Transitional cell carcinoma of urinary bladder with metastasis in lumbar vertebrae and spinal cord compression in an ocelot(Leopardus pardalis

Directory of Open Access Journals (Sweden)

Karen Y.R. Nakagaki

2015-01-01

Full Text Available This paper reports a case of nonpapillary and infiltrative transitional cell carcinoma (TCC of the urinary bladder with metastasis of lumbar vertebrae and spinal cord compression in an adult female ocelot (Leopardus pardalis, from the Mato Grosso state, Brazil. The ocelot had pelvic limb paralysis and skin ulcers in the posterior region of the body and was submitted to euthanasia procedure. At necropsy was observed a multilobulated and irregular shaped, yellowish to white nodule in the urinary bladder. The nodule had a soft consistency and arised from the mucosa of the urinary bladder extending throughout the muscular layers and the serosa. Nodules of similar appearance infiltrating the vertebral column the at L6 and L7 vertebrae with corresponding spinal canal invasion were also observed. The histological evaluation showed epithelial neoplastic proliferation in the urinary bladder with characteristics of nonpapillary and infiltrative TCC, with positive immunohistochemical staining for pancytokeratin, and strong immunostaining for cytokeratin of low molecular weight, and weak or absent labeling for high molecular weight cytokeratin. This is the first report of TCC of urinary bladder in ocelot in Brazil.

99m-Tc-aprotinin; a low molecular weight protein for the study of renal function

International Nuclear Information System (INIS)

Bianchi, C.; Donadio, C.; Tramonti, G.; Lorusso, P.; Bellitto, L.; Lunghi, F.

1982-01-01

Aprotinin (A), a low molecular weight polypeptide (6500 daltons), is a protease inhibitor which is electively accumulated in the kidney of animals. If labelled with Tcsup(99m), A is an excellent agent for renal imaging. Pharmacokinetics of A-Tcsup(99m) was studied in 53 renal patients with different degrees of renal impairment. In patients with normal or slightly impaired renal function the plasma cl of A-Tcsup(99m) was lower than the GFR (mean ratio plasma cl A-Tcsup(99m)/GFR = 0.68+-0.22 SD). In patients with renal failure, the plasma cl exceeded the GFR (mean ratio 3.35). The apparent distribution volume of A-Tcsup(99m) (percent of body weight) was 15.4+-2.5 SD. A-Tcsup(99m) was markedly and rapidly accumulated in the kidneys. In patients with unilateral kidney disease the accumulation curve of the affected kidney was flatter than that of the contralateral kidney. In 4 of these patients the functional difference between the two kidneys as given by renal accumulation of A-Tcsup(99m) (2 hrs after injection) was lower than that of GFR. Urinary excretion of radioactivity in the first 2 hrs after i.v. injection of A-Tcsup(99m) was negligible (2.4+-1.6 SD percent of the dose). Conclusions: Labelled aprotinin is promising for the study of renal handling of low molecular weight proteins and for the measurement of unilateral renal function. (Author)

Urinary concentrations of bisphenol A and phthalate metabolites and weight change: a prospective investigation in US women

Science.gov (United States)

Song, Y; Hauser, R; Hu, FB; Franke, AA; Liu, S; Sun, Q

2015-01-01

OBJECTIVE Both bisphenol A (BPA) and phthalates are known endocrine-disrupting chemicals for which there is widespread general population exposure. Human exposure occurs through dietary and non-dietary routes. Although animal studies have suggested a potential role of these chemicals in obesity, evidence from human studies is sparse and inconsistent, and prospective evidence is lacking. This study evaluated urinary concentrations of BPA and major phthalate metabolites in relation to prospective weight change. METHODS The study population was from the controls in a prospective case-control study of type 2 diabetes in the Nurses’ Health Study (NHS) and NHSII. A total of 977 participants provided first-morning-void urine samples in 1996–2002. Urinary concentrations of BPA and nine phthalate metabolites were measured using liquid chromatography–mass spectrometry. Body weights were self-reported at baseline and updated biennially thereafter for 10 years. RESULTS On average, the women gained 2.09 kg (95% confidence interval (CI), − 2.27 to 6.80 kg) during the 10-year follow-up. In multivariate analysis with adjustment of lifestyle and dietary factors, in comparison with women in the lowest quartile of BPA concentration, those in the highest quartile had 0.23 kg per year (95% CI, 0.07–0.38 kg per year) greater weight gain during the 10-year follow-up (P-trend = 0.02). Several phthalate metabolites, including phthalic acid, MBzP and monobutyl phthalate, were also associated with faster prospective weight gain in a dose-response fashion (P-trend phthalates metabolites, including MEP and monoethylhexyl phthalate, were not monotonically associated with body weight change. CONCLUSIONS These data suggest urinary concentrations of BPA and certain individual phthalate metabolites that were associated with modestly greater weight gain in a dose-response fashion. These data are consistent with a potential role of BPA and phthalates in obesity, although more prospective

Prevalence and molecular characteristics of urinary and intestinal microsporidia infections in renal transplant recipients

Czech Academy of Sciences Publication Activity Database

Kicia, M.; Wesolowska, M.; Kopacz, Z.; Jakuszko, K.; Sak, Bohumil; Květoňová, Dana; Krajewska, M.; Kváč, Martin

2016-01-01

Roč. 22, č. 5 (2016), 462.e5-462.e9 ISSN 1198-743X Institutional support: RVO:60077344 Keywords : Encephalitozoon cuniculi * Enterocytozoon bieneusi * immunosuppression * renal transplant recipients * urinary tract Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.292, year: 2016

Serum and urinary lipoproteins in the human nephrotic syndrome: evidence for renal catabolism of lipoproteins

Energy Technology Data Exchange (ETDEWEB)

Shore, V.G.; Forte, T.; Licht, H.; Lewis, S.B.

1982-03-01

The urinary excretion of lipoproteins and the possibility of catabolic alterations on glomerular filtration were investigated in four nephrotic subjects difering in etiology, serum lipoprotein profile, and 24 hr urinary output of protein and lipids. The apolipoproteins and lipoproteins of urine were compared with those of serum with respect to distribution profile, physical properties, and composition. As expected from molecular sieving effects during glomerular filtration, the urinary HDL were more abundant than the lower density lipoproteins even when the plasma LDL was elevated markedly. Intact apolipoproteins were not found in the concentrated urinary fraction isolated by ultrafiltration between the limits of 10/sup 4/ and 5 x 10/sup 4/ daltons. On the basis of immunoreactivity, gel electrophoresis, and amino acid composition, apolipoproteins B and AI are the major and minor proteins, respectively, of urinary LDL, and apo B is the major protein of the urinary IDL and VLDL. Apolipoproteins AI, AII, CI, CIII, and possibly AIV were isolated from the urinary HDL. As much as 20% of the protein moiety of the urinary HDL appeared to be large apolipoprotien fragments with molecular weights and isoelectric points similar to those of apo CII and apo CIII. The lower density classes of urinary lipoproteins also appeared to have lost apo E and apo C's and to have undergone partial proteolysis.

Effect of Sulfation and Molecular Weight on Anticoagulant Activity of Dextran.

Science.gov (United States)

Drozd, N N; Logvinova, Yu S; Torlopov, M A; Udoratina, E V

2017-02-01

Sulfation (to 2.8) of dextrans with molecular weight of 150 and 20 kDa was followed by the appearance of anticoagulant activity that increased with decreasing their molecular weight and did not depend on antithrombin, plasma inhibitor of serine proteases of the blood coagulation system. Antithrombin activity of dextran sulfate with a molecular weight of 20 kDa reached 12.6-15.3 U/mg. Dextran sulfates with molecular weights of 20 and 150 kDa did not potentiate ADP-induced human platelet aggregation.

Molecular weight (hydrodynamic volume) dictates the systemic pharmacokinetics and tumour disposition of PolyPEG star polymers.

Science.gov (United States)

Khor, Song Yang; Hu, Jinming; McLeod, Victoria M; Quinn, John F; Williamson, Mark; Porter, Christopher J H; Whittaker, Michael R; Kaminskas, Lisa M; Davis, Thomas P

2015-11-01

Herein we report for the first time the biological fate of poly[(oligoethylene glycol) acrylate] (POEGA) star polymers synthesised via a versatile arm-first reversible addition-fragmentation chain transfer (RAFT) polymerisation approach. The biopharmaceutical behaviour of three different molecular weight (49, 64 and 94kDa) POEGA stars was evaluated in rats and nude mice bearing human MDA MB-231 tumours after intravenous administration. The 94kDa star polymer exhibited a longer plasma exposure time than the 49kDa or 64kDa star polymer; an observation attributable to differences in the rates of both polymer biodegradation and urinary excretion. Tumour biodistribution also correlated with molecular weight and was greatest for the longest circulating 94kDa star. Different patterns of liver and spleen biodistribution were observed between mice and rats for the different sized polymers. The polymers were also well-tolerated in vivo and in vitro at therapeutic concentrations. Advances in nanotechnology has enabled scientists to produce nanoparticle as drug carriers in cancer therapeutics. In this article, the authors studied the biological fate of poly[(oligoethylene glycol) acrylate] (POEGA) star polymers of different size, after intravenous injections. This would allow the subsequent comparison to other drug delivery systems for better drug delivery. Copyright © 2015 Elsevier Inc. All rights reserved.

The measurement of the molecular weight of humic acid by ultracentrifugation

International Nuclear Information System (INIS)

Gardner, M.P.

1989-07-01

This report is concerned with the application of ultracentrifuge methods to the determination of humic acid molecular weights. The work has been undertaken as part of the Co-Co club intercomparison exercise on humic acid characterisation. Knowledge of the molecular weight distribution of humic acid will be an important parameter in assessing the likely physical and chemical behaviour under the near-field environment. Molecular weights of a sample of purified Aldrich humic acid have been obtained by sedimentation velocity and sedimentation equilibrium studies using an analytical ultracentrifuge. The results have shown the material to be polydisperse with a weight average molecular weight in the region 2700 to 4000. (author)

Synthesis and properties of ionic polyurethane dispersions: influence of polyol molecular weight

International Nuclear Information System (INIS)

Valipour Ebrahimi, M.; Barikani, M.; Mohammad Seyed Mohaghegh, S.

2006-01-01

A series of water dispersible polyurethanes containing carboxylate anion as the hydrophilic pendant group were prepared from toluene diisocyanate (TDI), 1,4- butanediol (1,4-BDO), dimethylol propionic acid and different molecular weight of polytetramethylene glycol . IR Spectroscopy was used to check the end of polymerization reaction and characterization of polymer. The effect of polytetramethylene glycol molecular weight was studied on the particle size distribution, contact angle, and mechanical and thermal properties of the emulsion-cast films. Average particle size of prepared polyurethane emulsions decreases with increasing the polytetramethylene glycol molecular weight. Tensile strength and hardness decrease and elongation-at-break and contact angle increase with increase of the polytetramethylene glycol molecular weight. Thermal property and thermal stability are also effected by variation of polytetramethylene glycol molecular weight. The thermal stability increases with increasing polytetramethylene glycol molecular weight. Glass transition temperature (T g ) moved toward the lower temperatures by increasing molecular weight of the polyol. Decrease in T g and tensile properties are interpreted in terms of the decrease in hard segments and the increase in chain flexibility and phase separation in high molecular weight polytetramethylene glycol based polyurethane

Anticoagulant effect of low molecular weight heparin on central ...

African Journals Online (AJOL)

Purpose: To analyse the effect of low molecular weight heparin on venous catheters in haemodialysis patients. Methods: This study included 140 eligible patients who were randomly and evenly divided into two groups, viz, a study group that received low molecular weight heparin and a control group that received ...

Virus Infection Triggers MAVS Polymers of Distinct Molecular Weight

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Natalia Zamorano Cuervo

2018-01-01

Full Text Available The mitochondrial antiviral signaling (MAVS adaptor protein is a central signaling hub required for cells to mount an antiviral response following virus sensing by retinoic acid-inducible gene I (RIG-I-like receptors. MAVS localizes in the membrane of mitochondria and peroxisomes and in mitochondrial-associated endoplasmic reticulum membranes. Structural and functional studies have revealed that MAVS activity relies on the formation of functional high molecular weight prion-like aggregates. The formation of protein aggregates typically relies on a dynamic transition between oligomerization and aggregation states. The existence of intermediate state(s of MAVS polymers, other than aggregates, has not yet been documented. Here, we used a combination of non-reducing SDS-PAGE and semi-denaturing detergent agarose gel electrophoresis (SDD-AGE to resolve whole cell extract preparations to distinguish MAVS polymerization states. While SDD-AGE analysis of whole cell extracts revealed the formation of previously described high molecular weight prion-like aggregates upon constitutively active RIG-I ectopic expression and virus infection, non-reducing SDS-PAGE allowed us to demonstrate the induction of lower molecular weight oligomers. Cleavage of MAVS using the NS3/4A protease revealed that anchoring to intracellular membranes is required for the appropriate polymerization into active high molecular weight aggregates. Altogether, our data suggest that RIG-I-dependent MAVS activation involves the coexistence of MAVS polymers with distinct molecular weights.

Preferential localization of 3H-pentosanpolysulphate to the urinary tract in rats

International Nuclear Information System (INIS)

Odlind, B.; Tengblad, A.; Dencker, L.

1987-01-01

Endogenous glycosaminoglycans probably have a protective effect in the urinary tract, e.g. against stone formation. The synthetic sulphated polysaccharide pentosanpolysulphate (PPS) has been suggested to exert a similar protective effect e.g. by inhibition of crystallization and bacterial anti-adhesion. We have studied the distribution in rats of tritium-labelled PPS. Chromatography showed this material to contain two distinct peaks with approximate molecular weight around 2.700 (60-70%) and 1.000 (30-40%) daltons. PPS was administered orally and intravenously (5 mg/kg b.wt) to Sprague-Dawley rats, which were killed 1 and 4 hours later, respectively, and subjected to whole-body autoradiography. Autoradiograms of sections from intravenously injected rats showed an extensive distribution of radioactivity in the whole animal, with a notable labelling of connective tissues, while bone and cartilage had low activity. There was upper intestine activity, suggesting some hepatic excretion. The most conspicuous finding, however, was the high concentration in urine and a preferential localization of activity corresponding to the lining of the urinary tract (pelvis, ureter, and bladder). The distribution was similar, but the activity lower after oral administration. After vigorous rinsing, with saline, the radioactivity was still retained in the bladder wall. High amount of radioactivity could be rinsed off by 0.5 M saline. Chromatography of the rinsing solution showed presence of both fractions of PPS previously found in the injection solution. No other peak of activity was found. Since PPS of molecular weight 2.700 and 1.000 is preferentially located to the surface epithelium of the urinary tract in rats, the effects of PPS in urinary tract diseases could depend on surface coating of the epithelium and/or urinary concentrations of PPS. (EG)

Development of radiation-resisting high molecular-weight materials

International Nuclear Information System (INIS)

Nakagawa, Tsutomu

1976-01-01

The excellent radiation-resisting polyvinyl chloride developed at the opportunity of the research on the relationships between the protection of living body and the polymer-technological protection from radiation is reviewed. The report is divided into four main parts, namely 1) the change in the molecular arrangement of market-available, high molecular-weight materials by gamma-ray irradiation, 2) the protection of high molecular-weight materials from radiation, 3) the relationships between the biological radiation-protective substances and the change to radiation-resisting property of synthesized high molecular-weight substances, and 4) the development of the radiation-resisting high molecular-weight materials as metal-collecting agents. Attention is paid to the polyvinyl chloride having N-methyl-dithio-carbamate radical (PMD), synthesized by the author et. al., that has excellent radiation-resisting property. PMD has some possibility to form thiol- and amino-radicals necessary to protect living things from radiation. It is believed that the protection effects of N-methyl-dithio-carbamate radical are caused by the relatively stable S radical produced by the energy transfer. PMD film is suitable for the irradiation of foods, because it hardly changes the permeability of oxygen and carbon dioxide. PMD produces mercaptide or chelate. A new metal-collecting agent (PSDC) having reactivity with the metallic ions with radiation-resisting property was developed, which is derived from polyvinyl chloride and sodium N-methyl-N-carboxy-methyl-dithio-carbamate. (Iwakiri, K.)

Molecular weight and its distribution of tetrafluoroethylene and propylene copolymer

International Nuclear Information System (INIS)

Watanabe, Hiromasa; Okamoto, Jiro; Yamaguchi, Koichi.

1978-04-01

In comparison of molecular structure of tetrafluoroethylene and propylene copolymer produced by radiation and chemical initiators respectively, both were fractionated by elution method and fine structure was examined. For the fractionated sample by radiation, the relation between molecular weight anti Mn and intrinsic viscosity ( eta] is ( eta] = 3.97 x 10 -4 anti Mnsup(0.630) The result is not in agreement with that of the unfractionated sample by radiation, and similar to those of samples by chemical initiators. There is no difference, however, in the elution method of GPC between both these copolymers; the elution behavior agrees with that of standard polystyrene. Long chain branching thus exists little in the copolymer of tetrafluoroethylene and propylene. To reveal the relations between reaction conditions and molecular weight and its distribution of the copolymer produced by flow apparatus, the molecular weight distribution was measured by GPC. The method of analysis could evaluate molecular weight distribution changing constantly. (auth.)

In vitro anticoagulation monitoring of low-molecular-weight heparin

Institute of Scientific and Technical Information of China (English)

WANG Jian-qi; SHI Xu-bo; YANG Jin-gang; HU Da-yi

2009-01-01

Background Although low-molecular-weight heparin has replaced unfractionated heparin to become the primary anticoagulation drug for treatment of acute coronary syndrome, there is no convenient bedside monitoring method. We explored the best laboratory monitoring method of low-molecular-weight heparins (enoxapadn, dalteparin, and nadroparin) by use of the Sonoclot coagulation analyzer to monitor the activated clotting time.Methods Atotal of 20 healthy volunteers were selected and 15 ml of fasting venous blood samples were collected and incubated. Four coagulants, kaolin, diatomite, glass bead, and magnetic stick, were used to determine the activated clotting time of the low-molecular-weight heparins at different in vitro anti-Xa factor concentrations. A correlation analysis was made to obtain the regression equation. The activated clotting time of the different low-molecular-weight heparins with the same anti-Xa factor concentration was monitored when the coagulant glass beads were applied. Results The activated clotting time measured using the glass beads, diatomite, kaolin, and magnetic stick showed a linear correlation with the concentration of nadroparin (r= 0.964, 0.966, 0.970, and 0.947, respectively). The regression equation showed that the linear slopes of different coagulants were significantly different (glass beads 230.03 s/IU,diatomite 89.91 s/IU, kaolin 50.87 s/IU, magnetic stick could not be calculated). When the concentration of the anti-Xa factor was the same for different low-molecular-weight heparins, the measured activated clotting time was different after the application of the glass bead coagulant.Conclusions The glass bead coagulant is most feasible for monitoring the in vitro anticoagulation activity of nadroparin.The different effects of different low-molecular-weight heparins on the activated clotting time may be related to the different anti-Ila activities.

Influence of molecular weight on the fracture properties of aliphatic polyketone terpolymers

NARCIS (Netherlands)

Zuiderduin, W.C.J.; Homminga, D.S.; Homminga, D.S.; Huetink, Han; Gaymans, R.J.

2003-01-01

The influence of polymer molecular weight on the mechanical properties of aliphatic polyketones was investigated. The molecular weight varied from 100,000 to 300,000 g mol21. The crystallinity was found to be independent of polymer molecular weight, as was the glass transition temperature. The yield

Low molecular weight heparin may benefit nephrotic remission in steroid‑sensitive nephrotic syndrome via inhibiting elastase.

Science.gov (United States)

Zhai, Songhui; Hu, Lijuan; Zhong, Lin; Tao, Yuhong; Wang, Zheng

2017-12-01

Low molecular weight heparin (LMWH) has a structure similar to heparan sulfate, which exerts anti‑inflammatory effects via inhibiting elastase (Ela) activity. Release of Ela along the glomerular capillary wall may induce glomerular injury and proteinuria. The present study aimed to investigate the influence of LMWH on steroid‑sensitive nephrotic syndrome (SSNS) and the potential underlying mechanism. A total of 40 SSNS patients and 20 healthy controls were recruited. SSNS patients were treated with LMWH and prednisone simultaneously (LMWH+pred group) or with prednisone alone (pred group). Proteinuria, urinary glycosaminoglycans (GAGs), serum Ela and urinary creatinine levels were measured. The nephrotic period of SSNS was 15.93±5.78 days. The nephrotic period of SSNS in LMWH+pred group was significantly reduced compared with the pred group (14.13±4.56 vs. 18.63±6.49 days; PEla levels (77.64±10.99 ng/l) were significantly greater in the nephrotic period of SSNS compared with the remission period (0.107±0.026 g/24 h, 1.53±0.27 mg/mmol Cr and 41.92±7.81 ng/l, respectively) and the healthy control group (0.098±0.027 g/24 h, 1.40±0.26 mg/mmol creatinine and 38.43±9.83 ng/l, respectively; PEla levels in the LMWH+pred group were significantly reduced compared with the pred group (P0.05). Positive correlations were revealed between urinary GAG excretion and proteinuria (r=0.877; PEla levels (r=0.844; PEla levels and urinary GAG excretion (r=0.881; PEla levels may induce proteinuria by degrading GAGs in the glomerular basement membrane in children with SSNS. LMWH may benefit nephrotic remission of SSNS via inhibiting Ela.

Molecular weight characterisation of synthetic polymers

CERN Document Server

Holding, Steve R

1995-01-01

The report comprises a state-of-the-art overview of the subject of molecular weight characterisation, supported by an extensive, indexed bibliography. The bibliography contains over 400 references and abstracts, compiled from the Polymer Library.

Low molecular weight salts combined with fluorinated solvents for electrolytes

Science.gov (United States)

Tikhonov, Konstantin; Yip, Ka Ki; Lin, Tzu-Yuan; Lei, Norman; Guerrero-Zavala, Guillermo; Kwong, Kristie W.

2015-11-10

Provided are electrochemical cells and electrolytes used to build such cells. An electrolyte includes at least one salt having a molecular weight less than about 250. Such salts allow forming electrolytes with higher salt concentrations and ensure high conductivity and ion transport in these electrolytes. The low molecular weight salt may have a concentration of at least about 0.5M and may be combined with one or more other salts, such as linear and cyclic imide salts and/or methide salts. The concentration of these additional salts may be less than that of the low molecular weight salt, in some embodiments, twice less. The additional salts may have a molecular weight greater than about 250. The electrolyte may also include one or more fluorinated solvents and may be capable of maintaining single phase solutions at between about -30.degree. C. to about 80.degree. C.

Western blotting of high and low molecular weight proteins using heat.

Science.gov (United States)

Kurien, Biji T; Scofield, R Hal

2015-01-01

A method for the electrophoretic transfer of high and low molecular weight proteins to nitrocellulose membranes following sodium dodecyl sulfate (SDS) polyacrylamide gel is described here. The transfer was performed with heated (70-75 °C) normal transfer buffer from which methanol had been omitted. Complete transfer of high and low molecular weight antigens (molecular weight protein standards, a purified protein, and proteins from a human tissue extract) could be carried out in 10 min for a 7 % (0.75 mm) SDS polyacrylamide gel. For 10 and 12.5 % gels (0.75 mm) the corresponding time was 15 min. A complete transfer could be carried out in 20 min for 7, 10, and 12.5 % gels (1.5 mm gels). The permeability of the gel is increased by heat, such that the proteins trapped in the polyacrylamide gel matrix can be easily transferred to the membrane. The heat mediated transfer method was compared with a conventional transfer protocol, under similar conditions. The conventional method transferred minimal low molecular weight proteins while retaining most of the high molecular weight proteins in the gel. In summary, this procedure is particularly useful for the transfer of high molecular weight proteins, very rapid, and avoids the use of methanol.

molecular weight control of a batch suspension polymerization reactor

International Nuclear Information System (INIS)

Shahrokhi, M.; Fanaei, M. A.

2002-01-01

This paper concerns molecular weight control of a batch polymerization reactor where suspension polymerization of methyl methylacrylate (MMA) takes place. For this purpose, a cascade control structure with two control loops has been selected. The slave loop is used for temperature control using on-line temperature measurements, and the master loop controls the average molecular weights based on its estimated values. Two different control algorithms namely proportional-integral (PI) controller and globally linearizing controller (GLC) have been used for temperature control. An estimator, which has the structure of an extended Kalman filter(EKF), is used for estimating monomer conversion and average molecular weights of polymer using reactor temperature measurements. The performance of proposed control algorithm is evaluated through simulation and experimental studies. The results indicate that a constant average molecular weight cannot be achieved in case of strong gel effect. However, the polydispersity of product will be lower in comparison to isothermal operation. It is also shown that in case of mo dek mismatch, the performance of cascade control is superior compared to the case where only reactor temperature is controlled based on desired temperature trajectory obtained through cascade strategy

Effect of molecular weight distribution on e-beam exposure properties of polystyrene

International Nuclear Information System (INIS)

Dey, Ripon Kumar; Cui Bo

2013-01-01

Polystyrene is a negative electron beam resist whose exposure properties can be tuned simply by using different molecular weights (Mw). Most previous studies have used monodisperse polystyrene with a polydispersity index (PDI) of less than 1.1 in order to avoid any uncertainties. Here we show that despite the fact that polystyrene’s sensitivity is inversely proportional to its Mw, no noticeable effect of very broad molecular weight distribution on sensitivity, contrast and achievable resolution is observed. It is thus unnecessary to use the costly monodisperse polystyrene for electron beam lithography. Since the polydispersity is unknown for general purpose polystyrene, we simulated a high PDI polystyrene by mixing in a 1:1 weight ratio two polystyrene samples with Mw of 170 and 900 kg mol −1 for the high Mw range, and 2.5 and 13 kg mol −1 for the low Mw range. The exposure property of the mixture resembles that of a monodisperse polystyrene with similar number averaged molecular weight (Mn)-bar, which indicates that it is (Mn)-bar rather than (Mw)-bar (weight averaged molecular weight) that dominates the exposure properties of polystyrene resist. This also implies that polystyrene of a certain molecular weight can be simulated by a mixture of two polystyrenes having different molecular weights. (paper)

[Neuroendocrine carcinoma of the urinary bladder. A case report].

Science.gov (United States)

Aragón-Tovar, Anel Rogelio; Pineda-Rodríguez, Marco Elí; Puente-Gallegos, Francisco Edgardo; Zavala-Pompa, Angel

2014-01-01

Small cell carcinoma of the urinary bladder is an infrequent lesion. We present the case of a 68-year-old male who arrived at the emergency room with a history of 24-h gross hematuria. Imaging studies show a urinary bladder tumor with a 218 cc volume that during a 20-day period increased to 426 cc. Histopathological images with hematoxylin-eosin show an infiltrating solid mass with uneven borders. It is composed of neoplastic cells with evident nuclei predominance and scant cytoplasm (small cells). Chromogranin immunohistochemical staining shows a diffusely positive cytoplasmic granular pattern on neoplastic cells. High molecular weight cytokeratin staining shows a negative pattern on neoplastic cells along with a positive pattern on reporsurrounding normal urothelium. Tumoral mass is positive for synaptophysin and CD-56 and negative for CK-7 and CK-20. Patient therapy was based on radiation plus chemotherapy. Small cell carcinoma of the urinary bladder represents 0.35-0.70% of urinary bladder tumors. Histological and immunohistochemical identification are key elements in the diagnosis. Treatment approach is based on cisplatin-based chemotherapy plus radical cystectomy, except when metastatic disease is present.

Effect of molecular weight on the quality of poly(alpha-methylstyrene mandrel

Directory of Open Access Journals (Sweden)

Xiuyun Shangguan

2017-07-01

Full Text Available Hollow poly(alpha-methylstyrene (PAMS shows application in inertial confinement fusion experiments as the degradable mandrels of glow plasma polymer shells. However, the molecular weight of PAMS has great influence on the quality of mandrels. In this work, this influence was systematically studied using several PAMS samples with different molecular weights. For PAMS shells with 900 μm inner diameter and different wall thickness, when the molecular weight of PAMS is in the range of 300–500 kg·mol−1, perfect sphericity and good wall thickness uniformity can be obtained. In contrast, when increasing molecular weight to 800 kg·mol−1, the sphericity and the wall thickness uniformity become worse. Moreover, compared with the wall uniformity, the sphericity of PAMS shells was much less sensitive to the molecular weight. The results also showed that the stability of W1/O compound droplets of PAMS shells were less affected by the molecular weight. It was revealed that the wall uniformity and the sphericity of the PAMS shells were associated with the diffusion rates of fluorobenzene (FB.

Hydrodynamic characterization and molecular weight estimation of ultrasonically sheared DNA

International Nuclear Information System (INIS)

Casal, J. I.; Garces, F.; Garcia-Sacristan, A.

1981-01-01

The sedimentation coefficients and intrinsic viscosities of ultrasonically sheared calf thymus DNA have been determined. The molecular weight estimation according to this parameters have been compared with the ones obtained from the electrophoretic migration rates based on the calibration proposed using the known molecular weight restriction fragments of X-ENA. (Author) 35 refs

Hydrodynamic caracterization and molecular weight stimation of ultrasonically sheared DNA

International Nuclear Information System (INIS)

Garces, F.; Casal, J.I.; Garcia, A.

1981-01-01

The sedimentation coefficients and intrinsec viscosities of ultrasonically sheared calf thymus DNA have been determined. The molecular weight stimation according to this parameters have been compared with the ones obtained from the electrophoretic migration rates based on the calibration proposed using the known molecular weight restriction fragments of lambds-DNA. (author) [es

Micellization of symmetric PEP-PEO block copolymers in water molecular weight dependence

CERN Document Server

Kaya, H; Allgaier, J; Stellbrink, J; Richter, D

2002-01-01

The micellar behaviour of the amphiphilic block copolymer poly-(ethylene-propylene)-poly-(ethylene oxide) (PEP-PEO) in aqueous solution has been studied with small-angle neutron scattering. The polymer was studied over a wide range of molecular weights, always keeping the volume of the blocks equal. The scattering behaviour of the solutions showed that a morphological transition takes place upon lowering the molecular weight. The high molecular weight block copolymers all build spherical, monodisperse micelles with large aggregation numbers. At low molecular weights, however, cylindrical micelles are formed. An interesting intermediate case is represented by the PEP2-PEO2 system, in which a morphological transition occurs upon dilution. (orig.)

Low molecular weight block copolymers as plasticizers for polystyrene

DEFF Research Database (Denmark)

Hansen, Kristoffer Karsten; Nielsen, Charlotte Juel; Hvilsted, Søren

2005-01-01

/mol and minimum polystyrene content of 50 w/w%, which by us is predicted as the limits for solubility of polystyrene-b-alkyl in polystyrene. DSC showed polystyrene was plasticized, as seen by a reduction in glass transition temperature, by block copolymers consisting of a polystyrene block with molecular weight...... of approximately 1 kg/mol and an alkyl block with a molecular weight of approximately of 0.3 kg/mol. The efficiency of the block copolymers as plasticizers increases with decreasing molecular weight and polystyrene content. In addition, polystyrene-b-alkyl is found to be an efficient plasticizer also...... for polystyrene-b-polyisoprene-b-polystyrene (SIS) block copolymers. The end use properties of SIS plasticized with polystyrene-b-alkyl, measured as tensile strength, is higher than for SIS plasticized with dioctyl adipate. The polystyrene-b-polybutadiene-b-polystyrene and polystyrene-bpoly(propylene glycol...

Radiation polymerization of acrylamide with super-high molecular weight in inverse emulsion

International Nuclear Information System (INIS)

Ye Qiang; Ge Xuewu; Xu Xiangling; Zhang Zhicheng

1998-01-01

The inverse emulsion polymerization of acrylamide has been studied with γ-ray initiation. Polyacrylamide with super high molecular weight over ten million (11 x 10 6 ), which is very important in application as flocculant, is obtained. In this work, some methods are taken to enhance the molecular weight as follows: (1) In order to prepare soluble polyacrylamide with super high molecular weight, the better conditions are: the emulsifier content is about 2% and the monomer concentration is about 20%∼24% in the composition of monomer emulsion, and the absorbed dose is about 500∼600 Gy. (2) Initiating with high dose rate and polymerizing with low dose rate can not only enhance the molecular weight of product, but also curtail the polymerizing time. (3) Stopping radiation when the conversion gets to about 10% and post-polymerizing outside the radiation source until the conversion gets to 82% can obtain polyacrylamide with super high molecular weight, and shorten the irradiation time as well

Influences of gamma irradiation treatment on the molecular weight of chitosan

International Nuclear Information System (INIS)

Luu Thi Tho; Nguyen Viet Thong; Tran Minh Quynh; Vu Thi Hong Khanh

2013-01-01

Effects of gamma radiation on molecular properties of shrimp and squid chitosan (MTV, Vietnam) have been studied with three kind chitosan that having degree of deacetylation 75% and different molecular molecular weight of 69, 187 and 345 kDa, Chitosan samples were irradiated at the same dose rate of 4.3 kGy per hour with various radiation dose of 25, 50, 75, 100, 200 and 500 kGy. The viscosity average molecular weight and degree of deacetylation (DD) of chitosan before and after irradiation have been investigated via their intrinsic viscosity and Furrier transform infra-red (FT-IR). The data revealed the chitosan backbone chains has been degraded by gamma radiation, resulting in the smaller fragments with reduced molecular weight to 3000 Da, whereas their DD have not much changed. (author)

The distribution of 14C-chitosan by different molecular weight in mice

International Nuclear Information System (INIS)

Kim, Kwang Yoon; Kim, Young Ho; Bom, Hee Seung; Kim, Ji Yeul; Kim, Hee Kyung; Roh, Young Bok; Nishimura, Yoshikazu

1998-01-01

Chitosan is a nontoxic natural chealtor which was made by chitin, and reduced a contamination of radiostrontium in animals. In this experiment, a different molecular weight of C-14 chitosan was intravenously administered to mice, and then the distribution of C-14 chitosan in the body was observed. Male mice (8 to 10 weeks, body weight of 30 to 35g) of ICR strain were used. C-14 chitosan, mice was sacrificed at the 6th hour, 1st, 3rd, 5th, and 7th day. Beta radioactivities in the blood, liver, kidney, liver, muscle, testis, and urine was measured using a liquid scintillation analyzer. Most of the C-14 chitosan was excreted through urine within 6 hours. Biodistribution of C-14 chitosan was similar despite the difference of molecular weight. Higher distributions of radioactivities were found in the liver, kidney, spleen. The relative concentration in tissue increased for the 6 hours and then decreased. In conclusion, most of C-14 chitosan was excreted through urine despite the difference of molecular weight. and, low molecular weight of C-14 chitosan showed higher distribution than high molecular weight of C-14 chitosan in tissues

Children with atopic dermatitis and frequent emollient use have increased urinary levels of low-molecular-weight phthalate metabolites and parabens

DEFF Research Database (Denmark)

Overgaard, L E K; Main, K M; Frederiksen, H

2017-01-01

BACKGROUND: Parabens may be added to cosmetic and personal care products for preservation purposes. Low-molecular weight (LMW) phthalate diesters function as plasticizers, fixatives or solvents in such products, but may also be found in small quantities as contaminants from plastic containers...... whether the difference is explained by increased use of the specific emollients that are used to treat pruritic and inflamed skin, and/or whether the impaired skin barrier allows chemicals to penetrate more easily. Moreover, the putative toxicological burden is unknown....

Radiation degradation of molasses pigment. 2. Molecular weight fraction

International Nuclear Information System (INIS)

Sawai, Teruko; Sekiguchi, Masayuki; Tanabe, Hiroko

1996-01-01

Water demand in Tokyo has increased rapidly. Because of the scarcity of water sources within the city, Tokyo is dependent on water from other prefectures. Recycling of municipal effluent is an effective means of coping with water shortage in Tokyo. We have studied the radiation treatment of waste water for recycling. The degradation of molasses pigments in waste water from yeast factory by radiation was investigated. The dialyzed molasses pigments and non-dialyzed samples in waste waters were compared in chromaticity, UV absorption, color different and COD. The dialysis and fractionation by permeable membrane were carried out with Seamless Cellulose tubing (Union Carbide Corporation) and spectra/Por membrane (Spectrum Medical Industries INC.) The TOC values decreased and the dark brown color faded with increasing dose. The high molecular weight components of molasses pigment were degraded to lower molecular weight substances and decomposed to carbon dioxide. The relationships between the value of chromaticity/TOC and molecular weight of molasses pigments were obtained by radiation. (author)

Molecular fingerprint of high fat diet induced urinary bladder metabolic dysfunction in a rat model.

Directory of Open Access Journals (Sweden)

Andreas Oberbach

Full Text Available AIMS/HYPOTHESIS: Diabetic voiding dysfunction has been reported in epidemiological dimension of individuals with diabetes mellitus. Animal models might provide new insights into the molecular mechanisms of this dysfunction to facilitate early diagnosis and to identify new drug targets for therapeutic interventions. METHODS: Thirty male Sprague-Dawley rats received either chow or high-fat diet for eleven weeks. Proteomic alterations were comparatively monitored in both groups to discover a molecular fingerprinting of the urinary bladder remodelling/dysfunction. Results were validated by ELISA, Western blotting and immunohistology. RESULTS: In the proteome analysis 383 proteins were identified and canonical pathway analysis revealed a significant up-regulation of acute phase reaction, hypoxia, glycolysis, β-oxidation, and proteins related to mitochondrial dysfunction in high-fat diet rats. In contrast, calcium signalling, cytoskeletal proteins, calpain, 14-3-3η and eNOS signalling were down-regulated in this group. Interestingly, we found increased ubiquitin proteasome activity in the high-fat diet group that might explain the significant down-regulation of eNOS, 14-3-3η and calpain. CONCLUSIONS/INTERPRETATION: Thus, high-fat diet is sufficient to induce significant remodelling of the urinary bladder and alterations of the molecular fingerprint. Our findings give new insights into obesity related bladder dysfunction and identified proteins that may indicate novel pathophysiological mechanisms and therefore constitute new drug targets.

Feasibility of MR urography in patients with urinary diversion

International Nuclear Information System (INIS)

Battal, Bilal; Kocaoglu, Murat; Ilica, Turan; Akgun, Veysel; Aydur, Emin; Dayanc, Murat

2011-01-01

The aims of this study were to determine the diagnostic value of MR urography and to compare the T2- and T1-weighted MR urography techniques in patients with urinary diversion. We retrospectively reviewed 19 MR urograms in 14 patients (13 male and one female, 8–77 years old, mean age: 54.2) with urinary diversion. Magnetic resonance urography examinations were performed with 1.5-T MR scanners. In addition to T2- and T1-weighted MR urography techniques, conventional T1- and T2-weighted axial and coronal sequences were also obtained. Collecting systems were evaluated in five segments (right proximal and distal collecting system, left proximal and distal collecting system and conduit or reservoir). Imaging features of the urinary collecting systems were evaluated with T2- and T1-weighted MR urography images. The clinical, laboratory data and follow-up imaging findings were regarded as standard. A cross table was formed to determine sensitivity, specificity and accuracy of MR urography techniques. T2-weighted MR urography, T1-weighted MR urography and combination of these two techniques could demonstrate 89.01, 87.65 and 93.83% of all collecting system segments, respectively. For the detection of the pathologic urinary segments, sensitivity, specificity and accuracy were 100, 95.29 and 95.6% in T2-weighted MR urography and 100, 93.42 and 93.82% in T1-weighted MR urography, respectively. Sensitivity, specificity and accuracy were 100% in combined T2- and T1-weighted MR urography technique. Magnetic resonance urography is an effective imaging method for the evaluation of the urinary system in patients with urinary diversion. T2-weighted MR urography alone has high sensitivity, specificity and accuracy, does not require intravenous contrast medium and can be obtained in 3–5 min. However, T1-weighted MR urography may provide additional information in some cases.

Role of Molecular Weight Distribution on Charge Transport in Semiconducting Polymers

KAUST Repository

Himmelberger, Scott

2014-10-28

© 2014 American Chemical Society. Model semiconducting polymer blends of well-controlled molecular weight distributions are fabricated and demonstrated to be a simple method to control intermolecular disorder without affecting intramolecular order or degree of aggregation. Mobility measurements exhibit that even small amounts of low molecular weight material are detrimental to charge transport. Trends in charge carrier mobility can be reproduced by a simple analytical model which indicates that carriers have no preference for high or low molecular weight chains and that charge transport is limited by interchain hopping. These results quantify the role of long polymer tie-chains and demonstrate the need for controlled polydispersity for achieving high carrier mobilities.

Elevated levels of high-molecular-weight adiponectin in type 1 diabetes

DEFF Research Database (Denmark)

Leth, H.; Andersen, K.K.; Frystyk, J.

2008-01-01

BACKGROUND: Several studies have shown that type 1 diabetic patients have elevated total levels of the adipocyte-derived adipocytokine adiponectin. However, adiponectin circulates in three different subforms, and the high-molecular-weight (HMW) subform is believed to be the primary biologically...... active form. The effects of the medium-molecular-weight (MMW) subform and the low-molecular-weight (LMW) subform are still unresolved. PURPOSE: The objective of the study was to investigate the distribution of the three molecular subforms of adiponectin in well-characterized groups of type 1 diabetics...... with varying degrees of nephropathy as well as in healthy control subjects. STUDY POPULATION: Two hundred seven individuals were included: 58 type 1 diabetics with normoalbuminuria, 46 with microalbuminuria, 46 with macroalbuminuria, and 57 matched controls. METHODS: The HMW, MMW, and LMW subforms were...

The urinary excretion of epidermal growth factor in the rat is reduced by aprotinin, a proteinase inhibitor

DEFF Research Database (Denmark)

Jørgensen, P E; Raaberg, Lasse; Poulsen, Steen Seier

1990-01-01

in vivo is processed by an aprotinin inhibitable proteinase. EGF is produced in the kidneys as a precursor with a molecular weight of approximately 130 kDa. In rat urine, nanomolar amounts of 6 kDa EGF are excreted per 24 h together with small amounts of high molecular weight forms of EGF. During i...... of immunoreactive EGF in the kidney tissue is increased after aprotinin administration (median amount 0.11 pmol EGF/mg protein versus less than 0.04 pmol EGF/mg protein, P less than 0.001). Neither the creatinine clearance, the total urinary protein output, nor the volume of urine produced was affected by aprotinin....

Urinary concentrations of bisphenol A and phthalate metabolites and weight change: a prospective investigation in US women.

Science.gov (United States)

Song, Y; Hauser, R; Hu, F B; Franke, A A; Liu, S; Sun, Q

2014-12-01

Both bisphenol A (BPA) and phthalates are known endocrine-disrupting chemicals for which there is widespread general population exposure. Human exposure occurs through dietary and non-dietary routes. Although animal studies have suggested a potential role of these chemicals in obesity, evidence from human studies is sparse and inconsistent, and prospective evidence is lacking. This study evaluated urinary concentrations of BPA and major phthalate metabolites in relation to prospective weight change. The study population was from the controls in a prospective case-control study of type 2 diabetes in the Nurses' Health Study (NHS) and NHSII. A total of 977 participants provided first-morning-void urine samples in 1996-2002. Urinary concentrations of BPA and nine phthalate metabolites were measured using liquid chromatography-mass spectrometry. Body weights were self-reported at baseline and updated biennially thereafter for 10 years. On average, the women gained 2.09 kg (95% confidence interval (CI), -2.27 to 6.80 kg) during the 10-year follow-up. In multivariate analysis with adjustment of lifestyle and dietary factors, in comparison with women in the lowest quartile of BPA concentration, those in the highest quartile had 0.23 kg per year (95% CI, 0.07-0.38 kg per year) greater weight gain during the 10-year follow-up (P-trend=0.02). Several phthalate metabolites, including phthalic acid, MBzP and monobutyl phthalate, were also associated with faster prospective weight gain in a dose-response fashion (P-trendfashion. These data are consistent with a potential role of BPA and phthalates in obesity, although more prospective data are needed to corroborate these observations.

High Molecular Weight Melanoidins from Coffee Brew

NARCIS (Netherlands)

Bekedam, E.K.; Schols, H.A.; Boekel, van T.; Smit, G.

2006-01-01

The composition of high molecular weight (HMw) coffee melanoidin populations, obtained after ethanol precipitation, was studied. The specific extinction coefficient (Kmix) at 280, 325, 405 nm, sugar composition, phenolic group content, nitrogen content, amino acid composition, and non-protein

Determination of viscosity-average molecular weight of chitosan using intrinsic viscosity measurement

International Nuclear Information System (INIS)

Norzita Yacob; Norhashidah Talip; Maznah Mahmud; Nurul Aizam Idayu Mat Sani; Nor Akma Samsuddin; Norafifah Ahmad Fabillah

2013-01-01

Determination of molecular weight by intrinsic viscosity measurement is a simple method for characterization of chitosan. To study the effect of radiation on molecular weight, chitosan was first irradiated using electron beam at different doses prior to measurement. Different concentrations of chitosan were prepared and measurement was done at room temperature. The flow time data was used to calculate the intrinsic viscosity by extrapolating the reduced viscosity to zero concentration. The value of intrinsic viscosity was then recalculated into the viscosity-average molecular weight using Mark-Houwink equation. (Author)

Determination of Viscosity-Average Molecular Weight of Chitosan using Intrinsic Viscosity Measurement

International Nuclear Information System (INIS)

Norzita Yacob; Norhashidah Talip; Maznah Mahmud

2011-01-01

Molecular weight of chitosan can be determined by different techniques such as Gel Permeation Chromatography (GPC), Static Light Scattering (SLS) and intrinsic viscosity measurement. Determination of molecular weight by intrinsic viscosity measurement is a simple method for characterization of chitosan. Different concentrations of chitosan were prepared and measurement was done at room temperature. The flow time data was used to calculate the intrinsic viscosity by extrapolating the reduced viscosity to zero concentration. The value of intrinsic viscosity was then recalculated into the viscosity-average molecular weight using Mark-Houwink equation. (author)

Role of static fluid MR urography in detecting post urinary diversion complications

Directory of Open Access Journals (Sweden)

Amr Farouk Ibrahim Moustafa

2018-06-01

Full Text Available Aim of work: The aim of the study was to assess the diagnostic performance of static MR urography in detection of post cystectomy complications & the ability of static fluid MR urography in visualization of urinary tract segments. Material & methods: We prospectively reviewed 21 MR urograms with urinary diversion. The most common surgical procedures included Ileal conduit & Ileocecal neobladder diversion.Magnetic resonance urography examinations were performed with 1.5-T MR scanners. T2 weighted (static fluid MR urography techniques were done, in addition to conventional T1- and T2-weighted axial and coronal sequences. Urinary tract was divided in different parts: pelvicalyceal systems, upper, mid and lower ureteric segments & the reservoir or conduit Imaging features of the urinary collecting systems were evaluated for their visualization and complications detection. Results: T2-weighted MR urography could demonstrate 95% of urinary tract segments & together with conventional MR sequences all urinary tract segments can be visualized. Urinary diversion related complications were encountered included in 15 patients (71.4% & no urological complications were seen in 6 patients (28.6%. Conclusion: Comprehensive T2-weighted MR urography is an effective imaging method for the visualization of the urinary system and detection of early and late postoperative complications in patients with urinary diversion. Keywords: MR urography, Urinary diversion, Cancer bladder

Low Molecular Weight Chitosan–Insulin Polyelectrolyte Complex: Characterization and Stability Studies

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Zakieh I. Al-Kurdi

2015-03-01

Full Text Available The aim of the work reported herein was to investigate the effect of various low molecular weight chitosans (LMWCs on the stability of insulin using USP HPLC methods. Insulin was found to be stable in a polyelectrolyte complex (PEC consisting of insulin and LMWC in the presence of a Tris-buffer at pH 6.5. In the presence of LMWC, the stability of insulin increased with decreasing molecular weight of LMWC; 13 kDa LMWC was the most efficient molecular weight for enhancing the physical and chemical stability of insulin. Solubilization of insulin-LMWC polyelectrolyte complex (I-LMWC PEC in a reverse micelle (RM system, administered to diabetic rats, results in an oral delivery system for insulin with acceptable bioactivity.

