gebhart/patrepeval huggingface dataset:
Synthesis and Single Molecule Force Spectroscopy of Graft Copolymers of Poly(2-hydroxyethyl methacrylate-<i>g</i>-ethylene glycol) (2004)

In this study, an end-functionalized graft copolymer, thiol-terminated poly(2-hydroxyethyl methacrylate-g-ethylene glycol) or SH-poly(HEMA-g-EG), was synthesized by the atom transfer radical polymerization (ATRP) method and then characterized by 1H nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and light scattering (LS). The polymer was covalently end-grafted to an Au substrate at low enough grafting densities to produce well-separated individual polymer “mushrooms” and single molecule force spectroscopy (SMFS) was then employed to measure the single polymer extensional elastic properties in phosphate buffered saline solution (PBS, ionic strength (IS) = 0.15 M, pH = 7.4) and deionized H2O (IS ∼ 6 × 10-5 M, pH = 5). In both solvents, the polymer behaved as an extensible freely jointed chain with a statistical segment length, a = 0.52 ± 0.09 nm, and a segment elasticity, ksegment = 10.5 ± 3.3 N/m, in PBS and a = 1.03 ± 0.01 nm and ksegment = 4.2 ± 0.5 N/m in H2O. Comparison to the known single molecule elasticity behavior for the PEG homopolymer suggests a smaller number and/or smaller magnitude of the noncovalent inter- and intramolecular interactions along the HEMA backbone and that even at this low PEG side chain grafting density, the side chains are still quite effective in causing local expansion of the PHEMA backbone by overcoming hydrophobic collapsing forces relative to the PHEMA homopolymer. Since the PEG chains are still well-solvated in PBS, one explanation for the small variation in nanomechanical properties with solvent is that in PBS the salt ions compete for and weaken the inter- and intramolecular H-bonding that does exist along the PHEMA backbone, causing a local contraction and an increased segmental stiffness due to the reduced noncovalent nature of the segments.
A mouse mammary tumor virus mammary gland enhancer confers tissue-specific but not lactation-dependent expression in transgenic mice (1992)

The long terminal repeat (LTR) of mouse mammary tumor virus (MMTV) is known to contain a number of transcriptional regulatory elements, including glucocorticoid response elements. In this study, we showed that a mammary gland/salivary gland enhancer found in the LTR of this virus directs expression of a heterologous promoter to both virgin and lactating mammary glands in transgenic mice. Using transgenic mice containing hybrid gene constructs with various deletions of the LTR sequences linked to marker genes, we also showed that the dramatic increase in MMTV expression that occurs during lactation is due to the glucocorticoid response elements. Thus, the MMTV LTR encodes two distinct elements, both of which are required for a high level of expression in lactating mammary glands.
Electrochemical Reduction of Carbon Dioxide on Stainless Steel Electrode in Acetonitrile (2013)

Electrochemical reduction of carbon dioxide (CO 2 ) to useful organic compounds is of great significance to decrease CO 2 emission. The electrochemical reduction of CO 2 is carried out in acetonitrile with tetrabutylammonium perchlorate as the electrolyte on a stainless steel cathode in a single cell; by using a sacrificial zinc anode, the product is zinc oxalate when the cathode potential is between 2.5 V and 3.5 V vs. Ag rod electrode. When the potential is less than 3.5 V, acetonitrile is decomposed, and the product is mainly zinc cyanide; when it is higher than 2.5 V, the main product is a basic zinc carbonate. Therefore, only when the cathode potential is in a proper range can CO 2 molecule obtain an electron and dimerize to form C 2 O 4 2 , which combines Zn 2+ from the anode to form zinc oxalate.
Stereospecificity of ginsenoside Rg3 in promotion of the immune response to ovalbumin in mice (2012)

