of 45,XX, 7q-, -22. A steroid analysis of the cultured medium by RIA performed 5 yr after the initiation of culture showed that KGN was able to secrete pregnenolone and progesterone, and both dramatically increased after stimulation with (Bu)(2)cAMP. However, little or no secretion of 17alpha-hydroxylated steroids, dehydroepiandrosterone, androstenedione, or estradiol was observed. The aromatase activity of KGN was relatively high and was further stimulated by (Bu)(2)cAMP or FSH. These findings showed a pattern similar to that of steroidogenesis in human granulosa cells, thus allowing analysis of naturally occurring steroidogenesis in human granulosa cells. Fas-mediated apoptosis of KGN was also observed, which mimicked the physiological regulation of apoptosis in normal human granulosa cells. Based on these findings, this cell line is considered to be a very useful model for understanding the regulation of steroidogenesis, cell growth, and apoptosis in human granulosa cells.
New results on the synthesis of PID controllers (2002)

This paper considers the problem of stabilizing a first-order plant with dead time using a proportional-integral-derivative (PID) controller. Using a version of the Hermite-Biehler theorem that is applicable to quasi-polynomials, the complete set of stabilizing PID parameters is determined for both open-loop stable and unstable plants. The range of admissible proportional gains is first determined in closed form. For each proportional gain in this range, the stabilizing set in the space of the integral and derivative gains is shown to be either a trapezoid, a triangle or a quadrilateral. For the case of an open-loop unstable plant, a necessary and sufficient condition on the time delay is determined for the existence of stabilizing PID controllers.
Review article: Tissue engineering of semilunar heart valves: current status and future developments. (2004)

Heart valve replacement represents the most common surgical therapy for end-stage valvular heart diseases. One major drawback that all heart valve replacements have in common is the lack of growth, repair, and remodeling capability once implanted into the body. The emerging field of tissue engineering is focusing on the in-vitro generation of functional, living semilunar heart valve replacements. This review presents a state-of-the-art overview of the physiological and biomechanical requirements of semilunar heart valves, focusing on the aortic valve. Moreover, recent heart valve tissue engineering is summarized and future options and improvements on the way towards clinical applications are discussed.
SubVirt: implementing malware with virtual machines (2006)

Attackers and defenders of computer systems both strive to gain complete control over the system. To maximize their control, both attackers and defenders have migrated to low-level, operating system code. In this paper, we assume the perspective of the attacker, who is trying to run malicious software and avoid detection. By assuming this perspective, we hope to help defenders understand and defend against the threat posed by a new class of rootkits. We evaluate a new type of malicious software that gains qualitatively more control over a system. This new type of malware, which we call a virtual-machine based rootkit (VMBR), installs a virtual-machine monitor underneath an existing operating system and hoists the original operating system into a virtual machine. Virtual-machine based rootkits are hard to detect and remove because their state cannot be accessed by software running in the target system. Further, VMBRs support general-purpose malicious services by allowing such services to run in a separate operating system that is protected from the target system. We evaluate this new threat by implementing two proof-of-concept VMBRs. We use our proof-of-concept VMBRs to subvert Windows XP and Linux target systems, and we implement four example malicious services using the VMBR platform. Last, we use what we learn from our proof-of-concept VMBRs to explore ways to defend against this new threat. We discuss possible ways to detect and prevent VMBRs, and we implement a defense strategy suitable for protecting systems against this threat
PATRAM: A Unified Word Processing System for Handwritten Characters in Indian Languages (2007)

In this paper, we describe the design and implementation of a unified word processing system to handle handwritten characters for Indian languages. It uses XML based document format to store the strokes written by the user. It provides filters to export the native document into other standards like InkML (Ink Markup Language) and LDF (Lekhak data format). It integrates shape feature based recognition engine to recognise the whole document and spell checker to correct the wrongly recognised words. It includes the support to send the document as an attachment with E-mail without the need for recognition
Coproexamination for botulinal toxin and clostridium botulinum. A new procedure for laboratory diagnosis of botulism (1977)

