gebhart/patrepeval huggingface dataset:
Wideband CDMA packet data with hybrid ARQ (2002)

The performance of wideband CDMA packet data with soft combining of packets is analysed. First, the main parameters of W-CDMA (wideband CDMA) are presented. W-CDMA refers to the air interface that was decided by the ETSI to be standardised for the UMTS air interface for paired bands. Secondly, the W-CDMA packet transmission scheme with soft combining of packets is introduced. Soft combining indicates the combining of the soft values of the unsuccessful transmission with the retransmission before feeding them to the channel decoder. The performance of soft combining is compared to the performance of noncombining packet solution. The results show that soft combining can increase the capacity and extend the cell range up to 2 dB against Gaussian noise if no fast power control is used. With fast power control the gain is 0.3-2.0 dB. Soft combining can also be used to decrease the maximum packet delays. It is also shown that using slow power control instead of fast power control can increase the packet data capacity in the downlink.
MYELINATION IN RAT BRAIN: METHOD OF MYELIN ISOLATION1 (1973)

Abstract— A procedure is described for the preparation from rat brain of myelin having the same degree of purity at all ages. Such a procedure is essential for the study of myelin composition during development. Microsomal contamination was successfully eliminated by adjusting the method to maintain a constant amount of brain per unit volume in the initial density gradient step, and by including two osmotic shocks and two low‐speed centrifugation steps. Myelin prepared in this way from animals ranging from 15 days to 14months of age had a total ATPase activity of 0.3‐2.0 μmol of P i .h −1 .mg −1 dry wt of myelin, representing 0.1‐1.2 per cent recovery of the total homogenate activity; a Na + , K + ‐ ATPase activity of 0.1‐1.6 μfnol of P i .h −1 .mg −1 dry wt, representing 0.04‐1.5 per cent recovery; a nucleic acid content of 0.2‐0.7 per cent of myelin dry wt, representing 0.2‐2.0 per cent recovery; and a ganglioside NANA content of 0.04‐0.07 per cent of myelin dry wt. representing 0.2‐4.6 per cent recovery. The myelin prepared from 20‐day animals had the highest content of the first three constituents; otherwise the values of the four constituents were relatively constant per unit weight of myelin. The amounts of nucleic acid and ganglioside recovered in the myelin fractions increased with increasing age and myelin yield.
Overproduction of Aromatic Amino Acids from Cyanobacteria (2018)

L-phenylalanine, L-tyrosine and L-tryptophan are aromatic amino acids that are widely used in industrial, agricultural and pharmaceutical applications. Currently, heterotrophic microorganisms are fed require an organic source of carbon to produce amino acids, photosynthetic bacteria are investigated. Mutagenesis by methyl methanesulfonate followed by selection on aromatic amino acid analogues produced mutants that are able to overproduce aromatic amino acids. Two mutant strains were investigated: TA1, which is a better L-phenylalanine overproducer, and 5FT1, which overproduces L-tryptophan. To test the influence of growth conditions on amino acid production, we grew mutant strains of Synechocytis sp. 6803 under enhanced CO2 or glucose-rich conditions. We quantified the amount of each aromatic amino acid synthesized intracellularly and transported to extracellular medium by high performance liquid chromatography. We analysed the transient production of the aromatic amino acids to see if it is a growth related process. If it is growth related, the recommended growth method would be a fed batch reactor or a turbidostat to keep the cells at the exponential phase. If it is not growth related, we would recommend to use a batch reactor to allow cells reach stationary phase and harvest after maximum production.
Production of alcohol fuels via acid-hydrolysis extrusion technology (1981)

Pilot plant data obtained using a modified single screw grain extruder to facilitate the conversion of raw cellulosic materials into fermentable monosaccharides via acid hydrolysis are analyzed. The following are discussed: cellulose availability and cost, cellulose conversion theory, cellulose conversion performance of extrusion technology, system analysis, and economics. (MHR)
Critical Assessment of Nucleic Acid Electrostatics via Experimental and Computational Investigation of an Unfolded State Ensemble (2008)