Our previous investigation demonstrated that ginsenoside Rg3 was active in promotion of the immune response. In this study, two epimers, 20(R)-Rg3 and 20(S)-Rg3, were compared for their adjuvant effects on the immune response against ovalbumin (OVA). BALB/c mice were immunized subcutaneously with 10 μg of OVA alone or with 10 μg of OVA mixed in 20(R)-Rg3 (50 μg) or 20(S)-Rg3 (50 μg) on days 1 and 15. Two weeks after the last immunization, blood was sampled to test IgG and the IgG subclasses as well as IFN-γ and IL-5; splenocytes were prepared to measure proliferative responses to stimulations with Con A, LPS and OVA and mRNA expressions of cytokines and transcription factors by reverse transcription-PCR. Results indicated that both 20(R)-Rg3 and 20(S)-Rg3 exhibited the adjuvant effect on OVA-induced immune responses. 20(R)-Rg3 promoted significantly higher serum-specific IgG and the IgG isotype responses in association with highly up-regulated serum IFN-γ and IL-5 than 20(S)-Rg3. In addition, 20(R)-Rg3 significantly enhanced splenocyte proliferative responses to Con A, LPS and OVA as well as mRNA expression of IFN-γ, IL-12, IL-4 and IL-10 and transcription factors T-bet and GATA-3 by splenocytes when compared with the 20(S)-Rg3. Therefore, ginsenoside Rg3 is stereospecific in stimulation of the immune response, and 20(R)-Rg3 has more potent adjuvant activity than 20(S)-Rg3.
Low complex I content explains the low hydrogen peroxide production rate of heart mitochondria from the long‐lived pigeon,<i>Columba livia</i> (2009)

Across a range of vertebrate species, it is known that there is a negative association between maximum lifespan and mitochondrial hydrogen peroxide production. In this report, we investigate the underlying biochemical basis of the low hydrogen peroxide production rate of heart mitochondria from a long-lived species (pigeon) compared with a short-lived species with similar body mass (rat). The difference in hydrogen peroxide efflux rate was not explained by differences in either superoxide dismutase activity or hydrogen peroxide removal capacity. During succinate oxidation, the difference in hydrogen peroxide production rate between the species was localized to the DeltapH-sensitive superoxide producing site within complex I. Mitochondrial DeltapH was significantly lower in pigeon mitochondria compared with rat, but this difference in DeltapH was not great enough to explain the lower hydrogen peroxide production rate. As judged by mitochondrial flavin mononucleotide content and blue native polyacrylamide gel electrophoresis, pigeon mitochondria contained less complex I than rat mitochondria. Recalculation revealed that the rates of hydrogen peroxide production per molecule of complex I were the same in rat and pigeon. We conclude that mitochondria from the long-lived pigeon display low rates of hydrogen peroxide production because they have low levels of complex I.
Rotational adaptative-multilevel converter control strategy based on FPGA (2011)

In this paper, a control method for autonomous changing the number of parallel driven DC-DC converter is proposed. In order to improve efficiency of the parallel driving, the number of parallel driven converters is dynamically changed for the variations of output power. Taking into account the implementation requirements, the chosen platform was an Field-Programmable Gate Array (FPGA). This paper also shows in detail the analog-digital interface. The study is completed by a detailed analysis of the FPGA programming including states machines and logic diagrams. Finally, an experimental comparison with a typical single converter topology is done.
Assessment of the composition of major body regions by dual‐energy X‐ray absorptiometry (DEXA), with special reference to limb muscle mass (1992)

Dual-energy X-ray absorptiometry (DEXA) has been used to assess and compare the composition of whole body and major body regions in 12 female (weight, 56.9 +/- 6.2 kg; BMI, 17-25 kg m-2) and 16 male (weight, 73.1 +/- 9.6 kg; BMI, 20-28 kg m-2) healthy subjects. Standard deviations (and % coefficients of variation) of the differences between repeated measurements of fat ranged from 0.11 kg (9.0%) for arms to 0.42 kg (3.0%) for whole body; for arm bone mineral, 0.01 kg (2.0%), and for fat-free soft tissue of the whole body, 0.42 kg (0.8%). Limb muscle mass was estimated using a new theoretical model of body composition, and the corresponding precision ranged from 0.15 kg (3.8%) to 0.27 kg (1.5%) for arms and total limb muscle mass, respectively. Proportions of each region consisting of fat were greater in females than in males (range, 20-31% vs. 16-18%), respectively, but the ratio of trunk to leg fat was lower (34:49% vs. 46:38%, respectively). Regional proportions of bone were similar between the sexes (all in the range 2.9-5.6%, for both females and males). Mean total limb muscle masses were 14.2 kg (arms, 2.8 kg; legs, 11.4 kg) for females and 22.2 kg (arms, 4.8 kg; legs, 17.4 kg) for males, which were 33.6% and 36.0% of fat-free mass, respectively. The correlation coefficients between limb muscle (DEXA) and other indices of muscle mass were: for DEXA vs. total body potassium, 0.90 (SEE 1.1 kg muscle mass) to 0.94 (1.6 kg); and for DEXA vs. anthropometry, 0.43 (1.2 kg) to 0.85 (1.3 kg). Those for limb volume (DEXA) vs. anthropometric volume, 0.91 (0.78 1) to 0.94 (1.91 1). It is concluded that DEXA enables the valid and reproducible estimation of fat, fat-free soft tissue, bone, and limb muscle mass.
The angiogenic factor CYR61 in breast cancer: molecular pathology and therapeutic perspectives. (2003)

