gebhart/patrepeval huggingface dataset:
Identification of the site of sulfation of the fourth component of human complement. (1986)

The alpha-chain of the fourth component of complement (C4) contains tyrosine sulfate (Karp, D.R. (1983) J. Biol. Chem. 258, 12745-12748). Here we have determined the site and stoichiometry of sulfation of C4 secreted by the human hepatoma-derived cell line Hep G2. C4 was labeled with [35S]sulfate and isolated from culture medium by immunoprecipitation. C4 digested with trypsin and chymotrypsin and analyzed by reverse-phase high-performance liquid chromatography contained a single sulfate-labeled peptide. Digestion of C4 with trypsin alone yielded two major sulfate-labeled peptides, suggesting that there may be some sequence variability in C4 near the site of sulfation. Sequential Edman degradation of tryptic peptides labeled with [3H]tyrosine and [35S]sulfate detected tyrosine residues at positions 5, 13, 16, and 18. Chymotrypsin cleaved 5 residues off the NH2-terminal end of tryptic peptides, yielding a peptide with tyrosine at positions 8, 11, and 13. Comparison of the position of tyrosine residues with the reported sequence of C4 identified the sites of sulfation as tyrosine residues at positions 738, 741, and 743 in the alpha-chain of C4. All 3 of these tyrosine residues appeared to be sulfated. When sulfation of C4 was partially inhibited by addition of catechol to culture medium, three different forms of the peptide were resolved by high-performance liquid chromatography, consistent with peptides containing 1, 2, or 3 sulfates. Comparison of the quantities of tyrosine and tyrosine sulfate in C4 which had been labeled with [3H]tyrosine and digested with Pronase also indicated that C4 contained an average of 2-3 residues of tyrosine sulfate/molecule. These results suggest that the biologically active form of the protein is sulfated.
Acidic and basic hydrolysis of poly(N‐vinylformamide) (2002)

Abstract Poly( N ‐vinylformamide) (PNVF) was synthesized and hydrolyzed to poly(vinylamine) (PVAm) in both HCl and NaOH solutions. The hydrolysis kinetics and the equilibrium hydrolysis were examined experimentally at different temperatures, polymer concentrations, and acid‐ or base‐to‐amide molar ratios. The hydrolysis kinetics strongly depended on temperature, polymer, and HCl or NaOH concentrations, but showed little dependence on PNVF molecular weight. The acid hydrolysis of PNVF exhibited limited conversions because of the electrostatic repulsion among the cationic amine groups generated during hydrolysis and proton hydrates. In the basic hydrolysis, complete amide conversions were observed when the NaOH/amide molar ratios were greater than unity. The effects of temperature and PNVF concentration on the equilibrium amide conversion appeared to be negligible in both acidic and basic hydrolysis. The equilibrium conversions of base hydrolysis were higher than those of acidic hydrolysis under the same reaction conditions. At NaOH/amide ratios of less than unity, the equilibrium hydrolysis experiments revealed that one base molecule could induce the hydrolysis of more than one amide group. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3412–3419, 2002
Plaque Formation by and Plaque Cloning of Chlamydia trachomatis Biovar Trachoma (1998)

A new technique for the induction of plaque formation by Chlamydia trachomatis biovar trachoma applicable to the titration of infectivity and cloning of biovar trachoma was established. Three novel strains were cloned and confirmed to be free of glycogen inclusions. The lack of glycogen accumulation correlated with the absence of a 7.5-kb plasmid, which is highly conserved in other strains of C. trachomatis. Although the growth efficiency of these plasmid-free strains was slightly lower than that of plasmid-positive strains, possession of the plasmid and glycogen accumulation were not essential for the survival of C. trachomatis.
Enantiospecific Formation of Trans 1,3-Disubstituted Tetrahydro-β-carbolines by the Pictet−Spengler Reaction and Conversion of Cis Diastereomers into Their Trans Counterparts by Scission of the C-1/N-2 Bond (1997)