Electrostatic forces, acting between helices and modulated by the presence of the ion atmosphere, are key determinants in the energetic balance that governs RNA folding. Previous studies have employed Poisson-Boltzmann (PB) theory to compute the energetic contribution of these forces in RNA folding. However, the complex interaction of these electrostatic forces with RNA features such as tertiary contact formation, specific ion-binding, and complex interhelical junctions present in prior studies precluded a rigorous evaluation of PB theory, especially in physiologically important Mg(2+) solutions. To critically assess PB theory, we developed a model system that isolates these electrostatic forces. The model system, composed of two DNA duplexes tethered by a polyethylene glycol junction, is an analog for the unfolded state of canonical helix-junction-helix motifs found in virtually all structured RNAs. This model system lacks the complicating features that have precluded a critical assessment of PB in prior studies, ensuring that interhelical electrostatic forces dominate the behavior of the system. The system's simplicity allows PB predictions to be directly compared with small-angle X-ray scattering experiments over a range of monovalent and divalent ion concentrations. These comparisons indicate that PB is a reasonable description of the underlying electrostatic energies for monovalent ions, but large deviations are observed for divalent ions. The validation of PB for monovalent solutions allows analysis of the change in the conformational ensemble of this simple motif as salt concentration is changed. Addition of ions allows the motif to sample more compact microstates, increasing its conformational entropy. The increase of conformational entropy presents an additional barrier to folding by stabilizing the unfolded state. Neglecting this effect will adversely impact the accuracy of folding analyses and models.
Current trends in hematopoietic stem cell transplantation in Europe (2002)

Major changes have occurred in the transplantation of hematopoietic stem cells (HSCs) during the last decade. This report reveals the changes, reflects current status, and provides medium-term projections of HSC transplantation (HSCT) development in Europe. Data on 132 963 patients, 44 165 with allogeneic HSC transplant (33%) and 88 798 with an autologous HSC transplant (67%), collected prospectively from 619 centers by the European Group for Blood and Marrow Transplantation (EBMT) in 35 European countries between 1990 (4234 HSCTs) and 2000 (19 136 HSCTs) illustrate utilization of HSCT. HSCT increased in all European countries and for all indications. There were major differences depending on disease indication and donor type. Transplantation rates (numbers of HSCTs per 10 million inhabitants) varied from less than 1 for some rare indications to 37.7 +/- 4.1 for acute myeloid leukemia in allogeneic HSCT or 95.5 +/- 13.5 for non-Hodgkin lymphoma in autologous HSCT. There were indications with a steady, continuing increase and others with initial increase but subsequent decrease. Projections on medium-term development for each disease based on a weighted sensitivity analysis predict an ongoing increase in allogeneic HSCT except for chronic myeloid leukemia. In autologous HSCT they predict an increase for lymphoproliferative disorders, acute myeloid leukemia, myelodysplastic syndromes, and some solid tumors but a decrease for most solid tumors, acute lymphoid leukemia, and chronic myeloid leukemia. Transplantation rates can be predicted with reasonable sensitivity for most disease indications. Despite marked changes in the rapidly developing field of HSCT, this information on current use, trends, and midterm predictions forms a rational basis for patient counseling and health care planning.
Binding of Specific Soluble Ribonucleic Acid to Ribosomes (1966)

Abstract The specific binding of aminoacyl soluble ribonucleic acid to 30 S ribosome subunits takes place in the presence of polyribonucleotide which contains the code for the amino acid. The binding activity of 30 S ribosome subunits was similar to that of 70 S ribosomes at 4 x 10-2 m magnesium ion concentration. Streptomycin inhibited the binding of phenylalanyl soluble ribonucleic acid to the complex of 30 S ribosome subunits and polyuridylic acid.
The Biology of Chemokines and their Receptors (2000)

During the last five years, the development of bioinformatics and EST databases has been primarily responsible for the identification of many new chemokines and chemokine receptors. The chemokine field has also received considerable attention since chemokine receptors were found to act as co-receptors for HIV infection (1). In addition, chemokines, along with adhesion molecules, are crucial during inflammatory responses for a timely recruitment of specific leukocyte subpopulations to sites of tissue damage. However, chemokines and their receptors are also important in dendritic cell maturation (2), B (3), and T (4) cell development, Th1 and Th2 responses, infections, angiogenesis, and tumor growth as well as metastasis (5). Furthermore, an increase in the number of chemokine/receptor transgenic and knock-out mice has helped to define the functions of chemokines in vivo. In this review we discuss some of the chemokines' biological effects in vivo and in vitro, described in the last few years, and the implications of these findings when considering chemokine receptors as therapeutic targets.
Impaired Myocardial Fatty Acid Oxidation and Reduced Protein Expression of Retinoid X Receptor-α in Pacing-Induced Heart Failure (2002)