Media optimization for elevated molecular weight and mass production of pigment-free pullulan.

Science.gov (United States)

Yu, Xiaoliu; Wang, Yulei; Wei, Gongyuan; Dong, Yingying

2012-07-01

In this study, an Aureobasidium pullulans SZU 1001 mutant, deficient in pigment production, was screened by complex UV and γ-ray mutagenesis. Medium composition optimization for increased pullulan molecular weight and production was conducted using this mutant. Six nutrients: yeast extract, (NH4)2SO4, K2HPO4, NaCl, MgSO4·7H2O and CaCl2 were detected within pullulan production in flasks. It is shown that NaCl and K2HPO4 have significant influences on molecular weight of pullulan, while yeast extract and (NH4)2SO4 significantly affect pullulan yield. To achieve a higher molecular weight and more efficient pullulan production, a response surface methodology approach was introduced to predict an optimal nutrient combination. A molecular weight of 5.74 × 10(6) and pullulan yield on glucose of 51.30% were obtained under batch pullulan fermentation with the optimized media, which increased molecular weight and pullulan production by 97.25% and 11.04%, respectively compared with the control media. Copyright © 2012 Elsevier Ltd. All rights reserved.

Sintering of ultra high molecular weight polyethylene

Indian Academy of Sciences (India)

Abstract. Ultra high molecular weight polyethylene (UHMWPE) is a high performance polymer having low coefficient of friction, good abrasion resistance, good chemical ... In this study, we report our results on compaction and sintering behaviour of two grades of UHMWPE with reference to the powder morphology, sintering ...

Molecular weight kinetics and chain scission models for dextran polymers during ultrasonic degradation.

Science.gov (United States)

Pu, Yuanyuan; Zou, Qingsong; Hou, Dianzhi; Zhang, Yiping; Chen, Shan

2017-01-20

Ultrasonic degradation of six dextran samples with different initial molecular weights (IMW) has been performed to investigate the degradation behavior and chain scission mechanism of dextrans. The weight-average molecular weight (Mw) and polydispersity index (D value) were monitored by High Performance Gel Permeation Chromatography (HPGPC). Results showed that Mw and D value decreased with increasing ultrasonic time, resulting in a more homologous dextran solution with lower molecular weight. A significant degradation occurred in dextrans with higher IMW, particularly at the initial stage of the ultrasonic treatment. The Malhotra model was found to well describe the molecular weight kinetics for all dextran samples. Experimental data was fitted into two chain scission models to study dextran chain scission mechanism and the model performance was compared. Results indicated that the midpoint scission model agreed well with experimental results, with a linear regression factor of R 2 >0.99. Copyright © 2016 Elsevier Ltd. All rights reserved.

Alkyl cross-linked low molecular weight polypropyleneimine dendrimers as efficient gene delivery vectors

Directory of Open Access Journals (Sweden)

Faezeh Moghadam Ariaee

2016-10-01

Conclusion: Our results indicated that oligomerization of low molecular weight PPI (PPI G2-alkyl-PPI G2 conjugate could be an approach to increase the transfection efficiency and to lower the cytotoxicity of low molecular weight polycations.

Control of molecular weight distribution in synthesis of poly(2-hydroxyethyl methacrylate) using ultrasonic irradiation.

Science.gov (United States)

Kubo, Masaki; Kondo, Takayuki; Matsui, Hideki; Shibasaki-Kitakawa, Naomi; Yonemoto, Toshikuni

2018-01-01

Poly(2-hydroxyethyl methacrylate) (PHEMA) was synthesized using ultrasonic irradiation without any chemical initiator. The effect of the ultrasonic power intensity on the time course of the conversion to polymer, the number average molecular weight, and the polydispersity were investigated in order to synthesize a polymer with a low molecular weight distribution (i.e., low polydispersity). The conversion to polymer increased with time. A higher ultrasonic power intensity resulted in a faster reaction rate. The number average molecular weight increased during the early stage of the reaction and then gradually decreased with time. A higher ultrasonic intensity resulted in a faster degradation rate of the polymer. The polydispersity decreased with time. This was because the degradation rate of a polymer with a higher molecular weight was faster than that of a polymer with a lower molecular weight. A polydispersity below 1.3 was obtained under ultrasonic irradiation. By changing the ultrasonic power intensity during the reaction, the number average molecular weight can be controlled while maintaining low polydispersity. When the ultrasonic irradiation was halted, the reactions stopped and the number average molecular weight and polydispersity did not change. On the basis of the experimental results, a kinetic model for synthesis of PHEMA under ultrasonic irradiation was constructed considering both polymerization and polymer degradation. The kinetic model was in good agreement with the experimental results for the time courses of the conversion to polymer, the number average molecular weight, and the polydispersity for various ultrasonic power intensities. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of solvent-free offset ink using vegetable oil esters and high molecular-weight resin.

Science.gov (United States)

Park, Jung Min; Kim, Young Han; Kim, Sung Bin

2013-01-01

In the development of solvent-free offset ink, the roles of resin molecular weight and used solvent on the ink performance were evaluated by examining the relationship between the various properties of resin and solvent and print quality. To find the best performing resin, the soy-oil fatty acid methyl ester (FAME) was applied to the five modified-phenolic resins having different molecular weights. It is found from the experimental results that the ink made of higher molecular weight and better solubility resin gives better printability and print quality. It is because larger molecular weight resin with better solubility gives higher rate of ink transfer. From the ink application of different esters to high molecular weight resin, the best printing performance was yielded from the soy-oil fatty acid butyl ester (FABE). It is due to its high kinematic viscosity resulting in the smallest change of ink transfer weight upon multiple number of printing, which improves the stability of ink quality.

Molecular weight-dependent degradation and drug release of surface-eroding poly(ethylene carbonate).

Science.gov (United States)

Bohr, Adam; Wang, Yingya; Harmankaya, Necati; Water, Jorrit J; Baldursdottír, Stefania; Almdal, Kristoffer; Beck-Broichsitter, Moritz

2017-06-01

Poly(ethylene carbonate) (PEC) is a unique biomaterial showing significant potential for controlled drug delivery applications. The current study investigated the impact of the molecular weight on the biological performance of drug-loaded PEC films. Following the preparation and thorough physicochemical characterization of diverse PEC (molecular weights: 85, 110, 133, 174 and 196kDa), the degradation and drug release behavior of rifampicin- and bovine serum albumin-loaded PEC films was investigated in vitro (in the presence and absence of cholesterol esterase), in cell culture (RAW264.7 macrophages) and in vivo (subcutaneous implantation in rats). All investigated samples degraded by means of surface erosion (mass loss, but constant molecular weight), which was accompanied by a predictable, erosion-controlled drug release pattern. Accordingly, the obtained in vitro degradation half-lives correlated well with the observed in vitro half-times of drug delivery (R 2 =0.96). Here, the PEC of the highest molecular weight resulted in the fastest degradation/drug release. When incubated with macrophages or implanted in animals, the degradation rate of PEC films superimposed the results of in vitro incubations with cholesterol esterase. Interestingly, SEM analysis indicated a distinct surface erosion process for enzyme-, macrophage- and in vivo-treated polymer films in a molecular weight-dependent manner. Overall, the molecular weight of surface-eroding PEC was identified as an essential parameter to control the spatial and temporal on-demand degradation and drug release from the employed delivery system. Copyright © 2017 Elsevier B.V. All rights reserved.

An evaluation of the effects of PEO/PEG molecular weights on extruded alumina rods

Science.gov (United States)

Bolger, Nancy Beth

1998-12-01

Alumina rods were piston extruded from bodies containing polyethylene glycols (PEGs) and polyethylene oxides (PEOs) with molecular weights ranging from 1,300 to 3,800,000 g/mol. A blend of aluminas possessing different particle size distributions was evaluated with regard to its extrusion pressure by varying the amount of PEG/PEO addition. Behavior exhibited by the alumina blend was dependent upon the additive that was used. The higher molecular weight binders with average molecular weight of 200,000 g/mol and 3,350,000 g/mol displayed the most severe behaviors of near dilatant and dilatant respectively. Physical properties of the green and fired states, as well as the binder burnout, were investigated with the changing additions. Correlation between the green and fired strengths and the changing molecular weights were examined. The additive present influenced the surface properties of the rods, which affected the green strengths. The highest average molecular weight polyethylene glycols showed higher green strengths, while the lowest green strengths were observed for the high molecular weight polyethylene oxides. Fired strengths generally ranged from approximately 12,000 psi to 16,000 psi for additive batches. Alumina pellets containing twelve separate combinations of polyethylene glycol with polyethylene oxide were dry pressed. Physical properties of the green and fired states were examined. Statistical analysis was performed upon the data and seven combinations of polyethylene glycol with polyethylene oxide were deemed significant. These combinations in conjunction with the same alumina blend were then piston extruded. The addition of polyethylene glycol reduced the near dilatant behavior exhibited by the 200,000 g/mol average molecular weight polyethylene oxide. Dilatant behavior was completely eliminated from the 3,350,000 g/mol average molecular weight polyethylene oxide batches. Physical properties of the green and fired states were again investigated with

Low-molecular-weight chitosans: Preparation and characterization

Czech Academy of Sciences Publication Activity Database

Tishchenko, Galina; Šimůnek, Jiří; Brus, Jiří; Netopilík, Miloš; Pekárek, Michal; Walterová, Zuzana; Koppová, Ingrid; Lenfeld, Jiří

2011-01-01

Roč. 86, č. 2 (2011), s. 1077-1081 ISSN 0144-8617 R&D Projects: GA ČR(CZ) GA525/08/0803 Institutional research plan: CEZ:AV0Z40500505; CEZ:AV0Z50450515 Keywords : low-molecular-weight chitosans * chitooligosaccharides * oxidative depolymerization Subject RIV: ED - Physiology Impact factor: 3.628, year: 2011

Preclinical studies of lymphographic applilcation of 99mTc-dextrans of different molecular weight

International Nuclear Information System (INIS)

Lamka, J.; Kvetina, J.; Kafka, P.

1986-01-01

In a preclinical investigation on rabbits the distribution was tested of dextrans of two molecular weights (40,000 and 70,000) with regard to their use as a carrier in indirect lymphography. The tests showed that both 99m Tc-dextrans achieve high ratios of lymph/blood levels. It is suggested that for clinical work it is better to use dextran with a molecular weight of 70,000 than that with a molecular weight of 40,000. (author)

Low-molecular-weight heparins: pharmacologic profile and product differentiation.

Science.gov (United States)

Fareed, J; Jeske, W; Hoppensteadt, D; Clarizio, R; Walenga, J M

1998-09-10

The interchangeability of low-molecular-weight heparins (LMWHs) has been the subject of discussion since these products were first introduced for the prophylaxis of deep vein thrombosis. Experimental evidence now exists to show that LMWHs differ from each other in a number of characteristics. Products have been differentiated on the basis of molecular weight and biologic properties, but only limited information derived from the clinical setting is available. Potency has been described on the basis of anti-Factor Xa activity, but at equivalent anti-Xa activities, the anti-Factor IIa activity of different products shows marked variations. At the relatively small doses used for the management of postsurgical deep vein thrombosis, the effect of these interproduct differences may be relatively minor, but as LMWHs are developed for therapeutic use at much higher doses, such differences may become clinically important. Variations in safety and efficacy reported in clinical trials of LMWHs may reflect the known differences in their molecular composition and pharmacologic properties.

Low Molecular Weight Norbornadiene Derivatives for Molecular Solar-Thermal Energy Storage.

Science.gov (United States)

Quant, Maria; Lennartson, Anders; Dreos, Ambra; Kuisma, Mikael; Erhart, Paul; Börjesson, Karl; Moth-Poulsen, Kasper

2016-09-05

Molecular solar-thermal energy storage systems are based on molecular switches that reversibly convert solar energy into chemical energy. Herein, we report the synthesis, characterization, and computational evaluation of a series of low molecular weight (193-260 g mol(-1) ) norbornadiene-quadricyclane systems. The molecules feature cyano acceptor and ethynyl-substituted aromatic donor groups, leading to a good match with solar irradiation, quantitative photo-thermal conversion between the norbornadiene and quadricyclane, as well as high energy storage densities (396-629 kJ kg(-1) ). The spectroscopic properties and energy storage capability have been further evaluated through density functional theory calculations, which indicate that the ethynyl moiety plays a critical role in obtaining the high oscillator strengths seen for these molecules. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Characteristics and bioactivities of different molecular weight polysaccharides from camellia seed cake.

Science.gov (United States)

Xu, Zhou; Li, Xu; Feng, Shiling; Liu, Jing; Zhou, Lijun; Yuan, Ming; Ding, Chunbang

2016-10-01

Four polysaccharides, namely COP-1, COP-2, COP-3 and COP-4, were ultrafiltrated from crud Camellia oleifera seed cake polysaccharides (COP-c), purified, and characterized, including the determination of antioxidant and antiproliferative activities. Their molecular weights were 7.9, 36, 83 and 225kDa, respectively. All COPs showed the similar FT-IR spectrums, but significant differentials in monosaccharide components. COP-2 exhibited the highest radical scavenging abilities. COP-1 has the strongest metal chelating capabilities. Although with higher molecular weight, COP-4 showed the poorest antioxidant abilities. These results suggested appreciate molecular weight COP possessed a better antioxidant activities. Additionally, all COPs had non-significant antiproliferative abilities in HaLa and HepG2 cells. Copyright © 2016 Elsevier B.V. All rights reserved.

Profiling of the Molecular Weight and Structural Isomer Abundance of Macroalgae-Derived Phlorotannins

Directory of Open Access Journals (Sweden)

Natalie Heffernan

2015-01-01

Full Text Available Phlorotannins are a group of complex polymers of phloroglucinol (1,3,5-trihydroxybenzene unique to macroalgae. These phenolic compounds are integral structural components of the cell wall in brown algae, but also play many secondary ecological roles such as protection from UV radiation and defense against grazing. This study employed Ultra Performance Liquid Chromatography (UPLC with tandem mass spectrometry to investigate isomeric complexity and observed differences in phlorotannins derived from macroalgae harvested off the Irish coast (Fucus serratus, Fucus vesiculosus, Himanthalia elongata and Cystoseira nodicaulis. Antioxidant activity and total phenolic content assays were used as an index for producing phlorotannin fractions, enriched using molecular weight cut-off dialysis with subsequent flash chromatography to profile phlorotannin isomers in these macroalgae. These fractions were profiled using UPLC-MS with multiple reaction monitoring (MRM and the level of isomerization for specific molecular weight phlorotannins between 3 and 16 monomers were determined. The majority of the low molecular weight (LMW phlorotannins were found to have a molecular weight range equivalent to 4–12 monomers of phloroglucinol. The level of isomerization within the individual macroalgal species differed, resulting in substantially different numbers of phlorotannin isomers for particular molecular weights. F. vesiculosus had the highest number of isomers of 61 at one specific molecular mass, corresponding to 12 phloroglucinol units (PGUs. These results highlight the complex nature of these extracts and emphasize the challenges involved in structural elucidation of these compounds.

Determination of the Molecular Weight of Low-Molecular-Weight Heparins by Using High-Pressure Size Exclusion Chromatography on Line with a Triple Detector Array and Conventional Methods

Directory of Open Access Journals (Sweden)

Antonella Bisio

2015-03-01

Full Text Available The evaluation of weight average molecular weight (Mw and molecular weight distribution represents one of the most controversial aspects concerning the characterization of low molecular weight heparins (LMWHs. As the most commonly used method for the measurement of such parameters is high performance size exclusion chromatography (HP-SEC, the soundness of results mainly depends on the appropriate calibration of the chromatographic columns used. With the aim of meeting the requirement of proper Mw standards for LMWHs, in the present work the determination of molecular weight parameters (Mw and Mn by HP-SEC combined with a triple detector array (TDA was performed. The HP-SEC/TDA technique permits the evaluation of polymeric samples by exploiting the combined and simultaneous action of three on-line detectors: light scattering detectors (LALLS/RALLS; refractometer and viscometer. Three commercial LMWH samples, enoxaparin, tinzaparin and dalteparin, a γ-ray depolymerized heparin (γ-Hep and its chromatographic fractions, and a synthetic pentasaccharide were analysed by HP-SEC/TDA. The same samples were analysed also with a conventional HP-SEC method employing refractive index (RI and UV detectors and two different chromatographic column set, silica gel and polymeric gel columns. In both chromatographic systems, two different calibration curves were built up by using (i γ-Hep chromatographic fractions and the corresponding Mw parameters obtained via HP-SEC/TDA; (ii the whole γ-Hep preparation with broad Mw dispersion and the corresponding cumulative distribution function calculated via HP-SEC/TDA. In addition, also a chromatographic column calibration according to European Pharmacopoeia indication was built up. By comparing all the obtained results, some important differences among Mw and size distribution values of the three LMWHs were found with the five different calibration methods and with HP-SEC/TDA method. In particular, the detection of

Synthesis and properties of aqueous polyurethane dispersions: Influence of molecular weight of polyethylene glycol

Energy Technology Data Exchange (ETDEWEB)

Mumtaz, Fatima; Zuber, Mohammad; Zia, Khalid Mahmood [Government College University, Faisalabad (Pakistan); Jamil, Tahir [University of the Punjab, Lahore (Pakistan); Hussain, Rizwan [National Engineering and Scientific Commission (NESCOM), Islamabad (Pakistan)

2013-12-15

Aqueous polyurethane dispersions (PUDs) have recently emerged as important alternatives to their solvent-based counterparts for various applications due to increasing health and environmental awareness. A series of aqueous polyurethane dispersions containing carboxylate anion as hydrophilic pendant groups were synthesized through step growth polymerization reaction using hexamethylene diisocyanate (HDI), 1,4-butanediol (1,4-BDO), dimethylol propionic acid (DMPA) and polyethylene glycol (PEG) of different molecular weight. Effect of PEG molecular weight was investigated on molecular structure, contact angle measurement, and physical and adhesive properties of PU emulsions. Fourier transform infrared spectroscopy (FT-IR) was used to check the completion of polymerization reaction. Contact angle measurement indicated that the hydrophilicity of polymer increases by increasing molecular weight of PEG with a corresponding decrease in contact angle. Results of T-peel test showed a decrease in peel strength by increasing molecular weight of PEG. Moreover, solid contents%, drying time and storage stability suggested fast drying properties and greater stability of aqueous PU dispersions.

How does the preparation of rye porridge affect molecular weight distribution of extractable dietary fibers?

Science.gov (United States)

Rakha, Allah; Aman, Per; Andersson, Roger

2011-01-01

Extractable dietary fiber (DF) plays an important role in nutrition. This study on porridge making with whole grain rye investigated the effect of rest time of flour slurries at room temperature before cooking and amount of flour and salt in the recipe on the content of DF components and molecular weight distribution of extractable fructan, mixed linkage (1→3)(1→4)-β-d-glucan (β-glucan) and arabinoxylan (AX) in the porridge. The content of total DF was increased (from about 20% to 23% of dry matter) during porridge making due to formation of insoluble resistant starch. A small but significant increase in the extractability of β-glucan (P = 0.016) and AX (P = 0.002) due to rest time was also noted. The molecular weight of extractable fructan and AX remained stable during porridge making. However, incubation of the rye flour slurries at increased temperature resulted in a significant decrease in extractable AX molecular weight. The molecular weight of extractable β-glucan decreased greatly during a rest time before cooking, most likely by the action of endogenous enzymes. The amount of salt and flour used in the recipe had small but significant effects on the molecular weight of β-glucan. These results show that whole grain rye porridge made without a rest time before cooking contains extractable DF components maintaining high molecular weights. High molecular weight is most likely of nutritional importance.

How Does the Preparation of Rye Porridge Affect Molecular Weight Distribution of Extractable Dietary Fibers?

Directory of Open Access Journals (Sweden)

Roger Andersson

2011-05-01

Full Text Available Extractable dietary fiber (DF plays an important role in nutrition. This study on porridge making with whole grain rye investigated the effect of rest time of flour slurries at room temperature before cooking and amount of flour and salt in the recipe on the content of DF components and molecular weight distribution of extractable fructan, mixed linkage (1→3(1→4-β-D-glucan (β-glucan and arabinoxylan (AX in the porridge. The content of total DF was increased (from about 20% to 23% of dry matter during porridge making due to formation of insoluble resistant starch. A small but significant increase in the extractability of β-glucan (P = 0.016 and AX (P = 0.002 due to rest time was also noted. The molecular weight of extractable fructan and AX remained stable during porridge making. However, incubation of the rye flour slurries at increased temperature resulted in a significant decrease in extractable AX molecular weight. The molecular weight of extractable β-glucan decreased greatly during a rest time before cooking, most likely by the action of endogenous enzymes. The amount of salt and flour used in the recipe had small but significant effects on the molecular weight of β-glucan. These results show that whole grain rye porridge made without a rest time before cooking contains extractable DF components maintaining high molecular weights. High molecular weight is most likely of nutritional importance.

Clinical effects of low-molecular-weight heparin combined with ...

African Journals Online (AJOL)

Tropical Journal of Pharmaceutical Research August 2016; 15 (8): 1787-1792 ... Keywords: Acute pancreatitis, Low-molecular-weight heparin, Multiple organ function syndrome,. APACHE II score ... mediators by lowering the expression of.

Effects of Hofmeister Anions on the LCST of PNIPAM as a Function of Molecular Weight

Science.gov (United States)

Zhang, Yanjie; Furyk, Steven; Sagle, Laura B.; Cho, Younhee; Bergbreiter, David E.; Cremer, Paul S.

2008-01-01

The effect of a series of sodium salts on the lower critical solution temperature (LCST) of poly(N-isopropylacrylamide), PNIPAM, was investigated as a function of molecular weight and polymer concentration with a temperature gradient microfluidic device under a dark-field microscope. In solutions containing sufficient concentrations of kosmotropic anions, the phase transition of PNIPAM was resolved into two separate steps for higher molecular weight samples. The first step of this two step transition was found to be sensitive to the polymer’s molecular weight and solution concentration, while the second step was not. Moreover, the binding of chaotropic anions to the polymer was also influenced by molecular weight. Both sets of results could be explained by the formation of intramolecular and intermolecular hydrogen-bonding between polymer chains. By contrast, the hydrophobic hydration of the isopropyl moieties and polymer backbone was found to be unaffected by either the polymer’s molecular weight or solution concentration. PMID:18820735

Calibration of low molecular weight polypeptides by sodium dodecylsulphate polyacrylamide gel electrophoresis

International Nuclear Information System (INIS)

Glyn, M.C.P.; Bull, J.; Wright, R.

1982-01-01

Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) is a technique commonly used in determining molecular weights of large proteins and peptides. This technique is used to analyse viral peptides, available in amounts too small to be monitored by an ultraviolet spectrophotometer. An experiment is described (with the limiting factor to use the SDS-PAGE technique), to determine the molecular weight peptides and the results are given to fit the linear relationship log M=4.286 - 0.42 V(e)/V(o). The results given by the SDS-PAGE system, described in the article, show that the experimental values describe a linear relationship with good resolution of low molecular weight peptides in the range 3 000 to 14 000 and that a partial cyanogen bromide digest of cytochrome c is suitable for calibration standards

Effect of Molecular Weight on the Properties of Liquid Epoxidized Natural Rubber Acrylate (LENRA)/ Silica Hybrid Composites

International Nuclear Information System (INIS)

Eda Yuhana Ariffin; Azizan Ahmad; Dahlan Mohd; Mahathir Mohamed

2011-01-01

This paper reports on the effect of molecular weight on the morphological and mechanical properties of liquid epoxidized natural rubber acrylate (LENRA)/ silica hybrid composites prepared by sol-gel technique. The sol-gel reaction was conducted at different concentration of tetraethyl orthosilicate (TEOS), used as a precursor of silica. TEOS were introduced in 10, 20, 30, 40 and 50 parts per hundred rubber (phr) in the composites. Two different molecular weights of ENR were used to study the effect of molecular weight on the mechanical and morphological properties of the compounds. These compounds were cured by ultraviolet (UV) irradiation. The mechanical properties were studied through pendulum hardness and scratch tests. Higher molecular weight of ENR showed better mechanical properties than lower molecular weight. Transmission electron microscope was used to determine the silica size and to study the distribution and dispersion of the silica particles. High molecular weight showed greater distribution and dispersion of silica particles with diameter of 13 - 256 nm. Morphological and mechanical properties of LENRA/ silica hybrid composites were improved by using high molecular weight of ENR. (author)

Steroidogenic activity of high molecular weight forms of ACTH

International Nuclear Information System (INIS)

Gasson, J.C.

1979-01-01

The relative steroidogenic potencies of high molecular weight forms of adrenocorticotropic hormone (ACTH) were investigated using in vitro bioassays. In order to prepare pools of separated pro-ACTH/endorphin, ACTH biosynthetic intermediate and glycosylated ACTH (1-39), the protein present in serum-free tissue culture medium obtained from cultured AtT-20/D-16v mouse pituitary tumor cells was concentrated and fractionated by gel filtration. Based on sodium dodecyl sulfate polyacrylamide gel electrophoresis, over 97% of the immunoactive ACTH in each pool had the appropriate molecular weight. Suspensions of isolated rat and guinea pig adrenal cortical cells were prepared by enzymatic dissociation and mechanical dispersion. Cells were incubated in complete tissue culture medium overnight then used in a 2 hour steroid production assay. Synthetic hACTH(1-39) was used as a bioassay and immunoassay standard. The amounts of pro-ACTH/endorphin, ACTH biosynthetic intermediate and glycosylated ACTH(1-39) bioassayed were estimated by ACTH(17-24) radioimmunoassay. All three high molecular weight forms of ACTH were capable of stimulating the same maximal level of steroidogenesis, by both isolated rat and guinea pig adrenal cells, as hACTH(1-39). Glycosylated ACTH(1-39) was equipotent with hACTH(1-39); pro-ACTH/endorphin and ACTH biosynthetic intermediate were two orders of magnitude less potent than hACTH(1-39) in both bioassay systems

Aromatic polymers of increased resistance to flow and molecular weight obtained by irradiation

International Nuclear Information System (INIS)

Staniland, P.A.; Jarrett, G.

1976-01-01

Aromatic polymers of increased resistance to flow and increased molecular weight are obtained by irradiation using β rays or gamma rays at temperatures up to 400 0 C of an aromatic polymer whose molecular chains comprise benzenoid groups and bivalent linking groups, and where irradiation is gamma rays by heating subsequent to irradiation at 200 0 C to 400 0 C. The polymeric materials having increased molecular weight are useful for coating non-cooking surfaces of cookware

Microbiome in the urinary system—a review

Directory of Open Access Journals (Sweden)

Jane Tang

2017-03-01

Full Text Available Urine was considered sterile in healthy individuals for many years, and the presence of bacteria signified urinary tract infection. With the development of Expanded Quantitative Urine Culture (EQUC and utilization of molecular techniques, the previous clinical dogma is no longer valid. Instead, healthy people harbor a considerable microbial community, or microbiota, in their urinary systems. Similar to other physiological niches where microbiota contribute to the health status of their hosts, recent studies demonstrated different microbial populations also play a crucial role in urinary health of individuals. Understanding urinary microbiome thus allows a more holistic approach in the diagnosis, treatment, and prevention of diseases and disorders in urinary system. This review article provides an overview of current findings in urinary microbiome and discusses some of the gaps for future research.

Effect of the molecular weight of a neutral polysaccharide on soy protein gelation.

Science.gov (United States)

Monteiro, Sónia R; Lopes-da-Silva, José A

2017-12-01

The effects of galactomannans with different molecular weights on the heat-induced gelation characteristics of soybean protein were investigated using dynamic small-strain rheometry, under conditions where the proteins carry a net negative charge (pH7). Microstructure of the resulting gels was investigated by confocal laser scanning microscopy. Phase-separated systems were obtained with different morphologies and degree of phase separation, depending on both biopolymer concentrations and polysaccharide molecular weight. In general, a gelling enhancing effect on soy proteins was verified, despite extensive phase-separation processes observed at the higher polysaccharide molecular weight. This effect was demonstrated by an increase of the gelation rate, a decrease in the temperature at the onset of gelation, and an increase of gel stiffness and elastic character, with the length of polysaccharide chains. Overall, the results obtained established that the judicious selection of the galactomannan molecular weight may be used to modify the structure and gelation properties of soy proteins, originating a diversity of rheological characteristics and microstructures that will impact on the design of novel food formulations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acrylate oligomers in ultraviolet cured PSA's glass transition, molecular weight versus peel strength

International Nuclear Information System (INIS)

Miller, H.C.

1999-01-01

Typically those not skilled in the art relate Glass Transition Temperature to Pressure Sensitive Adhesives. You need a low Tg material to prepare good pressure sensitive adhesives. This report deals with a wide range acrylate terminated oligomers in a standard formulation. Molecular weight, chemical structure variations are examined versus the Glass Transition of the oligomers and final peel strength. Each formulated adhesive will require unique oligomer properties to reach one hundred newtons per 100 millimeters (5.71 pounds per square inch) peel strength. Excellent peel strengths may be obtained with oligomer molecular weight ranging from six thousand to one thousand molecular weight and glass transition temperatures ranging from minus seventy four degrees centigrade up to thirteen degrees centigrade

High Molecular Weight Polymers in the New Chemicals Program

Science.gov (United States)

There are three categories or types of High Molecular Weight (HMW, 10,000 daltons) polymers typically reviewed by the New Chemicals Program: Soluble, insoluble, and water absorbing. Each of the three types are treated differently.

Irradiated aromatic polysulphones of increased flow resistance and molecular weight

International Nuclear Information System (INIS)

Staniland, P.A.; Jarrett, W.G.

1976-01-01

Aromatic polymers of increased resistance to flow and molecular weight are obtained by irradiation using β-rays or γ-rays at temperatures up to 400 0 C of an aromatic polymer whose molecular chains comprise benzenoid groups and bivalent linking groups, and where irradiation is γ-rays by heating subsequent to irradiation at 200 to 400 0 C

The Effect of Polymer Molecular Weight on Citrate Crosslinked ...

African Journals Online (AJOL)

Erah

Purpose: To develop citrate crosslinked chitosan films using chitosan of different molecular weights. (MW) in .... left to stand until trapped air bubbles ... blotted out carefully with filter paper from the .... potential as biodegradable stent coatings. J.

Hyaluronic acid-coated chitosan nanoparticles: molecular weight-dependent effects on morphology and hyaluronic acid presentation.

Science.gov (United States)

Almalik, Abdulaziz; Donno, Roberto; Cadman, Christopher J; Cellesi, Francesco; Day, Philip J; Tirelli, Nicola

2013-12-28

Chitosan nanoparticles are popular carriers for the delivery of macromolecular payloads, e.g. nucleic acids. In this study, nanoparticles were prepared via complexation with triphosphate (TPP) anions and were successively coated with hyaluronic acid (HA). Key variables of the preparative process (e.g. chitosan and HA molecular weight) were optimised in view of the maximisation of loading with DNA, of the Zeta potential and of the dimensional stability, and the resulting particles showed excellent storage stability. We have focused on the influence of chitosan molecular weight on nanoparticle properties. Larger molecular weight increased their porosity (=decreased cross-link density), and this caused also larger dimensional changes in response to variations in osmotic pressure or upon drying. The dependency of nanoparticle porosity on chitosan molecular weight had a profound effect on the adsorption of HA on the nanoparticles; HA was apparently able to penetrate deeply into the more porous high molecular weight (684 kDa) chitosan nanoparticles, while it formed a corona around those composed of more densely cross-linked low molecular weight (25 kDa) chitosan. Atomic Force Microscopy (AFM) allowed not only to highlight the presence of this corona, but also to estimate its apparent thickness to about 20-30 nm (in a dry state). The different morphology has a significant effect on the way HA is presented to biomolecules, and this has specific relevance in relation to interactions with HA receptors (e.g. CD44) that influence kinetics and mechanism of nanoparticle uptake. Finally, it is worth to mention that chitosan molecular weight did not appear to greatly affect the efficiency of nanoparticle loading with DNA, but significantly influenced its chitosanase-triggered release, with high molecular chitosan nanoparticles seemingly more prone to degradation by this enzyme. © 2013.

The effect of low molecular weight multifunctional additives on heavy oil viscosity

Energy Technology Data Exchange (ETDEWEB)

Oldenburg, T.B.P.; Yarranton, H.W.; Larter, S.R. [Calgary Univ., AB (Canada)

2010-07-01

Crude oils contain many small multifunctional low molecular weight components that act as linking molecules between larger functionalized species. The linkage molecules have a significant impact on the flow properties of hydrocarbon systems. This study investigated the use of a low molecular weight multiheteroatom species (LMWMH) as a molecular Velcro linking high molecular weight components together. LMWMH species were added to Albertan bitumens and heavy oil, and their impact on viscosity was investigated. Results of the experimental studies were then compared with the effects of hydrocarbon solvents on similar samples. The LMWMH species included bifunctional species and analogous alkyl and aryl monoamines that acted as blocking molecules to hinder the association of larger petroleum species. Density and viscosity measurements were conducted. A correlation method was used to predict the viscosity of the solvent-diluted heavy oil and bitumen samples. The study showed that of the tested additives, only aniline demonstrated an additional viscosity-reducing effect. The aniline inhibited asphaltene association and is a promising candidate for enhanced in-situ bitumen viscosity reduction. 23 refs., 4 tabs.

Molecular weight changes induced in an anionic polydimethylsiloxane by gamma irradiation in vacuum

International Nuclear Information System (INIS)

Satti, Angel J.; Andreucetti, Noemi A.; Ciolino, Andres E.; Vitale, Cristian; Sarmoria, Claudia; Valles, Enrique M.

2010-01-01

An anionic almost monodisperse linear polydimethylsiloxane (PDMS) was subjected to gamma irradiation under vacuum at room temperature. The molecular weight changes induced by the radiation process have been investigated using size exclusion chromatography (SEC) with refraction index (RI) and multi angle laser light scattering (MALLS) detectors, to obtain the number and weight average molecular weights of the irradiated samples. The analysis of the data indicates that crosslinking reactions predominated over scission reactions. The results obtained by an SEC-RI have confirmed the presence of small, but measurable amounts of scission. A previously developed mathematical model of the irradiation process that accounts for simultaneous scission and crosslinking and allows for both H- and Y-crosslinks, fitted well the measured molecular weight data. This prediction is in accordance with the experimental data obtained by 29 Si-Nuclear Magnetic Resonance spectroscopy (NMR) and previously reported data for commercial linear PDMS ().

Emulsifier-free emulsion polymerization of tetrafluoroethylene by radiation. IV. Effects of additives on Polymer molecular weight

International Nuclear Information System (INIS)

Watanabe, T.; Suwa, T.; Okamoto, J.; Machi, S.

1979-01-01

Poly(tetrafluoroethylene)(PTFE) of high molecular weight, 4.5 x 10 7 , was incidentally obtained at earlier study of an emulsifier-free emulsion polymerization of tetrafluoroethylene by radiation. In order to clarify this phenomenon, the effects of additives, in particular radical scavengers, on the molecular weight of PTFE and its polymerization behavior were studied. It was found that the molecular weight of PTFE is increased by the addition of hydroquinone, benzoquinone, α-pinene, dl-limonene, and ethylenediamine but is decreased by oxygen and triethylamine. A PTFE latex with molecular weight higher than 2 x 10 7 was obtained in the presence of hydroquinone. It is concluded that additives such as hydroquinone and benzaquinone, which rapidly scavenge the primary radicals (OH, H, and e/sub aq/ - ) in the aqueous phase but not the growing polymer radicals in PTFE particles, are most effective in increasing the molecular weight

Low molecular weight heparin versus unfractionated heparin in the initial treatment of venous thromboembolism

NARCIS (Netherlands)

Hettiarachchi, R. J.; Prins, M. H.; Lensing, A. W.; Buller, H. R.

1998-01-01

In this review, we analyze data from randomized trials in which low molecular weight heparin was compared with unfractionated heparin, both to estimate the treatment effect of low molecular weight heparin in the initial treatment of venous thromboembolism and to evaluate the effect of the varied

Relationship between molecular weight, monosaccharide composition and immunobiologic activity of Astragalus polysaccharides.

Science.gov (United States)

Jiang, Yiping; Qi, Xiaohui; Gao, Kai; Liu, Wenjun; Li, Na; Cheng, Ningbo; Ding, Gang; Huang, Wenzhe; Wang, Zhenzhong; Xiao, Wei

2016-10-01

Four Astragalus polysaccharides (APS1-APS4) were isolated from the water extract of Radix Astragali and purified through ethanol precipitation with 20 %, 40 %, 60 % and 80 % ethanol, respectively. The total sugar content was measured by sulfuric acid-phenol method. Their molecular weight was determined using high performance gel permeation chromatography (HPGPC) and their monosaccharide composition was analyzed by reversed-phase high performance liquid chromatography (HPLC) after pre-column derivatization. Then the immunobiologic activity of APS was evaluated by the experiment of spleen lymphocytes proliferation in vitro. The data suggested that precipitation by different concentration of ethanol will obtain different molecular weight APS, the higher concentration of ethanol the smaller molecular weight for APS. The molecular weights of four APS were 257.7 kDa, 40.1 kDa, 15.3 kDa and 3.2 kDa. Monosaccharide composition analysis indicated that APS1 consisted of glucose only, and APS2 all consisted of arabinose. APS3 consisted of rhamnose, glucose, galactose and arabinose and APS4 consisted of galactose and arabinose, in a molar ratio of 1:10.76:6.55:12 and 3.02:1. The result of immunobiologic activity assay showed that both APS2 and APS3 can effectively stimulate normal spleen lymphocyte proliferation in vitro. Apart from this, the effect of APS2 also showed dose dependent tendency from 6.25 μg/mL to 800 μg/mL. The result of this research indicated that Astragalus polysaccharides, which consist of arabinose and their molecular weight between 15.2 kDa to 40.1 kDa, neither too high nor too low, had significant immune activity.

Photoinduced optical anisotropy in azobenzene methacrylate block copolymers: Influence of molecular weight and irradiation conditions

DEFF Research Database (Denmark)

Gimeno, Sofia; Forcen, Patricia; Oriol, Luis

2009-01-01

The photoinduced anisotropy in a series of azomethacrylate block copolymers with different Molecular weights and azo contents has been investigated under several irradiation conditions. Depending on molecular weight and composition, different microstructures (disordered, lamellar, spherical) appe...

Development of haplotype-specific molecular markers for the low-molecular-weight glutenin subunits

Science.gov (United States)

Low-molecular-weight glutenin subunits (LMW-GSs) are one of the major components of gluten and their allelic variation has been widely associated with numerous wheat end-use quality parameters. These proteins are encoded by multigene families located at the orthologous Glu-3 loci (Glu-A3, Glu-B3 and...

Clinical implications of the microbiome in urinary tract diseases.

Science.gov (United States)

Hiergeist, Andreas; Gessner, André

2017-03-01

The purpose of this review is to outline and evaluate the most recent literature on the role of the microbiome in urinary tract diseases. High throughput molecular DNA sequencing of bacterial 16S rRNA genes enabled the analysis of complex microbial communities inhabiting the human urinary tract. Several recent studies have identified bacterial taxa of the urinary microbiome to impact urinary tract diseases including interstitial cystitis, urgency urinary incontinence or calcium oxalate stone formation. Furthermore, treatment of urinary tract infections by antibiotics globally impacts community profiles of the intestinal microbiota and might indirectly influence human health. Alternative treatment options like application of probiotics for the treatment of urinary tract infections are currently under investigation. The urinary microbiome and its relationship to urinary tract diseases is currently under comprehensive investigation. Further studies are needed to shed light on the role of commensal microbiota for urinary tract infections.

Molecular weight determination of bisbenzyl-isoquinoline alkaloids by 252Cf-plasma desorption mass spectrometer

International Nuclear Information System (INIS)

Kohno, Hiroyuki; Tatsunami, Shinobu; Hiroi, Tomoko; Kouyama, Hiroshi; Taniguchi, Masashi; Yago, Nagasumi; Nakamura, Iwao

1995-01-01

Bisbenzylisoquinoline alkaloids of Stephania cepharantha have been used for various clinical purposes and recently reevaluated as stimulators of interleukin secretion in tissues. We analyzed molecular stuctures of bisbenzylisoquinoline alkaloids by determining their molecular weights using the 252 Cf-plasma desorption mass spectrometry (PDMS). The spectra were accumulated for 500 000 fission events. The acceleration voltage used here was 15 kV. Samples were analyzed using nitrocellulose-coated sample targets. Of the 5 alkaloids studied here, cepharanthine gave a main peak of molecular weight of 606.1 for the theoretical molecular weight of 606.7. The other minor peaks were considered to be demethylated fragment ions. 252 Cf-PDMS should be quite useful in studying structure, metabolism and pharmacokinetics of various drugs with extremely low coefficients of variation. (author)

High molecular weight poly(L-lactide) and poly(ethylene oxide) blends : Thermal characterization and physical properties

NARCIS (Netherlands)

Nijenhuis, AJ; Colstee, E; Grijpma, DW; Pennings, AJ

1996-01-01

The miscibility of high molecular weight poly(L-lactide) (PLLA) with high molecular weight poly(ethylene oxide) (PEG) was studied by differential scanning calorimetry. Ail blends containing up to 50 weight% PEO showed single glass transition temperatures. The PLLA and PEO melting temperatures were

Nasal Delivery of High Molecular Weight Drugs

Directory of Open Access Journals (Sweden)

Erdal Cevher

2009-09-01

Full Text Available Nasal drug delivery may be used for either local or systemic effects. Low molecular weight drugs with are rapidly absorbed through nasal mucosa. The main reasons for this are the high permeability, fairly wide absorption area, porous and thin endothelial basement membrane of the nasal epithelium. Despite the many advantages of the nasal route, limitations such as the high molecular weight (HMW of drugs may impede drug absorption through the nasal mucosa. Recent studies have focused particularly on the nasal application of HMW therapeutic agents such as peptide-protein drugs and vaccines intended for systemic effects. Due to their hydrophilic structure, the nasal bioavailability of peptide and protein drugs is normally less than 1%. Besides their weak mucosal membrane permeability and enzymatic degradation in nasal mucosa, these drugs are rapidly cleared from the nasal cavity after administration because of mucociliary clearance. There are many approaches for increasing the residence time of drug formulations in the nasal cavity resulting in enhanced drug absorption. In this review article, nasal route and transport mechanisms across the nasal mucosa will be briefly presented. In the second part, current studies regarding the nasal application of macromolecular drugs and vaccines with nanoand micro-particulate carrier systems will be summarised.

Low Molecular Weight Z-Tetraol Boundary Lubricant Films in Hard Disk Drives

Directory of Open Access Journals (Sweden)

R. J. Waltman

2012-01-01

Full Text Available Lower molecular weight Z-Tetraol films exhibit increased mechanical spacing in the slider-disk interface due to a lower z-profile. An increased resistance to lubricant disturbance on the disk surface (e.g., lube moguls with decreasing film thickness is attributed to an increasing contribution from the polar component of the disjoining pressure. Evaporative loss at temperatures typically encountered in a hard-disk drive also increases with decreasing molecular weight but is strongly dependent on the initial bonded fraction.

Pulsed NMR studies of crosslinking and entanglements in high molecular weight linear polydimethylsiloxanes

International Nuclear Information System (INIS)

Folland, R.; Charlesby, A.

1977-01-01

Pulsed NMR studies of proton spin relaxation are used to investigate both radiation-induced cross linking and entanglements in three high molecular weight linear polydimethylsiloxanes (Msub(w) = 26,000, 63,000 and 110,000). Particular emphasis is placed on the spin-spin relaxation since this is determined by the slower relative translational motions of the polymer chains and hence profoundly affected by the presence of intermolecular couplings such as crosslinks or entanglements. The spin-lattice relaxation times, T 1 , are determined by the fast anisotropic chain rotations and are rather insensitive to such intermolecular couplings. The spin-spin relaxation in these materials is represented by a double exponential decay involving two time constants, Tsub(2S) and Tsub(2L). The shorter component, Tsub(2S), is attributed to network material, which may be either of a dynamic form arising from temporary entanglements or of a permanent nature due to crosslinks. The concentration of entanglements depends on the initial molecular weight of the sample whereas the concentration of crosslinks is a function of the radiation dose. The longer component, Tsub(2L), is attributed to the non-network molecules. On the time scale of the NMR measurements the entanglements are shown to act in the same way as crosslinks. The variation of the relative proportions of network and non-network material with dose is shown to be accounted for by using standard gelation theory when allowance is made for the initial effective crosslink density due to entanglements. The analysis provides a value for the average molecular weight per entanglement point of 27,000 +- 1000 which is consistent with the critical molecular weight for entanglements of 29,000. The dependences of Tsub(2S) and Tsub(2L) on dose and molecular weight are also discussed in terms of the molecular motion. (author)

Hofmeister effect on thermo-responsive poly(propylene oxide): Role of polymer molecular weight and concentration

DEFF Research Database (Denmark)

Moghaddam, Saeed Zajforoushan; Thormann, Esben

2016-01-01

) salts on aqueous solutions of poly(propylene oxide) (PPO) is studied. Four different molecular weights of PPO were investigated, to determine how the variation in the polymer coil size affects the Hofmeister effect. The investigation was further conducted for different PPO concentrations, in order...... with the transition. It was observed that increasing the molecular weight weakens the effect of the both salts, which is interpreted in terms of a scaling law between the molecular weight and the accessible surface area of the polymers. Increasing the PPO concentration further diminished the NaCl effect...