The factors which effect the stereoselective formation of trans-1-alkyl-2-benzyl-3-(alkoxycarbonyl)-1,2,3,4-tetrahydro-beta-carbolines and trans-3-(alkoxycarbonyl)-1-alkyl-2-(diphenylmethyl)-1,2,3,4-tetrahydro-beta-carbolines by the Pictet-Spengler cyclization were examined by heating tryptophan derivatives with aldehydes of varied steric bulk under aprotic and acidic conditions, followed by determination of the ratio of cis to trans diastereomers so formed. The presence of a benzyl group at the N(b)-nitrogen atom alters the diastereochemical outcome of this condensation to provide 100% trans stereoselectivity when the cyclization is carried out with cyclohexanecarboxaldehyde. Furthermore, when N(b)-(diphenylmethyl)tryptophan isopropyl ester was condensed with aldehydes of any size, trans diastereomers are formed with 100% stereoselectively. The trans N(b)-substituted diastereomers are thermodynamically more stable than their cis congeners as shown by equilibration experiments in TFA. Conversion of the cis diastereomers into the more stable trans diastereomers is believed to occur under acidic conditions by cleavage of the carbon (C-1)-nitrogen (N-2) bond with complete retention of configuration at the C-3 stereocenter. Evidence from deuterium exchange experiments as well as optical rotations support this model for epimerization. In addition, when cis diastereomer 66a was allowed to stir in CF(3)COOD, the trans isomer 66b was isolated in 90% yield, while treatment of cis 66a with CF(3)COOH/NaBH(4) provided a mixture of the ring cleaved [scission across C(1)-N(2) bond] product 67 and the trans isomer 66b. Treatment of 66b (control experiment) with NaBH(4)/CF(3)COOH under the same conditions returned only starting trans 66b in excellent yield. The Pictet-Spengler reaction of substrates with sufficiently large substituents, followed by treatment with acid, permits the 100% enantiospecific formation of trans-1,3-disubstituted-1,2,3,4-tetrahydro-beta-carbolines for alkaloid total synthesis.
Analysis of Skin-Graft Loss Due to Infection (2005)

This prospective study was performed to analyze the causes of infection-related skin-graft loss in a general population of plastic and reconstructive surgery patients. One hundred thirty-two patients who received either full- or split-thickness skin grafts to reconstruct soft-tissue defects were included. The tissue defects were grouped according to the cause as follows: vascular ulcers (9.2%), burns (14.5%), traumatic tissue defects (36.6%), and flap donor-site defects (39.7%). In all cases, the preoperative evaluation indicated an adequate wound-bed preparation. However, graft loss secondary to infection was recorded in 31 patients (23.5%). The microbiological cultures revealed Pseudomonas aeruginosa in 58.1% of the cases (P<0.05), followed by Staphylococcus aureus, Enterobacter, enterococci, and Acinetobacter; 58.3% of grafts in vascular ulcers, 47.4% of grafts in burns, 16.7% of grafts in traumatic-tissue defects; and 13.5% of grafts in donor-site defects were lost due to infection. Vascular ulcers and burns were more commonly associated with graft losses due to infection than other tissue defects (P<0.001). No correlation was found between the etiological cause of the defects and the microorganisms cultured. However, Pseudomonas infections were more fulminant and caused an increased reoperation rate 4.2 times (P<0.05). Full-thickness grafts were more resistant to infection than split-thickness grafts (P<0.05). Graft loss due to infection was also more common in grafts applied to the lower extremities or when performed at multiple sites. In conclusion, 23.7% of skin grafts were lost due to infection in a group of general plastic surgery patients. Infection-related graft loss was more commonly encountered in vascular ulcers and burn wounds, and the most common cause was Pseudomonas aeruginosa.
Maleate Isomerase (1969)

Maleate isomerase from Pseudomonas puorescens catalyzes the formation of fumarate from maleate at 25" and pH 8.4; no evidence was found for the reverse reaction within the limitations of the assay procedure.The presence of an exogenous mercaptan is an absolute requirement for catalysis to occur.The enzyme has a molecular weight of 74,000 and a turnover number of 1,800 moles per mole of protein per min.
Pentacyclic triazolodiazepines as PAF‐antagonists (1991)

Abstract The syntheses of two novel pentacyclic ring systems, the thieno[3,2‐ f ][1,2,4]triazolo[4,3‐ a ][1,4]diazepino‐[4,5‐ a ]benzimidazole and the indazolo[2,3‐ d ][1,2,4]triazolo[4,3‐ a ][1,4]benzodiazepine are described. Attachment of a propargyl linked quinolinone resulted in compounds 6 and 16 which showed PAF‐antagonist activity by the intravenous route of administration in guinea pigs. The more potent compound 16 also exhibited good oral activity with an ID 50 of 0.2 mg/kg in the bronchoconstriction assay.
Plant Polyphenols: Chemical Properties, Biological Activities, and Synthesis (2011)