Our results provide the first evidence for a link between the reduced expression of RXRalpha and the switch in metabolic phenotype in severe heart failure.
5‐HT1receptors in migraine pathophysiology and treatment (1995)

Migraine is a frequent paroxysmal headache disorder of unknown aetiology. Genetic factors may control attack frequency and possibly attack severity. Serotonin1D (5-HT1Dβ ) receptors have a prominent position within the final common pathway of the mechanisms involved in the headache and associated symptoms. Stimulation of these receptors by selective 5-HT1Dβ receptor agonists such as sumatriptan and newer compounds including MK-462 and 311C90, rapidly and fully blocks the symptoms of the headache phase. The efficacy depends on factors such as timing of administration during or before the headache, speed of initial rise of drug plasma levels, and possibly degree of brain penetration. All agonists at S-HT1Dβ receptors share a short duration of action resulting in recurrence of the headache symptoms within 24 h in about one-third of attacks in clinical trials. The risk for headache recurrence seems patient dependent: about 10% of patients treating multiple attacks experience headache recurrence in every treated attack, whereas 40% never experience recurrence. These differences are not related to simple pharmacokinetic differences between patients or drugs. Increasing plasma half-life of the drug will most likely not reduce the risk of recurrence. "Breakthrough of peripheral suppressive effect" with an ongoing "central migraine generator", rather than the occurrence of a new attack, seems to be the most likely underlying mechanism for headache recurrence. In a minority of, possibly predisposed, patients, use of sumatriptan may induce increase of attack frequency. Four mechanisms have been suggested for the antimigraine action of 5-HT1Dβ receptor agonists: (1) vasoconstriction of cranial, most likely meningeal and dural blood vessels; (2) inhibition of release of vasoactive neuropeptides from perivascular trigeminal nerve terminals within dura mater and meninges; (3) blockade of trigeminal nerve terminal depolarization; and (4) central inhibition within the trigeminal nucleus caudatus in the brainstem. Which of these mechanisms is the most important, and whether or not vasoconstrictor action is necessary for antimigraine efficacy, is currently under extensive investigation. At this point all drugs with proven antimigraine efficacy share the ability to contract blood vessels and thus all feature also the potential risk of causing vasoconstriction of coronary vessels. In relation herewith, major efforts are put into the search for "the antimigraine receptor" and which receptor subtype mediates which action of sumatriptan-like drugs. At this point, the 5-HT1Dβ receptor subtype is thought to mediate vasoconstriction. Some investigators feel that the 5-HT1Dα receptor subtype mediates the neuronal effects of sumatriptan, while others are much less convinced about the physiological role of this subtype of receptor. Further research into receptor subtype specificity and affinity of compounds may promote the development of even better antimigraine drugs.
[Protective effect of phenytoin and its enhanced action by combined administration of mannitol and vitamin E in cerebral ischemia]. (1986)

Phenytoin is well known as the anticonvulsant agent and also said to protect the brain against ischemic damage. The purpose of the present experiment is to study the therapeutic effect of phenytoin on cerebral ischemia and confirm whether the effectiveness of phenytoin could be enhanced by combination of free radical scavengers such as mannitol and vitamin E. In this experiment, twenty-five dogs were subjected to ischemia, using the "canine model of complete ischemic brain regulated with a perfusion method" in which it is possible to control the degree of blood flow to a cerebral hemisphere via a perfusion pump at will. Five animals served as untreated control, fifteen received treatment with phenytoin (7 mg/kg in five dogs, 10 mg/kg in five dogs and 30 mg/kg in five dogs) and five treated with 10 mg/kg phenytoin, 2 g/kg of mannitol and 30 mg/kg of vitamin E. These drugs were administered intravenously 20 minutes prior to the production of ischemia, when cerebral blood flow was reduced to one-tenth its normal volume. After one hour, cerebral blood flow was restored and the recovery of electrical activity of the brain and the degree of brain swelling were observed for three hours. With regard to the recovery of EEG, no recovery of EEG was seen subsequent to recirculation except one dog in the control group. Whereas in the group treated with phenytoin, gradual emergence of slow wave ws observed soon after recirculation. The higher the administered dosage is, the better the degree of recovery of EEG was seen. Thus, the dose-related recovery of EEG was observed within the dose ranges tested.(ABSTRACT TRUNCATED AT 250 WORDS)
Increased aquaporin 1 water channel expression inhuman brain tumours (2002)