Purification and partial characterization of low molecular weight vicilin-like glycoprotein from the seeds of Citrullus lanatus.

Science.gov (United States)

Yadav, Sushila; Tomar, Anil Kumar; Jithesh, O; Khan, Meraj Alam; Yadav, R N; Srinivasan, A; Singh, Tej P; Yadav, Savita

2011-12-01

The watermelon (Citrullus lanatus) seeds are highly nutritive and contain large amount of proteins and many beneficial minerals such as magnesium, calcium, potassium, iron, phosphorous, zinc etc. In various parts of the world, C. lanatus seed extracts are used to cure cancer, cardiovascular diseases, hypertension, and blood pressure. C. lanatus seed extracts are also used as home remedy for edema and urinary tract problems. In this study, we isolated protein fraction of C. lanatus seeds using various protein separation methods. We successfully purified a low molecular weight vicilin-like glycoprotein using chromatographic methods followed by SDS-PAGE and MALDI-TOF/MS identification. This is the first report of purification of a vicilin like polypeptide from C. lanatus seeds. In next step, we extracted mRNA from immature seeds and reverse transcribed it using suitable forward and reverse primers for purified glycoprotein. The PCR product was analysed on 1% agarose gel and was subsequently sequenced by Dideoxy DNA sequencing method. An amino acid translation of the gene is in agreement with amino acid sequences of the identified peptides.

Low molecular-weight phenols in Tannat wines made by alternative winemaking procedures.

Science.gov (United States)

Favre, Guzmán; Peña-Neira, Álvaro; Baldi, Cecilia; Hernández, Natalia; Traverso, Sofía; Gil, Graciela; González-Neves, Gustavo

2014-09-01

Low molecular weight phenols of Tannat red wines produced by Traditional Maceration (TM), Prefermentative Cold Maceration (PCM), Maceration Enzyme (ENZ) and grape-Seed Tannins additions (ST), were performed and discussed. Alternatives to TM increased wine phenolic contents but unequally, ST increased mainly smaller flavans-3-ol, PCM anthocyanins and ENZ proanthocyanidins (up to 2250 mg/L). However low molecular weight flavan-3-ols remained below 9 mg/L in all wines, showing that there is not necessarily a correspondence between wine richness in total tannins and flavan-3-ols contents at low molecular weight. PCM wines had particularly high concentrations of tyrosol and tryptophol, yeast metabolism derived compounds. The use of grape-seed enological tannins did not increase grape seed derived phenolic compounds such as gallic acid. Caftaric acid was found in concentrations much higher than those reported in other grape varieties. Wine phenolic content and composition was considerably affected by the winemaking procedures tested. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of polymer additive molecular weight on surface and ...

Indian Academy of Sciences (India)

2, April 2011, pp. 347–356. c Indian Academy of Sciences. Influence of polymer additive molecular weight on surface and microstructural characteristics of electrodeposited copper. R MANU. ∗ and SOBHA JAYAKRISHNAN. Electroplating and Metal Finishing Technology Division, Central Electrochemical Research Institute,.

Urinary collagen fragments are significantly altered in diabetes: a link to pathophysiology.

Directory of Open Access Journals (Sweden)

David M Maahs

2010-09-01

Full Text Available The pathogenesis of diabetes mellitus (DM is variable, comprising different inflammatory and immune responses. Proteome analysis holds the promise of delivering insight into the pathophysiological changes associated with diabetes. Recently, we identified and validated urinary proteomics biomarkers for diabetes. Based on these initial findings, we aimed to further validate urinary proteomics biomarkers specific for diabetes in general, and particularity associated with either type 1 (T1D or type 2 diabetes (T2D.Therefore, the low-molecular-weight urinary proteome of 902 subjects from 10 different centers, 315 controls and 587 patients with T1D (n = 299 or T2D (n = 288, was analyzed using capillary-electrophoresis mass-spectrometry. The 261 urinary biomarkers (100 were sequenced previously discovered in 205 subjects were validated in an additional 697 subjects to distinguish DM subjects (n = 382 from control subjects (n = 315 with 94% (95% CI: 92-95 accuracy in this study. To identify biomarkers that differentiate T1D from T2D, a subset of normoalbuminuric patients with T1D (n = 68 and T2D (n = 42 was employed, enabling identification of 131 biomarker candidates (40 were sequenced differentially regulated between T1D and T2D. These biomarkers distinguished T1D from T2D in an independent validation set of normoalbuminuric patients (n = 108 with 88% (95% CI: 81-94% accuracy, and in patients with impaired renal function (n = 369 with 85% (95% CI: 81-88% accuracy. Specific collagen fragments were associated with diabetes and type of diabetes indicating changes in collagen turnover and extracellular matrix as one hallmark of the molecular pathophysiology of diabetes. Additional biomarkers including inflammatory processes and pro-thrombotic alterations were observed.These findings, based on the largest proteomic study performed to date on subjects with DM, validate the previously described biomarkers for DM, and pinpoint differences in the urinary

Urinary incontinence surgery - female - discharge

Science.gov (United States)

... activities, such as golfing, playing tennis, bowling, running, biking, weight lifting, gardening or mowing, and vacuuming for ... A.D.A.M. Editorial team. Related MedlinePlus Health Topics Urinary Incontinence Browse the Encyclopedia A.D. ...

High Molecular Weight Polybenzimidazole Membranes for High Temperature PEMFC

DEFF Research Database (Denmark)

Yang, Jingshuai; Cleemann, Lars Nilausen; Steenberg, T.

2014-01-01

High temperature operation of proton exchange membrane fuel cells under ambient pressure has been achieved by using phosphoric acid doped polybenzimidazole (PBI) membranes. To optimize the membrane and fuel cells, high performance polymers were synthesized of molecular weights from 30 to 94 kDa w...

Correlation between human maternal-fetal placental transfer and molecular weight of PCB and dioxin congeners/isomers.

Science.gov (United States)

Mori, Chisato; Nakamura, Noriko; Todaka, Emiko; Fujisaki, Takeyoshi; Matsuno, Yoshiharu; Nakaoka, Hiroko; Hanazato, Masamichi

2014-11-01

Establishing methods for the assessment of fetal exposure to chemicals is important for the prevention or prediction of the child's future disease risk. In the present study, we aimed to determine the influence of molecular weight on the likelihood of chemical transfer from mother to fetus via the placenta. The correlation between molecular weight and placental transfer rates of congeners/isomers of polychlorinated biphenyls (PCBs) and dioxins was examined. Twenty-nine sample sets of maternal blood, umbilical cord, and umbilical cord blood were used to measure PCB concentration, and 41 sample sets were used to analyze dioxins. Placental transfer rates were calculated using the concentrations of PCBs, dioxins, and their congeners/isomers within these sample sets. Transfer rate correlated negatively with molecular weight for PCB congeners, normalized using wet and lipid weights. The transfer rates of PCB or dioxin congeners differed from those of total PCBs or dioxins. The transfer rate for dioxin congeners did not always correlate significantly with molecular weight, perhaps because of the small sample size or other factors. Further improvement of the analytical methods for dioxin congeners is required. The findings of the present study suggested that PCBs, dioxins, or their congeners with lower molecular weights are more likely to be transferred from mother to fetus via the placenta. Consideration of chemical molecular weight and transfer rate could therefore contribute to the assessment of fetal exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Molecular weights distribution and temperature effects in the styrene polymerization initiated with gamma rays

International Nuclear Information System (INIS)

Burillo, G.; Martinez, R.

1979-01-01

The polymerization of styrene irradiated in a 60 CO source to 18 0 C temperature and to 70 0 C temperature was studied, in order to reduce the irradiation time raising the polymerization rate and looking for a highest molecular weight. The radiation doses used were from 0.2 to 33.26 Mrad, at the rate of 56 rad/sec, the percent of polymerization and the molecular weight formed were determined, the results indicate one highest molecular weight of 132,700 when the radiation dose of 20 Mrad and the temperature of 20 0 C were used, and one of 395,000 when the irradiation is carried out to 70 0 C. (author)

In vitro studies of PEG thin films with different molecular weights deposited by MAPLE

DEFF Research Database (Denmark)

Paun, Irina Alexandra; Ion, Valentin; Luculescu, Catalin-Romeo

2012-01-01

and their behavior in vitro. Thus, immersion in PBS induced swelling of the PEG films, which was more pronounced for PEG polymers of higher molecular weight. Prior to immersion in PBS, the PEG films of higher molecular weight were more hydrophilic, the water contact angles decreasing from ∼66 grd for PEG400 to ∼41...

Proton transport properties of poly(aspartic acid) with different average molecular weights

Energy Technology Data Exchange (ETDEWEB)

Nagao, Yuki, E-mail: ynagao@kuchem.kyoto-u.ac.j [Department of Mechanical Systems and Design, Graduate School of Engineering, Tohoku University, 6-6-01 Aoba Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Imai, Yuzuru [Institute of Development, Aging and Cancer (IDAC), Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai 980-8575 (Japan); Matsui, Jun [Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Sendai 980-8577 (Japan); Ogawa, Tomoyuki [Department of Electronic Engineering, Graduate School of Engineering, Tohoku University, 6-6-05 Aoba Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Miyashita, Tokuji [Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Sendai 980-8577 (Japan)

2011-04-15

Research highlights: Seven polymers with different average molecular weights were synthesized. The proton conductivity depended on the number-average degree of polymerization. The difference of the proton conductivities was more than one order of magnitude. The number-average molecular weight contributed to the stability of the polymer. - Abstract: We synthesized seven partially protonated poly(aspartic acids)/sodium polyaspartates (P-Asp) with different average molecular weights to study their proton transport properties. The number-average degree of polymerization (DP) for each P-Asp was 30 (P-Asp30), 115 (P-Asp115), 140 (P-Asp140), 160 (P-Asp160), 185 (P-Asp185), 205 (P-Asp205), and 250 (P-Asp250). The proton conductivity depended on the number-average DP. The maximum and minimum proton conductivities under a relative humidity of 70% and 298 K were 1.7 . 10{sup -3} S cm{sup -1} (P-Asp140) and 4.6 . 10{sup -4} S cm{sup -1} (P-Asp250), respectively. Differential thermogravimetric analysis (TG-DTA) was carried out for each P-Asp. The results were classified into two categories. One exhibited two endothermic peaks between t = (270 and 300) {sup o}C, the other exhibited only one peak. The P-Asp group with two endothermic peaks exhibited high proton conductivity. The high proton conductivity is related to the stability of the polymer. The number-average molecular weight also contributed to the stability of the polymer.

Initial experience of functional imaging of upper urinary tract neoplasm by diffusion-weighted magnetic resonance imaging

International Nuclear Information System (INIS)

Yoshida, Soichiro; Masuda, Hitoshi; Saito, Kazutaka; Kawakami, Satoru; Kihara, Kazunori; Ishii, Chikako

2008-01-01

Diffusion-weighted (DW) magnetic resonance imaging (MRI) provides functional information widely used in the diagnosis of acute cerebral stroke. We reported our initial experience of this imaging technique of upper urinary tract (UUT) urothelial carcinoma (UC). Diffusion-weighted magnetic resonance imaging was carried out in 10 consecutive patients with suspected UUT UC. With conventional imaging, seven were diagnosed as having renal pelvic tumors and two were highly suspected of having UUT UC. These nine patients were diagnosed histopathologically as having renal pelvic UC by subsequent operation. The last patient was confirmed as experiencing benign stenosis. DW MRI was obtained with a 1.5-T MR imager without a breath-holding sequence. The apparent diffusion coefficient (ADC) values of renal parenchyma, dilated collecting system, and tumor were calculated. The differences were analyzed using Wilcoxon t-test. On DW MRI, all nine tumors showed hyperintensity with negligible urinary intensity. Two cases of highly suspected UUT UC with unclear conventional MRI had high signal intensity and contrast. The case of benign stenosis had negative DW MRI. The median (range) ADC value of the tumor (0.803 [0.412-0.958] x 10 -3 mm 2 /s) was significantly lower than those of the dilated collecting system (2.19 [1.42-2.40] x 10 -3 ) and renal parenchyma (1.28 [0.922-1.45] x 10 -3 , respectively (P<0.01 and P<0.01). This is the first report on the application of DW MRI for a series of UUT UC. With this technique, a clear demonstration of UUT UC could be obtained. Moreover, this imaging technique is potentially useful to identify small lesions if they have a low diffusion coefficient. (author)

Effect of molecular weight on the vibronic structure of a diketopyrrolopyrrole polymer

KAUST Repository

Hayes, Sophia C.

2016-09-27

Resonance Raman Spectroscopy (RRS) is employed in this study to examine the influence of molecular weight on the optical response of a diketopyrrolopyrrole polymer (DPP-TT-T) in solution. The vibronic structure observed for the ground state absorption of this polymer is found to vary with molecular weight and solvent. Resonance Raman Intensity Analysis (RRIA) revealed that the absorption spectra can be described by at least two dipole-allowed transitions and the vibronic structure variation is due to differing contributions from linear and curved segments of the polymer.

Effect of molecular weight on the vibronic structure of a diketopyrrolopyrrole polymer

KAUST Repository

Hayes, Sophia C.; Pieridou, Galatia; Vezie, Michelle; Few, Sheridan; Bronstein, Hugo; Meager, Iain; McCulloch, Iain; Nelson, Jenny

2016-01-01

Resonance Raman Spectroscopy (RRS) is employed in this study to examine the influence of molecular weight on the optical response of a diketopyrrolopyrrole polymer (DPP-TT-T) in solution. The vibronic structure observed for the ground state absorption of this polymer is found to vary with molecular weight and solvent. Resonance Raman Intensity Analysis (RRIA) revealed that the absorption spectra can be described by at least two dipole-allowed transitions and the vibronic structure variation is due to differing contributions from linear and curved segments of the polymer.

The influence of molecular weight in radiotracers of inflamators processes

International Nuclear Information System (INIS)

Mesa Duennas, N.; Zayas Crespo, F.; Piedra Mazorra, J.; Diaz Barreto, M; Rodriguez Alfonso, M.E.; Perez Fuentes, A.

2004-01-01

Four 99mTc-radiopharmaceuticals (RPs) were compared as a radiotracers of inflammatory process. The RPs were divided in two groups according to their molecular weights and nature. One group included the human IgG and the ior t3 MoAb (anti-CD3), another included the Ciprofloxacine and the DMSA. The RPs were studied by different quality controls, and a biodistribution study in an aseptic inflammatory model made by steril Carragenin. The results obtained in the reduction of the immunoglobulins with 2-mercaptoethanol and sodium metabisulphite demonstrated that both reducing agents were equivalent, because the radiochemical purity obtained were similar and independent of the immunoglobulins. The biodistribution demonstrated a higher incorporation for the radiopharmaceuticals of high molecular weight, and the highest values were obtained with the 2-mercaptoethanol

Hydrodynamic characterization and molecular weight estimation of ultrasonically sheared DNA; Caracterizacion hidrodinamica y estimacion de pesos moleculares de DNA degradado por ultrasonidos

Energy Technology Data Exchange (ETDEWEB)

Casal, J I; Garces, F; Garcia-Sacristan, A

1981-07-01

The sedimentation coefficients and intrinsic viscosities of ultrasonically sheared calf thymus DNA have been determined. The molecular weight estimation according to this parameters have been compared with the ones obtained from the electrophoretic migration rates based on the calibration proposed using the known molecular weight restriction fragments of X-ENA. (Author) 35 refs.

Application of radiation grafting techniques to prepare the high molecular weight water-soluble polymer

International Nuclear Information System (INIS)

Le Hai; Nguyen Quoc Hien; Nguyen Tan Man; Truong Thi Hanh; Le Huu Tu; Tran Thi Tam; Pham Thi Sam; Pham Anh Tuan; Le Dinh Lang

2003-01-01

The results of the study on the preparation of the high molecular weight water-soluble polymers by radiation grafting and their properties is presented as follows: 1/ by radiation grafting, the molecular weight of PVA was increased 20 times and PAM was increased only 3 times; 2/ the thermal and medium stability of poly(vinyl alcohol) grafted with acrylamide was obviously improved. (LH)

Comparison of computed tomographic urography, magnetic resonance urography and the combination of diffusion weighted imaging in diagnosis of upper urinary tract cancer

Energy Technology Data Exchange (ETDEWEB)

Wu, Guang-yu; Lu, Qing; Wu, Lian-ming [Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China); Zhang, Jin [Department of Urinary Surgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China); Chen, Xiao-xi [Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China); Xu, Jian-rong, E-mail: renjixujr@163.com [Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China)

2014-06-15

Purpose: To evaluate the performance of computed tomographic urography (CTU), static-fluid magnetic resonance urography (static-fluid MRU) and combinations of CTU, static-fluid MRU and diffusion weighted imaging (DWI) in the diagnosis of upper urinary tract cancer. Material and Methods: Between January 2010 and June 2011, patients with suspected UUT cancer underwent CTU, static-fluid MRU and DWI (b = 1000 s/mm{sup 2}) within a 1-week period. The diagnostic performances of CTU, static-fluid MRU and combinations of CTU, static-fluid MRU and DWI for upper urinary tract cancer were prospectively evaluated. The ureteroscopic and histopathologic findings were compared with the imaging findings. Results: Compared to static-fluid MRU alone (sensitivity: 76/75%, reader 1/reader 2), combining DWI with MRI can increase the sensitivity (sensitivity: 84/84%, p = 0.031/p = 0.016) of upper urinary tract cancer diagnosis. CTU had greater sensitivity (95/94%) and accuracy (92/91%) than both static-fluid MRU (sensitivity: p < 0.001/p < 0.001 and accuracy: 83/81%, p = 0.001/p < 0.001) and static-fluid MRU with DWI (sensitivity: p = 0.023/p = 0.039 and accuracy: 87/85%, p = 0.042/p = 0.049) for the diagnosis of upper urinary tract cancers. Compared with CTU alone, CTU with DWI did not significantly increase sensitivity, specificity or accuracy. However, the diagnostic confidence was improved when the combined technique was used (p = 0.031/p = 0.024). Moreover, there was no significant change in sensitivity, specificity, accuracy or diagnostic confidence when static-fluid MRU was used in combination with CTU and DWI. Conclusion: Although there is a potential role for static-fluid MRU and static-fluid MRU with DWI in urinary tract imaging, CTU is still the better choice for the diagnosis of upper urinary tract cancer. Combining DWI with CTU can help improve confidence in upper urinary tract cancer diagnoses.

Loss of high-molecular-weight cytokeratin antigenicity in prostate tissue obtained by transurethral resections

DEFF Research Database (Denmark)

Multhaupt, H A; Fessler, J N; Warhol, M J

2000-01-01

could be restored in these specimens by antigen retrieval in a low pH citrate buffer using a microwave heat technique. Keratin staining in needle biopsies and total prostatectomies was unaffected. CONCLUSION: In summary, our results indicate the technique of transurethral resection results in a specific......OBJECTIVE: Staining of prostatic basal cells for the expression of high-molecular-weight cytokeratin has been suggested as a way of distinguishing benign from malignant prostate glands. We evaluated the utility of high-molecular-weight cytokeratin in the diagnosis of malignancy in prostate...... specimens obtained in various ways. DESIGN: Prostate tissues obtained from needle biopsies, transurethral resections, and total prostatectomies were immunostained with monoclonal antibody 34betaE12, an antibody directed against high-molecular-weight cytokeratins. RESULTS: Antiserum to high...

Molecular lipid species in urinary exosomes as potential prostate cancer biomarkers.

Science.gov (United States)

Skotland, Tore; Ekroos, Kim; Kauhanen, Dimple; Simolin, Helena; Seierstad, Therese; Berge, Viktor; Sandvig, Kirsten; Llorente, Alicia

2017-01-01

Exosomes have recently appeared as a novel source of noninvasive cancer biomarkers, since these nanovesicles contain molecules from cancer cells and can be detected in biofluids. We have here investigated the potential use of lipids in urinary exosomes as prostate cancer biomarkers. A high-throughput mass spectrometry quantitative lipidomic analysis was performed to reveal the lipid composition of urinary exosomes in prostate cancer patients and healthy controls. Control samples were first analysed to characterise the lipidome of urinary exosomes and test the reproducibility of the method. In total, 107 lipid species were quantified in urinary exosomes. Several differences, for example, in cholesterol and phosphatidylcholine, were found between urinary exosomes and exosomes derived from cell lines, thus showing the importance of in vivo studies for biomarker analysis. The 36 most abundant lipid species in urinary exosomes were then quantified in 15 prostate cancer patients and 13 healthy controls. Interestingly, the levels of nine lipids species were found to be significantly different when the two groups were compared. The highest significance was shown for phosphatidylserine (PS) 18:1/18:1 and lactosylceramide (d18:1/16:0), the latter also showed the highest patient-to-control ratio. Furthermore, combinations of these lipid species and PS 18:0-18:2 distinguished the two groups with 93% sensitivity and 100% specificity. Finally, in agreement with the reported dysregulation of sphingolipid metabolism in cancer cells, alteration in specific sphingolipid lipid classes were observed. This study shows for the first time the potential use of exosomal lipid species in urine as prostate cancer biomarkers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cellular Viscosity in Prokaryotes and Thermal Stability of Low Molecular Weight Biomolecules.

Science.gov (United States)

Cuecas, Alba; Cruces, Jorge; Galisteo-López, Juan F; Peng, Xiaojun; Gonzalez, Juan M

2016-08-23

Some low molecular weight biomolecules, i.e., NAD(P)H, are unstable at high temperatures. The use of these biomolecules by thermophilic microorganisms has been scarcely analyzed. Herein, NADH stability has been studied at different temperatures and viscosities. NADH decay increased at increasing temperatures. At increasing viscosities, NADH decay rates decreased. Thus, maintaining relatively high cellular viscosity in cells could result in increased stability of low molecular weight biomolecules (i.e., NADH) at high temperatures, unlike what was previously deduced from studies in diluted water solutions. Cellular viscosity was determined using a fluorescent molecular rotor in various prokaryotes covering the range from 10 to 100°C. Some mesophiles showed the capability of changing cellular viscosity depending on growth temperature. Thermophiles and extreme thermophiles presented a relatively high cellular viscosity, suggesting this strategy as a reasonable mechanism to thrive under these high temperatures. Results substantiate the capability of thermophiles and extreme thermophiles (growth range 50-80°C) to stabilize and use generally considered unstable, universal low molecular weight biomolecules. In addition, this study represents a first report, to our knowledge, on cellular viscosity measurements in prokaryotes and it shows the dependency of prokaryotic cellular viscosity on species and growth temperature. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Clinical effects of low-molecular-weight heparin combined with ...

African Journals Online (AJOL)

Purpose: To explore the clinical effects of low-molecular-weight heparin (LMWH) combined with ulinastatin (UTI) in children with acute pancreatitis. Methods: In total, 560 patients with severe acute pancreatitis treated at Binzhou People's Hospital, Shandong, China, from April 2012 to June 2014 were enrolled in this study.

Molecular imprinted polymer-coated optical fiber sensor for the identification of low molecular weight molecules.

Science.gov (United States)

Lépinay, Sandrine; Ianoul, Anatoli; Albert, Jacques

2014-10-01

A biomimetic optical probe for detecting low molecular weight molecules (maltol, 3-hydroxy-2-methyl-4H-pyran-4-one, molecular weight of 126.11 g/mol), was designed, fabricated, and characterized. The sensor couples a molecular imprinted polymer (MIP) and the Bragg grating refractometry technology into an optical fiber. The probe is fabricated first by inscribing tilted grating planes in the core of the fiber, and then by photopolymerization to immobilize a maltol imprinted MIP on the fiber cladding surface over the Bragg grating. The sensor response to the presence of maltol in different media is obtained by spectral interrogation of the fiber transmission signal. The results showed that the limit of detection of the sensor reached 1 ng/mL in pure water with a sensitivity of 6.3 × 10(8)pm/M. The selectivity of the sensor against other compounds and its reusability were also studied experimentally. Finally, the unambiguous detection of concentrations as little as 10nM of maltol in complex media (real food samples) by the MIP-coated tilted fiber Bragg grating sensor was demonstrated. Copyright © 2014 Elsevier B.V. All rights reserved.

Radiation chemistry of polymer degradation processes: molecular weight distribution effects

International Nuclear Information System (INIS)

Viswanathan, N.S.

1976-01-01

The molecular weight distributions of poly(methyl methacrylate) irradiated at 15 and 25 MeV with electron beams were investigated. The experimental values for the effect of chain scissions on the dispersivity agreed well with theoretical predictions

Urinary polycyclic aromatic hydrocarbon metabolites among 3-year-old children from Krakow, Poland.

Science.gov (United States)

Sochacka-Tatara, Elżbieta; Majewska, Renata; Perera, Frederica P; Camann, David; Spengler, John; Wheelock, Kylie; Sowa, Agata; Jacek, Ryszard; Mróz, Elżbieta; Pac, Agnieszka

2018-07-01

Polycyclic aromatic hydrocarbons (PAHs) are widespread in the environment and can adversely affect human health. The aim of the present study is to describe the level of PAHs exposure in children living in Kraków, one of the most polluted cities in Poland, and to determine the relationship of urinary biomarkers with environmental PAHsexposure. Urinary monohydroxy metabolites (OH-PAHs) of 20 PAHs were assessed in 218 three-year old children, of which only 10 were present in nearly all the samples: monohydroxy metabolites of naphthalene, fluorene, phenantrene and pyrene. Of the metabolites analyzed, hydroxynaphthalenes were predominant and constituted almost 73% of total excreted OH-PAHs, while 1-OH-PYRene was the least abundant (2.3% of total OH-PAHs). All measured urinary OH-PAHs were statistically significantly correlated with each other (R = 0.165-0.880) but the highest correlation coefficients with other individual OH-PAHs and with total OH-PAHs were observed for 2-OH-FLUOR. Children exposed at home to environmental tobacco smoke (ETS) had higher concentrations of fluorene and pyrene urinary metabolites compared to those without ETS exposure; and those exposed to gas-based appliances used for cooking or heating water had higher levels of fluorene and phenanthrene metabolites than children not exposed. The use of coal, wood or oil for heating was associated with elevated levels of 1-OH-PYRene. Urinary PAHs metabolites only modestly reflect high molecular weight carcinogenic PAHs exposures such as those monitored in air in the present study. None of the measured PAHs metabolites was correlated with airborne PM 2.5 and only two were slightly correlated with measured higher molecular mass airborne PAHs. The average concentrations of these specific metabolites in Polish children were much higher than observed in other pediatric populations living in developed countries. Our findings suggest that to capture various sources of PAHs, in addition to 1-OH

Radiodegradation process in PVDF with different molecular weight

International Nuclear Information System (INIS)

Silva, L.; Batista, A.S.M.; Nascimento, J.P.; Furtado, C.A.; Faria, L.O.

2017-01-01

Poly(vinylidene fluoride) (PVDF) is a semi-crystalline polymer with several industrial applications due to its mechanical, ferroelectric and biocompatibility properties. Due to the particularity of some of its applications this polymer is exposed to high energy radiation, for example in the aerospace industry and with biomaterial, in sterilization processes. In this sense it is of interest studies that evaluate the radiodegradation of this material, as a way to predict its mechanical behavior after processes of exposure to gamma radiation. In this study the radioresistance of PVDF with different molecular weights is evaluated, considering that large molecular chains can provide greater resistance than smaller chains. Method: PVDF samples with different molecular weights were produced by the solvent dilution process. They were irradiated with gamma doses of 100, 300, 500, 1000 and 2000 kGy with a source of cobalt in the Laboratório de Irradiação Gama (LIG) of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN). FTIR, UV-Vis, DSC and XRD analyzes were used to evaluate the induced radiodegradation processes immediately after irradiation and one month later. Results: The FTIR and UV-Vis analyzes showed formation of unsaturations in the polymer chains. The DSC technique showed a drop in the crystalline fraction of the polymer confirmed by the XRD technique. Conclusion: Post-irradiation sample evaluations are discussed in terms of the effect of high energy ionizing radiation on polymeric mate-rials for industrial and biomedical use for safety in quality assurance and performance in service. (author)

Radiodegradation process in PVDF with different molecular weight

Energy Technology Data Exchange (ETDEWEB)

Silva, L.; Batista, A.S.M., E-mail: adriananuclear@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Nascimento, J.P.; Furtado, C.A.; Faria, L.O. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-07-01

Poly(vinylidene fluoride) (PVDF) is a semi-crystalline polymer with several industrial applications due to its mechanical, ferroelectric and biocompatibility properties. Due to the particularity of some of its applications this polymer is exposed to high energy radiation, for example in the aerospace industry and with biomaterial, in sterilization processes. In this sense it is of interest studies that evaluate the radiodegradation of this material, as a way to predict its mechanical behavior after processes of exposure to gamma radiation. In this study the radioresistance of PVDF with different molecular weights is evaluated, considering that large molecular chains can provide greater resistance than smaller chains. Method: PVDF samples with different molecular weights were produced by the solvent dilution process. They were irradiated with gamma doses of 100, 300, 500, 1000 and 2000 kGy with a source of cobalt in the Laboratório de Irradiação Gama (LIG) of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN). FTIR, UV-Vis, DSC and XRD analyzes were used to evaluate the induced radiodegradation processes immediately after irradiation and one month later. Results: The FTIR and UV-Vis analyzes showed formation of unsaturations in the polymer chains. The DSC technique showed a drop in the crystalline fraction of the polymer confirmed by the XRD technique. Conclusion: Post-irradiation sample evaluations are discussed in terms of the effect of high energy ionizing radiation on polymeric mate-rials for industrial and biomedical use for safety in quality assurance and performance in service. (author)

Low-molecular-weight poly-carboxylate as crystal growth modifier in ...

Indian Academy of Sciences (India)

Biomineralization; growth modifier; amino acid; low-molecular-weight chiral poly- carboxylate; calcium ... They are also used as gravity sensors, for metal storage and .... The pH of the solutions was maintained at ~10⋅0 for different periods of ...

Practical γ-Ray Level for Low Molecular Weight Chitosan

International Nuclear Information System (INIS)

Yoksan, Rangrong; Chirachanchai, Suwabun; Biramontri, Siriratana

2003-06-01

The present work proposes a practical level of γ-Ray to lower the molecular weigh of chitosan irradiated in solid state and water. The molecular weight reduction is up to 80% at γ-ray amount of 50 kGy. The same level of reduction can be achieved by only 20 kGy in the presence of initiator (K 2 S 2 O 8 or H 2 O 2 ). The structure is significantly changed in the case of chitosan-acetic acid solution or chitosan dispersed in water with 2% aq. K 2 S 2 O 8 solution

Hypoglycemic effect of polysaccharides with different molecular weight of Pseudostellaria heterophylla

Science.gov (United States)

2013-01-01

Abstracts Background The aims of this study were to evaluate the antidiabetic activity and to detect molecular size of Pseudostellaria heterophylla polysaccharide (PHP). Pseudostellaria heterophylla is a medicine extensively used in traditional Chinese medicine formulas to treat diabetes and its complications. Methods Molecular weight of PHP was determined by gel permeation chromatography combined with phenol-sulphuric acid method and the monosaccharides composition was determined by HPLC with a precolumn derivatization. Four polysaccharides with different molecular weight were compared for hypoglycemic active on two animal models both high does alloxan induced type1 diabetic mellitus (T1DM) and high-fat/lower does streptozotocin induced type2 diabetic mellitus (T2DM). Blood sugar, glucose tolerance, and insulin tolerance were detected. Rat serum IL-1β, IL-2, IL-10, Leptin, TNF-α, Acrp30 and CRP were also analyzed by sandwich-ELISA approaches to preliminary probe the hypoglycemic mechanism of PHP. Results The hypoglycemic effects related to molecular size of polysaccharide were more effective against T2DM than T1DM. PHP comprise four monosaccharides of galacturonic acid, glucose, galactose and arabinos. T2DM rats daily receiving oral dose of polysaccharide(100 ~ 400 mg/kg) with 50 ~ 210 kDa molecular weight (PF40) could not only significantly lower blood sugar but also reduce total triglyceride level in serum. PF40 improves in insulin tolerance inhibited the expression of some biomarkers including inflammatory cytokine TNF-α and elevated anti-inflammatory cytokine IL-10, regulated adiponectin Acrp30 and leptin. Conclusions PF40 prevent the cascade of inflammatory events in the treatment of T2DM to block overweight progresses to obesity. PMID:24131482

Nitrogen mineralization in a simulated rhizosphere as influenced by low molecular weight organic substances

OpenAIRE

Begum, Shamim Ara; Kader, MD Abdul; Sleutel, Steven; De Neve, Stefaan

2012-01-01

Rhizodeposits consist of over 200 organic compounds, mainly low-molecular-weight organic substances (LMWOS) such as amino acids (AA), carbohydrates (CH) and carboxylic acids (CA), lipids and phenols. Those LMWOS influence nutrient turnover, particularly N turnover. However, the exact influence of these organic substances on nitrogen mineralization is yet unknown. Therefore, the stimulatory effects of low molecular weight organic substances on nitrogen mineralization in the rhizosphere of a si...

Peptidylation for the determination of low-molecular-weight compounds by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Science.gov (United States)

Tang, Feng; Cen, Si-Ying; He, Huan; Liu, Yi; Yuan, Bi-Feng; Feng, Yu-Qi

2016-05-23

Determination of low-molecular-weight compounds by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has been a great challenge in the analytical research field. Here we developed a universal peptide-based derivatization (peptidylation) strategy for the sensitive analysis of low-molecular-weight compounds by MALDI-TOF-MS. Upon peptidylation, the molecular weights of target analytes increase, thus avoiding serious matrix ion interference in the low-molecular-weight region in MALDI-TOF-MS. Since peptides typically exhibit good signal response during MALDI-TOF-MS analysis, peptidylation endows high detection sensitivities of low-molecular-weight analytes. As a proof-of-concept, we analyzed low-molecular-weight compounds of aldehydes and thiols by the developed peptidylation strategy. Our results showed that aldehydes and thiols can be readily determined upon peptidylation, thus realizing the sensitive and efficient determination of low-molecular-weight compounds by MALDI-TOF-MS. Moreover, target analytes also can be unambiguously detected in biological samples using the peptidylation strategy. The established peptidylation strategy is a universal strategy and can be extended to the sensitive analysis of various low-molecular-weight compounds by MALDI-TOF-MS, which may be potentially used in areas such as metabolomics.

Use of electroporation for high-molecular-weight DNA-mediated gene transfer.

Science.gov (United States)

Jastreboff, M M; Ito, E; Bertino, J R; Narayanan, R

1987-08-01

Electroporation was used to introduce high-molecular-weight DNA into murine hematopoietic cells and NIH3T3 cells. CCRF-CEM cells were stably transfected with SV2NEO plasmid and the genomic DNA from G-418-resistant clones (greater than 65 kb) was introduced into mouse bone marrow and NIH3T3 cells by electroporation. NEO sequences and expression were detected in the hematopoietic tissues of lethally irradiated mice, with 24% of individual spleen colonies expressing NEO. The frequency of genomic DNA transfer into NIH3T3 cells was 0.25 X 10(-3). Electroporation thus offers a powerful mode of gene transfer not only of cloned genes but also of high-molecular-weight DNA into cells.

Studies on a microbially derived, high molecular weight inhibitor of plasma cholesteryl ester transfer protein

International Nuclear Information System (INIS)

Marschke, C.K.; McGee, J.E.; Melchior, G.W.; Castle, C.K.

1989-01-01

The authors have isolated an organism which accumulates an inhibitor of Cholesteryl Ester Transfer Protein (CETP). Purification of 100,000-fold was achieved by ammonium sulfate precipitation followed by Hydroxyl Apatite, Agarose AO.5, and Mono Q (Pharmacia) chromatographies. The use of 14 C-labelled protein molecular weight standards followed by SDS-PAGE revealed some proteolytic activity. However, inhibition of the proteases did not affect the inhibitor potency. The inhibitor has an estimated molecular weight of 40 Kd and appears to exist as two forms. One form was eluted from a Mono Q column by 100 mM NaCl while the other was not bound. Our evidence indicated that the bound form was progressively denatured, or proteolyzed, during storage of the fermentation beer, to the unbound form. Importantly though this molecular change did not affect either inhibitory activity or the apparent molecular weight

Physical Properties of Low-Molecular Weight Polydimethylsiloxane Fluids

Energy Technology Data Exchange (ETDEWEB)

Roberts, Christine Cardinal [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Graham, Alan [Univ. of Colorado, Denver, CO (United States); Nemer, Martin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Phinney, Leslie M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Garcia, Robert M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Soehnel, Melissa Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stirrup, Emily Kate [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-02-01

Physical property measurements including viscosity, density, thermal conductivity, and heat capacity of low-molecular weight polydimethylsiloxane (PDMS) fluids were measured over a wide temperature range (-50°C to 150°C when possible). Properties of blends of 1 cSt and 20 cSt PDMS fluids were also investigated. Uncertainties in the measurements are cited. These measurements will provide greater fidelity predictions of environmental sensing device behavior in hot and cold environments.

Ultra-Fast RAFT-HDA Click Conjugation: An Efficient Route to High Molecular Weight Block Copolymers.

Science.gov (United States)

Inglis, Andrew J; Stenzel, Martina H; Barner-Kowollik, Christopher

2009-11-02

The use of the reversible addition fragmentation chain transfer-hetero Diels-Alder (RAFT-HDA) click reaction for the modular construction of block copolymers is extended to the generation of high molecular weight materials. Cyclopentadienyl end-functionalized polystyrene (PS-Cp) prepared via both atom transfer radical polymerization (ATRP) and the RAFT process are conjugated to poly(isobornyl acrylate) (PiBoA) (also prepared via RAFT polymerization) to achieve well-defined block copolymers with molecular weights ranging from 34 000 to over 100 000 g · mol(-1) and with small polydispersities (PDI HDA click chemistry can provide access to high molecular weight block copolymers in a simple and straight-forward fashion. Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dietary and inhalation exposure to polycyclic aromatic hydrocarbons and urinary excretion of monohydroxy metabolites – A controlled case study in Beijing, China

International Nuclear Information System (INIS)

Zhang, Yanyan; Ding, Junnan; Shen, Guofeng; Zhong, Junjun; Wang, Chen; Wei, Siye; Chen, Chaoqi; Chen, Yuanchen; Lu, Yan; Shen, Huizhong; Li, Wei; Huang, Ye; Chen, Han; Su, Shu; Lin, Nan; Wang, Xilong; Liu, Wenxin; Tao, Shu

2014-01-01

Daily dietary and inhalation exposures to 16 parent polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 13 monohydroxy metabolites (OHPAHs) were monitored for 12 non-smoking university students in Beijing, China, during a controlled feeding experiment. The relationship between the urinary excretion of OHPAHs and the uptake of PAHs was investigated. The results suggest severe exposure of the subjects to PAHs via both dietary and inhalation pathways. Large increase of most urinary OHPAHs occurred after the ingestion of lamb kabob. Higher concentrations of OHPAHs were observed for female subjects, with the intakes of parent PAHs lower than those by males, likely due to the gender differences in metabolism. It appears that besides 1-PYR, metabolites of PHE could also be used as biomarkers to indicate the short-term dietary exposure to PAHs and urinary 3-BaA may serve as the biomarker for inhalation intake of high molecular weight PAHs. Highlights: • The dependence of urinary OHPAHs on PAH intake was explored. • Consumption of lamb kabob resulted in large increase of most urinary OHPAHs. • Gender differences in PAH metabolism was observed. • Urinary metabolites of PHE and PYR can be used as biomarkers for dietary PAH intake. • Urinary 3-BaA may serve as the indicator for the inhalation exposure to BaP eq . -- Severe exposure to PAHs via dietary and inhalation pathways indicated by the intake of parent PAHs as well as the urinary excretion of OHPAHs, was observed for students in Beijing

Effect of the different chain transfer agents on molecular weight and optical properties of poly(methyl methacrylate)

Science.gov (United States)

Çetinkaya, Onur; Demirci, Gökhan; Mergo, Paweł

2017-08-01

Investigation of molecular weight and optical properties of poly(methyl metacrylate) (PMMA) polymerized in house with different chain transfer agents was studied. Isopropyl alcohol (IPA), n-butyl mercaptan (nBMC) and pentamethyl disilane (PMDS) were used as chain transfer agents. The molecular weight (Mw) of PMMA samples were measured by Ostwald viscometer. Mw of bulk polymer samples were decreased with increase the concentration of chain transfer agents (CTA). Since reactivity of used CTAs is not same, molecular weights of samples which were produced with different type of CTA but same concentration of CTA was varied. Higher concentration of n-BMC showed higher scattering. Transmission of samples could not be correlated with different concentration of CTA. Refractive index of samples was not affected by concentration of CTA nevertheless higher molecular weight of CTA showed higher refractive index.

Urinary incontinence: hospital-based prevalence and risk factors

Directory of Open Access Journals (Sweden)

Marzieh Nojomi

2008-02-01

Full Text Available

• BACKGROUND: This study was carried out to determine the prevalence and risk factors of urinary incontinence in women aged 30 to 70 years, who were attending to a gynecologic hospital.
• METHODS: During 2006, married women (aged 30-70 years attending to a teaching gynecological hospital were assessed during their visits for any gynecologic diseases. We used a questionnaire with interview for collecting data. The potential risk factors were measured; i.e., the demographics, menopausal status, urinary symptoms (frequency, nocturia and urgency, urinary incontinence, (urgency, stress and mixed, body mass index, medical history (type of delivery, parity, gravidity, chronic illnesses, medication use, pelvic surgery and seeking medical care for their problem.
• RESULTS: The mean age was 46.5 (± 8.4 years. The mean parity was 5.1 ± 1.5. 27% of the participants reported urinary incontinence. Out of 111 women with urinary incontinence, 77 (18.7%, CI: 14.7-22.7%, 17 (4.1%, CI: 2.2-5.8% and 17 (4.1%, CI: 2.2-5.8% were classified as having stress, urge and mixed urinary incontinence, respectively. The overall prevalence of urinary incontinence was 18.9% (34 subjects in women aged 30-44 years, 30.9% (46 subjects in those aged 45-54 years and 37.8% (31 subjects in those aged 55 years and older. Out of 117 menopause women, 39 (33.3% were incontinent. On average, women reported 4.4 (± 1.06 diurnal and 0.55 (± 0.66 nocturnal voidings in 24 hours. Diurnal and nocturnal frequencies were different between continent and incontinent women. The high parity, excessive birth weight, pelvic trauma, constipation, chronic illnesses (specially diabetes and gynecologic and other pelvic surgeries were known as risk factors for urinary incontinence.
• CONCLUSIONS: There was a significant association between urinary incontinence and high parity, excessive birth weight, pelvic

• Electrospinning and characterization of polyamide 66 nanofibers with different molecular weights

  Directory of Open Access Journals (Sweden)

  Lilia Muller Guerrini

  2009-06-01

  Full Text Available Polyamide 66 (PA66 nanofibers of different molecular weights were obtained by electrospinning of formic acid solutions. An ionic salt, NaCl, was also added to the solutions to increase the conductivity. PA66 concentrations between 15-17 wt.(%/v and electrical fields between 2.0 and 2.5 kV/cm were the best conditions to produce the smallest nanofibers; however, the addition of NaCl increased the fibers average diameters.The characterization of the fibers was done by scanning electron microscopy (SEM, differential scanning calorimetry (DSC, wide angle X rays diffraction (WAXD and Fourier Transformed Infrared (FTIR. As the molecular weight decreased, the nanofibers average diameters also decreased; however, critical number average and weight average molecular weights were necessary for electrospinning. As the amounts of carboxyl terminal groups (CTG increased, the nanofibers average diameters decreased; however, above CTG's critical values of 8.7 x 10-5 mol.g-1 no electrospinning was possible. The addition of ionic salt increased the electrical conductivity of the solutions and increased the nanofibers' average diameters. By DSC, residual solvent in all the electrospun mats was found; two melting endotherms, one between 248 and 258 °C and the other one between 258 and 267 °C, depending on the sample were also observed. These endotherms were attributed to the melting, re-crystallization and re-melting of the PA66 α-phase. The nanofibers had low % of crystallinity compared to a textile fiber. By WAXS and FTIR, confirmation of the presence of α-phase crystals, of small dimensions and highly imperfect and of a very small amount of β and γ-phases crystals in the nanofibers structure was obtained.

• High molecular weight DNA assembly in vivo for synthetic biology applications.

  Science.gov (United States)

  Juhas, Mario; Ajioka, James W

  2017-05-01

  DNA assembly is the key technology of the emerging interdisciplinary field of synthetic biology. While the assembly of smaller DNA fragments is usually performed in vitro, high molecular weight DNA molecules are assembled in vivo via homologous recombination in the host cell. Escherichia coli, Bacillus subtilis and Saccharomyces cerevisiae are the main hosts used for DNA assembly in vivo. Progress in DNA assembly over the last few years has paved the way for the construction of whole genomes. This review provides an update on recent synthetic biology advances with particular emphasis on high molecular weight DNA assembly in vivo in E. coli, B. subtilis and S. cerevisiae. Special attention is paid to the assembly of whole genomes, such as those of the first synthetic cell, synthetic yeast and minimal genomes.

• Isolation of low-molecular-weight lead-binding protein from human erythrocytes

  International Nuclear Information System (INIS)

  Raghavan, S.R.V.; Gonick, H.C.

  1977-01-01

  In blood, lead is mainly associated with erythrocytes and only a very small amount is found in plasma. Previously it was thought that the lead was bound to the erythrocyte cell membrane but more recently it has been observed that lead is bound primarily to the cell contents, ostensibly hemoglobin. In examining the lead-binding properties of normal human erythrocytes and those of lead-exposed industrial workers, we have found that, whereas lead binds only to hemoglobin in normal erythrocytes, there is also appreciable binding of lead to a low-molecular weight-protein in erythrocytes from lead-exposed workers. The synthesis of this protein may be induced by lead exposure. The 10,000 molecular weight protein may act as a storage site and mechanism for segregating lead in a non-toxic form

• A global survey of low-molecular weight carbohydrates in lentils

  Science.gov (United States)

  Lentils contain a range of low-molecular weight carbohydrates (LMWC); however, those have not been well characterized. The objectives of this study were to (1) determine the concentrations of LMWC in lentils grown in six locations, and (2) identify any genetic and environmental effects on those LMWC...