Stool or serum specimens or both from 318 persons pertaining to 165 botulism investigations over a three-year period were examined. Botulinal toxin was detected in stools of 19 of 56 patients and in sera of 20 of 60 patients with clinical botulism; it was not detected in specimens from 246 persons with an illness other than botulism or well contacts of patients.<i>Clostridium botulinum</i>was identified in stools of 36 of 60 clinical botulism patients and in four of 27 asymptomatic contacts of patients with botulism victims, but not in stools of 65 persons not associated with confirmed botulism. When stool and serum samples were examined, confirmatory evidence was obtained for 72.9% of the botulism cases. Detection of botulinal toxin or<i>C botulinum</i>in the stool of a person should be considered evidence supporting the clinical diagnosis of botulism. (<i>JAMA</i>238:1829-1832, 1977)
Action of Bradykinin on Intraocular Pressure and Pupillary Diameter (1974)

Small doses (0.5 × 10––8 and 1.0 × l0––8 mol) of bradykinin were administered intracamerally to rabbit eyes undergoing closed circuit perfusion with Krebs’ saline. The response consisted of intense miosis and a sharp rise of intraocular pressure accompanied by an increase in the amount of protein appearing in the effluent. There was no significant increase prostaglandin-like activity in the effluent and the response was not abolished by the addition of indomethacin (100 μ g/ml) or atropine (8 × 10––6 g/ml) to the perfusate
Alteration of epidermal growth factor receptor activity by mutation of its primary carboxyl-terminal site of tyrosine self-phosphorylation. (1988)

The epidermal growth factor (EGF) receptor, which exhibits intrinsic protein tyrosine kinase activity, undergoes a rapid, intramolecular self-phosphorylation reaction following EGF activation. The primary sites of tyrosine self-phosphorylation in vivo are located in the extreme carboxyl-terminal region of the molecule, principally Tyr-1173. To test the biological and biochemical consequences of this EGF receptor self-phosphorylation, we made the mutation Tyr----Phe-1173. Membranes containing the mutated receptor exhibited an ED50 for EGF activation of tyrosine kinase activity equivalent to control receptor at both high and low substrate levels, but exhibited reduced basal and EGF-stimulated tyrosine kinase activity at low, non-saturating substrate levels. The Tyr----Phe-1173 mutant possessed high affinity EGF binding and could still self-phosphorylate other tyrosine sites in an intramolecular fashion with a low Km for ATP (200 nM), suggesting that this alteration did not grossly change receptor structure. When EGF-dependent growth of Chinese hamster ovary cells expressing comparable levels of control or mutant EGF receptor was measured, the ability of the mutant receptor to mediate cell growth in response to EGF was reduced by approximately 50%, yet both receptors exhibited a similar affinity and ED50 for EGF. These results support the concept that this self-phosphorylation site can act as a competitive/alternate substrate for the EGF receptor, and that this region of the molecule is important in modulating its maximal biological activity.
Metformin Is an AMP Kinase–Dependent Growth Inhibitor for Breast Cancer Cells (2006)

Recent population studies provide clues that the use of metformin may be associated with reduced incidence and improved prognosis of certain cancers. This drug is widely used in the treatment of type 2 diabetes, where it is often referred to as an "insulin sensitizer" because it not only lowers blood glucose but also reduces the hyperinsulinemia associated with insulin resistance. As insulin and insulin-like growth factors stimulate proliferation of many normal and transformed cell types, agents that facilitate signaling through these receptors would be expected to enhance proliferation. We show here that metformin acts as a growth inhibitor rather than an insulin sensitizer for epithelial cells. Breast cancer cells can be protected against metformin-induced growth inhibition by small interfering RNA against AMP kinase. This shows that AMP kinase pathway activation by metformin, recently shown to be necessary for metformin inhibition of gluconeogenesis in hepatocytes, is also involved in metformin-induced growth inhibition of epithelial cells. The growth inhibition was associated with decreased mammalian target of rapamycin and S6 kinase activation and a general decrease in mRNA translation. These results provide evidence for a mechanism that may contribute to the antineoplastic effects of metformin suggested by recent population studies and justify further work to explore potential roles for activators of AMP kinase in cancer prevention and treatment.
Vessel enhancement filtering in three‐dimensional MR angiography (1995)