Eating five servings of fruits and vegetables per day! This is what is highly recommended and heavily advertised nowadays to the general public to stay fit and healthy! Drinking green tea on a regular basis, eating chocolate from time to time, as well as savoring a couple of glasses of red wine per day have been claimed to increase life expectancy even further! Why? The answer is in fact still under scientific scrutiny, but a particular class of compounds naturally occurring in fruits and vegetables is considered to be crucial for the expression of such human health benefits: the polyphenols! What are these plant products really? What are their physicochemical properties? How do they express their biological activity? Are they really valuable for disease prevention? Can they be used to develop new pharmaceutical drugs? What recent progress has been made toward their preparation by organic synthesis? This Review gives answers from a chemical perspective, summarizes the state of the art, and highlights the most significant advances in the field of polyphenol research.
Multiplex Allele-Specific Fluorescent PCR for Haplotyping the IVS8 (TG)m(T)n Locus in the CFTR Gene (2008)

The assay proved to be simple, rapid, and accurate for single-test (TG)(m)(T)(n) genotyping and suited for analysis in clinical laboratories.
Coping, Social Support, and Depressive Symptoms of Older Adults with Type II Diabetes Mellitus (2000)

Abstract This study examined the effects of coping and social support on the adaptation to Type II diabetes mellitus of elderly Chinese patients. The age of the subjects (N=200) ranged from 60 to 92 years (mean = 70.96, SD=5.84). The duration of illness since its first detection ranged from half a year to 36 years (mean = 9.14, SD=6.95). Data were collected in face-to-face interviews with a structured questionnaire. The results indicated that the patients did not perceive diabetes as severely threatening to their daily activities. Compared with a normal sample of elderly people, these diabetic elderly patients did not exhibit a higher level of depressive symptoms as measured by GDS-15.Concealment of feelings was most significantly associated with depressive symptoms. General social support appeared to be more beneficial than diabetic-specific support. Support from friends played a more significant role in the adaptation to diabetes mellitus than support from family network.
Enabling Vehicular Applications using Cloud Services through Adaptive Computation Offloading (2015)

There is growing interest in embedding new class of applications in vehicles to improve the user driving experience. However, the limited computational and storage resources in vehicles brings about a challenge of running computation and data intensive tasks of such applications in the vehicle's on-board unit (OBU). Moreover, embedded applications may not be easily updated by replacing hardware as upgrades in the vehicle OBUs can only happen over each vehicular life-cycle, which is of the order of 10-15 years. The advent of connectivity of vehicles to the Internet offers the possibility of offloading computation and data intensive tasks from the OBU to remote cloud servers for efficient execution. In this paper, we propose a novel architecture for bringing cloud-computing to vehicles where applications embedded in the vehicle OBU can benefit from remote execution of tasks provided as services in the cloud. We design a framework to identify and adaptively manage offloading of computation and data intensive tasks from the vehicle OBU to the cloud during application run-time. Through experimental evaluation using a preliminary prototype implementation of two computer vision applications that use our framework, we show that our approach can provide at least 3x reduction in the end-to-end application response time.
epsilon-Aminocaproic acid does not inhibit outflow resistance washout in monkeys. (1995)

EACA at this dose does not prevent resistance washout in the cynomolgus monkey, in contrast to the rabbit. This species difference may relate to the vastly different anatomy and physiology of their outflow pathways.
Formulation and in Vitro Evaluation of Once Daily Sustained Release Formulation of Aceclofenac (2010)

Purpose: The objective of the study was to develop matrix tablets for oral controlled release of aceclofenac using ethyl cellulose, guar gum and various grades of cellulose polymers. Methods: Possible drug-excipient interaction was evaluated by high performance liquid chromatography (HPLC) and Fourier infrared spectroscopy (FTIR). The tablets prepared were assessed for their physicochemical, in vitro drug release at pH1.2, 4.5, 6.8 and 7.5 and stability characteristics. Comparison with a ‘once daily’ commercial aceclofenac product was made in the in vitro studies. Results: There was no interaction between aceclofenac and the polymers used as excipients. Furthermore, the physicochemical properties of the tablets were satisfactory. The release profile of one of the formulated aceclofenac tablets (F7), which contained hydroxypropyl methyl cellulose (HPMC K4M), was statistically similar (p < 0.05) to that of the commercial aceclofenac brand in all the dissolution media. The formulated products ware stable and showed no changes in physical appearance, drug content, or dissolution pattern after storage at 40 oC /75 %RH for 6 months.Conclusion: The results indicate that it is feasible to achieve a stable ‘once daily’ sustained release aceclofenac tablet formulation by using HPMC K4M of 4000cps viscosity grade as matrix material.Keywords: Aceclofenac, Sustained release, Matrix tablets, Cellulose polymers, Stability studies
mirror encodes a novel PBX-class homeoprotein that functions in the definition of the dorsal-ventral border in the Drosophila eye. (1997)