• Molecular and antimicrobial susceptibility characterization of Globicatella sulfidifaciens isolated from sow's urinary tract infection.

  Science.gov (United States)

  Matajira, Carlos E C; Moreno, Luisa Z; Gomes, Vasco T M; Silva, Ana Paula S; Mesquita, Renan E; Amigo, Cristina R; Christ, Ana Paula G; Sato, Maria Inês Z; Moreno, Andrea M

  2017-12-01

  The Globicatella genus comprises Gram-positive, facultative anaerobic, α-hemolytic and catalase negative cocci morphologically and phenotypically very similar to Streptococcus and Aerococcus genus which can lead to misidentification and underestimation of this pathogen. Globicatella species have already been isolated from human and animals with heart and brain disorders. Their clinical relevance in animals, and its zoonotic potential, remains unknown due to the difficulty in their identification. To present the isolation, phenotypic and molecular characterization of G. sulfidifaciens from urinary tract infection in sows. Urine samples from 140 sows of two swine herds located in São Paulo State (Brazil) yielded the isolation of three presumptive G. sulfidifaciens strains. Identification and species confirmation were done by MALDI-TOF MS and 16S rRNA sequencing. Strains were further characterized by single enzyme amplified fragments length polymorphism (SE-AFLP) and broth microdilution techniques. All three isolates were confirmed as G. sulfidifaciens. The SE-AFLP genotyping resulted in distinct fingerprint patterns for each strain. All isolates presented high MIC values to tetracycline, sulphonamides, aminoglycosides and tylosin tartrate, which present high usage in human and animal medicine. Globicatella sulfidifaciens could be related to sporadic urinary tract infections in swine and appear to present alarming antimicrobial susceptibility profile. It is necessary to differentiate Streptococcus-like microorganisms in routine laboratory diagnostics for the correct identification of underestimated species potentially pathogenic to animals.

• Association of urinary cadmium and myocardial infarction

  International Nuclear Information System (INIS)

  Everett, Charles J.; Frithsen, Ivar L.

  2008-01-01

  We conducted a cross-sectional analysis of individuals 45-79 years old in the National Health and Nutrition Examination Survey III (1988-1994) (NHANES III). Myocardial infarction was determined by electrocardiogram (ECG). Our sample included 4912 participants, which when weighted represented 52,234,055 Americans. We performed adjusted logistic regressions with the Framingham risk score, pack-years of smoking, race-ethnicity, and family history of heart attack, and diabetes as covariates. Urinary cadmium ≥0.88 μg/g creatinine had an odds ratio of 1.86 (95% CI 1.26-2.75) compared to urinary cadmium <0.43 μg/g creatinine. This result supports the hypothesis that cadmium is associated with coronary heart disease. When logistic regressions were done by gender, women, but not men, showed a significant association of urinary cadmium with myocardial infarction. Women with urinary cadmium ≥0.88 μg/g creatinine had an odds ratio of 1.80 (95% CI 1.06-3.04) compared to urinary cadmium <0.43 μg/g creatinine. When the analysis was restricted to never smokers (N=2187) urinary cadmium ≥0.88 μg/g creatinine had an odds ratio of 1.85 (95% CI 1.10-3.14) compared to urinary cadmium <0.43 μg/g creatinine

• The adhesive properties of chlorinated ultra-high molecular weight polyethylene

  NARCIS (Netherlands)

  Menting, H.N.A.M.; Voets, P.E.L.; Lemstra, P.J.

  1995-01-01

  Ultra-high molecular weight polyethylene (UHMW-PE) is well known for its abrasion and chemical resistance. Recently we developed a new application for UHMW-PE as a liner in elastomeric hoses. It was found that the adhesion between UHMW-PE and elastomers such as ethylene-propylene-diene monomer

• Molecular weight-dependent degradation and drug release of surface-eroding poly(ethylene carbonate)

  DEFF Research Database (Denmark)

  Bohr, Adam; Wang, Yingya; Harmankaya, Necati

  2017-01-01

  .7 macrophages) and in vivo (subcutaneous implantation in rats). All investigated samples degraded by means of surface erosion (mass loss, but constant molecular weight), which was accompanied by a predictable, erosion-controlled drug release pattern. Accordingly, the obtained in vitro degradation half......Poly(ethylene carbonate) (PEC) is a unique biomaterial showing significant potential for controlled drug delivery applications. The current study investigated the impact of the molecular weight on the biological performance of drug-loaded PEC films. Following the preparation and thorough...... to control the spatial and temporal on-demand degradation and drug release from the employed delivery system....

• Disassembled DJ-1 high molecular weight complex in cortex mitochondria from Parkinson's disease patients

  Directory of Open Access Journals (Sweden)

  Adler Charles

  2009-07-01

  Full Text Available Abstract Correction to Nural H, He P, Beach T, Sue L, Xia W, Shen Y. Disassembled DJ-1 high molecular weight complex in cortex mitochondria from Parkinson's disease patients Molecular Neurodegeneration 2009, 4:23.

• Controlling silk fibroin microspheres via molecular weight distribution

  International Nuclear Information System (INIS)

  Zeng, Dong-Mei; Pan, Jue-Jing; Wang, Qun; Liu, Xin-Fang; Wang, Hui; Zhang, Ke-Qin

  2015-01-01

  Silk fibroin (SF) microspheres were produced by salting out SF solution via the addition of potassium phosphate buffer solution (K 2 HPO 4 –KH 2 PO 4 ). The morphology, size and polydispersity of SF microspheres were adjusted by changing the molecular weight (MW) distribution and concentration of SF, as well as the ionic strength and pH of the buffer solution. Changing the conditions under which the SF fiber dissolved in the Lithium Boride (LiBr) solution resulted in altering the MW distribution of SF solution. Under optimal salting-out conditions (ionic strength > 0.7 M and pH > 7) and using a smaller and narrower SF MW distribution, SF microspheres with smoother shapes and more uniform sizes were produced. Meanwhile, the size and polydispersity of the microspheres increased when the SF concentration was increased from 0.25 mg/mL to 20 mg/mL. The improved SF microspheres, obtained by altering the distribution of molecular weight, have potential in drug and gene delivery applications. - Highlights: • MW distribution was changed by applying different dissolving methods of SF fiber. • Smaller and narrower MW distribution improves the quality of SF microspheres. • Size and polydispersity of microspheres increase as SF concentration increases. • Improved SF microspheres have potential in drug and gene delivery applications

• Controlling silk fibroin microspheres via molecular weight distribution

  Energy Technology Data Exchange (ETDEWEB)

  Zeng, Dong-Mei; Pan, Jue-Jing; Wang, Qun; Liu, Xin-Fang; Wang, Hui [National Engineering Laboratory for Modern Silk, College for Textile and Clothing Engineering, Soochow University, Suzhou, Jiangsu 215123 (China); Zhang, Ke-Qin, E-mail: kqzhang@suda.edu.cn [National Engineering Laboratory for Modern Silk, College for Textile and Clothing Engineering, Soochow University, Suzhou, Jiangsu 215123 (China); Research Center of Cooperative Innovation for Functional Organic/Polymer Material Micro/Nanofabrication, Soochow University, Suzhou, Jiangsu 215123 (China)

  2015-05-01

  Silk fibroin (SF) microspheres were produced by salting out SF solution via the addition of potassium phosphate buffer solution (K{sub 2}HPO{sub 4}–KH{sub 2}PO{sub 4}). The morphology, size and polydispersity of SF microspheres were adjusted by changing the molecular weight (MW) distribution and concentration of SF, as well as the ionic strength and pH of the buffer solution. Changing the conditions under which the SF fiber dissolved in the Lithium Boride (LiBr) solution resulted in altering the MW distribution of SF solution. Under optimal salting-out conditions (ionic strength > 0.7 M and pH > 7) and using a smaller and narrower SF MW distribution, SF microspheres with smoother shapes and more uniform sizes were produced. Meanwhile, the size and polydispersity of the microspheres increased when the SF concentration was increased from 0.25 mg/mL to 20 mg/mL. The improved SF microspheres, obtained by altering the distribution of molecular weight, have potential in drug and gene delivery applications. - Highlights: • MW distribution was changed by applying different dissolving methods of SF fiber. • Smaller and narrower MW distribution improves the quality of SF microspheres. • Size and polydispersity of microspheres increase as SF concentration increases. • Improved SF microspheres have potential in drug and gene delivery applications.

• Participation of Low Molecular Weight Electron Carriers in Oxidative Protein Folding

  Directory of Open Access Journals (Sweden)

  József Mandl

  2009-03-01

  Full Text Available Oxidative protein folding is mediated by a proteinaceous electron relay system, in which the concerted action of protein disulfide isomerase and Ero1 delivers the electrons from thiol groups to the final acceptor. Oxygen appears to be the final oxidant in aerobic living organisms, although the existence of alternative electron acceptors, e.g. fumarate or nitrate, cannot be excluded. Whilst the protein components of the system are well-known, less attention has been turned to the role of low molecular weight electron carriers in the process. The function of ascorbate, tocopherol and vitamin K has been raised recently. In vitro and in vivo evidence suggests that these redox-active compounds can contribute to the functioning of oxidative folding. This review focuses on the participation of small molecular weight redox compounds in oxidative protein folding.

• Electrophoretic behavior in filter paper and molecular weight of insulin

  NARCIS (Netherlands)

  Sluyterman, L.A.A.E.

  1955-01-01

  Insulin travels as well defined band in electropherograms if acetic acid-water 1:2 (v/v) is used as a buffer. Preparations of partially acetylated insulin were analysed by this method. From the results it could be derived that the molecular weight of insulin is 6,000. An improvement in the

High molecular weight polysaccharide that binds and inhibits virus

Science.gov (United States)

Konowalchuk, Thomas W

2014-01-14

This invention provides a high molecular weight polysaccharide capable of binding to and inhibiting virus and related pharmaceutical formulations and methods on inhibiting viral infectivity and/or pathogenicity, as well as immunogenic compositions. The invention further methods of inhibiting the growth of cancer cells and of ameliorating a symptom of aging. Additionally, the invention provides methods of detecting and/or quantifying and/or isolating viruses.

High molecular weight polysaccharide that binds and inhibits virus

Energy Technology Data Exchange (ETDEWEB)

Konowalchuk, Thomas W.; Konowalchuk, Jack

2017-07-18

This invention provides a high molecular weight polysaccharide capable of binding to and inhibiting virus and related pharmaceutical formulations and methods of inhibiting viral infectivity and/or pathogenicity, as well as immunogenic compositions. The invention further includes methods of inhibiting the growth of cancer cells and of ameliorating a symptom of aging. Additionally, the invention provides methods of detecting and/or quantifying and/or isolating viruses.

Development of gel-filter method for high enrichment of low-molecular weight proteins from serum.

Directory of Open Access Journals (Sweden)

Lingsheng Chen

Full Text Available The human serum proteome has been extensively screened for biomarkers. However, the large dynamic range of protein concentrations in serum and the presence of highly abundant and large molecular weight proteins, make identification and detection changes in the amount of low-molecular weight proteins (LMW, molecular weight ≤ 30kDa difficult. Here, we developed a gel-filter method including four layers of different concentration of tricine SDS-PAGE-based gels to block high-molecular weight proteins and enrich LMW proteins. By utilizing this method, we identified 1,576 proteins (n = 2 from 10 μL serum. Among them, 559 (n = 2 proteins belonged to LMW proteins. Furthermore, this gel-filter method could identify 67.4% and 39.8% more LMW proteins than that in representative methods of glycine SDS-PAGE and optimized-DS, respectively. By utilizing SILAC-AQUA approach with labeled recombinant protein as internal standard, the recovery rate for GST spiked in serum during the treatment of gel-filter, optimized-DS, and ProteoMiner was 33.1 ± 0.01%, 18.7 ± 0.01% and 9.6 ± 0.03%, respectively. These results demonstrate that the gel-filter method offers a rapid, highly reproducible and efficient approach for screening biomarkers from serum through proteomic analyses.

The polysaccharide and low molecular weight components of Opuntia ficus indica cladodes: Structure and skin repairing properties.

Science.gov (United States)

Di Lorenzo, Flaviana; Silipo, Alba; Molinaro, Antonio; Parrilli, Michelangelo; Schiraldi, Chiara; D'Agostino, Antonella; Izzo, Elisabetta; Rizza, Luisa; Bonina, Andrea; Bonina, Francesco; Lanzetta, Rosa

2017-02-10

The Opuntia ficus-indica multiple properties are reflected in the increasing interest of chemists in the identification of its natural components having pharmaceutical and/or cosmetical applications. Here we report the structural elucidation of Opuntia ficus-indica mucilage that highlighted the presence of components differing for their chemical nature and the molecular weight distribution. The high molecular weight components were identified as a linear galactan polymer and a highly branched xyloarabinan. The low molecular weight components were identified as lactic acid, D-mannitol, piscidic, eucomic and 2-hydroxy-4-(4'-hydroxyphenyl)-butanoic acids. A wound healing assay was performed in order to test the cicatrizing properties of the various components, highlighting the ability of these latter to fasten dermal regeneration using a simplified in vitro cellular model based on a scratched keratinocytes monolayer. The results showed that the whole Opuntia mucilage and the low molecular weight components are active in the wound repair. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of chitosan molecular weight on the properties of alginate ...

African Journals Online (AJOL)

Purpose: The aim of the present study was to investigate the effect of chitosan molecular weight on size, size distribution, release rate, mucoadhesive properties and electrostatic bonding of alginate/chitosan microparticles containing prednisolone. Methods: Three mucoadhesive alginate/chitosan microparticle formulations, ...

Thermal characterization of Ag and Ag + N ion implanted ultra-high molecular weight polyethylene (UHMWPE)

Science.gov (United States)

Sokullu Urkac, E.; Oztarhan, A.; Tihminlioglu, F.; Kaya, N.; Ila, D.; Muntele, C.; Budak, S.; Oks, E.; Nikolaev, A.; Ezdesir, A.; Tek, Z.

2007-08-01

Most of total hip joints are composed of ultra-high molecular weight polyethylene (UHMWPE). However, as ultra-high molecular weight polyethylene is too stable in a body, wear debris may accumulate and cause biological response such as bone absorption and loosening of prosthesis. In this study, ultra-high molecular weight polyethylene samples were Ag and Ag + N hybrid ion implanted by using MEVVA ion implantation technique to improve its surface properties. Samples were implanted with a fluence of 1017 ion/cm2 and extraction voltage of 30 kV. Implanted and unimplanted samples were investigated by thermo-gravimetry analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), optical microscopy (OM) and contact Angle measurement. Thermal characterization results showed that the ion bombardment induced an increase in the % crystallinity, onset and termination degradation temperatures of UHMWPE.

Developmental co-expression of small molecular weight apolipoprotein B synthesis and triacylglycerol secretion

International Nuclear Information System (INIS)

Coleman, R.A.; Haynes, E.B.; Sand, T.M.; Davis, R.A.

1987-01-01

The development of the liver's ability to coordinately express the synthesis and secretion of the two major components of very low density lipoproteins (VLDL): triacylglycerol (TG) and apolipoprotein B (apo B) was examined in cultured hepatocytes obtained from fetal, suckling and adult rats. Hepatocytes from fetal and suckling rats synthesized and secreted TG at rates lower than that displayed by adult cells. When TG synthesis was equalized by adding oleic acid to the culture medium, fetal cells still secreted only 39% as much TG as did adult cells. To determine the basis for the apparent defect in VLDL assembly/secretion displayed by fetal cells, the synthesis and secretion of [ 35 S]methionine-labeled apo B was quantified by immunoprecipitation. Although adult and fetal cells synthesized and secreted large molecular weight apo B at similar rates, the synthesis and secretion of small molecular weight apo B was 2-fold greater in adult cells. These data suggest that the ability to assemble/secrete VLDL triacylglycerol varies in parallel with the developmental expression of small molecular weight apo B. Furthermore, these studies show the usefulness of the cultured rat hepatocyte model for examining the ontogeny and regulation of VLDL assembly/secretion

[Correlation of molecular weight and nanofiltration mass transfer coefficient of phenolic acid composition from Salvia miltiorrhiza].

Science.gov (United States)

Li, Cun-Yu; Wu, Xin; Gu, Jia-Mei; Li, Hong-Yang; Peng, Guo-Ping

2018-04-01

Based on the molecular sieving and solution-diffusion effect in nanofiltration separation, the correlation between initial concentration and mass transfer coefficient of three typical phenolic acids from Salvia miltiorrhiza was fitted to analyze the relationship among mass transfer coefficient, molecular weight and concentration. The experiment showed a linear relationship between operation pressure and membrane flux. Meanwhile, the membrane flux was gradually decayed with the increase of solute concentration. On the basis of the molecular sieving and solution-diffusion effect, the mass transfer coefficient and initial concentration of three phenolic acids showed a power function relationship, and the regression coefficients were all greater than 0.9. The mass transfer coefficient and molecular weight of three phenolic acids were negatively correlated with each other, and the order from high to low is protocatechualdehyde >rosmarinic acid> salvianolic acid B. The separation mechanism of nanofiltration for phenolic acids was further clarified through the analysis of the correlation of molecular weight and nanofiltration mass transfer coefficient. The findings provide references for nanofiltration separation, especially for traditional Chinese medicine with phenolic acids. Copyright© by the Chinese Pharmaceutical Association.

Obesity with Comorbid Stress Urinary Incontinence in Women: A Narrative Review to Inform Dietetics Practice.

Science.gov (United States)

Gordon, Barbara; Shorter, Barbara; Isoldi, Kathy Keenan; Moldwin, Robert M

2017-06-01

Stress urinary incontinence (SUI) is a common problem among women; clinical treatment guidelines include weight reduction as a strategy for controlling urinary leakage. The purpose of this review was to gather evidence on the association between obesity and SUI and to ascertain whether there are any special considerations for implementing medical nutrition therapy with community-dwelling, obese, adult females with comorbid SUI. Five key findings emerged: epidemiologic studies consistently report statistically significant associations between obesity and SUI, randomized control trials found that weight loss appears to ameliorate SUI symptoms, the SUI-activity link may affect weight management, there is a potential interplay between SUI and the obesity-sleep connection, and dietary components are associated with the exacerbation of urinary symptoms. The pathogenesis of SUI and obesity-related contributions to urinary leakage is included in the introductory discussion. Lastly, insights on special considerations for implementing nutrition interventions with this population are offered. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Effect of various solvents on the viscosity-average molecular weight of poly (vinyl acetate)

International Nuclear Information System (INIS)

Rehman, W.U.; But, M.A.; Chughtai, A.; Jamil, T.; Sattar, A.

2006-01-01

Solution polymerization of Vinyl Acetate was carried out in various solvents (benzene, toluene, ethyl acetate, acetonitrile). Dilute solution viscometry was used to determine the viscosity-average molecular weight of the resulting Poly (Vinyl Acetate) (PV Ac) in each case. The viscosity-average molecular weight (M,J of PVAc was found to increase in the order benzene < toluene < ethyl acetate < acetonitrile, It was concluded that under the same reaction conditions (polymerization time, initiator quantity, solvent/monomer ratio, temperature), acetonitrile served as the best solvent for solution. polymerization of Vinyl Acetate monomer. (author)

Rheological properties of poly(vinylpiyrrolidone) as a function of molecular weight

DEFF Research Database (Denmark)

Marani, Debora; Sudireddy, Bhaskar Reddy; Kiebach, Wolff-Ragnar

2014-01-01

Different grades of poly (vinylpyrrolidone) (PVP) were studied as dispersant for gadolinium doped cerium oxide (CGO) in ethanol-based colloidal dispersions. The average molecular weights Mw, Mn, and Mz were determined by gel permeation chromatography (GPC), and then used in a numerical method...

Safety of low-molecular-weight heparin in pregnancy: a systematic review

NARCIS (Netherlands)

Sanson, B. J.; Lensing, A. W.; Prins, M. H.; Ginsberg, J. S.; Barkagan, Z. S.; Lavenne-Pardonge, E.; Brenner, B.; Dulitzky, M.; Nielsen, J. D.; Boda, Z.; Turi, S.; Mac Gillavry, M. R.; Hamulyák, K.; Theunissen, I. M.; Hunt, B. J.; Büller, H. R.

1999-01-01

Unfractionated heparin (UFH) remains the anticoagulant of choice during pregnancy. Low-molecular-weight heparins (LMWH) are an attractive alternative to UFH due to their logistic advantages and their association with a lower incidence of osteoporosis and HIT. We reviewed all published clinical

Low-molecular-weight carbohydrates from red seaweeds

International Nuclear Information System (INIS)

Duarte, M.E.R.; Tischer, C.A.; Gorin, P.A.J.; Noseda, M.D.

1997-01-01

Red algae (Rhodophyta) produce, as their principal photosynthetic metabolites, low-molecular-weight carbohydrates and polyols. The former are heterosides consisting of galactose and glycerol and are produced by all the orders of Phodophyta except the ceramiales. They are named: floridoside [α-D-galactopyranosyl (1->2)-glycerol], isofloridoside D-form [α-D-galactopyranosyl-(1->)D-glycerol] and L-form [α-D-galactopyranosyl-(1->1)-L-glycerol] (Meng et al., 1987, Karsten et al., 1993). The Ceramiales synthesize the chemically related digeneaside [α-D-mannopyranosyl-(1->2)-L-glycerate] (Kirst, 1980). Some of the red seaweeds also produce polyols such as dulcitol and D-sorbitol (Karsten et al., 1992). (author)

Update on the clinical use of the low-molecular-weight heparin, parnaparin

Directory of Open Access Journals (Sweden)

Giuseppe Camporese

2009-09-01

Full Text Available Giuseppe Camporese1, Enrico Bernardi2, Franco Noventa31Unit of Angiology and 3Department of Clinical and Experimental Medicine, Clinical Epidemiology Group, University Hospital of Padua, Italy; 2Department of Emergency and Accident Medicine, Hospital of Conegliano Veneto, ItalyAbstract: Parnaparin is a low-molecular-weight heparin that has widely shown its efficacy and safety in prevention of venous thromboembolism, in the treatment of chronic venous disorders, and in the treatment of venous and arterial (stable and unstable angina, acute ST-segment elevation myocardial infarction thrombosis. Parnaparin at the respective dosages of 3200, 4250, 6400, or 12800 IUaXa for a period ranging from 3 to 5 days to 6 months, is usually administered subcutaneously by means of once-daily regimen and is better tolerated than unfractionated heparin at the injection site. In the variety of commercially available low-molecular-weight heparins, parnaparin represents a useful therapeutic option, even though little evidence is available comparing the superiority or the equivalent efficacy and safety of parnaparin to that of the unfractionated heparin or placebo. This review summarizes the available literature on the use of parnaparin in different settings of cardiovascular diseases, including papers published during the past year and ongoing studies.Keywords: low-molecular-weight heparin, heparin, parnaparin, acute coronary syndromes, venous thromboembolism

Thermal characterization of Ag and Ag + N ion implanted ultra-high molecular weight polyethylene (UHMWPE)

Energy Technology Data Exchange (ETDEWEB)

Sokullu Urkac, E. [Department of Materials Science, Izmir High Technology Institute, Gulbahcekoyu Urla, Izmir (Turkey)]. E-mail: emelsu@gmail.com; Oztarhan, A. [Bioengineering Department, Ege University, Bornova, Izmir 35100 (Turkey); Tihminlioglu, F. [Department of Chemical Engineering, Izmir High Technology Institute, Gulbahcekoyu Urla, Izmir (Turkey); Kaya, N. [Bioengineering Department, Ege University, Bornova, Izmir 35100 (Turkey); Ila, D. [Center for Irradiation of Materials, Alabama A and M University, Normal AL 35762 (United States); Muntele, C. [Center for Irradiation of Materials, Alabama A and M University, Normal AL 35762 (United States); Budak, S. [Center for Irradiation of Materials, Alabama A and M University, Normal AL 35762 (United States); Oks, E. [H C Electronics Institute, Tomsk (Russian Federation); Nikolaev, A. [H C Electronics Institute, Tomsk (Russian Federation); Ezdesir, A. [R and D Department, PETKIM Holding A.S., Aliaga, Izmir 35801 (Turkey); Tek, Z. [Department of Physics, Celal Bayar University, Manisa (Turkey)

2007-08-15

Most of total hip joints are composed of ultra-high molecular weight polyethylene (UHMWPE ). However, as ultra-high molecular weight polyethylene is too stable in a body, wear debris may accumulate and cause biological response such as bone absorption and loosening of prosthesis. In this study, ultra-high molecular weight polyethylene samples were Ag and Ag + N hybrid ion implanted by using MEVVA ion implantation technique to improve its surface properties. Samples were implanted with a fluence of 10{sup 17} ion/cm{sup 2} and extraction voltage of 30 kV. Implanted and unimplanted samples were investigated by thermo-gravimetry analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), optical microscopy (OM) and contact Angle measurement. Thermal characterization results showed that the ion bombardment induced an increase in the % crystallinity, onset and termination degradation temperatures of UHMWPE.

Effects of ionizing radiation on the properties of ultra-high molecular weight polyethylene (PE-UHMW)

International Nuclear Information System (INIS)

Kurth, M.

1990-01-01

Ultra high molecular weight polyethylene (PE-UHMW) is used in most artificial joint replacement devices. Prior to implantation in biological environment, radiatin sterilization by 60 Co or electron beam is common. It is well known that polyethylene exposed to ionizing radiation of any sort undergo physical changes due to chain scission and/or crosslinking. PE-UHMW sheets, 8 mm thick, were either 60 Co or electron beam irradiated, in the range of 10-150 kGy under air or nitrogen atmoshere. The crystallinity of the irradiated samples increases with the irradiation dose. The chain scission/crosslinking events ratio determine the network structure and the sol/gel ratio. The latter was found to depend on irradiation dose, radiation atmosphere and sample thickness. Moreover 60 Co-irradiation is about 5 times more effective in forming PE-UHMW gel than electron-irradiation. Besides the degree of crosslinking, the molecular weight distribution is the main determinant of the structural properties of PE-UHMW. Low molecular weight fractions were also found. Using a dose of 30 kGy ( 60 Co in air), the average molecular weight of the soluble part after extraction decreased from originally 2.3 million g/mol to 170.000 g/mol, corresponding to a factor of about 10. These changes in molecular weight have a strong influence on the mechanical properties of PE-UHMW. Crosslinking slightly increases the yield strength, while the elongation at break decreases. Long-term compressive creep is reduced if the material is irradiated. Obviously, increased crystallinity after oxidative chain scission affects a higher deformation resistance. Radiation crosslinked structures cause a significant increase in abrasion resistance. The above described structural changes occur even upon irradiation of very low doses as used during sterilization. This study will enable to reduce the radiation sterilization damage and thus to gain long term stability of PE-UHMW medical devices. (orig./BBR)

Role of Molecular Weight on the Mechanical Device Properties of Organic Polymer Solar Cells

KAUST Repository

Bruner, Christopher

2014-02-11

For semiconducting polymers, such as regioregular poly(3-hexylthiophene-2, 5-diyl) (rr-P3HT), the molecular weight has been correlated to charge carrier field-effect mobilities, surface morphology, and gelation rates in solution and therefore has important implications for long-Term reliability, manufacturing, and future applications of electronic organic thin films. In this work, we show that the molecular weight rr-P3HT in organic solar cells can also significantly change the internal cohesion of the photoactive layer using micromechanical testing techniques. Cohesive values ranged from ∼0.5 to ∼17 J m -2, following the general trend of greater cohesion with increasing molecular weight. Using nanodynamic mechanical analysis, we attribute the increase in cohesion to increased plasticity which helps dissipate the applied energy. Finally, we correlate photovoltaic efficiency with cohesion to assess the device physics pertinent to optimizing device reliability. This research elucidates the fundamental parameters which affect both the mechanical stability and efficiency of polymer solar cells. © 2014 American Chemical Society.

Molecular-weight distributions of coal and petroleum asphaltenes from laser desorption/ionization experiments

Energy Technology Data Exchange (ETDEWEB)

Ana R. Hortal; Paola Hurtado; Bruno Martinez-Haya; Oliver C. Mullins [Universidad Pablo de Olavide, Seville (Spain). Departamento de Sistemas Fisicos, Quimicos y Naturales

2007-09-15

Molecular-weight distributions (MWDs) of asphaltenes extracted from coal and petroleum have been measured in laser desorption/ionization (LDI) mass spectrometric experiments. The dried-droplet and solvent-free sample preparation methods are compared. The coal asphaltenes have a relatively narrow MWD (full width 150 amu) with an average molecular weight of 340 amu. The petroleum asphaltenes display a broader MWD (full width 300 amu) and are heavier on average (680 amu). The LDI spectra also provide evidence for the formation of noncovalent clusters of the two types of asphaltenes during the desorption process. Petroleum and coal asphaltenes exhibit aggregation as do large model polycyclic aromatic hydrocarbons (PAHs) with five or more fused rings also included in the study. Smaller PAHs (pyrene) exhibit less aggregation, especially when alkane-chain substituents are incorporated to the molecular structure. This indicates that asphaltenes possess large PAHs and, according to the relatively small molecular weights observed, that there is a preponderance of asphaltene molecules with only a single fused ring system. The coal asphaltenes present a significantly smaller propensity toward aggregation than their crude oil counterparts. This finding, coupled with the fact that (1) alkanes inhibit aggregation in LDI and (2) petroleum asphaltenes possess much more alkane carbon, indicates that coal asphaltenes have smaller PAHs on average than petroleum asphaltenes. This is further corroborated by the stronger ultraviolet absorbance of the coal asphaltenes at wavelengths shorter than 400 nm. 32 refs., 8 figs.

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants.

Science.gov (United States)

Simal-Gándara, J; Sarria-Vidal, M; Rijk, R

2000-09-01

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.

Effect of molecular weight and glass transition on relaxation and release behaviour of poly(DL-lactic acid) tablets

NARCIS (Netherlands)

Steendam, R.; Van Steenbergen, M.J.; Hennink, W.E.; Frijlink, H.W.; Lerk, C.F.

2001-01-01

Different molecular weight grades of poly(DL-lactic acid) were applied as release controlling excipients in tablets for oral drug administration. The role of molecular weight and glass transition in the mechanism of water-induced volume expansion and drug release of PDLA tablets was investigated.

Personal Care Product Use in Men and Urinary Concentrations of Select Phthalate Metabolites and Parabens

DEFF Research Database (Denmark)

Nassan, Feiby L; Coull, Brent A; Gaskins, Audrey J

2017-01-01

BACKGROUND: Personal care products (PCPs) are exposure sources to phthalates and parabens; however, their contribution to men's exposure is understudied. OBJECTIVES: We examined the association between PCP use and urinary concentrations of phthalate metabolites and parabens in men. METHODS...... in urinary concentrations associated with PCP use using linear mixed and Tobit mixed regressions. We also estimated weights for each PCP in a weighted binary score regression and modeled the resulting composite weighted PCP use. RESULTS: Four hundred men contributed 1,037 urine samples (mean of 3/man...

Should Low Molecular Weight PSMA Targeted Ligands Get Bigger and Use Albumin Ligands for PSMA Targeting?

OpenAIRE

Huang, Steve S.; Heston, Warren D.W.

2017-01-01

Prostate Specific Membrane Antigen (PSMA) is strongly expressed in prostate cancer. Recently a number of low-molecular-weight inhibitors have demonstrated excellent PSMA targeting activity for both imaging as well as Lutecium-177 radiotherapy in human trials. The paper by Choy et al raises the question of whether we can further increase the effectiveness of PSMA targeted therapy by adding an albumin-binding entity to low-molecular-weight agents

Low molecular weight compounds as effective dispersing agents in the formation of colloidal silver nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Natsuki, Jun; Natsuki, Toshiaki, E-mail: natsuki@shinshu-u.ac.jp; Abe, Takao [Shinshu University, Faculty of Textile Science and Technology (Japan)

2013-03-15

A convenient method to synthesize uniform, well-dispersed colloidal silver nanoparticles is described. Aldonic acid or {alpha}-hydroxy acid compounds of low molecular weight are used instead of polymeric compounds as dispersing agents to prepare silver nanoparticles. The size, conformation, and electrical conductivity of the silver nanoparticles, and the effect and function of the dispersing agents are investigated in detail. Using these low molecular weight compounds as dispersing agents, silver nanoparticles with a diameter of 10 nm or less and high electrical conductivity can be obtained. In addition, this procedure allows silver nanoparticles to be sintered at 150 Degree-Sign C, which is lower than that required for silver nanoparticle formulation using polymeric compounds (200 Degree-Sign C). The silver nanoparticles produced by this process can be used to prepare various inks and to manufacture electronic circuits. It is found that low molecular weight compounds are more effective dispersing agents than polymeric compounds in the formation of silver nanoparticles.

Low molecular weight chitosan conjugated with folate for siRNA delivery in vitro: optimization studies

Science.gov (United States)

Fernandes, Julio C; Qiu, Xingping; Winnik, Francoise M; Benderdour, Mohamed; Zhang, Xiaoling; Dai, Kerong; Shi, Qin

2012-01-01

The low transfection efficiency of chitosan is one of its drawbacks as a gene delivery carrier. Low molecular weight chitosan may help to form small-sized polymer-DNA or small interfering RNA (siRNA) complexes. Folate conjugation may improve gene transfection efficiency because of the promoted uptake of folate receptor-bearing cells. In the present study, chitosan was conjugated with folate and investigated for its efficacy as a delivery vector for siRNA in vitro. We demonstrate that the molecular weight of chitosan has a major influence on its biological and physicochemical properties, and very low molecular weight chitosan (below 10 kDa) has difficulty in forming stable complexes with siRNA. In this study, chitosan 25 kDa and 50 kDa completely absorbed siRNA and formed nanoparticles (≤220 nm) at a chitosan to siRNA weight ratio of 50:1. The introduction of a folate ligand onto chitosan decreased nanoparticle toxicity. Compared with chitosan-siRNA, folate-chitosan-siRNA nanoparticles improved gene silencing transfection efficiency. Therefore, folate-chitosan shows potential as a viable candidate vector for safe and efficient siRNA delivery. PMID:23209368

[Urinary incontinence 6 months after childbirth].

Science.gov (United States)

Ruiz de Viñaspre Hernández, Regina; Rubio Aranda, Encarnación; Tomás Aznar, Concepción

2013-08-17

Urinary incontinence initiated before and right after delivery and persisting 3 months after delivery tends to become chronic. We intended to estimate the persistence of urinary incontinence 6 months postpartum and to analyse the different factors associated with it. Follow-up study 6 months after delivery of women presenting urinary incontinence symptoms in gestation or in the first 2 months of postpartum. The dependent variable was the persistence and the independent variables were grouped in obstetric and non-obstetric. Odds ratio (OR) were calculated with their confidence interval at 95% (IC 95%) in the bivariate analysis. The variables that showed an important risk of persistence of incontinence were used to perform a multivariate model of logistic regression. The persistence of incontinence 6 months after delivery was 21.4% (CI 95% 16-26.7). The risk of persistence increased with the Kristeller maneuver (OR 7.89, CI 95% 3.04-20.49), not weight recovery (OR 3.64, CI 95% 1.10-12.02), not practising pelvic floor muscle exercises in postpartum (OR 9.36, CI 95% 2.71-32.33), appearance of incontinence after delivery (OR 6.66, CI 95% 2.37-18.68) and the weight of the newborn>3.5 kg (OR 6.76, CI 95% 2.54-18.03), all of them explaining 58% of the variability of persistence. 21.4% of women with urinary incontinence caused by pregnancy/delivery will continue to have it 6 months postpartum. An important part of this persistence is associated with some factors easy to modify. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Improved synthesis with high yield and increased molecular weight of poly(alpha,beta-malic acid) by direct polycondensation.

Science.gov (United States)

Kajiyama, Tetsuto; Kobayashi, Hisatoshi; Taguchi, Tetsushi; Kataoka, Kazunori; Tanaka, Junzo

2004-01-01

The development of synthetic biodegradable polymers, such as poly(alpha-hydroxy acid), is particularly important for constructing medical devices, including scaffolds and sutures, and has attracted growing interest in the biomedical field. Here, we report a novel approach to preparing high molecular weight poly(malic acid) (HMW--PMA) as a biodegradable and bioabsorbable water-soluble polymer. We investigated in detail the reaction conditions for the simple direct polycondensation of l-malic acid, including the reaction times, temperatures, and catalysts. The molecular weight of synthesized alpha,beta-PMA is dependent on both the reaction temperature and time. The optimum reaction condition to obtain alpha,beta-PMA by direct polycondensation using tin(II) chloride as a catalyst was thus determined to be 110 degrees C for 45 h with a molecular weight of 5300. The method for alpha,beta-PMA synthesis established here will facilitate production of alpha,beta-PMA of various molecular weights, which may have a potential utility as biomaterials.

Inulin in Medicinal Plants (IV) : Reversed-Phase High-Performance Liquid Chromatography of Inulin after Acetylation : Molecular-Weight Distribution of Inulin in Medicinal Plants

OpenAIRE

三野, 芳紀; 筒井, 聡美; 太田, 長世; YOSHIKI, MINO; SATOMI, TSUTSUI; NAGAYO, OTA; 大阪薬科大学; 大阪薬科大学; 大阪薬科大学; Osaka College of Pharmacy; Osaka College of Pharmacy; Osaka College of Pharmacy

1985-01-01

Reversed-phase high-performance liquid chromatography coupled with pre-acetylation enabled acculate molecular-weight assay of inulin in medicinal plants to be conducted. The results clearly showed that the molecular-weight distribution of inulin varied depending on the stage of growth: Small molecular weight inulin polymers were detected in large quantity in the earlier growth stage whereas large molecular weight inulin polymers at the flowering and post flowering period.

Low-molecular-weight carbohydrates from red seaweeds

Energy Technology Data Exchange (ETDEWEB)

Duarte, M.E.R.; Tischer, C.A.; Gorin, P.A.J.; Noseda, M.D. [Parana Univ., Curitiba, PR (Brazil). Dept. de Bioquimica

1997-12-31

Red algae (Rhodophyta) produce, as their principal photosynthetic metabolites, low-molecular-weight carbohydrates and polyols. The former are heterosides consisting of galactose and glycerol and are produced by all the orders of Phodophyta except the ceramiales. They are named: floridoside [{alpha}-D-galactopyranosyl (1->2)-glycerol], isofloridoside D-form [{alpha}-D-galactopyranosyl-(1->)D-glycerol] and L-form [{alpha}-D-galactopyranosyl-(1->1)-L-glycerol] (Meng et al., 1987, Karsten et al., 1993). The Ceramiales synthesize the chemically related digeneaside [{alpha}-D-mannopyranosyl-(1->2)-L-glycerate] (Kirst, 1980). Some of the red seaweeds also produce polyols such as dulcitol and D-sorbitol (Karsten et al., 1992). (author) 4 refs., 8 figs., 1 tabs.

Total protein, albumin and low-molecular-weight protein excretion in HIV-positive patients

Directory of Open Access Journals (Sweden)

Campbell Lucy J

2012-08-01

Full Text Available Abstract Background Chronic kidney disease is common in HIV positive patients and renal tubular dysfunction has been reported in those receiving combination antiretroviral therapy (cART. Tenofovir (TFV in particular has been linked to severe renal tubular disease as well as proximal tubular dysfunction. Markedly elevated urinary concentrations of retinal-binding protein (RBP have been reported in patients with severe renal tubular disease, and low-molecular-weight proteins (LMWP such as RBP may be useful in clinical practice to assess renal tubular function in patients receiving TFV. We analysed 3 LMWP as well as protein and albumin in the urine of a sample of HIV positive patients. Methods In a cross-sectional fashion, total protein, albumin, RBP, cystatin C, and neutrophil gelatinase-associated lipocalin (NGAL were quantified in random urine samples of 317 HIV positive outpatients and expressed as the ratio-to-creatinine (RBPCR, CCR and NGALCR. Exposure to cART was categorised as none, cART without TFV, and cART containing TFV and a non-nucleoside reverse-transcriptase-inhibitor (TFV/NNRTI or TFV and a protease-inhibitor (TFV/PI. Results Proteinuria was present in 10.4 % and microalbuminuria in 16.7 % of patients. Albumin accounted for approximately 10 % of total urinary protein. RBPCR was within the reference range in 95 % of patients while NGALCR was elevated in 67 % of patients. No overall differences in urine protein, albumin, and LMWP levels were observed among patients stratified by cART exposure, although a greater proportion of patients exposed to TFV/PI had RBPCR >38.8 μg/mmol (343 μg/g (p = 0.003. In multivariate analyses, black ethnicity (OR 0.43, 95 % CI 0.24, 0.77 and eGFR 2 (OR 3.54, 95 % CI 1.61, 7.80 were independently associated with upper quartile (UQ RBPCR. RBPCR correlated well to CCR (r2 = 0.71, but not to NGALCR, PCR or ACR. Conclusions In HIV positive patients, proteinuria was predominantly of

Effects of molecular weight of natural organic matter on cadmium mobility in soil environments and its carbon isotope characteristics

International Nuclear Information System (INIS)

Mahara, Y.; Kubota, T.; Wakayama, R.; Nakano-Ohta, T.; Nakamura, T.

2007-01-01

We investigated the role of natural organic matter in cadmium mobility in soil environments. We collected the dissolved organic matter from two different types of natural waters: pond surface water, which is oxic, and deep anoxic groundwater. The collected organic matter was fractionated into four groups with molecular weights (unit: Da (Daltons)) of 3 , 1-10 x 10 3 , 10-100 x 10 3 , and > 100 x 10 3 . The organic matter source was land plants, based on the carbon isotope ratios (δ 13 C/ 12 C). The organic matter in surface water originated from presently growing land plants, based on 14 C dating, but the organic matter in deep groundwater originated from land plants that grew approximately 4000 years ago. However, some carbon was supplied by the high-molecular-weight fraction of humic substances in soil or sediments. Cadmium interacted in a system of siliceous sand, fractionated organic matter, and water. The lowest molecular weight fraction of organic matter ( 3 ) bound more cadmium than did the higher molecular weight fractions. Organic matter in deep groundwater was more strongly bound to cadmium than was organic matter in surface water. The binding behaviours of organic matter with cadmium depended on concentration, age, molecular weight, and degradation conditions of the organic matter in natural waters. Consequently, the dissolved, low-molecular-weight fraction in organic matter strongly influences cadmium migration and mobility in the environment

Preparation of the low molecular weight serum proteome for mass spectrometry analysis.

Science.gov (United States)

Waybright, Timothy J; Chan, King C; Veenstra, Timothy D; Xiao, Zhen

2013-01-01

The discovery of viable biomarkers or indicators of disease states is complicated by the inherent complexity of the chosen biological specimen. Every sample, whether it is serum, plasma, urine, tissue, cells, or a host of others, contains thousands of large and small components, each interacting in multiple ways. The need to concentrate on a group of these components to narrow the focus on a potential biomarker candidate becomes, out of necessity, a priority, especially in the search for immune-related low molecular weight serum biomarkers. One such method in the field of proteomics is to divide the sample proteome into groups based on the size of the protein, analyze each group, and mine the data for statistically significant items. This chapter details a portion of this method, concentrating on a method for fractionating and analyzing the low molecular weight proteome of human serum.

MALDI matrices for low molecular weight compounds: an endless story?

Science.gov (United States)

Calvano, Cosima Damiana; Monopoli, Antonio; Cataldi, Tommaso R I; Palmisano, Francesco

2018-04-23

Since its introduction in the 1980s, matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) has gained a prominent role in the analysis of high molecular weight biomolecules such as proteins, peptides, oligonucleotides, and polysaccharides. Its application to low molecular weight compounds has remained for long time challenging due to the spectral interferences produced by conventional organic matrices in the low m/z window. To overcome this problem, specific sample preparation such as analyte/matrix derivatization, addition of dopants, or sophisticated deposition technique especially useful for imaging experiments, have been proposed. Alternative approaches based on second generation (rationally designed) organic matrices, ionic liquids, and inorganic matrices, including metallic nanoparticles, have been the object of intense and continuous research efforts. Definite evidences are now provided that MALDI MS represents a powerful and invaluable analytical tool also for small molecules, including their quantification, thus opening new, exciting applications in metabolomics and imaging mass spectrometry. This review is intended to offer a concise critical overview of the most recent achievements about MALDI matrices capable of specifically address the challenging issue of small molecules analysis. Graphical abstract An ideal Book of matrices for MALDI MS of small molecules.

Equal channel angular extrusion of ultra-high molecular weight polyethylene

Energy Technology Data Exchange (ETDEWEB)

Reinitz, Steven D., E-mail: Steven.D.Reinitz.TH@Dartmouth.edu; Engler, Alexander J.; Carlson, Evan M.; Van Citters, Douglas W.

2016-10-01

Ultra-high molecular weight polyethylene (UHMWPE), a common bearing surface in total joint arthroplasty, is subject to material property tradeoffs associated with conventional processing techniques. For orthopaedic applications, radiation-induced cross-linking is used to enhance the wear resistance of the material, but cross-linking also restricts relative chain movement in the amorphous regions and hence decreases toughness. Equal Channel Angular Extrusion (ECAE) is proposed as a novel mechanism by which entanglements can be introduced to the polymer bulk during consolidation, with the aim of imparting the same tribological benefits of conventional processing without complete inhibition of chain motion. ECAE processing at temperatures near the crystalline melt for UHMWPE produces (1) increased entanglements compared to control materials; (2) increasing entanglements with increasing temperature; and (3) mechanical properties between values for untreated polyethylene and for cross-linked polyethylene. These results support additional research in ECAE-processed UHMWPE for joint arthroplasty applications. - Highlights: • A new processing method for ultra-high molecular weight polyethylene is introduced. • The process produces a highly entangled polyethylene material. • Entanglements are hypothesized to enhance the wear resistance of polyethylene. • This process eliminates the trade-off between mechanical and wear properties.

Control of radio degradation of natural polymers by measurement of viscosity and molecular weight determination

International Nuclear Information System (INIS)

Nabinger Machado, Patricia; Cerchietti, Maria Luciana; Mondino, Angel V.; Smolko, Eduardo E.