For a variety of reasons, small vessels have low signal intensity in magnetic resonance angiography. When the vessel signal intensity is lower than the signal intensity of background tissues, these vessels tend not to be visible on maximum-intensity-projection images. The authors developed a nonlinear second-difference spatial filtering technique that enhances the details of small vessels while suppressing both noise and uniform background tissue. Two similar nonlinear second-difference filters are presented and compared with the linear Laplacian second-difference filter. To evaluate the performance of these filters, they were applied to intracranial three-dimensional time-of-flight MR angiographic data and the results compared with the vessel enhancement obtained with a simple second-difference Laplacian filter and with magnetization transfer contrast (MTC) techniques. The comparisons demonstrated that nonlinear filtering and MTC techniques result in similar improvement in small-vessel visibility and apparent continuity. A quantitative comparison demonstrated that the improvement in the contrast-to-noise ratio is much greater with the nonlinear filters than the Laplacian filter.
Iconic Indexing by 2-D Strings (1987)

In this paper, we describe a new way of representing a symbolic picture by a two-dimensional string. A picture query can also be specified as a 2-D string. The problem of pictorial information retrieval then becomes a problem of 2-D subsequence matching. We present algorithms for encoding a symbolic picture into its 2-D string representation, reconstructing a picture from its 2-D string representation, and matching a 2-D string with another 2-D string. We also prove the necessary and sufficient conditions to characterize ambiguous pictures for reduced 2-D strings as well as normal 2-D strings. This approach thus allows an efficient and natural way to construct iconic indexes for pictures.
Generation of biologically active IL-1 beta by matrix metalloproteinases: a novel caspase-1-independent pathway of IL-1 beta processing. (1998)

Biologic activity of IL-1 beta requires processing of the inactive precursor, a function generally ascribed to IL-1 beta-converting enzyme (caspase-1). However, alternative mechanisms of IL-1 beta activation have been postulated in local inflammatory reactions. Expression of IL-1 beta and matrix metalloproteinases (MMPs) frequently occurs simultaneously at sites of inflammation. We describe here that stromelysin-1 (MMP-3), as well as the gelatinases A (MMP-2) and B (MMP-9), processes recombinant human IL-1 beta precursor (pIL-1 beta) into biologically active forms. Detection of both pIL-1 beta processing and biologic IL-1 beta activity demonstrated different processing capacities of the respective MMPs. Conversion of pIL-1 beta by stromelysin-1 required coincubation for at least 1 h, and biologic activity faded after 8 h to 24 h. Gelatinase A was less effective in processing pIL-1 beta, requiring at least 24 h of coincubation. In contrast, gelatinase B processed pIL-1 beta within minutes, resulting in immunoreactive products as well as biologic activity stable for 72 h. In addition, prolonged incubation of mature IL-1 beta with stromelysin-1, and to a lesser extent also with gelatinases, but not with interstitial collagenase, resulted in the degradation of mature IL-1 beta. None of the MMPs processed the second isoform of IL-1, IL-1 alpha. The present study indicates a biphasic regulation of IL-1 beta activity by MMPs: a caspase-1-independent pathway of IL-1 beta activation and inhibition of IL-1 beta activity by degrading the mature cytokine. The balance of the respective MMPs and pIL-1 beta might regulate the long term appearance of IL-1 beta activity at sites of acute or chronic inflammation.
Applying radial basis functions (1996)

Discusses the application of neural networks to general and radial basis functions and in particular to adaptive equalization and interference rejection problems. Neural-network-based algorithms strike a good balance between performance and complexity in adaptive equalization, and show promise in spread spectrum systems.
Epstein-Barr virus susceptibility of normal human B lymphocyte populations. (1984)

Human blood and tonsil B lymphocytes were fractionated on density gradients and tested for virus binding and penetration into the cells. Epstein-Barr Virus (EBV) transformation was detected by immunofluorescence staining for EBV-determined nuclear antigen (EBNA). EBV bound to and penetrated all B cell populations, but only the high density populations were transformed. Activated B lymphocytes were found in the low density fractions and these cells were resistant to EBV infection. Infected and noninfected B lymphocytes were density-analyzed during in vitro culture. A spontaneous, not virus-induced, density decrease was found to precede the production of EBNA. Cells remaining at high density never expressed EBNA. The results suggest that EBV can transform only small resting B lymphocytes and that a virus-independent activation of the infected cells induces the EBNA production and transformation.
Efficient Repression of Endogenous Major Histocompatibility Complex Class II Expression through Dominant Negative CIITA Mutants Isolated by a Functional Selection Strategy (1997)