CYR61 (CNN1), a member of the cysteine rich 61/connective tissue growth factor/nephroblastoma overexpressed (CYR61/CTFG/NOV) family of growth regulators (CNN), is a pro-angiogenic factor that mediates diverse roles in development, cell proliferation, and tumorigenesis. We have recently shown that CYR61 is overexpressed in invasive and metastatic human breast cancer cells. Accordingly, elevated levels of CYR61 in breast cancer are associated with more advanced disease. Unfortunately, the exact mechanisms by which CYR61 promotes an aggressive breast cancer phenotype are still largely unknown. This review examines the functional role of CYR61 in breast cancer disease, presenting evidence that CYR61 signaling may play a major role in estrogen- as well as growth factor-dependent breast cancer progression. We also emphasize the functional significance of the molecular connection of CYR61 and its integrin receptor alpha(v)beta(3) enhancing breast cancer aggressiveness. Moreover, we describe experimental evidence that establishes a novel role for CYR61 determining the protection of human breast cancer cells against chemotherapy-induced apoptosis through its interactions with the integrin receptor alpha(v)beta(3). All these findings delineate a new noteworthy function of a CYR61/alpha(v)beta(3) autocrine-paracrine signaling pathway within both angiogenesis and breast cancer progression, which would allow a dual anti-angiogenic and anti-tumor benefit with a single drug.
Antimalarial drug quality: methods to detect suspect drugs (2009)

Malaria is a major public health problem in the endemic countries of Africa, Asia and Latin America. Poor quality antimalarials are of major, but neglected, concern in the control of Plasmodium falciparum malaria. They cause treatment failure and economic loss, and engender drug resistance and loss of confidence in health systems. The emergence of resistance to the artemisinin derivatives in Asia bodes ill for malaria control in Africa, and strenuous efforts are needed to improve the quality of the world's supply of antimalarials. This article reviews the problem and discusses methods available to determine the quality of antimalarials. © 2010 Future Medicine Ltd.
De novo thrombotic microangiopathy. An underrated complication of renal transplantation (2007)

After kidney transplantation thrombotic microangiopathy (TMA) may recur in patients with previous hemolytic uremic syndrome or may develop de novo. De novo TMA has been reported to occur in less than 1% of renal transplant recipients by large registries, but single center series reported an incidence of the disease as high as 14-20%. A number of factors may predispose to posttransplant TMA, including ischemia-reperfusion injury, acute rejection, viral infection. Immunosuppressive treatment can also contribute to the development of de novo TMA. Calcineurin inhibitors may cause or aggravate endothelial lesions through their pronecrotic, vasoactive and profibrotic activity. Anti-mTOR agents may delay the repair of the endothelial damage through their interference with endothelial growth factor. Usually, TMA develops in the early posttransplant period but may also occur later. Clinically, TMA is characterized by progressive renal failure and hypertension. Microangiopathic hemolytic anemia and thrombocytopenia may occur in about 60% of cases. Histologically, TMA may be localized to glomeruli or may involve arteries or both. The prognosis depends on the timely diagnosis and on histological picture. Treatment is based on the removal of inciting factors. Early plasmapheresis could improve clinical signs and symptoms and rescue renal function in a number of patients. Anecdotal successes have also been reported with intravenous immunoglobulins and rituximab.
Reconfigurable instruction set processors: a survey (2002)

Reconfigurable instruction-set processors have the capability to adapt their instruction sets to the application being executed through a reconfiguration in their hardware. Through this adaptation, they are expected to achieve a great improvement in performance compared to fixed instruction-set processors. In this paper, we discuss the different hardware aspects that have to be considered during the design of such a reconfigurable processor. The topics discussed include the coupling of the processor and the reconfigurable logic, the configuration, instruction coding and scheduling, granularity, the hardware cache and reconfigurability. A classification of current reconfigurable processors is carried out according to the discussed topics.
Chiral Acetals as Stereoinductors:  Diastereoface Selective Alkylation of Dihydrobenzoxazine-Derived Amide Enolates (2000)