2009-01-01

Applications are now being made in various fields of oligosaccharides obtained by the depolymerization of large molecules such as natural alginates, carrageenan, pectin and chitosan. Find use in various disciplines such as crop production, sanitation, pharmacy, cosmetics, etc. Given the diversity of origins of these materials, almost all of marine origin, was the need for universal methods for recognition and composition, then the possible ways to get processed. A centralized program by the IAEA is promoting the use of ionizing radiation for these changes. This paper resents the calculations used to obtain the molecular weight of polysaccharides from determinations of viscosity. It has been found the molecular weight of sodium alginate and kappa-carrageenan irradiated with cobalt-60 gamma rays at doses between 2 and 35 kGy in solid state. We used a capillary Cannon Viscometer Ubbelohde-type and a protocol for standardized calculation procedure for this purpose. Were obtained reading times for passage through the capillary Viscometer, with various concentrations of polymer solutions of virgin material and the irradiated and from there calculated the relative viscosities, specific, inherent, reduced and intrinsic and then using the ratio of Mark-Houwink-SAKURADA calculate the viscosity average molecular weight of the different polymers. The changes found in the molecular weights by radio-depolymerization reach two orders of magnitude in some cases giving oligosaccharides of 8-12 monomer units. It is considered that this depolymerization method is effective and inexpensive compared to enzymatic or chemical methods. (author)

Urinary Bisphenol A Concentration and Gestational Diabetes Mellitus in Chinese Women.

Science.gov (United States)

Wang, Xia; Wang, Xu; Chen, Qian; Luo, Zhong-Cheng; Zhao, Shasha; Wang, Weiye; Zhang, Hui-Juan; Zhang, Jun; Ouyang, Fengxiu

2017-10-01

Bisphenol A (BPA) has been associated with variable metabolic effects in animal models. It is unknown whether BPA exposure affects glucose tolerance in pregnancy. We aimed to investigate whether maternal urinary BPA concentration is associated with gestational diabetes mellitus (GDM). This study included 620 pregnant women from Shanghai, China 2012-2013. Maternal urinary BPA concentration was measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). GDM (n = 79) was diagnosed according to the criteria of the International Association of Diabetes and Pregnancy Study Groups (IADPSG). Multivariate regressions were used to explore the relationships of urinary BPA with GDM, plasma glucose levels in the 75-g 2-hour oral glucose tolerance test (OGTT), birth weight, and ponder index. The geometric mean of BPA was 1.32 μg/L. After adjustment for maternal age, education, husband smoking status, prepregnancy body mass index (BMI), and urinary creatinine concentration, plasma glucose at 2 hours in the 75-g OGTT was 0.36 mmol/L lower (95% confidence index [CI] = -0.73, 0.01) for women with urine BPA in the high versus the low tertile. For each unit increase in natural log-transformed BPA, the odds of GDM was reduced by 27% (odds ratio (OR) = 0.73; 95% CI = 0.56, 0.97), the birth weight decreased by 25.70 g (95% CI = -54.48, 3.07), and ponder index was decreased by 0.02 (100 g/cm) (95% CI = -0.03, 0.00). Higher maternal urinary BPA concentrations were associated with reduced risk of GDM and marginally lower birth weight and ponder index.

Venous thromboembolism in pregnancy: prophylaxis and treatment with low molecular weight heparin

DEFF Research Database (Denmark)

Andersen, Anita Sylvest; Berthelsen, Jørgen G; Bergholt, Thomas

2010-01-01

OBJECTIVE: To evaluate the safety of individually dosed low molecular weight heparin (LMWH) for prophylaxis and treatment of thromboembolic complications in pregnancy. DESIGN: Cohort study with a chronologic register-based control group. SETTING: Department of Obstetrics and Gynecology, Hillerød ...

Adhesives, fillers & potting compounds: Special report molecular weight determinations of dimethypolysiloxane polymers

Energy Technology Data Exchange (ETDEWEB)

Luthey, Z.A.

1968-09-03

Using a Mechrolab Vapor Phase Osmometer and a Hallikainen Automatic Membrane Osmometer the number-average molecular weight of two samples of dimethylpolysiloxane - 2300 and 8000 cstk - as well as samples made by mixing the two previously mentioned materials were determined.

Effects of Low-Molecular-Weight Fucoidan and High Stability Fucoxanthin on Glucose Homeostasis, Lipid Metabolism, and Liver Function in a Mouse Model of Type II Diabetes

Directory of Open Access Journals (Sweden)

Hong-Ting Victor Lin

2017-04-01

Full Text Available The combined effects of low-molecular-weight fucoidan (LMF and fucoxanthin (Fx in terms of antihyperglycemic, antihyperlipidemic, and hepatoprotective activities were investigated in a mouse model of type II diabetes. The intake of LMF, Fx, and LMF + Fx lowered the blood sugar and fasting blood sugar levels, and increased serum adiponectin levels. The significant decrease in urinary sugar was only observed in LMF + Fx supplementation. LMF and Fx had ameliorating effects on the hepatic tissue of db/db mice by increasing hepatic glycogen and antioxidative enzymes, and LMF was more effective than Fx at improving hepatic glucose metabolism. As for glucose and lipid metabolism in the adipose tissue, the expression of insulin receptor substrate (IRS-1, glucose transporter (GLUT, peroxisome proliferator-activated receptor gamma (PPARγ, and uncoupling protein (UCP-1 mRNAs in the adipose tissue of diabetic mice was significantly upregulated by Fx and LMF + Fx, and levels of inflammatory adipocytokines, such as adiponectin, tumor necrosis factor-α (TNF-α, and interleukin-6 (IL-6, were significantly modulated only by LMF + Fx supplementation. The efficacy of LMF + Fx supplementation on the decrease in urinary sugar and on glucose and lipid metabolism in the white adipose tissue of db/db mice was better than that of Fx or LMF alone, indicating the occurrence of a synergistic effect of LMF and Fx.

Solvent extraction of cerium (III) with high molecular weight amines

International Nuclear Information System (INIS)

Chatterjee, A.; Basu, S.

1992-01-01

The use of high molecular weight amines in the extraction of cerium (III) as EDTA complex from neutral aqueous medium is reported. The extraction condition was optimised from the study of effects of several variables like concentration of amine and EDTA pH nature of diluents etc. The method has been applied for the determination of cerium in few mineral samples. (author). 7 refs., 5 tabs

Correlation between the estimated molecular weight and the immunological properties of 125I-TSH

International Nuclear Information System (INIS)

Quiroga, S.E.; Ciscato, V.A.; Barmasch, M.; Kurcbart, H.; Veira de Giacomini, S.; Altschuler, N.; Caro, R.A.

1976-09-01

Thyrotropic Stimulating Hormone (TSH) was radioiodinated by the Chloramine T method in order to be used in radioimmu-noassay procedures. It was purified by gel filtration and each fraction of the eluate was analyzed in order to determine which one had the most suitable behaviour for that use. The molecular weight of each fraction was estimated, as well as its immunological reactivity and its non-specific binding. The 125 I-TSH fraction with better properties was the closest to the molecular weight of the native hormone, which is found at the posterior shoulder of the main proteic peak of the elution pattern. (author) [es

Photocuring of stimulus responsive membranes for controlled-release of drugs having different molecular weights

International Nuclear Information System (INIS)

Ng, Loo-Teck; Nakayama, Hiroshi; Kaetsu, Isao; Uchida, Kumao

2005-01-01

Intelligent drug delivery membranes were prepared by photocuring poly(acrylic acid) coatings onto poly(2-hydroxyethyl methacrylate) membranes each with model drugs of different molecular weights being incorporated. pH-responsive release behaviours of the model drugs which included sodium salicylate, nicotinamide, nicotinic acid, methylene blue, brilliant green and crystal violet were investigated. Only the membrane with methylene blue incorporated showed a clear pH-responsive release and other drug-incorporated membranes showed no intelligent behaviour. These phenomena were explained in terms of the difference in diffusivity of drugs through polymer matrices of the membranes attributable to the difference in the molecular weights of drugs

Photocuring of stimulus responsive membranes for controlled-release of drugs having different molecular weights

Energy Technology Data Exchange (ETDEWEB)

Ng, Loo-Teck [School of Science, Food and Horticulture, University of Western Sydney, Locked bag 1797, Penrith South DC, NSW 1797 (Australia)]. E-mail: l.ng@uws.edu.au; Nakayama, Hiroshi [Department of Nuclear Engineering, Faculty of Science and technology, Kinki University, Kowakae, 3-4-1, Higashi-Osaka 577-8502 (Japan); Kaetsu, Isao [Department of Nuclear Engineering, Faculty of Science and technology, Kinki University, Kowakae, 3-4-1, Higashi-Osaka 577-8502 (Japan)]. E-mail: kaetsu@ned.kindai.ac.jp; Uchida, Kumao [Department of Nuclear Engineering, Faculty of Science and technology, Kinki University, Kowakae, 3-4-1, Higashi-Osaka 577-8502 (Japan)

2005-06-01

Intelligent drug delivery membranes were prepared by photocuring poly(acrylic acid) coatings onto poly(2-hydroxyethyl methacrylate) membranes each with model drugs of different molecular weights being incorporated. pH-responsive release behaviours of the model drugs which included sodium salicylate, nicotinamide, nicotinic acid, methylene blue, brilliant green and crystal violet were investigated. Only the membrane with methylene blue incorporated showed a clear pH-responsive release and other drug-incorporated membranes showed no intelligent behaviour. These phenomena were explained in terms of the difference in diffusivity of drugs through polymer matrices of the membranes attributable to the difference in the molecular weights of drugs.

Ballistic behaviour of ultra-high molecular weight polyethylene: effect of gamma radiation

International Nuclear Information System (INIS)

Alves, Andreia L.S.; Nascimento, Lucio F.C.; Miguez Suarez, Joao Carlos

2004-01-01

The fiber reinforced polymer matrix composites (PMCs) are considered excellent engineering materials. In structural applications, when a high strength-to-weight ratio is fundamental for the design, PMCs are successfully replacing many conventional materials. Since World War II textile materials have been used as ballistic armor. Materials manufactured with ultrahigh molecular weight polyethylene (UHMWPE) fibers are used in the production of armor materials, for personnel protection and armored vehicles. As these have been developed and commercialized more recently, there is not enough information about the action of the ionizing radiation in the ballistic performance of this armor material. In the present work the ballistic behavior of composite plates manufactured with ultrahigh molecular weight polyethylene (UHMWPE) fibers were evaluated after exposure to gamma radiation. The ballistic tests results were related to the macromolecular modifications induced by the environmental degradation through mechanical (hardness, impact and flexure) and physicochemical (infrared spectroscopy, differential scanning calorimetry and thermal gravimetric analysis) tests. Our results indicate that gamma irradiation induces modifications in the UHMWPE macromolecular chains, altering the mechanical properties of the composite and decreasing, for higher radiation doses, its ballistic performance. These results are presented and discussed. (author)

Ozonation of humic substances: Effects on molecular weight distributions of organic carbon and trihalomethane formation potential

International Nuclear Information System (INIS)

Amy, G.L.; Kuo, C.J.; Sierka, R.A.

1988-01-01

Four different sources of humic substances were studied to determine the effects of ozonation on molecular weight distributions, based on dissolved organic carbon (DOC) and trihalomethane formation potential (THMFP). Solutions of two soil-derived fulvic acids and a one soil-derived humic acid, as well as dissolved organic matter (DOM) associated with a natural water source were studied. Both gel permeation chromatography (GPC) and ultrafiltration (UF) were employed to define apparent molecular weight (AMW). Applied ozone doses ranged from 2.0 to 2.5 mg O 3 /mg DOC. Overall samples of untreated and ozonated waters, as well as individual molecular weight fractions, were characterized according to DOC, uv absorbance, and THMFP. Ozonation resulted in a significant disappearance of higher AMW material with a corresponding increase in lower AMW material. Although little overall reduction in DOC concentration was observed, significant overall reductions in UV absorbance and THMFP levels were observed

Cytotoxicity of polycations: Relationship of molecular weight and the hydrolytic theory of the mechanism of toxicity.

Science.gov (United States)

Monnery, Bryn D; Wright, Michael; Cavill, Rachel; Hoogenboom, Richard; Shaunak, Sunil; Steinke, Joachim H G; Thanou, Maya

2017-04-15

The mechanism of polycation cytotoxicity and the relationship to polymer molecular weight is poorly understood. To gain an insight into this important phenomenon a range of newly synthesised uniform (near monodisperse) linear polyethylenimines, commercially available poly(l-lysine)s and two commonly used PEI-based transfectants (broad 22kDa linear and 25kDa branched) were tested for their cytotoxicity against the A549 human lung carcinoma cell line. Cell membrane damage assays (LDH release) and cell viability assays (MTT) showed a strong relationship to dose and polymer molecular weight, and increasing incubation times revealed that even supposedly "non-toxic" low molecular weight polymers still damage cell membranes. The newly proposed mechanism of cell membrane damage is acid catalysed hydrolysis of lipidic phosphoester bonds, which was supported by observations of the hydrolysis of DOPC liposomes. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Lower urinary tract development and disease

Science.gov (United States)

Rasouly, Hila Milo; Lu, Weining

2013-01-01

Congenital Anomalies of the Lower Urinary Tract (CALUT) are a family of birth defects of the ureter, the bladder and the urethra. CALUT includes ureteral anomalies such as congenital abnormalities of the ureteropelvic junction (UPJ) and ureterovesical junction (UVJ), and birth defects of the bladder and the urethra such as bladder-exstrophy-epispadias complex (BEEC), prune belly syndrome (PBS), and posterior urethral valves (PUV). CALUT is one of the most common birth defects and is often associated with antenatal hydronephrosis, vesicoureteral reflux (VUR), urinary tract obstruction, urinary tract infections (UTI), chronic kidney disease and renal failure in children. Here, we discuss the current genetic and molecular knowledge about lower urinary tract development and genetic basis of CALUT in both human and mouse models. We provide an overview of the developmental processes leading to the formation of the ureter, bladder, and urethra, and different genes and signaling pathways controlling these developmental processes. Human genetic disorders that affect the ureter, bladder and urethra and associated gene mutations are also presented. As we are entering the post-genomic era of personalized medicine, information in this article may provide useful interpretation for the genetic and genomic test results collected from patients with lower urinary tract birth defects. With evidence-based interpretations, clinicians may provide more effective personalized therapies to patients and genetic counseling for their families. PMID:23408557

[Comparison of dietary survey, frequency and 24 hour urinary Na methods in evaluation of salt intake in the population].

Science.gov (United States)

Li, Jianhong; Lu, Zilong; Yan, Liuxia; Zhang, Jiyu; Tang, Junli; Cai, Xiaoning; Guo, Xiaolei; Ma, Jixiang; Xu, Aiqiang

2014-12-01

To compare the difference and correlation between dietary salt intakes assessed by 24 hours urinary Na method, food weighted record method and food frequency questionnaire method. All 2 184 subjects aged 18 to 69 were selected by multi stage stratified cluster random sampling method in Shandong province in June to September, 2011. Dietary salt intakes were measured by 24 hours urinary Na method, food weighted record method and food frequency questionnaire method. The information on gender, age, dining locations and labour intensity of members dining at home for 3 days were recorded. And the dietary habits were surveyed by questionnaire. Salt intakes were 14.0, 12.0 and 10.5 g/d assessed by 24 hours urinary Na method, food weighted record method and food frequency questionnaire, respectively. Comparing with 24 hours urinary Na method, salt intakes assessed by food weighted record method and food frequency questionnaire method were 2.0 g (14.3% undervalued) and 3.4 g (24.3% undervalued) less, respectively. Comparing with 24 hours urinary Na method, the proportion of individuals with salt intake over-reported and under-reported were 42.4% (856/2 020) and 55.3% (1 117/2 020) by food weighted record method, and were 20.7% (418/2 020) and 16.3% (329/2 020) by food frequency questionnaire method, respectively; the proportion of individuals with salt intakes within ± 25% of 24 hours urinary Na method were 36.9% (745/2 020) and 28.4% (574/2 020), respectively. Salt intakes assessed by 24 hours urinary method correlated significantly with both salt intakes assessed by food weighted record method and food frequency questionnaire method; the correlation coefficients were 0.13 and 0.07, respectively. With the increasing of salt intakes by subjects' self-judgment, salt intakes were all rising significantly using three survey methods. Salt intakes of three group population of light, moderate and partial taste salty were 13.6, 13.6 and 14.7 g/d by 24 hours urinary Na method (F

Venous thromboembolism in pregnancy: prophylaxis and treatment with low molecular weight heparin

DEFF Research Database (Denmark)

Andersen, Anita Sylvest; Berthelsen, Jørgen G.; Bergholt, Thomas

2010-01-01

OBJECTIVE: To evaluate the safety of individually dosed low molecular weight heparin (LMWH) for prophylaxis and treatment of thromboembolic complications in pregnancy. DESIGN: Cohort study with a chronologic register-based control group. SETTING: Department of Obstetrics and Gynecology, Hillerød...

High Molecular Weight Isoforms of Growth Hormone In Cells of the Immune System

Science.gov (United States)

Weigent, Douglas A.

2013-01-01

A substantial body of research exists to support the idea that cells of the immune system produce growth hormone (GH). However, the structure and mechanism of action of lymphocyte-derived GH continues to remain largely unknown. Here we present the results of Western analysis of whole cell extracts showing that different molecular weight isoforms of GH of approximately 100 kDa, 65 kDa, and 48 kDa can be detected in primary mouse cells of the immune system and in the mouse EL4 cell line. The identity of the 65 kDa and 48 kDa isoforms of GH were confirmed by mass spectrometry. The various isoforms were detected in both enriched T and B spleen cell populations. The large molecular weight isoform appears to reside primarily in the cytoplasm whereas the lower molecular weight 65 kDa and 48 kDa isoforms were detected primarily in the nucleus. These results also suggest that GH isoforms are induced by oxidative stress. In EL4 cells overexpressing GH, the expression of luciferase controlled by a promoter containing the antioxidant response element is increased almost three-fold above control. The data suggest that the induction of isoforms of the GH molecule in cells of the immune system may be an important mechanism of adaptation and/or protection of lymphoid cells under conditions of oxidative stress. PMID:21741628

Effect of coffee drinking on cell proliferation in rat urinary bladder epithelium.

Science.gov (United States)

Lina, B A; Rutten, A A; Woutersen, R A

1993-12-01

A possible effect of freshly brewed drip coffee on urinary bladder carcinogenesis was investigated in male Wistar rats using cell proliferation in urinary bladder epithelium as the indicator of tumour promotion. Male rats were given either undiluted coffee brew (100% coffee), coffee diluted 10 times (10% coffee) or tap water (controls), as their only source of drinking fluid for 2 or 6 wk. Uracil, known to induce cell proliferation in urinary bladder epithelium, was included in the study as a positive control. In rats receiving 100% coffee, body weights, liquid intake and urinary volume were decreased. Neither histopathological examination of urinary bladder tissue nor the bromodeoxyuridine labelling index revealed biologically significant differences between rats receiving coffee and the tap water controls. Uracil increased the labelling index and induced hyperplasia of the urinary bladder epithelium, as expected. It was concluded that these results produced no evidence that drinking coffee predisposes to tumour development in the urinary bladder.

The female urinary microbiome in urgency urinary incontinence.

Science.gov (United States)

Pearce, Meghan M; Zilliox, Michael J; Rosenfeld, Amy B; Thomas-White, Krystal J; Richter, Holly E; Nager, Charles W; Visco, Anthony G; Nygaard, Ingrid E; Barber, Matthew D; Schaffer, Joseph; Moalli, Pamela; Sung, Vivian W; Smith, Ariana L; Rogers, Rebecca; Nolen, Tracy L; Wallace, Dennis; Meikle, Susan F; Gai, Xiaowu; Wolfe, Alan J; Brubaker, Linda

2015-09-01

The purpose of this study was to characterize the urinary microbiota in women who are planning treatment for urgency urinary incontinence and to describe clinical associations with urinary symptoms, urinary tract infection, and treatment outcomes. Catheterized urine samples were collected from multisite randomized trial participants who had no clinical evidence of urinary tract infection; 16S ribosomal RNA gene sequencing was used to dichotomize participants as either DNA sequence-positive or sequence-negative. Associations with demographics, urinary symptoms, urinary tract infection risk, and treatment outcomes were determined. In sequence-positive samples, microbiotas were characterized on the basis of their dominant microorganisms. More than one-half (51.1%; 93/182) of the participants' urine samples were sequence-positive. Sequence-positive participants were younger (55.8 vs 61.3 years old; P = .0007), had a higher body mass index (33.7 vs 30.1 kg/m(2); P = .0009), had a higher mean baseline daily urgency urinary incontinence episodes (5.7 vs 4.2 episodes; P urinary incontinence episodes, -4.4 vs -3.3; P = .0013), and were less likely to experience urinary tract infection (9% vs 27%; P = .0011). In sequence-positive samples, 8 major bacterial clusters were identified; 7 clusters were dominated not only by a single genus, most commonly Lactobacillus (45%) or Gardnerella (17%), but also by other taxa (25%). The remaining cluster had no dominant genus (13%). DNA sequencing confirmed urinary bacterial DNA in many women with urgency urinary incontinence who had no signs of infection. Sequence status was associated with baseline urgency urinary incontinence episodes, treatment response, and posttreatment urinary tract infection risk. Copyright © 2015 Elsevier Inc. All rights reserved.

Low-molecular-weight heparin in the treatment of patients with venous thromboembolism

NARCIS (Netherlands)

tenCate, JW; Buller, HR; Gent, M; Hirsh, J; Prins, MH; Baildon, R; Lensing, AWA; Anderson, DR; vanBeek, EJR; Fiesinger, JN; Tijssen, JGP; vanBarneveld, A; Eimers, LT; Graafsma, YP; Hettiarachchi, R; Hutten, B; Redekop, K; Haley, S; LIberale, L; Finch, T; Whittaker, S; Wilkinson, L; Prandoni, P; Villalta, S; Girolami, B; Bagatella, P; Rossi, L; Girolami, A; Piovella, F; Barone, M; Beltrametti, C; Serafini, S; Siragusa, S; Ascari, E; Kovacs, MJ; Morrow, B; Kovacs, J; Kuijer, PMM; Koopman, MMW; Jagt, H; Weitz, J; Kearon, C; Biagioni, L; Haas, S; Lossner, F; Spengel, FA; Berger, M; Demers, C; Poulin, J; vanderMeer, J; Que, GTH; Smid, WM; Robinson, KS; Boyle, E; Leclerc, [No Value; StJacques, B; Finkenbine, S; Gallus, AS; Cohlan, D; Rich, C; Brandjes, DPM; Hoefnagel, CA; deRijk, M; Turkstra, F; Desjardins, L; CoteDesjardins, J; Couture, L; Ruel, M; Villenueve, J; Geerts, WH; Jay, RM; Code, EKI; Turpie, AGG; Johnson, J; Nguyen, P; Cusson, [No Value; Roy, S; Wells, PS; Bormanis, J; Goudie, D; Cruickshank, M; vonLewinski, M; Monreal, M; Sahuquillo, JC; Lafoz, E; Simonneau, G; Parent, F; Jagot, J; Douketis, JD; Kinnon, K; Ginsberg, JS; BrillEdwards, P; Donovan, D; Ockelford, PA; Kassis, J; Bornais, S; Planchon, B; ElKouri, D; Pistorius, MA; Escribano, M; Garrido, G; Chesterman, CN; Chong, BH; Pritchard, S; Cade, JF; Bynon, T; Stanford, J; Brien, WM; Palmer, B; Faivre, R; Petiteau, B; Manucci, PM; Moia, M; Bucciarelli, P

1997-01-01

Background Low-molecular-weight heparin is known to be safe and effective for the initial Treatment of patients with proximal deep-vein thrombosis. However, its application to patients with pulmonary embolism or previous episodes of thromboembolism has not been studied. Methods We randomly assigned

Urinary tract infection in full-term newborn infants: risk factor analysis

Directory of Open Access Journals (Sweden)

Falcão Mário Cícero

2000-01-01

Full Text Available OBJECTIVE: To analyze the correlation of risk factors to the occurrence of urinary tract infection in full-term newborn infants. PATIENTS AND METHODS: Retrospective study (1997 including full-term infants having a positive urine culture by bag specimen. Urine collection was based on: fever, weight loss > 10% of birth weight, nonspecific symptoms (feeding intolerance, failure to thrive, hypoactivity, debilitate suction, irritability, or renal and urinary tract malformations. In these cases, another urine culture by suprapubic bladder aspiration was collected to confirm the diagnosis. To compare and validate the risk factors in each group, the selected cases were divided into two groups: Group I - positive urine culture by bag specimen collection and negative urine culture by suprapubic aspiration, and Group II - positive urine culture by bag specimen collection and positive urine culture by suprapubic aspiration . RESULTS: Sixty one infants were studied, Group I, n = 42 (68.9% and Group II, n = 19 (31.1%. The selected risk factors (associated infectious diseases, use of broad-spectrum antibiotics, renal and urinary tract malformations, mechanical ventilation, parenteral nutrition and intravascular catheter were more frequent in Group II (p<0.05. Through relative risk analysis, risk factors were, in decreasing importance: parenteral nutrition, intravascular catheter, associated infectious diseases, use of broad-spectrum antibiotics, mechanical ventilation, and renal and urinary tract malformations. CONCLUSION: The results showed that parenteral nutrition, intravascular catheter, and associated infectious diseases contributed to increase the frequency of neonatal urinary tract infection, and in the presence of more than one risk factor, the occurrence of urinary tract infection rose up to 11 times.

Branched chain amino acids maintain the molecular weight of poly(γ-glutamic acid) of Bacillus licheniformis ATCC 9945 during the fermentation.

Science.gov (United States)

Mitsunaga, Hitoshi; Meissner, Lena; Büchs, Jochen; Fukusaki, Eiichiro

2016-10-01

Poly(γ-glutamic acid) mainly produced by Bacillus spp. is an industrially important compound due to several useful features. Among them, molecular weight is an important characteristic affecting on the physical properties such as viscosities and negative charge densities. However, it is difficult to control the molecular size of PGA since it decreases during fermentation. Previous study reported that PGA produced in the media containing different carbon sources such as glucose and glycerol showed differences in molecular weight. Therefore in this study, the effect of carbon source on the PGA molecular weight was examined; with the aim of developing a strategy to maintain the high molecular weight of PGA during fermentation. Our result showed that the weight average molecular weight (Mw) of PGA of Bacillus licheniformis ATCC 9945 cultivated in the media containing PTS-sugars were higher than the medium containing glycerol (non-PTS). The result of metabolome analysis indicated the possibility of CodY (a global regulator protein) activation in the cells cultivated in the media containing PTS-sugars. To mimic this effect, branched-chain amino acids (BCAAs), which are activators of CodY, were added to a medium containing glycerol. As the result, the Mw of PGA in the BCAAs-supplemented media were maintained and high during the early production phase compared to the non BCAAs-supplemented medium. These results indicate that BCAAs can repress the PGA molecular weight reduction during fermentation in B. licheniformis ATCC 9945. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

A study on the effect of the internal exposure to {sup 210}Po on the excretion of urinary proteins in rats

Energy Technology Data Exchange (ETDEWEB)

Sadi, Baki; Li, Chunsheng; Ko, Raymond; Daka, Joseph [Health Canada, National Internal Radiation Assessment Section, Radiation Protection Bureau, Ottawa, ON (Canada); Yusuf, Hamdi [Carleton University, Department of Chemistry, Ottawa, ON (Canada); Wyatt, Heather; Surette, Joel; Priest, Nick [Atomic Energy of Canada Limited, Canadian Nuclear Laboratories, Chalk River, ON (Canada); Hamada, Nobuyuki [Central Research Institute of Electric Power Industry (CRIEPI), Nuclear Technology Research Laboratory, Radiation Safety Research Center, Komae, Tokyo (Japan)

2016-05-15

This study was designed to assess the feasibility of a noninvasive urine specimen for the detection of proteins as indicators of internal exposure to ionizing radiation. Three groups of rats (five in each group) were intravenously injected with 1601 ± 376, 10,846 ± 591 and 48,467 ± 2812 Bq of {sup 210}Po in citrate form. A sham-exposed control group of five rats was intravenously injected with sterile physiological saline. Daily urine samples were collected over 4 days following injection. Purification and pre-concentration of urinary proteins were carried out by ultrafiltration using a 3000 Da molecular weight cutoff membrane filter. The concentration of common urinary proteins, namely albumin, alpha-1-acid glycoprotein, immunoglobulins IgA and IgG, was measured by an enzyme-linked immunosorbent assay. Urinary excretion of albumin decreased dose-dependently (p < 0.05) 96 h post-injection relative to the control group. In contrast, no statistically significant effects were observed for other proteins tested. The dose-dependent decrease in urinary excretion of albumin observed in this study underscores the need for further research, which may lead to the discovery of new biomarkers that would reflect the changes in the primary target organs for deposition of {sup 210}Po. (orig.)

Size and shape of soil humic acids estimated by viscosity and molecular weight.

Science.gov (United States)

Kawahigashi, Masayuki; Sumida, Hiroaki; Yamamoto, Kazuhiko

2005-04-15

Ultrafiltration fractions of three soil humic acids were characterized by viscometry and high performance size-exclusion chromatography (HPSEC) in order to estimate shapes and hydrodynamic sizes. Intrinsic viscosities under given solute/solvent/temperature conditions were obtained by extrapolating the concentration dependence of reduced viscosities to zero concentration. Molecular mass (weight average molecular weight (M (w)) and number average molecular weight (M (n))) and hydrodynamic radius (R(H)) were determined by HPSEC using pullulan as calibrant. Values of M (w) and M (n) ranged from 15 to 118 x 10(3) and from 9 to 50 x 10(3) (g mol(-1)), respectively. Polydispersity, as indicated by M (w)/M (n), increased with increasing filter size from 1.5 to 2.4. The hydrodynamic radii (R(H)) ranged between 2.2 and 6.4 nm. For each humic acid, M (w) and [eta] were related. Mark-Houwink coefficients calculated on the basis of the M (w)-[eta] relationships suggested restricted flexible chains for two of the humic acids and a branched structure for the third humic acid. Those structures probably behave as hydrated sphere colloids in a good solvent. Hydrodynamic radii of fractions calculated from [eta] using Einstein's equation, which is applicable to hydrated sphere colloids, ranged from 2.2 to 7.1 nm. These dimensions are fit to the size of nanospaces on and between clay minerals and micropores in soil particle aggregates. On the other hand, the good agreement of R(H) values obtained by applying Einstein's equation with those directly determined by HPSEC suggests that pullulan is a suitable calibrant for estimation of molecular mass and size of humic acids by HPSEC.

Practical Application of Aptamer-Based Biosensors in Detection of Low Molecular Weight Pollutants in Water Sources

Directory of Open Access Journals (Sweden)

Wei Zhang

2018-02-01

Full Text Available Water pollution has become one of the leading causes of human health problems. Low molecular weight pollutants, even at trace concentrations in water sources, have aroused global attention due to their toxicity after long-time exposure. There is an increased demand for appropriate methods to detect these pollutants in aquatic systems. Aptamers, single-stranded DNA or RNA, have high affinity and specificity to each of their target molecule, similar to antigen-antibody interaction. Aptamers can be selected using a method called Systematic Evolution of Ligands by EXponential enrichment (SELEX. Recent years we have witnessed great progress in developing aptamer selection and aptamer-based sensors for low molecular weight pollutants in water sources, such as tap water, seawater, lake water, river water, as well as wastewater and its effluents. This review provides an overview of aptamer-based methods as a novel approach for detecting low molecular weight pollutants in water sources.

Simulated dynamic response of a multi-stage compressor with variable molecular weight flow medium

Science.gov (United States)

Babcock, Dale A.

1995-01-01

A mathematical model of a multi-stage compressor with variable molecular weight flow medium is derived. The modeled system consists of a five stage, six cylinder, double acting, piston type compressor. Each stage is followed by a water cooled heat exchanger which serves to transfer the heat of compression from the gas. A high molecular weight gas (CFC-12) mixed with air in varying proportions is introduced to the suction of the compressor. Condensation of the heavy gas may occur in the upper stage heat exchangers. The state equations for the system are integrated using the Advanced Continuous Simulation Language (ACSL) for determining the system's dynamic and steady state characteristics under varying operating conditions.

Low molecular weight components in an aquatic humic substance as characterized by membrane dialysis and orbitrap mass spectrometry.

Science.gov (United States)

Remucal, Christina K; Cory, Rose M; Sander, Michael; McNeill, Kristopher

2012-09-04

Suwannee River fulvic acid (SRFA) was dialyzed through a 100-500 molecular weight cutoff dialysis membrane, and the dialysate and retentate were analyzed by UV-visible absorption and high-resolution Orbitrap mass spectrometry (MS). A significant fraction (36% based on dissolved organic carbon) of SRFA passed through the dialysis membrane. The fraction of SRFA in the dialysate had a different UV-visible absorption spectrum and was enriched in low molecular weight molecules with a more aliphatic composition relative to the initial SRFA solution. Comparison of the SRFA spectra collected by Orbitrap MS and Fourier transform ion cyclotron resonance MS (FT-ICR MS) demonstrated that the mass accuracy of the Orbitrap MS is sufficient for determination of unique molecular formulas of compounds with masses masses detected by Orbitrap MS were found in the 100-200 Da mass range. Many of these low molecular masses corresponded to molecular formulas of previously identified compounds in organic matter, lignin, and plants, and the use of the standard addition method provided an upper concentration estimate of selected target compounds in SRFA. Collectively, these results provide evidence that SRFA contains low molecular weight components that are present individually or in loosely bound assemblies.

Managing cancer-related venous thromboembolic disease: low-molecular-weight heparins and beyond.

Science.gov (United States)

O'Connell, Casey L; Liebman, Howard A

2008-12-01

Venous thromboembolism is a major contributor to the morbidity and mortality of patients with cancer. For patients undergoing cancer surgery, several trials support the safety and efficacy of unfractionated heparin and of low-molecular-weight heparin for the prevention of venous thromboembolism, while data regarding the efficacy and safety of these agents in the setting of medical hospitalization is less definitive and must be extracted from trials including noncancer patients with different thrombotic risk factors. Randomized clinical studies confirm that patients with cancer who develop venous thromboembolism have superior outcomes when treated with long-term low-molecular-weight heparin as compared with warfarin. Novel anticoagulants that are orally bioavailable and function by directly inhibiting factor Xa or thrombin are entering the market. To date, data regarding the efficacy and safety of these novel anticoagulants as venous thromboembolism prophylaxis and treatment in cancer patients are not available and must be extracted from larger trials with heterogeneous patient populations.

Prevalence of urinary incontinence and pelvic floor muscle dysfunction in primiparae two years after cesarean section: cross-sectional study.

Science.gov (United States)

Barbosa, Angélica Mércia Pascon; Marini, Gabriela; Piculo, Fernanda; Rudge, Cibele Vieira Cunha; Calderon, Iracema Mattos Paranhos; Rudge, Marilza Vieira Cunha

2013-01-01

There is uncertainty in the literature regarding the theory that obstetric events and pelvic floor injuries give rise to lower risk of subsequent urinary incontinence among women delivering via cesarean section than among women delivering vaginally. The objective of this study was to assess the two-year postpartum prevalence of urinary incontinence and pelvic floor muscle dysfunction and the factors responsible for them. Cross-sectional study, conducted in a public university. 220 women who had undergone elective cesarean section or vaginal childbirth two years earlier were selected. Their urinary incontinence symptoms were investigated, and their pelvic floor muscle dysfunction was assessed using digital palpation and a perineometer. The two-year urinary incontinence prevalences following vaginal childbirth and cesarean section were 17% and 18.9%, respectively. The only risk factor for pelvic floor muscle dysfunction was weight gain during pregnancy. Body mass index less than 25 kg/m 2 and normal pelvic floor muscle function protected against urinary incontinence. Gestational urinary incontinence increased the risk of two-year postpartum urinary incontinence. Gestational urinary incontinence was a crucial precursor of postpartum urinary incontinence. Weight gain during pregnancy increased the subsequent risk of pelvic floor muscle dysfunction, and elective cesarean section did not prevent urinary incontinence.

Prevalence of urinary incontinence and pelvic floor muscle dysfunction in primiparae two years after cesarean section: cross-sectional study

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Angélica Mércia Pascon Barbosa

Full Text Available CONTEXT AND OBJECTIVE There is uncertainty in the literature regarding the theory that obstetric events and pelvic floor injuries give rise to lower risk of subsequent urinary incontinence among women delivering via cesarean section than among women delivering vaginally. The objective of this study was to assess the two-year postpartum prevalence of urinary incontinence and pelvic floor muscle dysfunction and the factors responsible for them. DESIGN AND SETTING Cross-sectional study, conducted in a public university. METHODS 220 women who had undergone elective cesarean section or vaginal childbirth two years earlier were selected. Their urinary incontinence symptoms were investigated, and their pelvic floor muscle dysfunction was assessed using digital palpation and a perineometer. RESULTS The two-year urinary incontinence prevalences following vaginal childbirth and cesarean section were 17% and 18.9%, respectively. The only risk factor for pelvic floor muscle dysfunction was weight gain during pregnancy. Body mass index less than 25 kg/m 2 and normal pelvic floor muscle function protected against urinary incontinence. Gestational urinary incontinence increased the risk of two-year postpartum urinary incontinence. CONCLUSION Gestational urinary incontinence was a crucial precursor of postpartum urinary incontinence. Weight gain during pregnancy increased the subsequent risk of pelvic floor muscle dysfunction, and elective cesarean section did not prevent urinary incontinence.

Validity and reliability of parental report of frequency, severity and risk factors of urinary tract infection and urinary incontinence in children.

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Sureshkumar, Premala; Cumming, Robert G; Craig, Jonathan C

2006-06-01

We describe the validity and reliability of a questionnaire designed to determine frequency, severity and risk factors of urinary tract infection and daytime urinary incontinence in primary school-age children. Based on published validated questionnaires and advice from content experts, a questionnaire was developed and piloted in children attending outpatient clinics. Construct validity for parent report of frequency and severity of daytime urinary incontinence was tested by comparison with a daily accident diary in 52 primary school children, and criterion validity of parent report for UTI was verified by comparison with the reference standard (urine culture) in 100 primary school children. Test-retest reliability of the questionnaire was assessed in 106 children from primary schools. There was excellent agreement between the questionnaire and accident diary in severity (weighted kappa 0.94, 95% confidence intervals 0.85 to 1.03) and frequency of daytime urinary incontinence (0.88, 0.7 to 1.0). Parents reported urinary tract infection in 15% of children, compared to a positive urine culture in 8% (sensitivity 100% and specificity 68.5%). Test-retest reliability of the questionnaire was excellent (mean k 0.78, range 0.61 to 1.00). Parents overreport UTI by about 2-fold but can recall frequency and severity of daytime urinary incontinence well during a 3-month period. The developed questionnaire is a valid tool to estimate frequency, severity and risk factors of daytime urinary incontinence and UTI in primary school children.

Effect of thermal treatment on potato starch evidenced by EPR, XRD and molecular weight distribution.

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Bidzińska, Ewa; Michalec, Marek; Pawcenis, Dominika

2015-12-01

Effect of heating of the potato starch on damages of its structure was investigated by quantitative electron paramagnetic resonance (EPR) spectroscopy, X-ray diffraction and determination of the molecular weight distribution. The measurements were performed in the temperature range commonly used for starch modifications optimizing properties important for industrial applications. Upon thermal treatment, because of breaking of the polymer chains, diminishing of the average molecular weights occurred, which significantly influences generation of radicals, evidenced by EPR. For the relatively mild conditions, with heating parameters not exceeding temperature 230 °C and time of heating equal to 30 min a moderate changes of both the number of thermally generated radicals and the mean molecular weight of the starch were observed. After more drastic thermal treatment (e.g. 2 h at 230 °C), a rapid increase in the radical amount occurred, which was accompanied by significant reduction of the starch molecular size and crystallinity. Experimentally established threshold values of heating parameters should not be exceeded in order to avoid excessive damages of the starch structure accompanied by the formation of the redundant amount of radicals. This requirement is important for industrial applications, because significant destruction of the starch matrix might annihilate the positive influence of the previously performed intentional starch modification. Copyright © 2015 John Wiley & Sons, Ltd.

Isotope chemistry and molecular structure. The WINIMAX weighting factor

International Nuclear Information System (INIS)

Lee, M.W.; Bigeleisen, J.

1979-01-01

The modulating coefficients for the finite polynomial expansion of the logarithm of the reduced partition function, lnb (u), of a harmonic oscillator have been obtained for the range of 0 6 . It is shown that this weighting function is near optimum to insure minimum amplitudes of oscillation in the expansion of lnb (u) as a function of the order of the expansion and to include most of the important molecular structure information contained in the moments of the eigenvalues. Beyond Σu/sub i/ 6 , there is little new structural information

Prophylaxis of postoperative thromboembolism with low molecular weight heparins

DEFF Research Database (Denmark)

Jørgensen, L N; Wille-Jørgensen, P; Hauch, O

1993-01-01

To evaluate the thromboprophylactic use of low molecular weight heparins (LMWHs), publications from 27 orthopaedic trials and 35 studies of patients undergoing general or gynaecological surgery were scrutinized and subjected to a partial meta-analysis. In orthopaedic surgery, LMWHs were superior...... to placebo or dextran and at least as efficient as unfractionated heparin in the prevention of deep vein thrombosis (DVT). Compared with unfractionated heparin, one of the LMWH preparations significantly reduced the total incidence of DVT. The rate of non-fatal pulmonary embolism was 0.49 per cent...

The relative role of serum albumin and urinary creatinine as ...

African Journals Online (AJOL)

Their weight, Body mass index, serum albumin and 24-hour urinary creatinine were determined before treatment, at the end of the 1st, 2nd, 4th and 6th month of treatment. Using ANOVA, the mean values of the weight, BIM and serum albumin were analysed with further analysis paired student T- test of the pre-treatment ...

Methanol-induced chain termination in poly(3-hydroxybutyrate) biopolymers: molecular weight control

Science.gov (United States)

A systematic study was performed to demonstrate the impact of methanol (MeOH) on poly(3-hydroxybutyrate) (PHB) synthesis and molecular weight (MW) control. Glycerine (init. conc. = 1.0%; w/v), was used as the primary carbon source in batch-culture fermentations with varying concentrations (0 to 0.85...

Low molecular weight chemical-induced occupational asthma : The focus on alveolar macrophages

NARCIS (Netherlands)

Valstar, Dingena Labine

2004-01-01

Asthma is a very common disorder and its prevalence has increased over the past two to three decades. The proportion of cases attributable to occupational exposure at the workplace is estimated at ~10% of adult-onset asthma. Most cases of occupational asthma are caused by low molecular weight

A study on the effect of the internal exposure to "2"1"0Po on the excretion of urinary proteins in rats

International Nuclear Information System (INIS)

Sadi, Baki; Li, Chunsheng; Ko, Raymond; Daka, Joseph; Yusuf, Hamdi; Wyatt, Heather; Surette, Joel; Priest, Nick; Hamada, Nobuyuki

2016-01-01

This study was designed to assess the feasibility of a noninvasive urine specimen for the detection of proteins as indicators of internal exposure to ionizing radiation. Three groups of rats (five in each group) were intravenously injected with 1601 ± 376, 10,846 ± 591 and 48,467 ± 2812 Bq of "2"1"0Po in citrate form. A sham-exposed control group of five rats was intravenously injected with sterile physiological saline. Daily urine samples were collected over 4 days following injection. Purification and pre-concentration of urinary proteins were carried out by ultrafiltration using a 3000 Da molecular weight cutoff membrane filter. The concentration of common urinary proteins, namely albumin, alpha-1-acid glycoprotein, immunoglobulins IgA and IgG, was measured by an enzyme-linked immunosorbent assay. Urinary excretion of albumin decreased dose-dependently (p < 0.05) 96 h post-injection relative to the control group. In contrast, no statistically significant effects were observed for other proteins tested. The dose-dependent decrease in urinary excretion of albumin observed in this study underscores the need for further research, which may lead to the discovery of new biomarkers that would reflect the changes in the primary target organs for deposition of "2"1"0Po. (orig.)

Use of Kinematic Viscosity Data for the Evaluation of the Molecular Weight of Petroleum Oils

Science.gov (United States)

Maroto, J. A.; Quesada-Perez, M.; Ortiz-Hernandez, A. J.

2010-01-01

A new laboratory procedure for the evaluation of the mean molecular weight (mean relative molecular mass) of petroleum oils with high accuracy is described. The density and dynamic viscosity of three commercial petroleum oils are measured at different temperatures. These experimental data are used to calculate the kinematic viscosity as a function…

[Analysis of risk factors about stress urinary incontinence in female].

Science.gov (United States)

Song, Yan-feng; Lin, Jian; Li, Ya-qin; He, Xiao-yu; Xu, Bo; Hao, Lan; Song, Jian

2003-12-01

The aim was to assess the prevalence of stress urinary incontinence (SUI) in community dwelling women and to assess the relationship between the various risk factors and this disease. Selecting the community of Gulou at random and sending questionnaires to 6,066 women who living there. The questionnaire was designed to investigate the lower urinary tract symptoms, especially urinary incontinence. The questionnaire included some questions such as: age, weight, occupation, the level of education, menopause pregnancy and delivery, delivery through vagina or by cesarean section, the maximum body weight of fetus, chronic disease (hypertension, diabetes mellitus, cough, constipation), operation in abdomen and pelvis, the behaviour of life (smoking, alcohol abuse, exercise), the prevalence and frequency of urinary incontinence, the quality of life and the recognition of this disease. The collecting rate was 92.1% (5,587/6,066). The prevalence of urinary incontinence was 18.1% and the prevalence of SUI was 8.8%. Age (OR: 1.010, 95% CI: 1.001 - 1.025), higher body mass index (OR: 1.092, 95% CI: 1.054 - 1.132), hypertension (OR: 2.342, 95% CI: 1.026 - 5.349), constipation (OR: 1.448, 95% CI: 1.216 - 1.725), multiple abortion (OR: 1.306, 95% CI: 1.113 - 1.533), multipara (OR: 1.205, 95% CI: 1.009 - 1.440), using abdominal pressure in laboring (OR: 1.684, 95% CI: 1.140 - 2.489), straight cutting of perineum (OR: 2.244, 95% CI: 1.162 - 4.334), perineum tear (OR: 2.576, 95% CI: 1.724 - 3.851), infection of perineal incision (OR: 5.988, 95% CI: 1.936 - 18.616) were risk factors of SUI in women. Many risk factors can cause urinary incontinence, among them age, pregnancy and childbirth are most important ones.

Purification of two high molecular weight proteases from rabbit reticulocyte lysate

International Nuclear Information System (INIS)

Hough, R.; Pratt, G.; Rechsteiner, M.