Major histocompatibility complex class II (MHC-II) molecules present peptide antigens to CD4-positive T cells and are of critical importance for the immune response. The MHC-II transactivator CIITA is essential for all aspects of MHC-II gene expression examined so far and thus constitutes a master regulator of MHC-II expression. In this study, we generated and analyzed mutant CIITA molecules which are able to suppress endogenous MHC-II expression in a dominant negative manner for both constitutive and inducible MHC-II expression. Dominant negative CIITA mutants were generated via specific restriction sites and by functional selection from a library of random N-terminal CIITA deletions. This functional selection strategy was very effective, leading to strong dominant negative CIITA mutants in which the N-terminal acidic and proline/serine/threonine-rich regions were completely deleted. Dominant negative activity is dependent on an intact C terminus. Efficient repression of endogenous MHC-II mRNA levels was quantified by RNase protection analysis. The quantitative effects of various dominant negative CIITA mutants on mRNA expression levels of the different MHC-II isotypes are very similar. The optimized dominant negative CIITA mutants isolated by functional selection should be useful for in vivo repression of MHC-II expression.
Continuous quantum error correction by cooling (2005)

We describe an implementation of quantum error correction that operates continuously in time and requires no active interventions such as measurements or gates. The mechanism for carrying away the entropy introduced by errors is a cooling procedure. We evaluate the effectiveness of the scheme by simulation, and remark on its connections to some recently proposed error prevention procedures.
Muscular Exercise, Lactic Acid, and the Supply and Utilization of Oxygen (1923)

Journal Article Muscular Exercise, Lactic Acid, and the Supply and Utilization of Oxygen Get access A. V. Hill, A. V. Hill Physiological Laboratory, Manchester Search for other works by this author on: Oxford Academic PubMed Google Scholar Hartley Lupton Hartley Lupton Physiological Laboratory, Manchester Search for other works by this author on: Oxford Academic PubMed Google Scholar QJM: An International Journal of Medicine, Volume os-16, Issue 62, January 1923, Pages 135–171, https://doi.org/10.1093/qjmed/os-16.62.135 Published: 01 January 1923
Allelic dilution obscures detection of a biologically significant resistance mutation in EGFR-amplified lung cancer (2006)

EGFR is frequently mutated and amplified in lung adenocarcinomas sensitive to EGFR inhibitors gefitinib and erlotinib. A secondary mutation, T790M, has been associated with acquired resistance but has not been shown to be sufficient to render EGFR mutant/amplified lung cancers resistant to EGFR inhibitors. We created a model for studying acquired resistance to gefitinib by prolonged exposure of a gefitinib-sensitive lung carcinoma cell line (H3255; EGFR mutated and amplified) to gefitinib in vitro. The resulting resistant cell line acquired a T790M mutation in a small fraction of the amplified alleles that was undetected by direct sequencing and identified only by a highly sensitive HPLC-based technique. In gefitinib-sensitive lung cancer cells with EGFR mutations and amplifications, exogenous introduction of EGFR T790M effectively conferred resistance to gefitinib and continued ErbB-3/PI3K/Akt signaling when in cis to an activating mutation. Moreover, continued activation of PI3K signaling by the PIK3CA oncogenic mutant, p110alpha E545K, was sufficient to abrogate gefitinib-induced apoptosis. These findings suggest that allelic dilution of biologically significant resistance mutations may go undetected by direct sequencing in cancers with amplified oncogenes and that restoration of PI3K activation via either a T790M mutation or other mechanisms can provide resistance to gefitinib.
Enantioselective 1,3‐Dipolar Cycloaddition of Nitrones with Ethyl Vinyl Ether: The Difference between Brønsted and Lewis Acid Catalysis (2008)

Brønsted and Lewis face off: A new chiral N-triflyl phosphoramide is used for asymmetric 1,3-dipolar cycloaddition of diaryl nitrones to ethyl vinyl ether to give the endo products in up to 93 % ee (see scheme; Tf=trifluoromethanesulfonyl; Ad=adamantyl). The structure of the chiral phosphoramide was confirmed by X-ray crystallographic analysis. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2008/z705314_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Circulating Angiogenic Factors and the Risk of Preeclampsia (2004)

Increased levels of sFlt-1 and reduced levels of PlGF predict the subsequent development of preeclampsia.