Novel dihydrobenzoxazine-derived acetals of type 3 have been developed for asymmetric C-alkylations of propionyl amide enolates. High stereoselectivities are obtained for amides 15 and 22 which are rationalized in terms of intramolecular metal chelate formation.
Effect of Alkali and Enzymatic Pretreatments of <i>Eucommia ulmoides</i> Leaves and Barks on the Extraction of Gutta Percha (2008)

This paper exploited a novel method of single solvent recycling plus enzymatic pretreatment. Petroleum ether (60−90 °C) was an ideal solvent to extract Eucommia gum at high temperature (∼ 80 °C) and to precipitate the gum (flocculent) as the temperature of the solution fell to below 40 °C. The gutta percha was almost completely precipitated from solution as the temperature cooled down to below 0 °C. After filtration and recovery of the precipitated gum, the filtrate, petroleum ether, was applied to an activated carbon column to remove dissolved impurities and reused for next gutta percha extraction. Because impurities were kept in solution, the precipitated gutta percha was highly pure. In an experiment of enzyme hydrolyzing the plant cell wall, cuticle layers on the surfaces of leaves prevented cellulase from approaching to and hydrolyzing the cellulose of the cell wall. NaOH (1%) at 70 °C efficiently degraded the cuticle layer, which greatly improved the enzymatic hydrolysis of cellulose within eucommia leaves. Gutta percha that was extracted from the alkali- and cellulase-treated leaves had a degree of polymerization as high as in the leaves, and the yield increased from 2.5% of milled leaves up to over 3.2%. The tensile strength of obtained gutta percha increased from 0.02 MPa of milled Eucommia leaves to 60.5 MPa, the breakage extensibility ranged from about 0 to 24%, and the tearing strength ranged from 0.5 to 36 kN/m.
Investigation of gene and cellular therapies to cure maple syrup urine disease (MSUD) in a genetically engineered mouse model (2008)

MSUD is a serious liver-based metabolic disorder caused by a deficiency in the branched-chain alpha-ketoacid dehydrogenase (BCKDH) complex. Resulting branched-chain amino acid (BCAA) accretion in the body mainly affects the brain, which in most cases results in permanent neurological dysfunction or death without life-long attentive care. Recently it was shown liver transplantation alone restored BCKDH to a level sufficient to correct MSUD. To test novel therapies, a mouse model of intermediate MSUD (iMSUD) was created (Homanics et al., 2006), which mimicked human iMSUD. Therefore, this dissertation focused on the investigation of liver-directed therapeutic approaches to correct MSUD.In the first aim, iMSUD mice were further characterized and determined to closely mirror the human disease phenotype. iMSUD mice suffered from developmental delay, seizures, and altered brain amino acid and neurotransmitter concentration. iMSUD brains also displayed histological abnormalities while liver morphology was normal. In the second aim, adeno-associated viral (AAV) vectors were used to deliver E2 to the liver. However, no significant improvement was determined in AAV-treated iMSUD mice compared to controls. The most likely reasons this study was unsuccessful were low treatment dose, a weak albumin promoter, and possible competition and interaction between AAV-derived and iMSUD transgene-derived E2. The third aim focused on hepatocyte transplantation (HTx). iMSUD-HTx mice had a 75% reduction in BCAA/alanine levels compared to iMSUD controls. BCKDH activity was increased, and Real Time qPCR detected donor-derived E2 in the liver. Dopamine and serotonin, along with several related metabolites, were corrected to control levels. Body weight at weaning and survival were also significantly improved in iMSUD-HTx mice. The fourth aim focused on differentiated embryonic stem cell (ESC) transplantation. Differentiated ESCs expressed liver-specific markers after 3 days in culture and BCKDH activity was significantly increased over undifferentiated ESC populations. Liver-like ESC engraftment was verified up to 1 month following transplantation into wildtype mouse liver. In summary, iMSUD mice were determined to be a superior model to test novel liver-directed therapies. Our findings of partial metabolic correction of iMSUD in a mouse model by HTx were very encouraging. Therefore, liver-directed therapeutic intervention for human MSUD should be investigated further.
Advanced Thin Film Electroacoustic Devices (2007)