Aquaporin 1 is a water channel protein. There was little aquaporin 1 immunoreactivity in normal brain parenchyma. In astrocytomas, aquaporin 1 was expressed in microvessel endothelia and neoplastic astrocytes. In metastatic carcinomas, aquaporin 1 was present in microvessel endothelia and reactive astrocytes. Aquaporin 1 may participate in the formation of brain tumour oedema.
Regulation of Annexin A2 by Reversible Glutathionylation (2004)

The annexin A2-S100A10 heterotetramer (AIIt) is a multifunctional Ca(2+)-dependent, phospholipid-binding, and F-actin-binding phosphoprotein composed of two annexin A2 subunits and two S100A10 subunits. It was reported previously that oxidative stress from exogenous hydrogen peroxide or generated in response to tumor necrosis factor-alpha results in the glutathionylation of Cys(8) of annexin A2. In this study, we demonstrate that AIIt is an oxidatively labile protein whose level of activity is regulated by the redox status of its sulfhydryl groups. Oxidation of AIIt by diamide resulted in a time- and concentration-dependent loss of the ability of AIIt to interact with phospholipid liposomes and F-actin. The inhibitory effect of diamide on the activity of AIIt was partially reversed by dithiothreitol. In addition, incubation of AIIt with diamide and GSH resulted in the glutathionylation of AIIt in vitro. Mass spectrometry established the incorporation of 2 mol of GSH/mol of annexin A2 subunit at Cys(8) and Cys(132). Glutathionylation potentiated the inhibitory effects of diamide on the activity of AIIt. Furthermore, AIIt could be deglutathionylated by glutaredoxin (thiol transferase). Thus, we show for the first time that AIIt can undergo functional reactivation by glutaredoxin, therefore establishing that AIIt is regulated by reversible glutathionylation.
Minocycline reduces gingival collagenolytic activity during diabetes (1983)

Diabetes increases gingival collagenase activity, an effect that may be mediated by endogenous tissue changes and exacerbated by an overgrowth of Gram‐negative organisms in the gingival crevice (see Ramamurthy &amp; Golub 1983, McNamara et al. 1982). In an attempt to reverse this collagenolytic abnormality, we administered an appropriate antibiotic, minocycline (a semisynthetic tetracycline), to diabetic rats and humans. Adult male conventional or germfree rats were made diabetic with streptozotocin, and half of these animals were administered minocycline (20 mg per day) by tube feeding for 3–4 weeks prior to sacrifice. The buccal gingiva, entire skins, and mandibles were dissected and tested for collagenolytic enzyme activity, collagen content, and alveolar bone loss, espectively. In a preliminary study, minocycline (200 mg per day) was administered for 7 days to an insulin‐dependent diabetic adolescent human and an adult non‐diabetic human; the twin brother of the diabetic was treated with penicillin. Gingival fluid collagenase activity was measured (using [ 3 H‐methyl] collagen as substrate in a new microassay) in 8 periodontal pockets in each subject before and after antibiotic therapy. Examination of collagenase digestion products by SDS‐polyacrylamide gel electrophoresis and fluorography was also carried out. In rats, minocycline treatment: (1) suppressed the abnormally elevated collagenolytic enzyme activity in gingiva of diabetic rats, even under germfree conditions; (2) inhibited PMN leukocyte collagenase activity in vitro , an effect that was reversed by the addition of calcium ions (penicillin‐streptomycin had no effect on the activity of this enzyme); and (3) retarded the abnormal loss of skin collagen and alveolar bone in diabetic rats. In a preliminary study on humans, minocycline therapy reduced the collagenase activity of gingival crevicular fluid, an effect not produced by penicillin. Our data suggests that (1) tetracycline therapy inhibits tissue collagenolytic enzyme activity by a mechanism al least in part unrelated to its antibacterial efficacy, and (2) this mechanism may provide a new therapeutic approach for suppressing excessive collagen resorption which occurs during periodontal disease and which can occur during other pathologic conditions.
Vehicle health monitoring for AVCS malfunction management (1993)