The Drosophila eye is composed of dorsal and ventral mirror-image fields of opposite chiral forms of ommatidia. The boundary between these fields is known as the equator. We describe a novel gene, mirror (mrr), which is expressed in the dorsal half of the eye and plays a key role in forming the equator. Ectopic equators can be generated by juxtaposing mrr expressing and nonexpressing cells, and the path of the normal equator can be altered by changing the domain of mrr expression. These observations suggest that mrr is a key component in defining the dorsal-ventral boundary of tissue polarity in the eye. In addition, loss of mrr function leads to embryonic lethality and segmental defects, and its expression pattern suggests that it may also act to define segmental borders. Mirror is a member of the class of homeoproteins defined by the human proto-oncogene PBX1. mrr is similar to the Iroquois genes ara and caup and is located adjacent to them in this recently described homeotic cluster.
Synthesis of monosulfates of unconjugated and conjugated bile acids. (1979)

The 3-, 7- and 12-monosulfates of unconjugated, and glycine- and taurine-conjugated bile acids have been prepared. Bile acid derivatives protected by appropriate groups were sulfated in the usual manner with chlorosulfonic acid in pyridine. Subsequent removal of the protecting groups provided the desired sulfates of bile acids in satisfactory yields. The nuclear magnetic resonance spectral properties of sulfated bile acids and related compounds are briefly discussed.
A Peptide Molecule Mimicking the Copper(II) Transport Site of Human Serum Albumin (1974)

Abstract Diglycyl-l-histidine is a peptide molecule designed to mimic the specific Cu(II) transport site of human albumin. The equilibria involved in the Cu(II)-diglycyl-l-histidine system have been investigated by analytical potentiometry in aqueous solution (0.15 m NaCl, 25°). The synthetic peptide molecule bound Cu(II) exclusively as a 1:1 complex in the pH range of 6.50 to 11.00. The results further showed that the complex has the same ligand atoms binding to Cu(II) as those suggested for the specific Cu(II) binding site of human albumin. The interaction of peptide with Cu(II) in the presence of albumin, studied by equilibrium dialysis at pH 7.53 and ionic strength 0.16, indicates that this tripeptide is able to compete with albumin for Cu(II). The dissociation constant of the Cu(II)-peptide complex has a value of 1.18 x 10-16 as compared with 6.61 x 10-17 for Cu(II)-albumin. The lower Cu(II) binding strength of the peptide may reflect the influence of either the COOH-terminal free carboxyl group of the peptide or the side chain residues of the Cu(II) binding site in the native protein or both. In the presence of equimolar concentrations of albumin and peptide, and approximately 20-fold excess of l-histidine, there is about 18% of Cu(II) present in the forms of Cu(II)-albumin and l-histidine-Cu(II)-albumin, 36% in the forms of Cu(II)-peptide and l-histidine-Cu(II)-peptide, and 46% as Cu(II)-l-histidine2. The biomedical implications of designing a small molecule to mimic certain functions of a biologically important macromolecule are discussed.
Neutralizing Antibodies from the Sera of Human Immunodeficiency Virus Type 1-Infected Individuals Bind to Monomeric gp120 and Oligomeric gp140 (1998)