1987-01-01

The authors have purified two large proteases from rabbit reticulocyte lysate. The enzymes are so similar in their chromatographic behavior that each is the only significant contaminant of the other during the final stages of purification. At pH 7.8, both hydrolyze 125 I-α-casein and 4-methylcoumaryl-7-amide (MCA) derivatives with tyrosine, phenylalanine or arginine at the P 1 position. The larger, ATP-dependent enzyme degrades ubiquitin-lysozyme conjugates, but it does not degrade unmodified lysozyme. Hydrolysis of Suc-Leu-Leu-Val-Tyr-MCA by this enzyme is also stimulated two-fold in the presence of ATP. The protease has a molecular weight of 950,000 based on sedimentation, gel filtration and non-denaturing PAGE. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the protease is composed of a number of subunits with molecular masses between 32 and 110 kDa. Densitometric analysis showed equivalent amounts of the two larger chains, and the presence of one copy of each in the native enzyme would be consistent with an M/sub r/ of 950,000. The smaller protease has a molecular weight of 700,000 and is composed of 8 to 10 subunits ranging from 21,000 to 32,000. It cleaves ubiquitin-lysozyme conjugates only slightly, and hydrolysis of conjugates or fluorogenic peptide substrates is not stimulated by ATP. This protease appears similar, if not identical, to the multicatalytic protease complex first purified by Wilk and Orlowski

Early weight changes after birth and serum high-molecular-weight adiponectin level in preterm infants.

Science.gov (United States)

Yoshida, Tomohide; Nagasaki, Hiraku; Asato, Yoshihide; Ohta, Takao

2011-12-01

Extra-uterine growth retardation (EUGR) is associated with an increased risk for cardiometabolic diseases later in life. The aim of the present study was to examine the relationship between early weight change after birth in preterm infants and adiponectin (adn) multimeric complexes. Subjects included 28 preterm infants born between weeks 24 and 33 of gestation. Serum adn multimeric complexes and the anthropometric parameters were measured in preterm infants at birth and at corrected term. Bodyweight (BW) decreased during the first week of life, with birthweight restored at approximately 19 days after birth. Nineteen of the subjects had EUGR at corrected term. Total (T)-adn, high-molecular-weight (H)-adn, and the ratio of H-adn to T-adn (H/T-adn) were significantly elevated at corrected term than at birth. Postmenstrual age, birthweight, birth length and lowest BW after birth were positively correlated with H-adn and H/T-adn. Weight reduction after birth was negatively correlated with H-adn. Age to restore birthweight was negatively correlated with T-adn, H-adn and H/T-adn. Stepwise multiple regression analysis indicated age to restore birthweight as the major predictor of T-adn and H-adn. Early weight changes after birth may alter serum adn level in preterm infants at corrected term. The appropriate nutritional support in the early postnatal period could reduce the prevalence of EUGR and the future risk for cardiometabolic diseases. © 2011 The Authors. Pediatrics International © 2011 Japan Pediatric Society.

NGS Reveals Molecular Pathways Affected by Obesity and Weight Loss-Related Changes in miRNA Levels in Adipose Tissue

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Alina Kuryłowicz

2017-12-01

Full Text Available Both obesity and weight loss may cause molecular changes in adipose tissue. This study aimed to characterize changes in adipose tissue miRNome in order to identify molecular pathways affected by obesity and weight changes. Next generation sequencing (NGS was applied to identify microRNAs (miRNAs differentially expressed in 47 samples of visceral (VAT and subcutaneous (SAT adipose tissues from normal-weight (N, obese (O and obese after surgery-induced weight loss (PO individuals. Subsequently miRNA expression was validated by real-time PCR in 197 adipose tissues and bioinformatics analysis performed to identify molecular pathways affected by obesity-related changes in miRNA expression. NGS identified 344 miRNAs expressed in adipose tissues with ≥5 reads per million. Using >2 and <−2 fold change as cut-offs we showed that the expression of 54 miRNAs differed significantly between VAT-O and SAT-O. Equally, between SAT-O and SAT-N, the expression of 20 miRNAs differed significantly, between SAT-PO and SAT-N the expression of 79 miRNAs differed significantly, and between SAT-PO and SAT-O, the expression of 61 miRNAs differed significantly. Ontological analyses disclosed several molecular pathways regulated by these miRNAs in adipose tissue. NGS-based miRNome analysis characterized changes of the miRNA profile of adipose tissue, which are associated with changes of weight possibly responsible for a differential regulation of molecular pathways in adipose tissue when the individual is obese and after the individual has lost weight.

Insights into cellular and molecular basis for urinary tract infection in autosomal-dominant polycystic kidney disease.

Science.gov (United States)

Gao, Chao; Zhang, Long; Zhang, Ye; Wallace, Darren P; Lopez-Soler, Reynold I; Higgins, Paul J; Zhang, Wenzheng

2017-11-01

Urinary tract infection (UTI) is a broad term referring to an infection of the kidneys, ureters, bladder, and/or urethra. Because of its prevalence, frequent recurrence, and rising resistance to antibiotics, UTI has become a challenge in clinical practice. Autosomal-dominant polycystic kidney disease (ADPKD) is the most common monogenic disorder of the kidney and is characterized by the growth of fluid-filled cysts in both kidneys. Progressive cystic enlargement, inflammation, and interstitial fibrosis result in nephron loss with subsequent decline in kidney function. ADPKD patients frequently develop UTI; however, the cellular and molecular mechanisms responsible for the high UTI incidence in ADPKD patients remain virtually unaddressed. Emerging evidence suggests that α-intercalated cells (α-ICs) of the collecting ducts function in the innate immune defense against UTI. α-ICs inhibit bacterial growth by acidifying urine and secreting neutrophil gelatinase-associated lipocalin (NGAL) that chelates siderophore-containing iron. It is necessary to determine, therefore, if ADPKD patients with recurrent UTI have a reduced number and/or impaired function of α-ICs. Identification of the underlying cellular and molecular mechanisms may lead to the development of novel strategies to reduce UTI in ADPKD. Copyright © 2017 the American Physiological Society.

Temperature dependence of viscoelasticity of crystalline cellulose with different molecular weights added to silicone elastomer

Science.gov (United States)

Sugino, Naoto; Nakajima, Shinya; Kameda, Takao; Takei, Satoshi; Hanabata, Makoto

2017-08-01

Silicone elastomers ( polydimethylsiloxane _ PDMS) are widely used in the field of imprint lithography and microcontactprinting (μCP). When performing microcontactprinting, the mechanical properties of the PCMS as a base material have a great influence on the performance of the device. Cellulose nanofibers having features of high strength, high elasticity and low coefficient of linear expansion have attracted attention in recent years due to their characteristics. Therefore, three types of crystalline cellulose having different molecular weights were added to PDMS to prepare a composite material, and dynamic viscoelasticity was measured using a rheometer. The PDMS with the highest molecular weight crystalline cellulose added exhibited smaller storage modulus than PDMS with other molecular weight added in all temperature ranges. Furthermore, when comparing PDMS to which crystalline cellulose was added and PDMS which is not added, the storage modulus of PDMS to which cellulose was added in the low temperature region was higher than that of PDMS to which it was not added, but it was reversed in the high temperature region It was a result. When used in a low temperature range (less than 150 ° C.), it can be said that cellulose can function as a reinforcing material for PDMS.

[Crosslinking sodium hyaluronate gel with different ratio of molecular weight for subcutaneous injection: animal experimental study and clinical trials subcutaneous injection].

Science.gov (United States)

Ran, Weizhi; Wang, Xiaoli; Hu, Yuefei; Gao, Songying; Yang, Yahong; Sun, Jian; Sun, Shuming; Liu, Zhongmei; Wang, Jiangling

2015-05-01

To investigate the biocompatibility and degradation rate of crosslinking sodium hyaluronate gel with different ratio of molecular weight, so as to choose the effective, safe and totally degraded hyaluronate gel for aesthetic injection. (1) Compound colloid was formed by cross-linking the divinyl sulphone and sodium hyaluronate with different molecular weight (4 x 10(5), 8 x 10(5), 10 x 10(5), 12 x 10(5)). (2) Healthy level KM mice was randomly divided into two groups to receive hyaluronic acid gel or liquid injection. Each group was subdivided into three subgroup to receive hyaluronic acid with different molecular weight. The biocompatibility and degradation rate, of hyaluronate were observed at 7, 90, 180 days after injection. At the same time, different molecular weight of sodium hyaluronate gel is sealed or exposed respectively under the low temperature preservation to observe its natural degradation rate. (3) The most stable colloid was selected as aesthetic injector for volunteers to observe the aesthetic effect. The sodium hyaluronate gel with molecular of 4 x 10(5) was completely degraded 90 days later. The sodium hyaluronate gel with molecular of 8 x 10(5) was completely degraded 180 days later. The sodium hyaluronate gel with molecular of 10 x 10(5) was degraded to 90.0% after 180 days. The sodium hyaluronate liquid can be degraded completely within 7 days. The colloid could be kept for at least 12 months when sealed under low temperature, but was totally degraded when exposed for I d. Sodium hyaluronate gel with molecular 10 x 10(5) was confirmed to be kept for at least 6 months in animal experiment and clinical trials. Under the same condition of material ratio, the higher the molecular weight is, the lower the degradation rate is. But the liquidity of gel is not good for injection when molecular weight is too large. It suggests that Sodium hyaluronate gel with molecular 10 x 10(5) maybe the best choice in cosmetic injections.

Removal of Anabaena spiroides by potassium permanganate pre-oxidation: effect on photosynthetic capacity and molecular weight distribution.

Science.gov (United States)

Qiao, Junlian; Zhang, Xiaodong; Lv, Liping

2017-11-01

Bench scale tests were conducted to investigate the effect of potassium permanganate pre-oxidation on the photosynthetic activity and molecular weight distribution of Anabaena spiroides. Different concentrations of potassium permanganate were added into the suspension of Anabaena spiroides, one of the dominant algae in water bloom, and after pre-oxidation of permanganate for 1 h, the results show that the removal rate significantly increases by 33.99~36.35% compared to direct coagulation. Then, the algal characteristics, including photosynthetic ability, the changes in extracellular organic matter three-dimensional fluorescence, and the distribution of molecular weight were conducted and the results show that along with increasing concentration of potassium permanganate, the photosynthetic ability of algae decreases, more extracellular organic matter is secreted, and large molecular weight matter (humic-like and fulvic-like substances) are generated. Therefore, this study demonstrates that potassium permanganate could be used in addressing the algae-rich water.

Release of low molecular weight silicones and platinum from silicone breast implants.

Science.gov (United States)

Lykissa, E D; Kala, S V; Hurley, J B; Lebovitz, R M

1997-12-01

We have conducted a series of studies addressing the chemical composition of silicone gels from breast implants as well as the diffusion of low molecular weight silicones (LM-silicones) and heavy metals from intact implants into various surrounding media, namely, lipid-rich medium (soy oil), aqueous tissue culture medium (modified Dulbecco's medium, DMEM), or an emulsion consisting of DMEM plus 10% soy oil. LM-silicones in both implants and surrounding media were detected and quantitated using gas chromatography (GC) coupled with atomic emission (GC-AED) as well as mass spectrometric (GC/MS) detectors, which can detect silicones in the nanogram range. Platinum, a catalyst used in the preparation of silicone gels, was detected and quantitated using inductive argon-coupled plasma/mass spectrometry (ICP-MS), which can detect platinum in the parts per trillion range. Our results indicate that GC-detectable low molecular weight silicones contribute approximately 1-2% to the total gel mass and consist predominantly of cyclic and linear poly-(dimethylsiloxanes) ranging from 3 to 20 siloxane [(CH3)2-Si-O] units (molecular weight 200-1500). Platinum can be detected in implant gels at levels of approximately 700 micrograms/kg by ICP-MS. The major component of implant gels appears to be high molecular weight silicone polymers (HM-silicones) too large to be detected by GC. However, these HM-silicones can be converted almost quantitatively (80% by mass) to LM-silicones by heating implant gels at 150-180 degrees C for several hours. We also studied the rates at which LM-silicones and platinum leak through the intact implant outer shell into the surrounding media under a variety of conditions. Leakage of silicones was greatest when the surrounding medium was lipid-rich, and up to 10 mg/day LM-silicones was observed to diffuse into a lipid-rich medium per 250 g of implant at 37 degrees C. This rate of leakage was maintained over a 7-day experimental period. Similarly, platinum was

Reversible, high molecular weight palladium and platinum coordination polymers based on phosphorus ligands

NARCIS (Netherlands)

Paulusse, J.M.J.; Huijbers, J.P.J.; Sijbesma, R.P.

2005-01-01

A general strategy for the preparation and characterization of high molecular weight coordination polymers based on bifunctional phosphorus ligands and palladium or platinum dichloride is described. Metal-to-ligand stoichiometry is of key importance for the formation of linear coordination polymers

Reversible, High Molecular Weight Palladium and Platinum Coordination Polymers Based on Phosphorus Ligands

NARCIS (Netherlands)

Paulusse, Jos Marie Johannes; Huijbers, Jeroen P.J.; Sijbesma, Rint P.

2005-01-01

A general strategy for the preparation and characterization of high molecular weight coordination polymers based on bifunctional phosphorus ligands and palladium or platinum dichloride is described. Metal-to-ligand stoichiometry is of key importance for the formation of linear coordination polymers

Maternal urinary bisphenol A levels and infant low birth weight: A nested case-control study of the Health Baby Cohort in China.

Science.gov (United States)

Huo, Wenqian; Xia, Wei; Wan, Yanjian; Zhang, Bin; Zhou, Aifen; Zhang, Yiming; Huang, Kai; Zhu, Yingshuang; Wu, Chuansha; Peng, Yang; Jiang, Minmin; Hu, Jie; Chang, Huailong; Xu, Bing; Li, Yuanyuan; Xu, Shunqing

2015-12-01

Exposure to bisphenol A (BPA), a known endocrine disruptor, has been demonstrated to affect fetal development in animal studies, but findings in human studies have been inconsistent. We investigated whether maternal exposure to BPA during pregnancy is associated with an increased risk of infant low birth weight (LBW). A total 452 mother-infant pairs (113 LBW cases and 339 matched controls) were selected from the participants enrolled in the prospective Health Baby Cohort (HBC) in Wuhan city, China, during 2012-2014. BPA concentrations were measured in maternal urine samples collected at delivery, and the information of birth outcomes was retrieved from the medical records. A conditional logistic regression was used to evaluate the relationship between urinary BPA levels and LBW. Mothers with LBW infants had significantly higher urinary BPA levels (median: 4.70μg/L) than the control mothers (median: 2.25μg/L) (p<0.05). Increased risk of LBW was associated with higher maternal urinary levels of BPA [adjusted odds ratio (OR)=3.13 for the medium tertile, 95% confidence interval (CI): 1.21, 8.08; adjusted OR=2.49 for the highest tertile, 95% CI: 0.98, 6.36]. The association was more pronounced among female infants than among male infants, with a statistical evidence of heterogeneity in risk (p=0.03). Prenatal exposure to higher levels of BPA may potentially increase the risk of delivering LBW infants, especially for female infants. This is the first case-control study to examine the association in China. Copyright © 2015 Elsevier Ltd. All rights reserved.

Age and prostate volume are risk factors for transient urinary incontinence after transurethral enucleation with bipolar for benign prostatic hyperplasia.

Science.gov (United States)

Hirasawa, Yosuke; Kato, Yuji; Fujita, Kiichiro

2018-01-01

To investigate the predictive factors for transient urinary incontinence after transurethral enucleation with bipolar. We retrospectively analyzed the data of 584 patients who underwent transurethral enucleation with bipolar between December 2011 and September 2016 operated by a single surgeon. Urinary incontinence after transurethral enucleation with bipolar was defined as involuntary leakage of urine that required the use of pads. It was evaluated at 1 week, and 1, 3, 6, 12 and 24 months after transurethral enucleation with bipolar. We defined transient urinary incontinence as urinary incontinence persisting up to 1 month after transurethral enucleation with bipolar. Based on independent risk factors identified by a multivariate stepwise logistic regression analysis, a nomogram to predict transient urinary incontinence was developed. Of the 584 patients, 17.3%, 13.5%, 3.1%, 0.41%, and 0% patients had urinary incontinence at 1 week, 1, 3, 6 and 12 months after transurethral enucleation with bipolar, respectively. The mean (±standard error) age was 69.6 ± 0.26 years, estimated prostate volume was 54.7 ± 0.91 cm 3 , operative time was 58.0 ± 1.1 min and the prostate specimen weight was 30.6 ± 0.69 g. On univariate analysis, age, prostate volume estimated by transrectal ultrasonography, prostate-specific antigen, prostate specimen weight, operative time, prostate specimen weight/prostate volume and prostate specimen weight/operative time were significant predictive factors for transient urinary incontinence after transurethral enucleation with bipolar. On multivariate analysis, age (hazard ratio 1.07, P-value = 0.0034) and prostate volume (hazard ratio 1.03, P-value bipolar. Age and prostate volume estimated by transrectal ultrasonography seem to represent significant independent risk factors for transient urinary incontinence after transurethral enucleation with bipolar. This should be well discussed with the patient before surgery. © 2017 The Japanese

Effect of Molecular Weight and Molar Ratio of Dextran on Self-Assembly of Dextran Stearate Polymeric Micelles as Nanocarriers for Etoposide

Directory of Open Access Journals (Sweden)

Jaleh Varshosaz

2012-01-01

Full Text Available Amphiphilic polymer surfactants are composed of hydrophilic and hydrophobic polymers and are widely used in targeted drug delivery. The purpose of this study was the evaluation of the effect of molecular weight and molar ratio of dextran on physicochemical properties of dextran stearate polymeric micelles. Dextran stearate was synthesized by acylation of dextran with stearoyl chloride. Etoposide loaded polymeric micelles were prepared by dialysis method. The resulting micelles were evaluated for particle size, zeta potential, critical micelle concentration (CMC, drug loading capacity, and release efficiency. Cytotoxicity and cellular uptake of micelles were studied in CT-26 colorectal carcinoma cell line. Molecular weight and molar ratio of dextran-stearate were impressive on zeta potential, CMC, drug loading capacity, and release efficiency. Unlike polymer molecular weight, molar ratio of stearate had a significant effect on cytotoxicity and particle size of etoposide loaded micelles. Although molecular weight of dextran had no significant effect on cytotoxicity of micelles on CT-26 cells, it had drastic attributes for stability of polymeric micelles. Consequently, both variables of molecular weight of dextran and molar ratio of stearate should be taken into account to have a stable and effective micelle of dextran-stearate.

Removal of high-molecular weight polycyclic aromatic hydrocarbons

Directory of Open Access Journals (Sweden)

Ulrich Vasconcelos

2011-01-01

Full Text Available Alternatives for the removal of high-molecular weight polycyclic aromatic hydrocarbons (HWM-PAH from soil were tested by adding fertilizer or glycerol, as well as the combination of both. Experiments were carried out for 60 days in reactors containing a HWM-PAH-contaminated soil (8030 μg kg-1, accompanied by pH monitoring, humidity control and quantification of total heterotrophic bacteria and total fungus. Fertilizer addition removed 41.6% of HWM-PAH. Fertilizer and glycerol in combination removed 46.2%. When glycerol was added individually, degradation reached 50.4%. Glycerol also promoted the increase of degradation rate during the first 30 days suggesting the HMW-PAH removal occurred through cometabolic pathways.

MR imaging of urinary bladder cancer for T-staging: a review and a pictorial essay of diffusion-weighted imaging.

Science.gov (United States)

Takeuchi, Mitsuru; Sasaki, Shigeru; Naiki, Taku; Kawai, Noriyasu; Kohri, Kenjiro; Hara, Masaki; Shibamoto, Yuta

2013-12-01

Treatment decisions for bladder cancer patients are mainly based on the depth of bladder wall invasion by the tumor. In this article, we review the conventional MRI and exhibit a recently emerged diffusion-weighted imaging (DWI) of urinary bladder cancer for T-staging. We discuss limitations of conventional MRI, scanning protocols of DWI, normal pelvic findings on DWI, determination of T-stage using DWI, and pitfalls of DWI. DWI provides high contrast between bladder cancer and background tissue because the cancer shows markedly high SI. DWI has high sensitivity for detecting the stalk seen in stage Ta or T1. An inflammatory change or fibrosis surrounding the tumor mimics the invasion of bladder cancer on T2-weighted imaging or enhanced MRI and could lead to over-staging, but DWI could differentiate them clearly because these benign changes do not show high SI on DWI. DWI is also useful for detecting ureteral, urethral, and prostatic extension by means of the urethra. DWI provides more accurate information on the extent of bladder cancer and contributes to determination of the treatment strategy. Copyright © 2013 Wiley Periodicals, Inc.

Retardative chain transfer in free radical free-radical polymerisations of vinyl neo-decanoate in low molecular weight polyisoprene and toluene

NARCIS (Netherlands)

Monteiro, M.J.; Subramaniam, N.; Taylor, J.R.; Pham, B.T.T.; Tonge, M.P.; Gilbert, R.G.

2001-01-01

The kinetics of free-radical polymerisation of vinyl neo-decanoate (VneoD) and the molecular weight distributions (MWDs) of the polymers formed in the presence and absence of low molecular weight polyisoprene at 50°C under a variety of conditions were investigated. The bulk reaction was successfully

Urinary tract infection during pregnancy: current concepts on a common multifaceted problem.

Science.gov (United States)

Kalinderi, Kallirhoe; Delkos, Dimitrios; Kalinderis, Michail; Athanasiadis, Apostolos; Kalogiannidis, Ioannis

2018-02-06

Urinary tract infections (UTIs) are the most common bacterial infection in pregnancy, increasing the risk of maternal and neonatal morbidity and mortality. Urinary tract infections may present as asymptomatic bacteriuria, acute cystitis or pyelonephritis. Escherichia coli is the most common pathogen associated with both symptomatic and asymptomatic bacteriuria. If asymptomatic bacteriuria is untreated, up to 30% of mothers develop acute pyelonephritis, with an increased risk of multiple maternal and neonatal complications, such as preeclampsia, preterm birth, intrauterine growth restriction and low birth weight. Urinary tract infection is a common, but preventable cause of pregnancy complications, thus urinary tests, such as urine culture or new technologies such as high-throughput DNA sequence-based analyses, should be used in order to improve antenatal screening of pregnant women.

A 7-d exercise program increases high-molecular weight adiponectin in obese adults

DEFF Research Database (Denmark)

Kelly, Karen R; Blaszczak, Alecia; Haus, Jacob M

2012-01-01

High-molecular weight (HMW) adiponectin is the biologically active form of adiponectin and is related to enhanced insulin sensitivity and metabolic function. Previously, we found that 7 d of exercise improves insulin sensitivity in obese subjects; however, whether short-term exercise training...

Chemical modification of high molecular weight polyethylene through gamma radiation for biomaterials applications

International Nuclear Information System (INIS)

Raposo, Matheus P.; Rocha, Marisa C.G.

2015-01-01

Ultra high molecular weight polyethylene has been used in the medical field due to its high mechanical properties compared to the other polymers. Its main application is in the development of orthopedic implants, which requires high resistance to abrasion. One of the most used methods is the introduction of crosslinks in the polymer through gamma irradiation. In order to prevent oxidation reactions, studies have been developed using tacoferol (vitamin E) as an antioxidant for the material. The ascorbic acid (vitamin C), however, has been appointed as a viable alternative for vitamin E. In this work, a high molecular weight polyethylene grade (HMWPE) and polyethylene samples formulated with vitamin C were submitted to gamma radiation. Thermodynamic-mechanical methods and gel content determinations were used to characterize the samples obtained. The sample containing 1% of vitamin C and irradiated with 50 KGy of gamma radiation presented the highest content of crosslinks. (author)

Urinary bisphenol A and obesity in adults: results from the Canadian Health Measures Survey

Directory of Open Access Journals (Sweden)

Minh T. Do

2017-12-01

Full Text Available Introduction: Exposure to bisphenol A (BPA has been shown to affect lipid metabolism and promote weight gain in animal studies. Recent epidemiological studies also support a link between BPA and obesity in human populations, although many were limited to a single adiposity measure or have not considered potential confounding by dietary factors. The purpose of this study is to examine associations between urinary BPA and adiposity measures in a nationally representative sample of Canadian adults. Methods: We performed analyses using biomonitoring and directly measured anthropometric data from 4733 adults aged 18 to 79 years in the Canadian Health Measures Survey (2007–2011. We used multinomial and binary logistic regression models to estimate associations of urinary BPA with body mass index (BMI categories (overweight vs. under/normal weight; obesity vs. under/normal weight and elevated waist circumference (males: ≥ 102 cm; females: ≥ 88 cm, respectively, while controlling for potential confounders. Linear regression analyses were also performed to assess associations between urinary BPA and continuous BMI and waist circumference measures. Results: Urinary BPA was positively associated with BMI-defined obesity, with an odds ratio of 1.54 (95% confidence interval [CI]: 1.002–2.37 in the highest (vs. lowest BPA quartile (test for trend, p = .041. Urinary BPA was not associated with elevated waist circumference defined using standard cut-offs. Additionally, each natural-log unit increase in urinary BPA concentration was associated with a 0.33 kg/m2 (95% CI: 0.10–0.57 increase in BMI and a 1.00 cm (95% CI: 0.34–1.65 increase in waist circumference. Conclusion: Our study contributes to the growing body of evidence that BPA is positively associated with obesity. Prospective studies with repeated measures are needed to address temporality and improve exposure classification.

Effect of alkali lignins with different molecular weights from alkali pretreated rice straw hydrolyzate on enzymatic hydrolysis.

Science.gov (United States)

Li, Yun; Qi, Benkun; Luo, Jianquan; Wan, Yinhua

2016-01-01

This study investigated the effect of alkali lignins with different molecular weights on enzymatic hydrolysis of lignocellulose. Different alkali lignins fractions, which were obtained from cascade ultrafiltration, were added into the dilute acid pretreated (DAP) and alkali pretreated (AP) rice straws respectively during enzymatic hydrolysis. The results showed that the addition of alkali lignins enhanced the hydrolysis and the enhancement for hydrolysis increased with increasing molecular weights of alkali lignins, with maximum enhancement being 28.69% for DAP and 20.05% for AP, respectively. The enhancement was partly attributed to the improved cellulase activity, and filter paper activity increased by 18.03% when adding lignin with highest molecular weight. It was found that the enhancement of enzymatic hydrolysis was correlated with the adsorption affinity of cellulase on alkali lignins, and the difference in surface charge and hydrophobicity of alkali lignins were responsible for the difference in affinity between cellulase and lignins. Copyright © 2015 Elsevier Ltd. All rights reserved.

High pressure size exclusion chromatography (HPSEC) determination of dissolved organic matter molecular weight revisited: Accounting for changes in stationary phases, analytical standards, and isolation methods

Science.gov (United States)

McAdams, Brandon C.; Aiken, George R.; McKnight, Diane M.; Arnold, William A.; Chin, Yu-Ping

2018-01-01

We reassessed the molecular weight of dissolved organic matter (DOM) determined by high pressure size exclusion chromatography (HPSEC) using measurements made with different columns and various generations of polystyrenesulfonate (PSS) molecular weight standards. Molecular weight measurements made with a newer generation HPSEC column and PSS standards from more recent lots are roughly 200 to 400 Da lower than initial measurements made in the early 1990s. These updated numbers match DOM molecular weights measured by colligative methods and fall within a range of values calculated from hydroxyl radical kinetics. These changes suggest improved accuracy of HPSEC molecular weight measurements that we attribute to improved accuracy of PSS standards and changes in the column packing. We also isolated DOM from wetlands in the Prairie Pothole Region (PPR) using XAD-8, a cation exchange resin, and PPL, a styrene-divinylbenzene media, and observed little difference in molecular weight and specific UV absorbance at 280 nm (SUVA280) between the two solid phase extraction resins, suggesting they capture similar DOM moieties. PPR DOM also showed lower SUVA280 at similar weights compared to DOM isolates from a global range of environments, which we attribute to oxidized sulfur in PPR DOM that would increase molecular weight without affecting SUVA280.

High Pressure Size Exclusion Chromatography (HPSEC) Determination of Dissolved Organic Matter Molecular Weight Revisited: Accounting for Changes in Stationary Phases, Analytical Standards, and Isolation Methods.

Science.gov (United States)

McAdams, Brandon C; Aiken, George R; McKnight, Diane M; Arnold, William A; Chin, Yu-Ping

2018-01-16

We reassessed the molecular weight of dissolved organic matter (DOM) determined by high pressure size exclusion chromatography (HPSEC) using measurements made with different columns and various generations of polystyrenesulfonate (PSS) molecular weight standards. Molecular weight measurements made with a newer generation HPSEC column and PSS standards from more recent lots are roughly 200 to 400 Da lower than initial measurements made in the early 1990s. These updated numbers match DOM molecular weights measured by colligative methods and fall within a range of values calculated from hydroxyl radical kinetics. These changes suggest improved accuracy of HPSEC molecular weight measurements that we attribute to improved accuracy of PSS standards and changes in the column packing. We also isolated DOM from wetlands in the Prairie Pothole Region (PPR) using XAD-8, a cation exchange resin, and PPL, a styrene-divinylbenzene media, and observed little difference in molecular weight and specific UV absorbance at 280 nm (SUVA 280 ) between the two solid phase extraction resins, suggesting they capture similar DOM moieties. PPR DOM also showed lower SUVA 280 at similar weights compared to DOM isolates from a global range of environments, which we attribute to oxidized sulfur in PPR DOM that would increase molecular weight without affecting SUVA 280 .

A tunable pH-sensing system based on Ag nanoclusters capped by hyperbranched polyethyleneimine with different molecular weights.

Science.gov (United States)

Qu, Fei; Zou, Xuan; Kong, Rongmei; You, Jinmao

2016-01-01

In this assay, a tunable pH sensing system was developed based on Ag nanoclusters (Ag NCs) capped by hyperbranched polyethyleneimine (PEI) with different molecular weights (abbreviated as Ag NC-PEIs). For instance, when the molecular weight of PEI was 600 or 1800, the fluorescence intensities of Ag NCs exhibited a linear fashion over the pH range 4.10-7.96; when the molecular weight of PEI was 25,000, the pH linear range was from 4.78 to 7.96; when the molecular weight of PEI was 70,000, the pH linear range was 6.09-8.95. According to the molecular weight of PEI 600/1800, 25,000, and 70,000, the color change point was pH 4.10-4.78, 5.33-6.09, and 6.09-6.80, respectively. Therefore, Ag NC-PEI 600 and 1800 were proper to acid conditions; Ag NC-PEI 25,000 was sensitive to weak acid media; while Ag NC-PEI 70,000 was adapted to neutral solution. The tunable and selective color change points brought an excellent feature of Ag NC-PEIs as visual pH indicators, which was flexible and applicable to a variety of environments. Besides, the ratios of absorbance at 415 nm and 268 nm of Ag NCs also showed linear relationships with pH variations. Therefore, there were three ways of this system for sensing pH values, including fluorescence assay, ultraviolet-visible measurement, and visual detection, suggesting that this tunable pH-sensing platform was more feasible, reliable, and accurate. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of structure and molecular weight on properties of pressure sensitive adhesives (PSA) formulated from palm oil based urethane acrylate (POBUA)

International Nuclear Information System (INIS)

Mohd Hilmi Mahmood; Shahrol Najmin Baharom; Rida Tajau; Mek Zah Salleh; Khairul Zaman Mohd Dahlan; Rosley Che Ismail

2004-01-01

Various palm oil (RBD Palm Olein) based urethane acrylate prepolymers (UPs) having different structures and molecular weight were synthesized from palm oil based polyols, diisocyanate compounds and hydroxyl terminated acrylate monomers by following established synthesis procedures described elsewhere. The products (UPs) were compared with each other in term of their molecular weight (MW), viscosities and UV curing performances of pressure sensitive adhesives (PSA) UP based formulations. The molecular structure of diisocyanate compounds and hydroxyl acrylate monomers tend to determine the molecular weight and hence viscosities of the final products of urethane acrylate prepolymers (UP), whereas, the MW of the UP has no direct effects on the coatings and adhesive properties of UV curable UP based PSA. (Author)

Effect of Molecular Weight on the Thermal and Spectroscopic Properties of Poly(vinyl alcohol) Films

International Nuclear Information System (INIS)

Khafagy, R.M.; Abd El-Kader, K.M.; Badr, Y.A.

2009-01-01

Thin films of Poly(vinyl alcohol) (PVA) with molecular weights 5000, 17000,72000 and 125000 g/mol were prepared by casting technique.Samples were thermally and spectroscopically investigated using TGA, DSC, FTIR and FT-Raman spectroscopy, in order to show how the thermal stability and structure of PVA might be correlated with its molecular weight. Thermal analysis showed that samples degrade in two steps mechanism. The mechanism observed for degradation in an inert atmosphere was in accordance with the accepted mechanism of elimination followed by pyrolisation. PVA 5000MW and PVA 17000Mw showed almost similar thermal behavior due to their expected similar structure. PVA 72000Mw showed lower thermal stability since it is characterized with the presence of the unstable C-O-C ether linkages, which lead to the fast melting of this sample. PVA 125000Mw showed the highest thermal stability because crosslinking of the main chains takes place due to introducing additional PVA units, which substitute each over oxygen atom. ΔH values obtained from DSC showed good accordance with TGA and Drtg analysis. Moreover, FTIR and FT-Raman results agreed well with thermal analysis, and confirmed our supposed structural changes which might take place as the molecular weight of the sample changes: since the water uptake, presence of ether linkages, and double bonds formulation due to crosslinking, were confirmed with FTIR and FT-Raman spectral analysis. The crystallinity percentage of the samples was calculated from Raman spectra and results confirmed our spectroscopic explanations. The thermal and spectroscopic behavior of the samples was explained as a result of the competitive action of at least three factors due to increasing the molecular weight: (i) diminution of the existing physical network due to changes in hydrogen bonding; (ii) formation of a chemical network; and (iii) introduction of flexible moieties due to the specific chemical structure after crosslinking

Conductivity, dielectric behavior and FTIR studies of high molecular weight poly(vinylchloride)-lithium triflate polymer electrolytes

International Nuclear Information System (INIS)

Ramesh, S.; Chai, M.F.

2007-01-01

Thin films of high molecular weight polyvinyl chloride (PVC) with lithium triflate (LiCF 3 SO 3 ) salt were prepared by solution casting method. The ionic conductivity and dielectric measurements were carried out on these films over a wide frequency regime at various temperatures. The conductivity-temperature plots were found to obey classical Arrhenius relationship. The dielectric behavior was analysed using dielectric permittivity and dielectric modulus of the samples. FTIR studies show some simple overlapping and shift in peaks between high molecular weight polyvinyl chloride (PVC) with lithium triflate (LiCF 3 SO 3 ) salt in the polymer electrolyte complexes

Effect of molecular weight reduction by gamma irradiation on chitosan film properties

Energy Technology Data Exchange (ETDEWEB)

García, Mario A., E-mail: marioifal@gmail.com [Pharmacy and Food Institute, University of Havana, St. 222 No. 2317, ZC 13600 Havana (Cuba); Pérez, Liliam [Pharmacy and Food Institute, University of Havana, St. 222 No. 2317, ZC 13600 Havana (Cuba); Paz, Nilia de la [Drugs Research and Development Center, Ave. 26 No. 1605, Havana (Cuba); González, Juan [Food Industry Research Institute, Carretera al Guatao km 3 1/2, Havana, CP 19200 (Cuba); Rapado, Manuel [Radiobiology Department, Center for Technological Applications and Nuclear Development, St. 30 No. 502, Playa, Havana (Cuba); Casariego, Alicia [Pharmacy and Food Institute, University of Havana, St. 222 No. 2317, ZC 13600 Havana (Cuba)

2015-10-01

The present work aimed the influence of molecular weight (MW) reduction by irradiation with {sup 60}Co and polymer concentration on some physical properties of chitosan films. Irradiation of chitosan with a MW of 275.221 kDa and 74.74% of deacetylation degree was performed using a {sup 60}Co source to provide doses of 5, 10, 20 and 50 kGy to obtain chitosans with molecular weights of 247.847, 221.563, 126.469 and 77.063 kDa, respectively. Films were prepared via the solution casting method. Film-forming solutions (FFS) of chitosan irradiated or not, were prepared at 1.5 and 2% (w/v) in a solution of lactic acid at 1% (v/v) and 0.1% (v/v) of Tween 80. The FFS were poured into glass plates of 400 cm{sup 2} and dried at 60 °C during 10 h without airflow. The decrease of MW and increase of chitosan concentration increased the tensil strength and water vapor permeability while decreased the elongation at break of the films. The chitosan MW did not significantly influence (p > 0.05) the water solubility of films within a same polymer concentration. There was a decrease in the films' brightness with the increase of concentration and a decrease of the MW of irradiated chitosan, while the b* values of films increased and there was an increasing tendency of their apparent opacity. - Highlights: • MW reduction by {sup 60}Co irradiation increased the tensil strength of chitosan films. • MW reduction increased the water vapor permeability of chitosan films. • MW did not affect the films' water solubility within a same chitosan concentration. • Films' brightness decreased with the chitosan molecular weight reduction.

Effect of molecular weight reduction by gamma irradiation on chitosan film properties

International Nuclear Information System (INIS)

García, Mario A.; Pérez, Liliam; Paz, Nilia de la; González, Juan; Rapado, Manuel; Casariego, Alicia

2015-01-01

The present work aimed the influence of molecular weight (MW) reduction by irradiation with 60 Co and polymer concentration on some physical properties of chitosan films. Irradiation of chitosan with a MW of 275.221 kDa and 74.74% of deacetylation degree was performed using a 60 Co source to provide doses of 5, 10, 20 and 50 kGy to obtain chitosans with molecular weights of 247.847, 221.563, 126.469 and 77.063 kDa, respectively. Films were prepared via the solution casting method. Film-forming solutions (FFS) of chitosan irradiated or not, were prepared at 1.5 and 2% (w/v) in a solution of lactic acid at 1% (v/v) and 0.1% (v/v) of Tween 80. The FFS were poured into glass plates of 400 cm 2 and dried at 60 °C during 10 h without airflow. The decrease of MW and increase of chitosan concentration increased the tensil strength and water vapor permeability while decreased the elongation at break of the films. The chitosan MW did not significantly influence (p > 0.05) the water solubility of films within a same polymer concentration. There was a decrease in the films' brightness with the increase of concentration and a decrease of the MW of irradiated chitosan, while the b* values of films increased and there was an increasing tendency of their apparent opacity. - Highlights: • MW reduction by 60 Co irradiation increased the tensil strength of chitosan films. • MW reduction increased the water vapor permeability of chitosan films. • MW did not affect the films' water solubility within a same chitosan concentration. • Films' brightness decreased with the chitosan molecular weight reduction

Dextran: Influence of Molecular Weight in Antioxidant Properties and Immunomodulatory Potential.

Science.gov (United States)

Soeiro, Vinicius C; Melo, Karoline R T; Alves, Monique G C F; Medeiros, Mayara J C; Grilo, Maria L P M; Almeida-Lima, Jailma; Pontes, Daniel L; Costa, Leandro S; Rocha, Hugo A O

2016-08-19

Dextrans (α-d-glucans) extracted from Leuconostoc mesenteroides, with molecular weights (MW) of 10 (D10), 40 (D40) and 147 (D147) kDa, were evaluated as antioxidant, anticoagulant and immunomodulatory drugs for the first time. None presented anticoagulant activity. As for the antioxidant and immunomodulatory tests, a specific test showed an increase in the dextran activity that was proportional to the increase in molecular weight. In a different assay, however, activity decreased or showed no correlation to the MW. As an example, the reducing power assay showed that D147 was twice as potent as other dextrans. On the other hand, all three samples showed similar activity (50%) when it came to scavenging the OH radical, whereas only the D10 sample showed sharp activity (50%) when it came to scavenging the superoxide ion. D40 was the single dextran that presented with immunomodulatory features since it stimulated the proliferation (~50%) of murine macrophages (RAW 264.7) and decreased the release of nitric oxide (~40%) by the cells, both in the absence and presence of lipopolysaccharides (LPS). In addition, D40 showed a greater scavenging activity (50%) for the hydrogen peroxide, which caused it to also be the more potent dextran when it came to inhibiting lipid peroxidation (70%). These points toward dextrans with a 40 kDa weight as being ideal for antioxidant and immunomodulatory use. However, future studies with the D40 and other similarly 40 kDa dextrans are underway to confirm this hypothesis.

Parturition events and risk of urinary incontinence in later life.

Science.gov (United States)

Thom, David H; Brown, Jeanette S; Schembri, Michael; Ragins, Arona I; Creasman, Jennifer M; Van Den Eeden, Stephen K

2011-11-01

To examine the association between specific events during vaginal deliveries and urinary incontinence later in life. A retrospective cohort study of 1,521 middle-aged and older women with at least one vaginal delivery who were long-term members of an integrated health delivery system. Age, race/ethnicity, current incontinence status, medical, surgical history, pregnancy and parturition history, menopausal status, hormone replacement, health habits, and general health were obtained by questionnaire. Labor and delivery records, archived since 1948, were abstracted by professional medical record abstractors to obtain parturition events including induction, length of labor stages, type of anesthesia, episiotomy, instrumental delivery, and birth weight. The primary dependent variable was current weekly urinary incontinence (once per week or more often) versus urinary incontinence less than monthly (including no incontinence) in past 12 months. Associations of parturition events and later incontinence were assessed in multivariate analysis with logistic regression. The mean age of participants was 56 years. After adjustment for multiple risk factors, weekly urinary incontinence significantly associated with age at first birth (P = 0.036), greatest birth weight (P = 0.005), and ever having been induced for labor (OR = 1.51; 95%CI = 1.06-2.16, P = 0.02). Risk of incontinence increased from OR = 1.35 (95%CI = 0.92-1.97, P = 0.12) for women with one induction to OR = 2.67 (95%CI = 1.25-5.71, P = 0.01) for women with two or more inductions (P = 0.01 for trend). No other parturition factors were associated with incontinence. Younger age at first birth, greatest birth weight, and induction of labor were associated with an increased risk of incontinence in later life. Copyright © 2011 Wiley Periodicals, Inc.

Hofmeister effect on thermo-responsive poly(propylene oxide): Role of polymer molecular weight and concentration.

Science.gov (United States)

Moghaddam, Saeed Zajforoushan; Thormann, Esben

2016-03-01

Although a vast amount of research has been dedicated to investigate the Hofmeister effect on the stability of polymer solutions, a clear understanding of the role of polymer properties in this phenomenon is still missing. Here, the Hofmeister effect of NaCl (destabilizing) and NaSCN (stabilizing) salts on aqueous solutions of poly(propylene oxide) (PPO) is studied. Four different molecular weights of PPO were investigated, to determine how the variation in the polymer coil size affects the Hofmeister effect. The investigation was further conducted for different PPO concentrations, in order to understand the effect of inter-chain interactions on the response to addition of salt. The temperature-driven phase separation of the solutions was monitored by differential scanning calorimetry, which provides the precise value of the phase separation temperature, as well as the enthalpy change accompanied with the transition. It was observed that increasing the molecular weight weakens the effect of the both salts, which is interpreted in terms of a scaling law between the molecular weight and the accessible surface area of the polymers. Increasing the PPO concentration further diminished the NaCl effect, but amplified the NaSCN effect. This difference is attributed to an electrostatic stabilization mechanism in the case of NaSCN. Copyright © 2015 Elsevier Inc. All rights reserved.

Prolonged use of indwelling urinary catheter following acute urinary ...

African Journals Online (AJOL)

J.O. Bello

prolonged use of urinary catheters following acute urinary retention secondary to benign prostate enlarge- ment (BPE) and urethral ... indwelling urinary catheter for >3 months following acute urinary retention due to BPE or USD. The study .... the major health-care financing strategy in Nigeria and accounts for more than ...

FY 1991 Report on the results of the research and development of silicon-based high-molecular-weight materials; 1991 nendo keisokei kobunshi zairyo no kenkyu kaihatsu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1992-03-01

The research and development project has been started to establish the basic technologies for molecular designs, synthesis, material production and evaluation of silicon-based high-molecular-weight materials expected to exhibit excellent characteristics, e.g., electro-optical functions, resistance to heat, flame retardance and mechanical properties. The efforts in FY 1991, the first year for the 10-year project, are mainly directed to the surveys on the R and D trends, both domestic and foreign, to clarify the relationship between the structures and functions/properties. The R and D projects followed include the technologies for synthesizing (1) electroconductive silicon-based high-molecular-weight materials, (2) novel silicon-based high-molecular-weight materials capable of drawing circuits, (3) novel, light-emitting silicon-based high-molecular-weight materials and (4) silicon-based opto-electric conversion materials for the electro-optical functional high-molecular-weight materials; and (1) synthesis of high-molecular-weight structural materials of sea island structure, (2) technologies for forming inter-penetrating type structures (IPN), (3) development of composite structural materials of organometallic complex and silicon-based high-molecular-weight material, and (4) development of silicon-based high-molecular-weight materials of ring structure for the high-molecular-weight structural materials. (NEDO)

Primary Prevention of Urinary Incontinence: A Case Study of Prenatal and Intrapartum Interventions.

Science.gov (United States)

Kissler, Katherine; Yount, Susan M; Rendeiro, Melissa; Zeidenstein, Laura

2016-07-01

A wealth of information is available regarding the diagnosis and treatment of urinary incontinence. However, there is a dearth of quality information and clinical practice guidelines regarding the primary prevention of urinary incontinence. Given the high prevalence of this concern and the often cited correlation between pregnancy, childbirth, and urinary incontinence, women's health care providers should be aware of risk factors and primary prevention strategies for stress urinary incontinence (SUI) in order to reduce associated physical and emotional suffering. This case report describes several common risk factors for SUI and missed opportunities for primary prevention of postpartum urinary incontinence. The most effective methods for preventing urinary incontinence include correct teaching of pelvic floor muscle training (PFMT; specifically Kegel exercises), moderate combined physical exercise regimens, counseling and support for weight loss, counseling against smoking, appropriate treatment for asthma and constipation, and appropriate labor management to prevent pelvic organ prolapse, urethral injury, and pelvic floor muscle damage. © 2016 by the American College of Nurse-Midwives.

[Effects of excess pyridoxine-HCl on growth and urinary excretion of water-soluble vitamins in weaning rats].

Science.gov (United States)

Fukuwatari, Tsutomu; Itoh, Keiko; Shibata, Katsumi

2009-04-01

To determine the tolerable upper intake level of pyridoxine-HCl in humans, we investigated the effects of excess pyridoxine-HCl administration on body weight gain, food intake, tissue weight, and urinary excretion of water-soluble vitamins in weaning rats. The weaning rats were freely fed ordinary diet containing 0.0007% pyridoxine-HCl (control diet) or the same diet with 0.1%, 0.5%, 0.8% or 1.0% pyridoxine-HCl for 30 days. The body weight gain in the 0.8% and 1.0% groups, and the total food intake in the 1.0% group were significantly lower than those in the control group. The urinary excretion of pantothenic acid in the pyridoxine-HCl added groups were higher than that in the control group, while excessive pyridoxine-HCl intake did not affect the urinary excretion of other water-soluble vitamins. These results showed that the no-observed-adverse-effect-level (NOAEL) for pyridoxine-HCl was 0.1% in diet, corresponding to 90 mg/kg body weight/day, and lowest-observed-adverse-effect-level (LOAEL) was 0.5% in diet, corresponding to 450 mg/kg body weight/day.