Vehicle health monitoring as related to malfunction management is discussed. The needs and the functions for vehicle inspection, performance monitoring and failure detection/diagnosis are addressed. The safety critical functions of an Advanced Vehicle Control System (AVCS) and the major functions using failure mode effects and critically analysis are identified. The requirements for a monitoring system regarding detection time, fail-safe characteristics and self diagnosis capability for monitoring devices are examined. Potential monitoring techniques are investigated. It is concluded that health monitoring is a vitally important function for a safety-critical system of components.
Potent Gene-Specific Inhibitory Properties of Mixed-Backbone Antisense Oligonucleotides Comprised of 2‘-Deoxy-2‘-fluoro-d-arabinose and 2‘-Deoxyribose Nucleotides, (2002)

Phosphorothioate deoxyribonucleotides (PS-DNA) are among the most widely used antisense inhibitors. PS-DNA exhibits desirable properties such as enhanced nuclease resistance, improved bioavailability, and the ability to induce RNase H mediated degradation of target RNA. Unfortunately, PS-DNA possesses a relatively low binding affinity for target RNA that impacts on its potency in antisense applications. We recently showed that phosphodiester-linked oligonucleotides comprised of 2'-deoxy-2'-fluoro-D-arabinonucleic acid (FANA) exhibit both high binding affinity for target RNA and the ability to elicit RNase H degradation of target RNA [Damha et al. (1998) J. Am. Chem. Soc. 120, 12976]. In the present study, we evaluated the antisense activity of phosphorothioate-linked FANA oligonucleotides (PS-FANA). Oligonucleotides comprised entirely of PS-FANA were somewhat less efficient in directing RNase H cleavage of target RNA as compared to their phosphorothioate-linked DNA counterparts, and showed only weak antisense inhibition of cellular target expression. However, mixed-backbone oligomers comprised of PS-FANA flanking a central core of PS-DNA were found to possess potent antisense activity, inhibiting specific cellular gene expression with EC(50) values of less than 5 nM. This inhibition was a true antisense effect, as indicated by the dose-dependent decrease in both target protein and target mRNA. Furthermore, the appearance of mRNA fragments was consistent with RNase H mediated cleavage of the mRNA target. We also compared a series of PS-[FANA-DNA-FANA] mixed-backbone oligomers of varying PS-DNA core sizes with the corresponding 2'-O-methyl oligonucleotide chimeras, i.e., PS-[2'meRNA-DNA-2'meRNA]. Both types of oligomers showed very similar binding affinities toward target RNA. However, the antisense potency of the 2'-O-methyl chimeric compounds was dramatically attenuated with decreasing DNA core size, whereas that of the 2'-fluoroarabino compounds was essentially unaffected. Indeed, a PS-FANA oligomer containing a single deoxyribonucleotide residue core retained significant antisense activity. These findings correlated exactly with the ability of the various chimeric antisense molecules to elicit RNase H degradation of the target RNA in vitro, and suggest that this mode of inhibition is likely the most important determinant for potent antisense activity.
Structure of saxitoxin in solutions and stereochemistry of dihydrosaxitoxins (1981)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure of saxitoxin in solutions and stereochemistry of dihydrosaxitoxinsYuzuru Shimizu, Chien-Ping Hsu, and Almoursi GenenahCite this: J. Am. Chem. Soc. 1981, 103, 3, 605–609Publication Date (Print):February 1, 1981Publication History Published online1 May 2002Published inissue 1 February 1981https://pubs.acs.org/doi/10.1021/ja00393a017https://doi.org/10.1021/ja00393a017research-articleACS PublicationsRequest reuse permissionsArticle Views362Altmetric-Citations48LEARN 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