The explosive development of the telecom industry and in particular wireless and mobile communications in recent years has lead to a rapid development of new component and fabrication technologies to continually satisfy the mutually exclusive requirements for better performance and miniaturization on the one hand and low cost on the other. A fundamental element in radio communications is time and frequency control, which in turn is achieved by high performance electro-acoustic components made on piezoelectric single crystalline substrates. The latter, however, reach their practical limits in terms of performance and cost as the frequency of operation reaches the microwave range. Thus, the thin film electro-acoustic technology, which uses thin piezoelectric films instead, has been recently developed to alleviate these deficiencies. This thesis explores and addresses a number of issues related to thin film synthesis on the one hand as well as component design and fabrication on other. Specifically, the growth of highly c-axis textured AlN thin films has been studied and optimized for achieving high device performance. Perhaps, one of the biggest achievements of the work is the development of a unique process for the deposition of AlN films with a mean c-axis tilt, which is of vital importance for the fabrication of resonators operating in contact with liquids, i.e. biochemical sensors. This opens the way for the development of a whole range of sensors and bio-analytical tools. Further, high frequency Lamb wave resonators have been designed, fabricated and evaluated. Performance enhancement of FBAR devices is also addressed, e.g. spurious mode suppression, temperature compensation, etc. It has been demonstrated, that even without temperature compensation, shear mode resonators operating in a liquid still exhibit an excellent performance in terms of Q (200) and coupling (~1.8%) at 1.2 GHz, resulting in a mass resolution better than 2 ng cm-2 in water, which excels that of today’s quartz sensors.
Ammonia induces the mitochondrial permeability transition in primary cultures of rat astrocytes (2001)

Ammonia is a toxin that has been strongly implicated in the pathogenesis of hepatic encephalopathy (HE), and the astrocyte appears to be the principal target of ammonia toxicity. The specific neurochemical mechanisms underlying HE, however, remain elusive. One of the suggested mechanisms for ammonia toxicity is impaired cellular bioenergetics. Because there is evidence that the mitochondrial permeability transition (MPT) is associated with mitochondrial dysfunction, we determined whether the MPT might be involved in the bioenergetic alterations related to ammonia toxicity. Accordingly, we examined the mitochondrial membrane potential (Deltapsi(m)) in cultured astrocytes and neurons using laser-scanning confocal microscopy after loading the cells with the voltage-sensitive dye JC-1. We found that ammonia induced a dissipation of the Deltapsi(m) in a time- and concentration-dependent manner. These findings were supported by flow cytometry using the voltage-sensitive dye tetramethylrhodamine ethyl ester (TMRE). Cyclosporin A, a specific inhibitor of the MPT, completely blocked the ammonia-induced dissipation of the Deltapsi(m). We also found an increase in the mitochondrial permeability to 2-deoxyglucose in astrocytes that had been exposed to 5 mM NH(4)Cl, further supporting the concept that ammonia induces the MPT in these cells. Pretreatment with methionine sulfoximine, an inhibitor of glutamine synthetase, blocked the ammonia-induced collapse of Deltapsi(m), suggesting a role of glutamine in this process. Over a 24-hr period, ammonia had no effect on the Deltapsi(m) in cultured neurons. Collectively, our data indicate that ammonia induces the MPT in cultured astrocytes, which may be a factor in the mitochondrial dysfunction associated with HE and other hyperammonemic states.
Antiviral Activity of Thiazole-thiourea Derivatives (1967)

The inhibitory effect of thiazole-thiourea derivatives on poliovirus and adenovirus replication was investigated by the tissue culture method. Among the compounds tested, 1-phenyl-3-(2-thiazolyl)thiourea, (4-methyl-2-thiazolyl)thiourea, 1-p-tolyl-3-(4-methyl-2-thiazolyl) thiourea, 1-m-chlorophenyl-3-(4-methyl-2-thiazolyl)thiourea, 1-benzoyl-3-(4-methyl-2-thiazolyl)thiourea, 1-p-tolyl-3-(4-phenyl-2-thiazolyl)thiourea, and 1-p-chlorophenyl-3-(4-phenyl-2-thiazolyl)thiourea exerted a clear inhibition of the CPE and multiplication of polio virus, and 1-p-tolyl-3-(2-thiazolyl)thiourea, (4-methyl-2-thiazolyl)thiourea, 1-phenyl-3-(4-methyl-2-thiazolyl)thiourea, 1-p-chlorophenyl-3-(4-methyl-2-thiazolyl)thiourea, 1-benzoyl-3-(4-methyl-2-thiazolyl)thiourea, 1-phenyl-3-(4-phenyl-2-thiazolyl)thiourea, and 1-p-chlorophenyl-3-(4-phenyl-2-thiazolyl)thiourea showed antivira1 activity against adenovirus.