Influence of gender on the correlation between plasma growth hormone profiles and urinary growth hormone excretion

DEFF Research Database (Denmark)

Main, K M; Jansson, C; Skakkebak, N

1997-01-01

A lot of interest has been directed towards the measurement of urinary growth hormone (GH) excretion instead of plasma GH profiles or provocation tests. We investigated the factors influencing the relationship between 24- and 3-hour plasma GH profiles and urinary GH excretion in a cohort of 113...... than spontaneous GH peaks. The difference in cross-reactivities of molecular GH forms in polyclonal assays may have an impact on the correlation between plasma and urinary GH. Thus, the diagnostic value of urinary GH measurement as compared to serum GH profiles needs to be further evaluated....

Separation and analysis of low molecular weight plasticizers in poly(vinyl chloride) tubes

DEFF Research Database (Denmark)

Wang, Qian; Storm, Birgit Kjærside

2005-01-01

) and thermogravimetric analysis (TGA), as well as by studying the extracted low molecular weight plasticizers by gas chromatography/mass spectroscopy (GC/MS) and GC. It was found that the simple room temperature extraction in chloroform showed the best separation of plasticizers from the PVC matrix. Close results...

Evaluation of scission and crosslinking yields in γ-irradiated poly(acrylic acid) and poly(methacrylic acid) from weight- and Ζ-average molecular weights determined by sedimentation equilibrium

International Nuclear Information System (INIS)

Hill, D.J.T.; O'Donnell, J.H.; Winzor, C.L.; Winzor, D.J.

1990-01-01

Weight- and Ζ-average molecular weights, M-bar W (D) and M-bar Ζ (D), of poly(methacrylic acid) (PMMA) and poly(acrylic acid) (PAA) have been determined by sedimentation equilibrium in the ultracentrifuge after various doses D of γ-radiation in vacuum. Relationships between [M i (0)/M i (D)-1]/D and D (i=w or Ζ), derived recently by O'Donnell and coworkers, have been used to determine radiation chemical yields for scission and crosslinking of G(S)=6.0, G(X)=0 for PMAA and G(S)=0, G(X)=0.44 for PAA. Allowance was necessary for the effects of COOH decomposition on the average values of the molecular weight and partial specific volume for irradiated PAA. (author)

Phase behaviour of oat β-glucan/sodium caseinate mixtures varying in molecular weight.

Science.gov (United States)

Agbenorhevi, Jacob K; Kontogiorgos, Vassilis; Kasapis, Stefan

2013-05-01

The isothermal phase behaviour at 5 °C of mixtures of sodium caseinate and oat β-glucan isolates varying in molecular weight (MW) was investigated by means of phase diagram construction, rheometry, fluorescence microscopy and electrophoresis. Phase diagrams indicated that the compatibility of the β-glucan/sodium caseinate system increases as β-glucan MW decreases. Images of mixtures taken at various biopolymer concentrations revealed phase separated domains. Results also revealed that at the state of thermodynamic equilibrium, lower MW samples yielded considerable viscosity in the mixture. At equivalent hydrodynamic volume of β-glucan in the mixtures, samples varying in molecular weight exhibited similar flow behaviour. A deviation dependent on the protein concentration was observed for the high MW sample in the concentrated regime due to the size of β-glucan aggregates formed. Results demonstrate that by controlling the structural features of β-glucan in mixtures with sodium caseinate, informed manipulation of rheological properties in these systems can be achieved. Copyright © 2012 Elsevier Ltd. All rights reserved.

Preparation of Low Molecular Weight Gelatin Using Microwave Discharge Electrodeless Lamp/TiO2 Photocatalyst Hybrid System.

Science.gov (United States)

Lee, Do-Jin; Kim, Hangun; Park, Young-Kwon; Kim, Byung Hoon; Lee, Heon; Jungf, Sana-Chul

2016-02-01

In this study, an MDEL/TiO2 photocatalyst hybrid system was applied to the production of low molecular weight gelatin. The molecular weight of produed gelatin decreased with increasing microwave intensity and increasing treatment time. The abscission of the chemical bonds between the con- stituents of gelatin by photocatalytic reaction did not alter the characteristics of gelatin. Formation of any by-products due to side reaction was not observed. It is suggested that gelatin was depolymerized by hydroxyl radicals produced during the MDEL/TiO2 photochemical reaction.

Preparation of Low Molecular Weight Heparin by Microwave Discharge Electrodeless Lamp/TiO2 Photo-Catalytic Reaction.

Science.gov (United States)

Lee, Do-Jin; Kim, Byung Hoon; Kim, Sun-Jae; Kim, Jung-Sik; Lee, Heon; Jung, Sang-Chul

2015-01-01

An MDEL/TiO2 photo-catalyst hybrid system was applied, for the first time, for the production of low molecular weight heparin. The molecular weight of produed heparin decreased with increasing microwave intensity and treatment time. The abscission of the chemical bonds between the constituents of heparin by photo-catalytic reaction did not alter the characteristics of heparin. Formation of by-products due to side reaction was not observed. It is suggested that heparin was depolymerized by active oxygen radicals produced during the MDEL/TiO2 photo-chemical reaction.

Ring-opening polymerization of 19-electron [2]cobaltocenophanes: a route to high-molecular-weight, water-soluble polycobaltocenium polyelectrolytes.

Science.gov (United States)

Mayer, Ulrich F J; Gilroy, Joe B; O'Hare, Dermot; Manners, Ian

2009-08-05

Water-soluble, high-molecular-weight polycobaltocenium polyelectrolytes have been prepared by ring-opening polymerization (ROP) techniques. Anionic polymerization of a strained 19-electron dicarba[2]cobaltocenophane followed by oxidation in the presence of ammonium chloride resulted in the formation of oligomers with up to nine repeat units. Thermal ROP of dicarba[2]cobaltocenophane followed by oxidation in the presence of ammonium nitrate resulted in the formation of high-molecular-weight polycobaltocenium nitrate, a redox-active cobalt-containing polyelectrolyte.

Risperidone-associated urinary incontinence in patients with autistic disorder with mental retardation.

Science.gov (United States)

Kumazaki, Hirokazu; Watanabe, Koichiro; Imasaka, Yasushi; Iwata, Kazuhiko; Tomoda, Akemi; Mimura, Masaru

2014-10-01

We report several cases in which patients with autistic disorder with mental retardation who received risperidone experienced urinary incontinence. We retrospectively investigated the medical records of patients housed in facilities for patients with autistic disorder with mental retardation. Those who had undergone a medical examination at a hospital in Tokyo from April 1999 to March 2009 were included in the study.Retrospective data were gathered including age, sex, IQ, birth weight, dosage of risperidone, urinary density, as well as existence of urinary and fecal incontinence. We divided the participants into those who did and did not experience urinary incontinence after taking risperidone and compared the 2 groups. Risperidone had been prescribed to 35 patients. In spite of the fact that no patient had a history of urinary incontinence, 14 patients experienced urinary incontinence after receiving risperidone. Moreover, 4 of these 14 patients also had fecal incontinence. Among the variables we examined, the only significant difference between groups was in sex, with significantly more women experiencing incontinence compared with men. When the dose of risperidone was reduced or the patients switched to other drugs, urinary incontinence of the patients improved.Hence, risperidone may have a casual relationship with urinary incontinence. Further research is needed to understand the pathophysiology of possible effect.

Primary malignant melanoma of the urinary bladder: clinical, morphological, and molecular analysis of five cases.

Science.gov (United States)

Karabulut, Yasemin Y; Erdogan, Seyda; Sayar, Hamide; Ergen, Ali; Ertoy Baydar, Dilek

2016-12-01

The aim of our study was to evaluate the clinical and morphological features of primary malignant melanomas of the urinary bladder. We obtained information on five such cases from three different institutions. These were three men and two women between 52 and 76 years of age. Three tumors presented with hematuria, one with dysuria, and one was discovered incidentally on imaging studies. All were invasive to muscularis propria on transuretral resections performed for diagnosis. Neoplastic cells showed variable patterns (large cell epithelioid, small cell diffuse, storiform, or mixed) in different tumors. Pigmentation was prominent in all except one case. Each case was labeled diffusely for S-100, HMB-45, and Melan-A. Pan-cytokeratin showed a perinuclear dot-like reaction in two tumors. Three cases showed the BRAF mutation in molecular studies. Two patients were already metastatic at the time of diagnosis. Two patients died, one is alive with disease after 15 months, and two patients are disease free at 1 and 5 years of surveillance.

Conductivity, dielectric behavior and FTIR studies of high molecular weight poly(vinylchloride)-lithium triflate polymer electrolytes

Energy Technology Data Exchange (ETDEWEB)

Ramesh, S. [Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Setapak, 53300 Kuala Lumpur (Malaysia)]. E-mail: ramesh@mail.utar.edu.my; Chai, M.F. [Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Setapak, 53300 Kuala Lumpur (Malaysia)

2007-05-15

Thin films of high molecular weight polyvinyl chloride (PVC) with lithium triflate (LiCF{sub 3}SO{sub 3}) salt were prepared by solution casting method. The ionic conductivity and dielectric measurements were carried out on these films over a wide frequency regime at various temperatures. The conductivity-temperature plots were found to obey classical Arrhenius relationship. The dielectric behavior was analysed using dielectric permittivity and dielectric modulus of the samples. FTIR studies show some simple overlapping and shift in peaks between high molecular weight polyvinyl chloride (PVC) with lithium triflate (LiCF{sub 3}SO{sub 3}) salt in the polymer electrolyte complexes.

Urinary tract infections during pregnancy.

Science.gov (United States)

Le, Jennifer; Briggs, Gerald G; McKeown, Anna; Bustillo, Gerardo

2004-10-01

To provide a comprehensive review of urinary tract infections (UTIs) during pregnancy. All aspects of UTIs, including epidemiology, pathogenesis, resistance, clinical features, diagnosis, treatment, and prevention, were reviewed. MEDLINE (1966-August 2003) and Cochrane Library searches were performed using the key search terms urinary tract infection, pyelonephritis, cystitis, asymptomatic bacteriuria, and resistance. All article abstracts were evaluated for relevance. Only articles pertaining to pregnancy were included. The majority of published literature were review articles; the number of original clinical studies was limited. UTIs are the most common bacterial infections during pregnancy. They are characterized by the presence of significant bacteria anywhere along the urinary tract. Pyelonephritis is the most common severe bacterial infection that can lead to perinatal and maternal complications including premature delivery, infants with low birth weight, fetal mortality, preeclampsia, pregnancy-induced hypertension, anemia, thrombocytopenia, and transient renal insufficiency. Enterobacteriaceae account for 90% of UTIs. The common antibiotics used are nitrofurantoin, cefazolin, cephalexin, ceftriaxone, and gentamicin. Therapeutic management of UTIs in pregnancy requires proper diagnostic workup and thorough understanding of antimicrobial agents to optimize maternal outcome, ensure safety to the fetus, and prevent complications that lead to significant morbidity and mortality in both the fetus and the mother.

Horseradish extract promotes urinary bladder carcinogenesis when administered to F344 rats in drinking water.

Science.gov (United States)

Cho, Young-Man; Hasumura, Mai; Imai, Toshio; Takami, Shigeaki; Nishikawa, Akiyoshi; Ogawa, Kumiko

2017-07-01

Horseradish extract (HRE), consisting mainly of a mixture of allyl isothiocyanate and other isothiocyanates, has been used as a food additive. To evaluate the potential hazards of HRE, a 104-week chronic study, a 2-week analysis of cell proliferation in the urinary bladder and a medium-term promotion bioassay of HRE were conducted with administration at concentrations of up to 0.04% HRE in the drinking water to male F344 rats. In the 104-week chronic study with 32 male rats per group, no treatment-related increases in the incidences of neoplastic lesions in any organ, including urinary bladder, were observed, except for simple hyperplasia in the urinary bladder in rats treated with HRE at concentrations of more than 0.01% (5.0 mg kg -1 body weight day -1 ). In the promotion study, HRE treatment after N-butyl-N-(4-hydroxybutyl)nitrosamine initiation caused a clear increase in papillary or nodular hyperplasia, papilloma, and urothelial carcinoma of the urinary bladder in the groups given HRE for 13 weeks at doses higher than 0.005%, 0.01%, and 0.04% (2.7, 5.4 and 20.5 mg kg -1 body weight day -1 ), respectively. In the 2-week cell proliferation analysis, treatment with HRE at concentrations greater than 0.005% (3.9 mg kg -1 body weight day -1 ) caused transient increases in 5-bromo-2'-deoxyuridine labeling indices in the urothelium. Although clear tumor induction was not observed, administration of relatively low-dose HRE increased cell proliferation in the urothelium and exerted obvious promoting effects on rat urinary bladder carcinogenesis. Further studies are needed to elucidate the mode of action of HRE in the rat urinary bladder to facilitate data extrapolation from the present study and provide insights into risk assessment. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Role of body mass index in school-aged children with lower urinary tract dysfunction: Does weight classification predict treatment outcome?

Science.gov (United States)

Arlen, Angela M; Cooper, Christopher S; Leong, Traci

2017-10-01

Lower urinary tract (LUT) dysfunction comprises a large percentage of pediatric urology referrals. Childhood obesity is a major health concern, and has been associated with voiding symptoms. We assessed the impact of body mass index (BMI) on treatment outcomes of children presenting with LUT or bladder-bowel dysfunction (BBD). Children aged 5-17 years diagnosed with non-neurogenic LUT dysfunction and no prior urologic diagnoses were identified. Patient demographics including BMI, lower urinary tract symptoms, constipation, medical and psychologic comorbidities, imaging, and treatment outcomes were evaluated. BMI was normalized by age and gender according to percentiles: underweight  95th percentile. Uni- and multivariate analyses were performed to identify predictors of treatment response. During an 18-month period, 100 children (54 girls, 46 boys) met the inclusion criteria. The mean age at diagnosis was 7.7 ± 2.4 years, and mean length of follow-up 15.3 ± 13.1 months. Sixty-nine patients were a normal weight, 22 were overweight, and nine were obese. Fifteen percent of the children had complete treatment response, 63% partial response, and 22% non-response. On univariate analysis, children with elevated BMI (p = 0.04) or history of urinary tract infection (p = 0.01) were statistically more likely to not respond to treatment. Controlling for all other variables, children with BMI > 85th percentile had 3.1 times (95% CI 1.11-8.64; p = 0.03) increased odds of treatment failure (Table). BBD management includes implementation of a bowel program and timed voiding regimen, with additional treatment modalities tailored on the basis of the prevailing symptoms. We observed that school-aged children with a BMI ≥ 85th percentile were over three times more likely to experience treatment failure when controlling for all other patient characteristics including constipation and a history of urinary tract infection. Limitations of the study include the

Changes in urinary response in the soccer practice

Directory of Open Access Journals (Sweden)

M.A. López-Mata

2012-02-01

Full Text Available The objective of this study was to evaluate the chemical parameters and urinary sediment changes before and after a soccer game. Seventeen players were selected from a selective universitary men's soccer team (age 21,8 ± 1,38 years, weight 73,2 ± 11,8 kg, height 1,71 ± 0,07 m and BMI 24,7 ± 2.3 kg/m2. Chemical parameters of the urine (specific gravity, pH, leukocytes, nitrite, proteins, glucose, bodies ketones, urobilinogene, bilirubin and erythrocytes and sediment (leukocytes, erythrocytes, crystals, epithelial cells, bacteria, casts, and mucine filaments were determined. We found a significant increase of specific gravity before and after of competition (1,019 ± 0.005 vs 1,025 ± 0.004; p= 0,0001, pH (6,0 ± 0,91 vs 5,35 ± 0,60; p= 0,008 urinary and in presence of bilirubin (0% vs 41,2%; p= 0,01. In urinary sediment was found a significant rise in the presence of casts (0% vs 29,4%; p= 0,04 and mucin filaments (11,7% vs 64,7% p= 0,004. Although some changes were found in urinary parameters, these chances may have been influenced by an increase in renal reabsortion of water.Key words: Soccer, urinary parameters, bilirubin, mucin, casts

Changes in urinary response in the soccer practice

Directory of Open Access Journals (Sweden)

M.A. López-Mata

2012-02-01

Full Text Available The objective of this study was to evaluate the chemical parameters and urinary sediment changes before and after a soccer game. Seventeen players were selected from a selective universitary men's soccer team (age 21,8 ± 1,38 years, weight 73,2 ± 11,8 kg, height 1,71 ± 0,07 m and BMI 24,7 ± 2.3 kg/m2. Chemical parameters of the urine (specific gravity, pH, leukocytes, nitrite, proteins, glucose, bodies ketones, urobilinogene, bilirubin and erythrocytes and sediment (leukocytes, erythrocytes, crystals, epithelial cells, bacteria, casts, and mucine filaments were determined. We found a significant increase of specific gravity before and after of competition (1,019 ± 0.005 vs 1,025 ± 0.004; p= 0,0001, pH (6,0 ± 0,91 vs 5,35 ± 0,60; p= 0,008 urinary and in presence of bilirubin (0% vs 41,2%; p= 0,01. In urinary sediment was found a significant rise in the presence of casts (0% vs 29,4%; p= 0,04 and mucin filaments (11,7% vs 64,7% p= 0,004. Although some changes were found in urinary parameters, these chances may have been influenced by an increase in renal reabsortion of water. Key words: Soccer, urinary parameters, bilirubin, mucin, casts

Role of Molecular Weight on the Mechanical Device Properties of Organic Polymer Solar Cells

KAUST Repository

Bruner, Christopher; Dauskardt, Reinhold

2014-01-01

important implications for long-Term reliability, manufacturing, and future applications of electronic organic thin films. In this work, we show that the molecular weight rr-P3HT in organic solar cells can also significantly change the internal cohesion

Controlling the Molecular Weight of Lignosulfonates by an Alkaline Oxidative Treatment at Moderate Temperatures and Atmospheric Pressure: A Size-Exclusion and Reverse-Phase Chromatography Study

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Chamseddine Guizani

2017-11-01

Full Text Available The molecular weights of lignosulfonates (LSs are modified by a rather simple process involving an alkaline oxidative treatment at moderate temperatures (70–90 °C and atmospheric pressure. Starting from LSs with an average molecular weight of 90,000 Da, and using such a treatment, one can prepare controlled molecular weight LSs in the range of 30,000 to 3500 Da based on the average mass molecular weight. The LS depolymerisation was monitored via reverse-phase and size-exclusion chromatography. It has been shown that the combination of O2, H2O2 and Cu as a catalyst in alkaline conditions at 80 °C induces a high LS depolymerisation. The depolymerisation was systemically accompanied by a vanillin production, the yields of which reached 1.4 wt % (weight percentage on LS raw basis in such conditions. Also, the average molecular weight and vanillin concentration were correlated and depended linearly on the temperature and reaction duration.

Molecular weight control in emulsion polymerization by catalytic chain transfer : a reaction engineering approach

NARCIS (Netherlands)

Smeets, N.M.B.; Meda, U.S.; Heuts, J.P.A.; Keurentjes, J.T.F.; Herk, van A.M.; Meuldijk, J.

2007-01-01

For the application of catalytic chain transfer in (mini)emulsion polymerization, catalyst partitioning and deactivation are key parameters that govern the actual catalyst concentration at the locus of polymerization and consequently the final molecular weight distribution. A global model, based on

Molecular weight dependence of exciton diffusion in poly(3-hexylthiophene)

DEFF Research Database (Denmark)

Masri, Zarifi; Ruseckas, Arvydas; Emelianova, Evguenia V.

2013-01-01

A joint experimental and theoretical study of singlet exciton diffusion in spin-coated poly(3-hexylthiophene) (P3HT) films and its dependence on molecular weight is presented. The results show that exciton diffusion is fast along the co-facial π–π aggregates of polymer chromophores and about 100...... times slower in the lateral direction between aggregates. Exciton hopping between aggregates is found to show a subtle dependence on interchain coupling, aggregate size, and Boltzmann statistics. Additionally, a clear correlation is observed between the effective exciton diffusion coefficient...

[A giant fecalith complicated by acute urinary retention, hydronephrosis and acute obstructive pyelonephritis].

Science.gov (United States)

Davidov, M I

2016-04-01

The article reports a rare case of a 30-year-old man with Hirschsprung's disease, who developed a giant fecalith in the rectum and sigmoid (weight 3.5 kg, the largest diameter 20 cm). The fecalith impaired urine flow by compressing urinary tract, thereby causing acute urinary retention and right-sided hydronephrosis with acute obstructive pyelonephritis. Removing fecalith resulted in the patient recovery and normal functioning of genitourinary system.

Urinary transforming growth factors in neoplasia: separation of 125I-labeled transforming growth factor-alpha from epidermal growth factor in human urine

International Nuclear Information System (INIS)

Stromberg, K.; Hudgins, W.R.

1986-01-01

Purified human epidermal growth factor (hEGF) from urine promotes anchorage-independent cell growth in soft agar medium. This growth is enhanced by transforming growth factor-beta (TGF-beta), and is specifically inhibited by hEGF antiserum. Transforming growth factors of the alpha type (TGF-alpha), potentially present in normal human urine or urine from tumor-bearing patients, also promote anchorage-independent cell growth and compete with EGF for membrane receptor binding. Consequently, TGF-alpha cannot be distinguished from urinary hEGF by these two functional assays. Therefore, a technique for separation of TGF-alpha and related peptides from urinary EGF based on biochemical characteristics would be useful. Radioiodination of characterized growth factors [mouse EGF (mEGF), hEGF, and rat TGF-alpha (rTGF-alpha)], which were then separately added to human urine, was used to evaluate a resolution scheme that separates TGF-alpha from the high level of background hEGF present in human urine. Methyl bonded microparticulate silica efficiently adsorbed the 125 I-labeled mEGF, 125 I-labeled hEGF, and 125 I-labeled rTGF-alpha that were added to 24-h human urine samples. Fractional elution with acetonitrile (MeCN) of the adsorbed silica released approximately 70 to 80% of the 125 I-labeled mEGF and 125 I-labeled hEGF between 25 and 30% MeCN, and over 80% of the 125 I-labeled rTGF-alpha between 15 and 25% MeCN, with retention after dialysis of less than 0.2 and 1.7% of the original urinary protein, respectively. A single-step enrichment of about 400-fold for mEGF and hEGF, and 50-fold for rTGF-alpha were achieved rapidly. 125 I-labeled mEGF and 125 I-labeled hEGF eluted later than would be predicted on the basis of their reported molecular weight of approximately 6000, whereas 125 I-labeled rTGF-alpha eluted from Bio-Gel P-10 at an approximate molecular weight of 8000 to 9000

Purification of a large molecular weight transglutaminase substrate from liver plasma membranes

International Nuclear Information System (INIS)

Slife, C.W.; Morris, G.S.; Tyrrell, D.J.

1986-01-01

Transglutaminases are enzymes which catalyze the covalent crosslinking of proteins by forming epsilon(γ-glutamyl)lysine isopeptide linkages. In earlier studies, the authors reported that a large molecular weight protein aggregate in rat liver plasma membranes served as a substrate for a plasma membrane-associated transglutaminase. The enzyme specifically incorporated a lysine analog, [ 3 H]putrescine, into a protein complex which remained at the top of an acrylamide gel upon electrophoresis in SDS and reducing agents. The complex has now been isolated by extracting the plasma membranes with detergent (octylglucoside) resuspending the detergent insoluble residues in 6 M guanidine HCl and chromatographing the residue on a 4% agarose column in 6 M guanidine HCl. Most of the radioactivity is found in the void volume fractions from the column. SDS polyacrylamide gel electrophoresis shows that these fractions contain mostly proteins that do not enter the acrylamide gel. Since this purification procedure is essentially the same as that used to isolate a rat hepatocyte adhesion factor from rat liver plasma membranes it is possible that the large molecular weight transglutaminase substrate and the adhesion factor are contained in the same protein aggregate

Polysaccharides and their depolymerized fragments from Costaria costata: Molecular weight and sulfation-dependent anticoagulant and FGF/FGFR signal activating activities.

Science.gov (United States)

Hou, Ningning; Zhang, Meng; Xu, Yingjie; Sun, Zhongmin; Wang, Jing; Zhang, Lijuan; Zhang, Quanbin

2017-12-01

Crude polysaccharides from Costaria costata were extracted by hot water and further fractionated by anion exchange chromatography into three polysaccharide fractions. Three low molecular weight fragments were then prepared by degradation of the polysaccharides with hydrogen peroxide and ascorbic acid. The structural features of the polysaccharides and their low molecular weight fragments were elucidated for the first time based on the HGPC, FT-IR, NMR, MS, monosaccharide composition, and other chemical analyses. Their anticoagulant and FGF-1, -2, -7, -8, -9, -10/FGFR1c signaling activation activities in BaF3 cells were also examined. Our studies showed that the polysaccharides were sulfated at different positions of galactose and fucose residues. The APTT-, PT- and TT-based anticoagulant assay results indicated that a high molecular weight and a higher degree of sulfation were essential for their anticoagulant activities. In contrast, not only the polysaccharides but also the depolymerized fragments showed significant FGF/FGFR signal activating activities in a FGF-, molecular weight-, and sulfation-dependent manner. The results presented in current study demonstrated the potential use of the polysaccharides and their fragments as anticoagulants and FGF signal regulators. Copyright © 2017 Elsevier B.V. All rights reserved.

Role of Laccase and Low Molecular Weight Metabolites from Trametes versicolor in Dye Decolorization

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Diego Moldes

2012-01-01

Full Text Available The studies regarding decolorization of dyes by laccase may not only inform about the possible application of this enzyme for environmental purposes, but also may provide important information about its reaction mechanism and the influence of several factors that could be involved. In this paper, decolorization of crystal violet and phenol red was carried out with different fractions of extracellular liquids from Trametes versicolor cultures, in order to describe the role of laccase in this reaction. Moreover, the possible role of the low molecular weight metabolites (LMWMs also produced by the fungus was evaluated. The results confirm the existence of a nonenzymatic decolorization factor, since the nonprotein fraction of the extracellular liquids from cultures of T. versicolor has shown decolorization capability. Several experiments were performed in order to identify the main compounds related to this ability, which are probably low molecular weight peroxide compounds.

New paradigms of urinary tract infections: Implications for patient management

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Dennis J Horvath

2012-01-01

Full Text Available Urinary tract infections (UTIs represent one of the most commonly acquired diseases among the general population as well as hospital in-patients, yet remain difficult to effectively and consistently treat. High rates of recurrence, anatomic abnormalities, and functional disturbances of the urinary tract all contribute to the difficulty in management of these infections. However, recent advances reveal important molecular and genetic factors that contribute to bacterial invasion and persistence in the urinary tract, particularly for the most common causative agent, uropathogenic Escherichia coli. Recent studies using animal models of experimental UTIs have recently provided mechanistic insight into the clinical observations that question the effectiveness of antibiotic therapy in treatment. Ultimately, continuing research will be necessary to identify the best targets for effective treatment of this costly and widespread infectious disease.

[Urinary incontinence in pregnancy and in puerperium: 3 months follow-up after delivery].

Science.gov (United States)

Granese, R; Adile, B

2008-02-01

The aim of this clinic prospective study was to point out the predisposing risk factors for the development of urinary incontinence during pregnancy and postpartum and to understand how to prevent the symptomatology. Sixty seven primipara women at 32 weeks of pregnancy and 3 months after the delivery, were studied through an urogynecological work-up and a questionnaire on the main urinary symptoms. At 32 weeks of pregnancy, 27 patients (40.29%) were affected by stress urinary incontinence (SUI) of type I and 22 (32.83%) by urge incontinence. Three months after delivery, it was observed SUI of type I in 8 patients (15.68%), SUI of type II in 9 patients (17.64%), SUI of type II and II degree cystouretrocele in 3 patients (5.8%) and urge incontinence in 14 patients (27.45%). The most frequent risk factors that were tracked down were: a vaginal delivery, with a prolonged labour, and the episiotomy. We didn't find either substantial changes in the weight between patients continent and incontinent or correlations with the patients' age or with the weight of the foetus and the symptomatology reported. It is important to understand the beginning of the urinary symptoms in the pregnant women, to prevent the worsening of it. It is required, however, a long term follow-up on our patients to verify if the urinary incontinence persists or disappears by the time is needed.

[Urinary tract infection in pregnancy].

Science.gov (United States)

Herráiz, Miguel Angel; Hernández, Antonio; Asenjo, Eloy; Herráiz, Ignacio

2005-12-01

Urinary tract infections, asymptomatic bacteriuria (AB), acute cystitis (AC) and acute pyelonephritis (AP), are favored by the morphological and functional changes involved in pregnancy. AB increases the risk of preterm labor, low birth weight and AP. AB should be detected by uroculture (other methods are not sufficiently effective) and treated early. Approximately 80% of cases are caused by Escherichia coli. The risks and effectiveness of the distinct antibiotic regimens should be evaluated: fosfomycin trometamol in monotherapy or as short course therapy is safe and effective for the treatment of AB and AC. AP is the most frequent cause of hospital admission for medical reasons in pregnant women and can lead to complications in 10% of cases, putting the lives of the mother and fetus at risk. Currently outpatient treatment of AP is recommended in selected cases. Adequate follow-up of pregnant women with urinary tract infections is required due to frequent recurrence.

Epidemiology of urinary tract infections in Hiroshima

Energy Technology Data Exchange (ETDEWEB)

Freedman, L R; Phair, J P; Seki, Masafumi; Hamilton, H B; Nefzger, M D

1964-08-19

The present study was conducted at ABCC on a sample of Hiroshima residents systematically seleced for determining the influence on general health status of exposure to the atomic bomb of 1945. A survey for urinary infections was taken on persons in the sample examined in the ABCC clinic over a 1-year period: approximately 3000 women and 2000 men. The purpose of the study was to determine the prevalence of urinary infection and to study the relation between bacteriuria and various aspects of the general examination, particularly blood pressure. In addition, the rates of urinary tract infection in the clinic were compared with the rates of chronic pyelonephritis at autopsy. Results showed that infections were much more common in women than in men and rose with age in both sexes. The greatest increase in the prevalence was found in women age 60 years and over was due to coliform bacteria in all but a few instances. There was no difference in hematuria, glycosuria, diabetes, serum cholesterol, blood groups, electrocardiograms, audiometry, vibrometry, hemoglobin levels or height-weight ratios. Blood pressure is higher in infected women as compared with noninfected women and the finding of higher rates for cardiac enlargement suggests that this small difference in blood pressures may have biological significance. However, the data do not permit a conclusion as to whether the urinary infections were responsible for the higher blood pressure levels, or whether the higher blood pressure levels increased the frequency of detectable infection. The difference between the clinical rates of urinary infection in men and women, and the pathological diagnosis of pyelonephritis in the same population, supports a previous suggestion that much of what is called pyelonephritis at autopsy is not due to urinary tract infection. 27 references, 2 figures, 10 tables.

Inverse probability of treatment-weighted competing risks analysis: an application on long-term risk of urinary adverse events after prostate cancer treatments.

Science.gov (United States)

Bolch, Charlotte A; Chu, Haitao; Jarosek, Stephanie; Cole, Stephen R; Elliott, Sean; Virnig, Beth

2017-07-10

To illustrate the 10-year risks of urinary adverse events (UAEs) among men diagnosed with prostate cancer and treated with different types of therapy, accounting for the competing risk of death. Prostate cancer is the second most common malignancy among adult males in the United States. Few studies have reported the long-term post-treatment risk of UAEs and those that have, have not appropriately accounted for competing deaths. This paper conducts an inverse probability of treatment (IPT) weighted competing risks analysis to estimate the effects of different prostate cancer treatments on the risk of UAE, using a matched-cohort of prostate cancer/non-cancer control patients from the Surveillance, Epidemiology and End Results (SEER) Medicare database. Study dataset included men age 66 years or older that are 83% white and had a median follow-up time of 4.14 years. Patients that underwent combination radical prostatectomy and external beam radiotherapy experienced the highest risk of UAE (IPT-weighted competing risks: HR 3.65 with 95% CI (3.28, 4.07); 10-yr. cumulative incidence = 36.5%). Findings suggest that IPT-weighted competing risks analysis provides an accurate estimator of the cumulative incidence of UAE taking into account the competing deaths as well as measured confounding bias.

Urinary Tract Health

Science.gov (United States)

... related to the urinary tract health of women: Urinary Tract Infections (UTIs) and Urinary Incontinence (UI). For information on a range of urinary tract health issues for women, men, and children, visit the National Kidney and Urologic Diseases Information ...

Molecular Weights of Bovine and Porcine Heparin Samples: Comparison of Chromatographic Methods and Results of a Collaborative Survey

Directory of Open Access Journals (Sweden)

Sabrina Bertini

2017-07-01

Full Text Available In a collaborative study involving six laboratories in the USA, Europe, and India the molecular weight distributions of a panel of heparin sodium samples were determined, in order to compare heparin sodium of bovine intestinal origin with that of bovine lung and porcine intestinal origin. Porcine samples met the current criteria as laid out in the USP Heparin Sodium monograph. Bovine lung heparin samples had consistently lower average molecular weights. Bovine intestinal heparin was variable in molecular weight; some samples fell below the USP limits, some fell within these limits and others fell above the upper limits. These data will inform the establishment of pharmacopeial acceptance criteria for heparin sodium derived from bovine intestinal mucosa. The method for MW determination as described in the USP monograph uses a single, broad standard calibrant to characterize the chromatographic profile of heparin sodium on high-resolution silica-based GPC columns. These columns may be short-lived in some laboratories. Using the panel of samples described above, methods based on the use of robust polymer-based columns have been developed. In addition to the use of the USP’s broad standard calibrant for heparin sodium with these columns, a set of conditions have been devised that allow light-scattering detected molecular weight characterization of heparin sodium, giving results that agree well with the monograph method. These findings may facilitate the validation of variant chromatographic methods with some practical advantages over the USP monograph method.

Molecular Weights of Bovine and Porcine Heparin Samples: Comparison of Chromatographic Methods and Results of a Collaborative Survey.

Science.gov (United States)

Bertini, Sabrina; Risi, Giulia; Guerrini, Marco; Carrick, Kevin; Szajek, Anita Y; Mulloy, Barbara

2017-07-19

In a collaborative study involving six laboratories in the USA, Europe, and India the molecular weight distributions of a panel of heparin sodium samples were determined, in order to compare heparin sodium of bovine intestinal origin with that of bovine lung and porcine intestinal origin. Porcine samples met the current criteria as laid out in the USP Heparin Sodium monograph. Bovine lung heparin samples had consistently lower average molecular weights. Bovine intestinal heparin was variable in molecular weight; some samples fell below the USP limits, some fell within these limits and others fell above the upper limits. These data will inform the establishment of pharmacopeial acceptance criteria for heparin sodium derived from bovine intestinal mucosa. The method for MW determination as described in the USP monograph uses a single, broad standard calibrant to characterize the chromatographic profile of heparin sodium on high-resolution silica-based GPC columns. These columns may be short-lived in some laboratories. Using the panel of samples described above, methods based on the use of robust polymer-based columns have been developed. In addition to the use of the USP's broad standard calibrant for heparin sodium with these columns, a set of conditions have been devised that allow light-scattering detected molecular weight characterization of heparin sodium, giving results that agree well with the monograph method. These findings may facilitate the validation of variant chromatographic methods with some practical advantages over the USP monograph method.

[Effects of excess nicotinic acid on growth and the urinary excretion of B-group vitamins and the metabolism of tryptophan in weaning rats].

Science.gov (United States)

Fukuwatari, Tsutomu; Kurata, Kaori; Shibata, Katsumi

2009-04-01

To determine the tolerable upper intake level of nicotinic acid in humans, we investigated the effects of excess nicotinic acid administration on body weight gain, food intake, and urinary excretion of water-soluble vitamins and the metabolism of tryptophan in weaning rats. The weaning rats were freely fed a niacin-free 20% casein diet (control diet) or the same diet with 0.1%, 0.3% or 0.5% nicotinic acid for 23 days. The excess nicotinic acid intake did not affect body weight gain, food intake, serotonin contents in the brain, stomach and small intestine, or the urinary excretions of water-soluble vitamins. Although excess nicotinic acid did not affect the upper part of the tryptophan-nicotinamide pathway, 0.5% nicotinic acid diet increased the urinary excretion of quinolinic acid. The diet containing more than 0.3% nicotinic acid also increased the urinary excretion of nicotinic acid, which is usually below the limit of detection. As determined from the results of body weight gain and food intake as indices for apparent adverse effects, the no-observed-adverse-effect-level (NOAEL) for nicotinic acid was 0.5% in diet, corresponding to 450 mg/kg body weight/day. As judged from in increase of urinary quinolinic acid and nicotinic acid as indices of metabolic change, NOAEL was 0.1% in diet, corresponding to 90 mg/kg body weight/day, and the lowest-observed-adverse-effect-level (LOAEL) was 0.3% in diet, corresponding to 270 mg/kg body weight/day.

Three-site mechanism and molecular weight: Time dependency in liquid propylene batch polymerization using a MgCl2-supported Ziegler-Natta catalyst

NARCIS (Netherlands)

Shimizu, Fumihiko; Pater, J.T.M.; Weickert, G.

2001-01-01

This article demonstrates that the molecular weight of propylene homopolymer decreases with time, and that the molecular weight distribution (MWD) narrows when a highly active MgCl2-supported catalyst is used in a liquid pool polymerization at constant H2 concentration and temperature. To track the

Study of effect of gamma radiation on molecular weight and mechanical properties of PHB and PHNV

International Nuclear Information System (INIS)

Fechine, Guilhermino J.M.; Terence, Mauro C.; Rabello, M.S.; Willen, Renate M.R.

2011-01-01

The effect of gamma radiation on molecular weight and mechanical properties (tensile and flexural) of PHB and PHBV samples was investigated. The values of stress and strain at the break point for both mechanical properties indicated that scission molecular reactions were predominant in PHB and PHBV samples submitted to gamma radiation. These results were confirmed by Size Exclusion Chromatography (SEC) analysis. (author)

High molecular weight hyaluronan mediates the cancer resistance of the naked mole-rat

Science.gov (United States)

Tian, Xiao; Azpurua, Jorge; Hine, Christopher; Vaidya, Amita; Myakishev-Rempel, Max; Ablaeva, Julia; Mao, Zhiyong; Nevo, Eviatar; Gorbunova, Vera; Seluanov, Andrei

2013-01-01

The naked mole-rat displays exceptional longevity, with a maximum lifespan exceeding 30 years1–3. This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole-rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years4,5. In addition to their longevity, naked mole-rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single incidence of cancer2,6. Here we identify a mechanism responsible for the naked mole-rat’s cancer resistance. We found that naked mole-rat fibroblasts secrete extremely high molecular weight hyaluronan (HA), which is over five times larger than human or mouse HA. This high molecular weight HA accumulates abundantly in naked mole rat tissues due to the decreased activity of HA-degrading enzymes and a unique sequence of hyaluronan synthase 2 (HAS2). Furthermore, the naked mole-rat cells are more sensitive to HA signaling, as the naked mole rat cells have a higher affinity to HA than the mouse or human cells. Perturbation of the signaling pathways sufficient for malignant transformation of mouse fibroblasts fails to transform naked mole-rat cells. However, once high molecular weight HA is removed by either knocking down HAS2 or overexpressing the HA-degrading enzyme, Hyal2, naked mole-rat cells become susceptible to malignant transformation and readily form tumors in mice. We speculate that naked mole-rats have evolved a higher concentration of HA in the skin to provide skin elasticity needed for life in underground tunnels. This trait may have then been co-opted to provide cancer resistance and longevity to this species. PMID:23783513

Differential Modulation of Cellular Bioenergetics by Poly(L-lysine)s of Different Molecular Weights

DEFF Research Database (Denmark)

Hall, Arnaldur; Wu, Lin-Ping; Parhamifar, Ladan

2015-01-01

Poly(L-lysine)s (PLLs), and related derivatives, have received considerable attention as nonviral vectors. High molecular weight PLLs (H-PLLs) are superior transfectants compared with low Mw PLLs (L-PLLs), but suggested to be more cytotoxic. Through a pan-integrated metabolomic approach using Sea...

Polyacrylamide molecular weight and phosphogypsum effects on infiltration and erosion in semi-arid soils

Science.gov (United States)

Seal formation at the surface of semi-arid soils during rainstorms reduces soil infiltration rate (IR) and causes runoff and erosion. Surface application of dry anionic polyacrylamide (PAM) with high molecular weight (MW) has been found to be effective in stabilizing soil aggregates, and decreasing ...

Nanometer size wear debris generated from ultra high molecular weight polyethylene in vivo

Czech Academy of Sciences Publication Activity Database

Lapčíková, Monika; Šlouf, Miroslav; Dybal, Jiří; Zolotarevova, E.; Entlicher, G.; Pokorný, D.; Gallo, J.; Sosna, A.

2009-01-01

Roč. 266, 1-2 (2009), s. 349-355 ISSN 0043-1648 R&D Projects: GA MŠk 2B06096 Institutional research plan: CEZ:AV0Z40500505 Keywords : ultra high molecular weight polyethylene * nanometer size wear debris * morphology of wear particles Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.771, year: 2009

Artificial urinary sphincter implantation: an important component of complex surgery for urinary tract reconstruction in patients with refractory urinary incontinence.

Science.gov (United States)

Zhang, Fan; Liao, Limin

2018-01-08

We review our outcomes and experience of artificial urinary sphincter implantation for patients with refractory urinary incontinence from different causes. Between April 2002 and May 2017, a total of 32 patients (median age, 40.8 years) with urinary incontinence had undergone artificial urinary sphincter placement during urinary tract reconstruction. Eighteen patients (56.3%) were urethral injuries associated urinary incontinence, 9 (28.1%) had neurogenic urinary incontinence and 5 (15.6%) were post-prostatectomy incontinence. Necessary surgeries were conducted before artificial urinary sphincter placement as staged procedures, including urethral strictures incision, sphincterotomy, and augmentation cystoplasty. The mean follow-up time was 39 months. At the latest visit, 25 patients (78.1%) maintained the original artificial urinary sphincter. Four patients (12.5%) had artificial urinary sphincter revisions. Explantations were performed in three patients. Twenty-four patients were socially continent, leading to the overall success rate as 75%. The complication rate was 28.1%; including infections (n = 4), erosions (n = 4), and mechanical failure (n = 1). The impact of urinary incontinence on the quality of life measured by the visual analogue scale dropped from 7.0 ± 1.2 to 2.2 ± 1.5 (P urinary sphincter implantation in our center are unique, and the procedure is an effective treatment as a part of urinary tract reconstruction in complicated urinary incontinence cases with complex etiology.

Structure and allosteric effects of low-molecular-weight activators on the protein kinase PDK1

DEFF Research Database (Denmark)

Hindie, Valerie; Stroba, Adriana; Zhang, Hua

2009-01-01

-dependent activation of AGC kinases. The AGC kinase PDK1 is activated by the docking of a phosphorylated motif from substrates. Here we present the crystallography of PDK1 bound to a rationally developed low-molecular-weight activator and describe the conformational changes induced by small compounds in the crystal...... molecular details of the allosteric changes induced by small compounds that trigger the activation of PDK1 through mimicry of phosphorylation-dependent conformational changes....

Functional Comparison for Lipid Metabolism and Intestinal and Fecal Microflora Enzyme Activities between Low Molecular Weight Chitosan and Chitosan Oligosaccharide in High-Fat-Diet-Fed Rats.

Science.gov (United States)

Chiu, Chen-Yuan; Feng, Shih-An; Liu, Shing-Hwa; Chiang, Meng-Tsan

2017-07-24

The present study investigated and compared the regulatory effects on the lipid-related metabolism and intestinal disaccharidase/fecal bacterial enzyme activities between low molecular weight chitosan and chitosan oligosaccharide in high-fat-diet-fed rats. Diet supplementation of low molecular weight chitosan showed greater efficiency than chitosan oligosaccharide in suppressing the increased weights in body and in liver and adipose tissues of high-fat-diet-fed rats. Supplementation of low molecular weight chitosan also showed a greater improvement than chitosan oligosaccharide in imbalance of plasma, hepatic, and fecal lipid profiles, and intestinal disaccharidase activities in high-fat-diet-fed rats. Moreover, both low molecular weight chitosan and chitosan oligosaccharide significantly decreased the fecal microflora mucinase and β-glucuronidase activities in high-fat-diet-fed rats. These results suggest that low molecular weight chitosan exerts a greater positive improvement than chitosan oligosaccharide in lipid metabolism and intestinal disaccharidase activity in high-fat-diet-induced obese rats.

Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro

Energy Technology Data Exchange (ETDEWEB)

Zhao, Ningbo, E-mail: curl-zhao@163.com; Wang, Xin, E-mail: 394041230@qq.com; Qin, Lei, E-mail: qinlei30@126.com; Guo, Zhengze, E-mail: zhzeguo@163.com; Li, Dehua, E-mail: lidehuafmmu@163.com

2015-09-25

Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased by increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation. - Highlights: • Effect of hyaluronan on cell proliferation and differentiation is evaluated in vitro. • Hyaluronan of low molecular weight increases cell proliferation. • Hyaluronan of high molecular weight promotes cell osteogenic differentiation. • Molecular weight and concentration of hyaluronan show interactive effect.

Dependence of negative muon depolarization on molecular weight and temperature in organic compounds

International Nuclear Information System (INIS)

Djuraev, A.A.; Evseev, V.S.; Obukhov, Yu.V.; Roganov, V.S.

2009-01-01

An atomic capture of negative muons in the aliphatic spirit series, the dependence of muon rest polarization on the molecular weight of spirit have been studied. The temperature dependence of depolarization in benzole and styrene has been obtained. The results on depolarization are being interpreted basing on notions about chemical interactions of mesic atoms in organic compounds. (author)

Detection of high molecular weight proteins by MALDI imaging mass spectrometry.