Antibodies that neutralize primary isolates of human immunodeficiency virus type 1 (HIV-1) appear during HIV-1 infection but are difficult to elicit by immunization with current vaccine products comprised of monomeric forms of HIV-1 envelope glycoprotein gp120. The limited neutralizing antibody response generated by gp120 vaccine products could be due to the absence or inaccessibility of the relevant epitopes. To determine whether neutralizing antibodies from HIV-1-infected patients bind to epitopes accessible on monomeric gp120 and/or oligomeric gp140 (ogp140), purified total immunoglobulin from the sera of two HIV-1-infected patients as well as pooled HIV immune globulin were selectively depleted of antibodies which bound to immobilized gp120 or ogp140. After passage of each immunoglobulin preparation through the respective columns, antibody titers against gp120 and ogp140 were specifically reduced at least 128-fold. The gp120- and gp140-depleted antibody fraction from each serum displayed reduced neutralization activity against three primary and two T-cell line-adapted (TCLA) HIV-1 isolates. Significant residual neutralizing activity, however, persisted in the depleted sera, indicating additional neutralizing antibody specificities. gp120- and ogp140-specific antibodies eluted from each column neutralized both primary and TCLA viruses. These data demonstrate the presence and accessibility of epitopes on both monomeric gp120 and ogp140 that are specific for antibodies that are capable of neutralizing primary isolates of HIV-1. Thus, the difficulties associated with eliciting neutralizing antibodies by using current monomeric gp120 subunit vaccines may be related less to improper protein structure and more to ineffective immunogen formulation and/or presentation.
THE MAMMALIAN CELL-VIRUS RELATIONSHIP (1959)

Phases of attachment, reception or penetration, and eclipse of Type 1 poliovirus infecting HeLa cells in monolayer were studied. Firm attachment was not completely dependent on salt concentration, and was sensitive to temperature change. Like attachment, progressive resistance of adsorbed virus to inactivation by externally applied antibody was temperature-sensitive. Penetration was shown to be independent of physiologic integrity of cells. Virus in process of penetration was not affected by ribonuclease. Eclipse of adsorbed virus was not dependent on metabolic activity or physical integrity of HeLa cells. Debris from poliovirus-susceptible cells inactivated the virus in a manner similar to the kinetic course of virus adsorption by intact cells, and released cell-associated infective virus in similar amounts. All cells insusceptible to poliovirus infection failed to yield active debris. Virus inactivation by debris, like virus reception by intact cells, was temperature-sensitive. Debris could not inactivate virus adsorbed to cells, or alter the progressive incapacity of antibody to neutralize penetrating virus. The active debris factor was insoluble, was not associated with cell nuclei, was inactivated by fat solvents and trypsin treatment, and was destroyed by beat inactivation or sonic disruption. Anti-HeLa serum applied to cells before exposure to virus reduced the rate of virus adsorption, while antiserum treatment immediately following virus adsorption was ineffective. These findings suggested that the capacity of HeLa and other susceptible cells to adsorb, receive, and eclipse poliovirus was associated with organized cytoplasmic lipoprotein structures not possessed by insusceptible cells. The reaction of virus with receptor substance contained in debris was not readily reversed by treatment shown not to affect virus and to destroy activity of uncombined debris. Sensitivity of poliovirus adsorption by HeLa cells to change in environmental salt concentration or temperature was dependent on the method of measurement.
Improving the Thermostability and Catalytic Efficiency of Bacillus deramificans Pullulanase by Site-Directed Mutagenesis (2013)

Pullulanase (EC 3.2.1.41) is a well-known starch-debranching enzyme. Its instability and low catalytic efficiency are the major factors preventing its widespread application. To address these issues, Asp437 and Asp503 of the pullulanase from Bacillus deramificans were selected in this study as targets for site-directed mutagenesis based on a structure-guided consensus approach. Four mutants (carrying the mutations D503F, D437H, D503Y, and D437H/D503Y) were generated and characterized in detail. The results showed that the D503F, D437H, and D503Y mutants had an optimum temperature of 55°C and a pH optimum of 4.5, similar to that of the wild-type enzyme. However, the half-lives of the mutants at 60°C were twice as long as that of the wild-type enzyme. In addition, the D437H/D503Y double mutant displayed a larger shift in thermostability, with an optimal temperature of 60°C and a half-life at 60°C of more than 4.3-fold that of the wild-type enzyme. Kinetic studies showed that the Km values for the D503F, D437H, D503Y, and D437H/D503Y mutants decreased by 7.1%, 11.4%, 41.4%, and 45.7% and the Kcat/Km values increased by 10%, 20%, 140%, and 100%, respectively, compared to those of the wild-type enzyme. Mechanisms that could account for these enhancements were explored. Moreover, in conjunction with the enzyme glucoamylase, the D503Y and D437H/D503Y mutants exhibited an improved reaction rate and glucose yield during starch hydrolysis compared to those of the wild-type enzyme, confirming the enhanced properties of the mutants. The mutants generated in this study have potential applications in the starch industry.