Science.gov (United States)

Mainini, Veronica; Bovo, Giorgio; Chinello, Clizia; Gianazza, Erica; Grasso, Marco; Cattoretti, Giorgio; Magni, Fulvio

2013-06-01

MALDI imaging mass spectrometry (IMS) is a unique technology to explore the spatial distribution of biomolecules directly on tissues. It allows the in situ investigation of a large number of small proteins and peptides. Detection of high molecular weight proteins through MALDI IMS still represents an important challenge, as it would allow the direct investigation of the distribution of more proteins involved in biological processes, such as cytokines, enzymes, neuropeptide precursors and receptors. In this work we compare the traditional method performed with sinapinic acid with a comparable protocol using ferulic acid as the matrix. Data show a remarkable increase of signal acquisition in the mass range of 20k to 150k Th. Moreover, we report molecular images of biomolecules above 70k Th, demonstrating the possibility of expanding the application of this technology both in clinical investigations and basic science.

Phosphorus release from phosphate rock and iron phosphate by low-molecular-weight organic acids.

Science.gov (United States)

Xu, Ren-kou; Zhu, Yong-guan; Chittleborough, David

2004-01-01

Low-molecular-weight(LMW) organic acids widely exist in soils, particularly in the rhizosphere. A series of batch experiments were carried out to investigate the phosphorus release from rock phosphate and iron phosphate by low-molecular-weight organic acids. Results showed that citric acid had the highest capacity to solubilize P from both rock and iron phosphate. P solubilization from rock phosphate and iron phosphate resulted in net proton consumption. P release from rock phosphate was positively correlated with the pKa values. P release from iron phosphate was positively correlated with Fe-organic acid stability constants except for aromatic acids, but was notcorrelated with pKa. Increase in the concentrations of organic acids enhanced P solubilization from both rock and iron phosphate almost linearly. Addition of phenolic compounds further increased the P release from iron phosphate. Initial solution pH had much more substantial effect on P release from rock phosphate than from iron phosphate.

Propensity-Weighted Comparison of Long-Term Risk of Urinary Adverse Events in Elderly Women Treated For Cervical Cancer

International Nuclear Information System (INIS)

Elliott, Sean P.; Fan, Yunhua; Jarosek, Stephanie; Chu, Haitao; Downs, Levi; Dusenbery, Kathryn; Geller, Melissa A.; Virnig, Beth A.

2015-01-01

Purpose: Cervical cancer treatment is associated with a risk of urinary adverse events (UAEs) such as ureteral stricture and vesicovaginal fistula. We sought to measure the long-term UAE risk after surgery and radiation therapy (RT), with confounding controlled through propensity-weighted models. Methods and Materials: From the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we identified women ≥66 years old with nonmetastatic cervical cancer treated with simple surgery (SS), radical hysterectomy (RH), external beam RT plus brachytherapy (EBRT+BT), or RT+surgery. We matched them to noncancer controls 1:3. Differences in demographic and cancer characteristics were balanced by propensity weighting. Grade 3 to 4 UAEs were identified by diagnosis codes plus treatment codes. Cumulative incidence was measured using Kaplan-Meier methods. The hazard associated with different cancer treatments was compared using Cox models. Results: UAEs occurred in 272 of 1808 cases (17%) and 222 of 5424 (4%) controls; most (62%) were ureteral strictures. The raw cumulative incidence of UAEs was highest in advanced cancers. UAEs occurred in 31% of patients after EBRT+BT, 25% of patients after RT+surgery, and 15% of patients after RH; however, after propensity weighting, the incidence was similar. In adjusted Cox models (reference = controls), the UAE risk was highest after RT+surgery (hazard ratio [HR], 5.07; 95% confidence interval [CI], 2.32-11.07), followed by EBRT+BT (HR, 3.33; 95% CI, 1.45-7.65), RH (HR, 3.65; 95% CI, 1.41-9.46) and SS (HR, 0.99; 95% CI, 0.32-3.01). The higher risk after RT+surgery versus EBRT+BT was statistically significant, whereas, EBRT+BT and RH were not significantly different from each other. Conclusions: UAEs are common after cervical cancer treatment, particularly in patients with advanced cancers. UAEs are more common after RT, but these women tend to have the advanced cancers. After propensity weighting, the risk after RT was similar

Measurement of low molecular weight silicon AMC to protect UV optics in photo-lithography environments

Science.gov (United States)

Lobert, Jürgen M.; Miller, Charles M.; Grayfer, Anatoly; Tivin, Anne M.

2009-03-01

A new analytical method for semiconductor-specific applications is presented for the accurate measurement of low molecular weight, silicon-containing, organic compounds TMS, HMDSO and D3. Low molecular weight / low boiling point silicon-containing compounds are not captured for extended periods of time by traditional chemical filters but have the same potential to degrade exposure tool optical surfaces as their high molecular weight counterparts. Likewise, we show that capturing these compounds on sample traps that are commonly used for organic AMC analysis does not work for various reasons. Using the analytical method described here, TMS, HMDSO and D3 can be measured artifact-free, with at least a 50:1 peak-to-noise ratio at the method detection limit, determined through the Hubaux-Vos method and satisfying a conservative 99% statistical confidence. Method detection limits for the compounds are 1-6 ppt in air. We present calibration curve, capacity, capture efficiency, break-through and repeatability data to demonstrate robustness of method. Seventy-one real-world samples from 26 projects taken in several fab environments show that TMS is found in concentrations 100 times higher than those of HMDSO and D3. All compounds are found in all environments in concentrations ranging from zero to 12 ppm, but most concentrations were below 50 ppb. All compounds are noticeably higher in litho-bays than in sub-fabs and we found all three compounds inside of two exposure tools, suggesting cleanroom and/or tool-internal contamination sources.

Effect of gamma irradiation on the friction and wear of ultrahigh molecular weight polyethylene

Science.gov (United States)

Jones, W. R.; Hady, W. F.; Crugnola, A.

1981-01-01

The effect of sterilization gamma irradiation on the friction and wear properties of ultrahigh molecular weight polyethylene (UHMWPE) sliding against stainless steel 316L in dry air at 23 C is investigated, the results to be used in the development of artificial joints which are to surgically replace diseased human joints. A pin-on-disk sliding friction apparatus is used, a constant sliding speed in the range 0.061-0.27 m/s is maintained, a normal load of 1 kgf is applied with dead weight, and the irradiation dose levels are: 0, 2.5, and 5.0 Mrad. Wear and friction data and conditions for each of the ten tests are summarized, and include: (1) wear volume as a function of the sliding distance for the irradiation levels, (2) incremental wear rate, and (3) coefficient of friction as a function of the sliding distance. It is shown that (1) the friction and wear properties of UHMWPE are not significantly changed by the irradiation doses of 2.5 and 5.0 Mrad, (2) the irradiation increases the amount of insoluble gel as well as the amount of low molecular weight material, and (3) after run-in the wear rate is either steady or gradually decreases as a function of the sliding distance.

Urinary incontinence in women in relation to occupational status.

Science.gov (United States)

Kim, Yoonjung; Kwak, Yeunhee

2017-01-01

Through this cross-sectional study the authors explore urinary incontinence in women in relation to occupational status and environment. Data from the fourth Korea National Health and Nutrition Examination Survey (2008-2009) were used (n = 5,928) excluding those aged under 19 or over 65 years, male, with renal disease, and with missing data. Urinary incontinence was prevalent in working women. Compared to unemployed women, the adjusted odds ratio (95% confidence intervals) for women working in services/sales was 1.62 (1.21-2.19); for paid workers was 1.81 (1.20-2.73); and for self-employed workers was 1.46 (1.05-2.03). Compared to unemployed women, the adjusted odds ratio for working women with a daytime work schedule was 2.14 (1.18-3.87), while for those with evening work schedules, it was 1.35 (1.05-1.74). Urinary incontinence was significantly associated with various occupational environments: an unclean and uncomfortable workplace, dangerous job and probability of accidents, feeling pressed for time, awkward position for long periods, and carrying heavy weights. These findings suggest that urinary incontinence was prevalent in working women and was associated with occupational status and working environment. Therefore, improving occupational status and environment for working women-such as modifying the working schedule, posture, and workplace atmosphere-are needed to prevent urinary incontinence.

Yield, Esterification Degree and Molecular Weight Evaluation of Pectins Isolated from Orange and Grapefruit Peels under Different Conditions

Science.gov (United States)

Sayah, Mohamed Yassine; Chabir, Rachida; Benyahia, Hamid; Rodi Kandri, Youssef; Ouazzani Chahdi, Fouad; Touzani, Hanan; Errachidi, Faouzi

2016-01-01

Orange (Citrus sinensis) and grapefruit (Citrus paradise) peels were used as a source of pectin, which was extracted under different conditions. The peels are used under two states: fresh and residual (after essential oil extraction). Organic acid (citric acid) and mineral acid (sulfuric acid) were used in the pectin extraction. The aim of this study is the evaluation the effect of extraction conditions on pectin yield, degree of esterification “DE” and on molecular weight “Mw”. Results showed that the pectin yield was higher using the residual peels. Moreover, both peels allow the obtainment of a high methoxyl pectin with DE >50%. The molecular weight was calculated using Mark-Houwink-Sakurada equation which describes its relationship with intrinsic viscosity. This later was determined using four equations; Huggins equation, kramer, Schulz-Blaschke and Martin equation. The molecular weight varied from 1.538 x1005 to 2.47x1005 g/mol for grapefruit pectin and from 1.639 x1005 to 2.471 x1005 g/mol for orange pectin. PMID:27644093

Relationship of molecular weight distribution profile of unreduced gluten protein extracts with quality characteristics of bread.

Science.gov (United States)

Chaudhary, Nisha; Dangi, Priya; Khatkar, B S

2016-11-01

A statistical correlation was established among the molecular weight distribution patterns of unreduced gluten proteins and physicochemical, rheological and bread-making quality characteristics of wheat varieties. Size exclusion chromatography fractionated the gluten proteins apparently into five peaks. Peak I signified glutenins (30-130kDa), peak II as gliadins (20-55kDa), peak III as very low molecular weight monomeric gliadins (10-28kDa), peak IV and V, collectively, as albumins and globulins (bread loaf volume (r=0.848(∗∗)); however, peak II had negative (r=-0.818(∗∗)) impact. Bread firmness increased with increment in peak II (r=0.625(∗∗)), and decreased with accretion in peak I (r=-0.623(∗∗)). Copyright © 2016 Elsevier Ltd. All rights reserved.

Urinary Tract Infection (UTI)

Science.gov (United States)

... Home A-Z Health Topics Urinary tract infections Urinary tract infections > A-Z Health Topics Urinary tract infections (PDF, ... Embed Subscribe To receive Publications email updates Submit Urinary tract infections Urinary tract infections (UTIs) are most often caused ...

Effect of electron beam radiation on the structure and mechanical properties of ultra high molecular weight polyethylene fibers

International Nuclear Information System (INIS)

Li Shujun; Sun Weijun; Liu Xiuju; Gao Yongzhong; Li Huisheng

1998-01-01

Ultra high molecular weight polyethylene fibers have been crosslinked by electron beam. The structure and mechanical properties of them have been investigated in different irradiation atmospheres. The obtained results show that the gel content and crosslinking density increase with the increase of dose, the swelling ratio and average molecular weight of crosslinked net decrease with the increase of dose, the tensile strength and failure elongation decrease with the increase of dose, the tensile modulus increases with the increase of dose. When the samples are irradiated in air, vacuum and acetylene atmospheres, the effect of irradiation in acetylene atmosphere is best

Effects of molecular weight on the glass transition temperature in Durolon polycarbonate

International Nuclear Information System (INIS)

Miranda, Adelina; Sciani, Valdir

1995-01-01

The effect of variation of the dose rate on degradation mechanism of PC Durolon irradiated with gamma rays was determined trough out intrinsic viscosity and thermal analysis of DSC-type measurements. The results showed a linear relationship between the glass transition temperature and the viscosimetric average molecular weight. From the results it's shown that with an increased of the dose rate it also increases the degradation of the material. (author). 12 refs., 3 figs

MALDI-TOF mass spectrometry analysis of small molecular weight compounds (under 10 KDa) as biomarkers of rat hearts undergoing arecoline challenge.

Science.gov (United States)

Chen, Tung-Sheng; Chang, Mu-Hsin; Kuo, Wei-Wen; Lin, Yueh-Min; Yeh, Yu-Lan; Day, Cecilia Hsuan; Lin, Chien-Chung; Tsai, Fuu-Jen; Tsai, Chang-Hai; Huang, Chih-Yang

2013-04-01

Statistical and clinical reports indicate that betel nut chewing is strongly associated with progression of oral cancer because some ingredients in betel nuts are potential cancer promoters, especially arecoline. Early diagnosis for cancer biomarkers is the best strategy for prevention of cancer progression. Several methods are suggested for investigating cancer biomarkers. Among these methods, gel-based proteomics approach is the most powerful and recommended tool for investigating biomarkers due to its high-throughput. However, this proteomics approach is not suitable for screening biomarkers with molecular weight under 10 KDa because of the characteristics of gel electrophoresis. This study investigated biomarkers with molecular weight under 10 KDa in rats with arecoline challenge. The centrifuging vials with membrane (10 KDa molecular weight cut-off) played a crucial role in this study. After centrifuging, the filtrate (containing compounds with molecular weight under 10 KDa) was collected and spotted on a sample plate for MALDI-TOF mass spectrometry analysis. Compared to control, three extra peaks (m/z values were 1553.1611, 1668.2097 and 1740.1832, respectively) were found in sera and two extra peaks were found in heart tissue samples (408.9719 and 524.9961, respectively). These small compounds should play important roles and may be potential biomarker candidates in rats with arecoline. This study successfully reports a mass-based method for investigating biomarker candidates with small molecular weight in different types of sample (including serum and tissue). In addition, this reported method is more time-efficient (1 working day) than gel-based proteomics approach (5~7 working days).

Influence of molecular weight of DNA on the determination of anti-DNA antibodies in systemic lupus erythematosus (SLE) sera by radioimmunoassay

Energy Technology Data Exchange (ETDEWEB)

Geisert, M; Heicke, B; Metzmann, E; Zahn, R K

1975-04-01

Using a radioimmunoassay (RIA) based on the Farr technique with radioactively labeled /sup 3/H-DNA for quantitative measurements of anti-DNA antibodies in sera of patients with systemic lupus erythematosus (SLE), the influence of molecular weight of DNA (ranging from 0.1 x 10/sup 6/ to 22.0 x 10/sup 6/ daltons) on binding and precipitation in this system has been investigated. Comparing our results with mathematical models it follows that one antibody molecule is fixed on the average to a statistical DNA segment of 2 x 10/sup 6/ to 4 x 10/sup 6/ daltons. Furthermore binding capacity of the DNA was found to be independent of the molecular weight, as demonstrated in a double label experiment using /sup 14/C and /sup 3/H-labeled DNA of different size. However, the amount of radioactivity precipitated was found to depend on the molecular weight of the labeled DNA following a non-linear function. It was calculated that a minimal ratio of fixed antibody molecules per a certain size of DNA was necessary for precipitation. The mathematical treatment of the observed non-linear precipitation dependence will be discussed using various statistical models. The results indicate that the quantitative measurements of anti-DNA antibodies with the Farr technique e.g., for diagnosis and control of SLE in clinical immunology is highly dependent on the molecular weight of the labeled DNA used in the assay system and reliable results are only obtained with DNA of a sufficiently high molecular weight. (auth)

Hypertension increases urinary excretion of immunoglobulin G, ceruloplasmin and transferrin in normoalbuminuric patients with type 2 diabetes mellitus.

Science.gov (United States)

Ohara, Nobumasa; Hanyu, Osamu; Hirayama, Satoshi; Nakagawa, Osamu; Aizawa, Yoshifusa; Ito, Seiki; Sone, Hirohito

2014-02-01

Increased urinary excretion of certain plasma proteins, such as immunoglobulin G (IgG), ceruloplasmin and transferrin, with different molecular radii of 55 Å or less and different isoelectric points have been reported to precede development of microalbuminuria in patients who have diabetes mellitus with hypertension. We examined how hypertension affects these urinary proteins in a diabetic state. Excretion of IgG, ceruloplasmin, transferrin, albumin, α2-macroglobulin with a large molecular radius of 88 Å and N-acetylglucosaminidase in first-morning urine samples were measured in normoalbuminuric patients (urinary albumin-to-creatinine ratio hypertension and nondiabetes mellitus (group hypertension, n = 32), type 2 diabetes mellitus and normotension (group diabetes mellitus, n = 52) and type 2 diabetes mellitus and hypertension (group Both, n =45), and in age-matched controls (n = 72). Urinary IgG, ceruloplasmin, transferrin, albumin and N-acetylglucosaminidase and estimated glomerular filtration rate (eGFR) were significantly elevated in groups diabetes mellitus and Both compared with controls. Furthermore, urinary IgG, ceruloplasmin and transferrin in group Both were significantly higher than those in group diabetes mellitus. These exhibited a positive and relatively strong association with eGFR compared with controls. No significant difference in urinary albumin or N-acetylglucosaminidase was found between the two diabetic groups. In contrast, group hypertension had elevated urinary transferrin without any changes in the other compounds. Urinary α2-macroglobulin did not differ among the four groups. These findings suggest that normoalbuminuric diabetic patients without hypertension have both glomerular hemodynamic changes such as increased intraglomerular hydraulic pressure and altered proximal tubules, and that hypertension increases intraglomerular hydraulic pressure. Increased urinary IgG, ceruloplasmin and transferrin may reflect an increase in

Diminished creatinine clearance in anorexia nervosa: reversal with weight gain.

OpenAIRE

Boag, F; Weerakoon, J; Ginsburg, J; Havard, C W; Dandona, P

1985-01-01

To assess whether patients with anorexia nervosa have abnormalities in creatinine clearance, we measured plasma creatinine concentration, urinary creatinine excretion, and creatinine clearance in 10 patients with anorexia nervosa before and during treatment. Urinary creatinine excretion and creatinine clearance were diminished in all patients. Nine patients had significant decreases in their plasma creatinine and creatinine clearance was increased even when corrected for body weight and body ...

Stress Urinary Incontinence in Women With Multiple Sclerosis

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Caroline Massot

2016-09-01

Full Text Available Purpose To report the prevalence and risk factors of stress urinary incontinence (SUI and the prevalence of intrinsic sphincter deficiency in women with multiple sclerosis (MS. Methods We conducted a retrospective study. Female patients with MS, followed for lower urinary tract symptoms (LUTS during a 15-year period were included. Demographic data, MS history, expanded disability status scale (EDSS score at the urodynamic visit, obstetrical past, birth weight, LUTS, and urodynamic findings were collected. SUI was defined as incontinence during cough, or any effort. A maximum urethral closure pressure less than 30 cm H2O defined intrinsic sphincter deficiency. Results We included 363 women with a mean age of 46.7±10.8 years and a mean disease duration of 12.9±8.7 years. The incidence of relapsing remitting MS, a secondary progressive form, and a primary progressive form was 60.6%, 32.8%, and 6.6%, respectively. The prevalence of SUI was 31.4%. The prevalence of intrinsic sphincter deficiency was 1.4% and 0.8% of these patients had a SUI (P=0.300. In a multivariate analysis, women with a SUI had significantly higher birth weight (P=0.030, a pelvic organ prolapse (P=0.021, urgent urinary incontinence (P=0.006, a lower EDSS score (P=0.019, and a weaker containing effort (P<0.001. Conclusions The prevalence of SUI in women with MS was 31.4%. This symptom could affect the quality of life of women with MS.

Urinary catheter - infants

Science.gov (United States)

Bladder catheter - infants; Foley catheter - infants; Urinary catheter - neonatal ... A urinary catheter is a small, soft tube placed in the bladder. This article addresses urinary catheters in babies. WHY IS ...

Impact of Ramadan Intermittent Fasting on Oxidative Stress Measured by Urinary 15-F2t-Isoprostane

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Mo'ez Al-Islam Ezzat Faris

2012-01-01

fast Ramadan were recruited. Urine and serum sampling and anthropometric and dietary assessments were conducted one week before Ramadan (T0, at the end of the third week of Ramadan (T1, and one month after Ramadan (T2. Biochemical measurements included urinary 15FIP, creatinine, and hematological indices. Results revealed that the urinary level of 15FIP measured at T0 was normal, while they showed a significantly (P<0.05 higher level when measured at T1 concomitant with a significant (P<0.05 increase in the body weight and total body fat percent. In conclusion, results suggest that increased body weight is associated with increased lipid peroxidation and oxidative stress, and the impact of RIF on oxidative stress is mediated by the changes in body weight at the end of the month.

Evidence of low molecular weight components in the organic matrix of the reef building coral, Stylophora pistillata.

Science.gov (United States)

Puverel, S; Houlbrèque, F; Tambutté, E; Zoccola, D; Payan, P; Caminiti, N; Tambutté, S; Allemand, D

2007-08-01

Biominerals contain both inorganic and organic components. Organic components are collectively termed the organic matrix, and this matrix has been reported to play a crucial role in mineralization. Several matrix proteins have been characterized in vertebrates, but only a few in invertebrates, primarily in Molluscs and Echinoderms. Methods classically used to extract organic matrix proteins eliminate potential low molecular weight matrix components, since cut-offs ranging from 3.5 to 10 kDa are used to desalt matrix extracts. Consequently, the presence of such components remains unknown and these are never subjected to further analyses. In the present study, we have used microcolonies from the Scleractinian coral Stylophora pistillata to study newly synthesized matrix components by labelling them with 14C-labelled amino acids. Radioactive matrix components were investigated by a method in which both total organic matrix and fractions of matrix below and above 5 kDa were analyzed. Using this method and SDS-PAGE analyses, we were able to detect the presence of low molecular mass matrix components (weight molecules, these probably form the bulk of newly synthesized organic matrix components. Our results suggest that these low molecular weight components may be peptides, which can be involved in the regulation of coral skeleton mineralization.

Improving the Application of High Molecular Weight Biotinylated Dextran Amine for Thalamocortical Projection Tracing in the Rat.

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Xu, Dongsheng; Cui, Jingjing; Wang, Jia; Zhang, Zhiyun; She, Chen; Bai, Wanzhu

2018-04-12

High molecular weight biotinylated dextran amine (BDA) has been used as a highly sensitive neuroanatomical tracer for many decades. Since the quality of its labeling was affected by various factors, here, we provide a refined protocol for the application of high molecular weight BDA for studying optimal neural labeling in the central nervous system. After stereotactic injection of BDA into the ventral posteromedial nucleus (VPM) of the thalamus in the rat through a delicate glass pipette, BDA was stained with fluorescent streptavidin-Alexa (AF) 594 and counterstained with fluorescent Nissl stain AF500/525. On the background of green Nissl staining, the red BDA labeling, including neuronal cell bodies and axonal terminals, was more distinctly demonstrated in the somatosensory cortex. Furthermore, double fluorescent staining for BDA and the calcium-binding protein parvalbumin (PV) was carried out to observe the correlation of BDA labeling and PV-positive interneurons in the cortical target, providing the opportunity to study the local neural circuits and their chemical characteristics. Thus, this refined method is not only suitable for visualizing high quality neural labeling with the high molecular weight BDA through reciprocal neural pathways between the thalamus and cerebral cortex, but also will permit the simultaneous demonstration of other neural markers with fluorescent histochemistry or immunochemistry.

Enhancing Accuracy in Molecular Weight Determination of Highly Heterogeneously Glycosylated Proteins by Native Tandem Mass Spectrometry

NARCIS (Netherlands)

Wang, Guanbo; de Jong, Rob N; van den Bremer, Ewald T J; Parren, Paul W H I; Heck, Albert J R

2017-01-01

The determination of molecular weights (MWs) of heavily glycosylated proteins is seriously hampered by the physicochemical characteristics and heterogeneity of the attached carbohydrates. Glycosylation impacts protein migration during sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis

Resveratrol improves prostate fibrosis during progression of urinary dysfunction in chronic prostatitis.

Science.gov (United States)

He, Yi; Zeng, Hui-Zhi; Yu, Yang; Zhang, Jia-Shu; Duan, Xingping; Zeng, Xiao-Na; Gong, Feng-Tao; Liu, Qi; Yang, Bo

2017-09-01

We investigated whether prostate fibrosis was associated with urinary dysfunction in chronic prostatitis (CP) and whether resveratrol improved urinary dysfunction and the underlying molecular mechanism. Rat model of CP was established via subcutaneous injections of DPT vaccine and subsequently treated with resveratrol. Bladder pressure and volume tests investigated the effect of resveratrol on urinary dysfunction in CP rats. Western blotting and immunohistochemical staining examined the expression level of C-kit/SCF and TGF-β/Wnt/β-catenin. Compared to the control group, the maximum capacity of the bladder, residual urine volume and maximum voiding pressure, the activity of C-kit/SCF and TGF-β/Wnt/β-catenin pathways were increased significantly in the CP group. Resveratrol treatment significantly improved these factors. CP induced significantly prostate fibrosis, which exhibits a close relationship with urinary dysfunction. Resveratrol improved fibrosis, which may be associated with the suppression of C-kit/SCF and TGF-β/Wnt/β-catenin pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

Enhanced hyluronic acid production in Streptococcus zooepidemicus by over expressing HasA and molecular weight control with Niscin and glucose

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Alireza Zakeri

2017-12-01

Full Text Available Hyaluronic acid (HA is a high molecular weight linear polysaccharide, endowed with unique physiological and biological properties. Given its unique properties, HA have unprecedented applications in the fields of medicine and cosmetics. The ever growing demand for HA production is the driving force behind the need for finding and developing novel and amenable sources of the HA producers. Microbial fermentation of Streptococcus zooepidemicus deemed as one the most expeditious and pervasive methods of HA production. Herein, a wild type Streptococcus zooepidemicus, intrinsically expressing high levels of HA, was selected and optimized for HA production. HasA gene was amplified and introduced into the wild type Streptococcus zooepidemicus, under the control of Nisin promoter. The HasA over-expression increased the HA production, while the molecular weight was decreased. In order to compensate for molecular weight loss, the glucose concentration was increased to an optimum amount of 90 g/L. It is hypostatizes that excess glucose would rectify the distribution of the monomers and each HasA molecule would be provided with sufficient amount of substrates to lengthen the HA molecules. Arriving at an improved strain and optimized cultivating condition would pave the way for industrial grade HA production with high quality and quantity. Keywords: Streptococcus zooepidemicus, Hyaluronic acid, HasA, Glucose, Molecular weight

N-linked (N-) glycoproteomics of urinary exosomes. [Corrected].

Science.gov (United States)

Saraswat, Mayank; Joenväära, Sakari; Musante, Luca; Peltoniemi, Hannu; Holthofer, Harry; Renkonen, Risto

2015-02-01

Epithelial cells lining the urinary tract secrete urinary exosomes (40-100 nm) that can be targeted to specific cells modulating their functionality. One potential targeting mechanism is adhesion between vesicle surface glycoproteins and target cells. This makes the glycopeptide analysis of exosomes important. Exosomes reflect the physiological state of the parent cells; therefore, they are a good source of biomarkers for urological and other diseases. Moreover, the urine collection is easy and noninvasive and urinary exosomes give information about renal and systemic organ systems. Accordingly, multiple studies on proteomic characterization of urinary exosomes in health and disease have been published. However, no systematic analysis of their glycoproteomic profile has been carried out to date, whereas a conserved glycan signature has been found for exosomes from urine and other sources including T cell lines and human milk. Here, we have enriched and identified the N-glycopeptides from these vesicles. These enriched N-glycopeptides were solved for their peptide sequence, glycan composition, structure, and glycosylation site using collision-induced dissociation MS/MS (CID-tandem MS) data interpreted by a publicly available software GlycopeptideId. Released glycans from the same sample was also analyzed with MALDI-MS. We have identified the N-glycoproteome of urinary exosomes. In total 126 N-glycopeptides from 51 N-glycosylation sites belonging to 37 glycoproteins were found in our results. The peptide sequences of these N-glycopeptides were identified unambiguously and their glycan composition (for 125 N-glycopeptides) and structures (for 87 N-glycopeptides) were proposed. A corresponding glycomic analysis with released N-glycans was also performed. We identified 66 unique nonmodified N-glycan compositions and in addition 13 sulfated/phosphorylated glycans were also found. This is the first systematic analysis of N-glycoproteome of urinary exosomes. © 2015 by The

Urinary lithiasis and urinary tract malformations in children: A retrospective study of 34 cases

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Jamila Chahed

2011-01-01

Full Text Available Background: Although the association of urinary lithiasis and urinary tract malformation is not rare, their management poses challenges. The aim of this study was to evaluate the relationship between urolithiasis and malformations of the urinary system. There were 34 patients (19 males and 15 females with a mean age of 4.8 years (range, 2 months to 14 years. All patients had urinary lithiasis with a urinary tract malformation. Abdominal pain was the most frequent clinical symptom (38%. Urinary infection was found in 7 patients (21% and macroscopic haematuria was present in 10 patients (29%. The most frequent urinary tract malformations were megaureter (8 cases, uretero-pelvic junction obstruction (7 cases and vesico-ureteric reflux (8 cases, but its malformative origin could not be confirmed. Treatment consisted of lithiasis extraction in 32 cases associated with specific treatment of the uropathy in 27 cases. Postoperative outcome was uneventful in all cases. In fact, urinary lithiasis and urinary tract malformation association is not rare. Indeed, 9-34% of urinary lithiasis are noted to be associated with urinary tract malformation. Positive diagnosis relies specifically on kidney ultrasound, intravenous urography, and urethrocystography. Treatment depends on the type of urinary tract malformation, localisation and size of the urinary lithiasis. Conclusion: In conclusion, urinary lithiasis and urinary tract malformation association is a frequent eventuality. Surgical intervention is the usual mode of treatment.

Mass Spectrometry Imaging of low Molecular Weight Compounds in Garlic (Allium sativum L.) with Gold Nanoparticle Enhanced Target.

Science.gov (United States)

Misiorek, Maria; Sekuła, Justyna; Ruman, Tomasz

2017-11-01

Garlic (Allium sativum) is the subject of many studies due to its numerous beneficial properties. Although compounds of garlic have been studied by various analytical methods, their tissue distributions are still unclear. Mass spectrometry imaging (MSI) appears to be a very powerful tool for the identification of the localisation of compounds within a garlic clove. Visualisation of the spatial distribution of garlic low-molecular weight compounds with nanoparticle-based MSI. Compounds occurring on the cross-section of sprouted garlic has been transferred to gold-nanoparticle enhanced target (AuNPET) by imprinting. The imprint was then subjected to MSI analysis. The results suggest that low molecular weight compounds, such as amino acids, dipeptides, fatty acids, organosulphur and organoselenium compounds are distributed within the garlic clove in a characteristic manner. It can be connected with their biological functions and metabolic properties in the plant. New methodology for the visualisation of low molecular weight compounds allowed a correlation to be made between their spatial distribution within a sprouted garlic clove and their biological function. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Lower Urinary Tract Symptoms and Urinary Incontinence During Pregnancy.

Science.gov (United States)

Balik, Gülşah; Güven, Emine Seda G; Tekin, Yeşim B; Şentürk, Şenol; Kağitci, Mehmet; Üstüner, Işık; Mete Ural, Ülkü; Şahin, Figen K

2016-05-01

Lower urinary tract symptoms (LUTS) can frequently be seen in pregnant women. Pregnancy and delivery have been considered as risk factors in the occurrence of pelvic floor dysfunction and determinants of LUTS. The main associated risk factor is parity. In the present study, we aim to determine the frequency of LUTS and urinary incontinence (UI) during pregnancy and the associated risk factors. This prospective study was carried out in a total of 250 women during their 28- and 40-gestational week checks. The Urinary Distress Inventory-6, the Incontinence Impact Questionnaire-7, and International Consultation on Incontinence Questionnaire-Short Form were used to determine LUTS and its effect on quality of life. The mean age and gestational age of the participants were 29.41 ± 5.70 year (range 18-44) and 35.45 ± 2.98 weeks (range 28-40), respectively. The prevalence of LUTS was 81.6%. The prevalence of UI during pregnancy was 37.2%. Stress urinary incontinence, urge urinary incontinence and mixed urinary incontinence were diagnosed as 15.6, 4.8 and 16.8%, respectively. We found that advanced age, smoking and multiparity were risk factors associated with incontinence. Incontinence reduced pregnant women's quality of life. Lower urinary tract symptoms are commonly seen among pregnant women and these symptoms negatively affect the quality of life of pregnant women. Advanced age, smoking and multiparity were risk factors associated with urinary incontinence and LUTS. Obstetricians should be on the lookout for individual urological problems in pregnancy. Resolving any urological issues and cessation of smoking for the affected individuals will help alleviate the problem. © 2014 Wiley Publishing Asia Pty Ltd.

Towards the understanding of the molecular weight dependence of essential work of fracture in semi-crystalline polymers: A study on poly(ε-caprolactone

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F. Tuba

2014-11-01

Full Text Available The plane-stress ductile fracture of poly(#-caprolactone (PCL has been investigated as a function of molecular weight and related crystalline structure. Because of the interacting effects in semi-crystalline polymers a separate study of a given structural parameter is rather challenging. Nevertheless, this polymer seems to be a good model material to study the effect of molecular weight on the essential work of fracture, as the interactions between the separate parameters, at room temperature, are negligible. The molecular characteristics of PCL were determined by size exclusion chromatography. To confirm the entangled molecular structure of studied polymers rheological measurements were performed. The crystalline morphology has been characterized by differential scanning calorimetry and wide angle X-ray diffraction. Quasi-static tensile tests and essential work of fracture tests were performed to study the mechanical behavior. Based on the experimental observations an empirical model has been proposed to outline the molecular weight and crystallinity dependence of the essential work of fracture in this semi-crystalline polymer.

MR imaging of pelvic floor in stress urinary incontinence=20

Energy Technology Data Exchange (ETDEWEB)

Lee, Young Rae; Park, Heung Jae; Kook, Shin Ho; Chung, Eun Chul [Kangbuk Samsung Hospital, College of Medicine, Sungkyunkwan University, Seoul (Korea, Republic of)

2000-04-01

To demonstrate the anatomy of the female pelvic floor and to determine the anatomic differences between normal controls and women with stress urinary incontinence, using MRI. Five healthy, young, nulliparous women and 12 with stress urinary incontinence underwent MR imaging. We obtained FSE T2-weighted axial images, 3mm thick, of the region extending from the urethroversical junction to the perineal membrane. The following parameters were determined : angle, asymmetry and signal intensity of the levator ani muscles, the distance between the urethra and symphysis, and the presence, shape and angulation of urethropelvic ligament. In contrast to normal controls, frequent findings in women with stress incontinence were as follows : increased angle (43%), asymmetry (43%) and higher signal intensity (67%) of the levator ani muscles; increased distance between the urethra and symphysis; loss (43%), discontinuity (60%) and dorsal angulation (43%) of the urethropelvic ligament. In women with stress urinary incontinence, MRI clearly demonstrates the anatomy of the female pelvic floor, changes in the levator ani muscles, the distance between the urethra and symphysis, and the urethropelvic ligament. The modality can therefore be used to evaluate the anatomical changes occurring in cases of stress urinary incontinence. (author)

Clinically mild encephalitis/encephalopathy with a reversible splenial lesion associated with febrile urinary tract infection.

Science.gov (United States)

Okamoto, Takayuki; Sato, Yasuyuki; Yamazaki, Takeshi; Hayashi, Asako

2014-04-01

Common pathogens of clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) are viruses, such as influenza virus. However, bacteria are rare pathogens for MERS. We report the first patient with MERS associated with febrile urinary tract infection. A 16-year-old lupus patient was admitted to our hospital. She had fever, headache, vomiting, and right back pain. Urinary analysis showed leukocyturia, and urinary culture identified Klebsiella pneumoniae. Cerebrospinal fluid examination and brain single-photon emission computed tomography showed no abnormalities. Therefore, she was diagnosed with febrile urinary tract infection. For further examinations, 99mTc-dimercaptosuccinic acid renal scintigraphy showed right cortical defects, and a voiding cystourethrogram demonstrated right vesicoureteral reflux (grade II). Therefore, she was diagnosed with right pyelonephritis. Although treatment with antibiotics administered intravenously improved the fever, laboratory findings, and right back pain, she had prolonged headaches, nausea, and vomiting. T2-weighted, diffusion-weighted, and fluid attenuated inversion recovery images in brain magnetic resonance imaging showed high intensity lesions in the splenium of the corpus callosum, which completely disappeared 1 week later. These results were compatible with MERS. To the best of our knowledge, our patient is the first patient who showed clinical features of MERS associated with febrile urinary tract infection. In patients with pyelonephritis and an atypical clinical course, such as prolonged headache, nausea, vomiting, and neurological disorders, the possibility of MERS should be considered.

Extension induced phase separation and crystallization in semidilute solutions of ultra high molecular weight polyethylene

DEFF Research Database (Denmark)

Wingstrand, Sara Lindeblad; Imperiali, Luna; Stepanyan, Roman

2018-01-01

Abstract We investigate the influence of controlled uniaxial extension on various flow induced phenomena in semidilute solutions of ultra high molecular weight polyethylene (UHMwPE). Concentrations range from 9 w% to 29 w% and the choice of solvent is paraffin oil (PO). The start-up extensional b...

Coalescence in PLA-PBAT blends under shear flow: Effects of blend preparation and PLA molecular weight

Energy Technology Data Exchange (ETDEWEB)

Nofar, M. [Center for High Performance Polymer and Composite Systems (CREPEC), Chemical Engineering Department, Polytechnique Montreal, Montreal, Quebec H3T 1J4, Canada and CREPEC, Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 2B2 (Canada); Heuzey, M. C.; Carreau, P. J., E-mail: pierre.carreau@polymtl.ca [Center for High Performance Polymer and Composite Systems (CREPEC), Chemical Engineering Department, Polytechnique Montreal, Montreal, Quebec H3T 1J4 (Canada); Kamal, M. R. [CREPEC, Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 2B2 (Canada); Randall, J. [NatureWorks LLC, 15305 Minnetonka Boulevard, Minnetonka, Minnesota 55345 (United States)

2016-07-15

Blends containing 75 wt. % of an amorphous polylactide (PLA) with two different molecular weights and 25 wt. % of a poly[(butylene adipate)-co-terephthalate] (PBAT) were prepared using either a Brabender batch mixer or a twin-screw extruder. These compounds were selected because blending PLA with PBAT can overcome various drawbacks of PLA such as its brittleness and processability limitations. In this study, we investigated the effects of varying the molecular weight of the PLA matrix and of two different mixing processes on the blend morphology and, further, on droplet coalescence during shearing. The rheological properties of these blends were investigated and the interfacial properties were analyzed using the Palierne emulsion model. Droplet coalescence was investigated by applying shear flows of 0.05 and 0.20 s{sup −1} at a fixed strain of 60. Subsequently, small amplitude oscillatory shear tests were conducted to investigate changes in the viscoelastic properties. The morphology of the blends was also examined using scanning electron microscope (SEM) micrographs. It was observed that the PBAT droplets were much smaller when twin-screw extrusion was used for the blend preparation. Shearing at 0.05 s{sup −1} induced significant droplet coalescence in all blends, but coalescence and changes in the viscoelastic properties were much more pronounced for the PLA-PBAT blend based on a lower molecular weight PLA. The viscoelastic responses were also somehow affected by the thermal degradation of the PLA matrix during the experiments.

Coalescence in PLA-PBAT blends under shear flow: Effects of blend preparation and PLA molecular weight

International Nuclear Information System (INIS)

Nofar, M.; Heuzey, M. C.; Carreau, P. J.; Kamal, M. R.; Randall, J.

2016-01-01

Blends containing 75 wt. % of an amorphous polylactide (PLA) with two different molecular weights and 25 wt. % of a poly[(butylene adipate)-co-terephthalate] (PBAT) were prepared using either a Brabender batch mixer or a twin-screw extruder. These compounds were selected because blending PLA with PBAT can overcome various drawbacks of PLA such as its brittleness and processability limitations. In this study, we investigated the effects of varying the molecular weight of the PLA matrix and of two different mixing processes on the blend morphology and, further, on droplet coalescence during shearing. The rheological properties of these blends were investigated and the interfacial properties were analyzed using the Palierne emulsion model. Droplet coalescence was investigated by applying shear flows of 0.05 and 0.20 s"−"1 at a fixed strain of 60. Subsequently, small amplitude oscillatory shear tests were conducted to investigate changes in the viscoelastic properties. The morphology of the blends was also examined using scanning electron microscope (SEM) micrographs. It was observed that the PBAT droplets were much smaller when twin-screw extrusion was used for the blend preparation. Shearing at 0.05 s"−"1 induced significant droplet coalescence in all blends, but coalescence and changes in the viscoelastic properties were much more pronounced for the PLA-PBAT blend based on a lower molecular weight PLA. The viscoelastic responses were also somehow affected by the thermal degradation of the PLA matrix during the experiments.

A clinical and molecular review of inverted papilloma of the urinary tract

DEFF Research Database (Denmark)

Jørgensen, Peter Hjorth; Vainer, Ben; Hermann, Gregers Gautier

2015-01-01

Inverted papilloma (IP) of the urinary tract is classified by the World Health Organisation as a non-invasive urothelial tumour with normal to minimal cytological atypia of the neoplastic cells. During the 1980s, it came under suspicion of having a premalignant or malignant potential and of being...

Effect of molecular weight and testing rate on adhesion property of pressure-sensitive adhesives prepared from epoxidized natural rubber

International Nuclear Information System (INIS)

Khan, Imran; Poh, B.T.

2011-01-01

Research highlights: → Elucidation of adhesion property of epoxidized natural rubber (ENR 25). → Correlation of peel and shear strength with molecular weight and rate of testing. → Confirmation of miscibility of tackifier and ENR 25 by DSC and FTIR study. → Applicability of Fox equation in ENR 25/coumarone-indene resin system. -- Abstract: The dependence of peel strength and shear strength of epoxidized natural rubber (ENR 25)-based pressure-sensitive adhesive on molecular weight and rate of testing was investigated using coumarone-indene as the tackifying resin. Toluene and polyethylene terephthalate (PET) were used as the solvent and substrate respectively throughout the study. A SHEEN hand coater was used to coat the adhesive on the substrate at a coating thickness of 120 μm. All the adhesion properties were determined by a Llyod Adhesion Tester operating at different rates of testing. Result shows that peel strength and shear strength increases up to an optimum molecular weight of 6.5 x 10 4 of ENR 25. For peel strength, the observation is attributed to the combined effects of wettability and mechanical strength of rubber at the optimum molecular weight, whereas for the shear strength, it is ascribed to the increasing amount of adhesive present in the coating layer which enhances the shear resistance of the adhesive. Peel strength and shear strength also increases with increase in rate of testing, an observation which is associated to the viscoeslastic response of the adhesive. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) study confirms the miscibility of tackifier and the ENR 25.

Urinary extracellular vesicles for RNA extraction: optimization of a protocol devoid of prokaryote contamination.

Science.gov (United States)

Tataruch-Weinert, Dorota; Musante, Luca; Kretz, Oliver; Holthofer, Harry

2016-01-01

Urinary extracellular vesicles (UEVs) represent an ideal platform for biomarker discovery. They carry different types of RNA species, and reported profile discrepancies related to the presence/absence of 18s and 28s rRNA remain controversial. Moreover, sufficient urinary RNA yields and respective quality RNA profiles are still to be fully established. UEVs were enriched by hydrostatic filtration dialysis, and RNA content was extracted using 7 different commercially available techniques. RNA quantity was assessed using spectrophotometry and fluorometry, whilst RNA quality was determined by capillary electrophoresis. The presence of prokaryotic transcriptome was stressed when cellular RNA, as a control, was spiked into the UEVs samples before RNA extraction. The presence of bacteria in hydrostatic filtration dialysis above 1,000 kDa molecular weight cut-off and in crude urine was confirmed with growth media plates. The efficiency in removing urinary bacteria was evaluated by differential centrifugation, filtration (0.22 µm filters) and chemical pretreatment (water purification tablet). For volumes of urine >200 ml, the chemical treatment provides ease of handling without affecting vesicle integrity, protein and RNA profiles. This protocol was selected to enrich RNA with 7 methods, and its respective quality and quantity were assessed. The results were given as follows: (a) Fluorometry gave more repeatability and reproducibility than spectrophotometry to assess the RNA yields, (b) UEVs were enriched with small RNA, (c) Ribosomal RNA peaks were not observed for any RNA extraction method used and (d) RNA yield was higher for column-based method designed for urinary exosome, whilst the highest relative microRNA presence was obtained using TRIzol method. Our results show that the presence of bacteria can lead to misidentification in the electrophoresis peaks. Fluorometry is more reliable than spectrophotometry. RNA isolation method must be selected in conjunction with

Urinary extracellular vesicles for RNA extraction: optimization of a protocol devoid of prokaryote contamination

Directory of Open Access Journals (Sweden)

Dorota Tataruch-Weinert

2016-06-01

Full Text Available Background: Urinary extracellular vesicles (UEVs represent an ideal platform for biomarker discovery. They carry different types of RNA species, and reported profile discrepancies related to the presence/absence of 18s and 28s rRNA remain controversial. Moreover, sufficient urinary RNA yields and respective quality RNA profiles are still to be fully established. Methods: UEVs were enriched by hydrostatic filtration dialysis, and RNA content was extracted using 7 different commercially available techniques. RNA quantity was assessed using spectrophotometry and fluorometry, whilst RNA quality was determined by capillary electrophoresis. Results: The presence of prokaryotic transcriptome was stressed when cellular RNA, as a control, was spiked into the UEVs samples before RNA extraction. The presence of bacteria in hydrostatic filtration dialysis above 1,000 kDa molecular weight cut-off and in crude urine was confirmed with growth media plates. The efficiency in removing urinary bacteria was evaluated by differential centrifugation, filtration (0.22 µm filters and chemical pretreatment (water purification tablet. For volumes of urine >200 ml, the chemical treatment provides ease of handling without affecting vesicle integrity, protein and RNA profiles. This protocol was selected to enrich RNA with 7 methods, and its respective quality and quantity were assessed. The results were given as follows: (a Fluorometry gave more repeatability and reproducibility than spectrophotometry to assess the RNA yields, (b UEVs were enriched with small RNA, (c Ribosomal RNA peaks were not observed for any RNA extraction method used and (d RNA yield was higher for column-based method designed for urinary exosome, whilst the highest relative microRNA presence was obtained using TRIzol method. Conclusion: Our results show that the presence of bacteria can lead to misidentification in the electrophoresis peaks. Fluorometry is more reliable than spectrophotometry. RNA

Urinary Exertion Of Calcium By Urinary Stone Disease Patients And ...

African Journals Online (AJOL)

To compare the urinary excretion of calcium by subjects in a known area of high incidence of urinary stone disease, and a known area of low incidence, 12 adult male patients with idiopathic calcigerous urinary stone disease in south-East Nigeria and 55 similar patients from Scotland, United Kingdom were analyzed ...

Use of Brazilian clay in nylon 6 with different molecular weight nanocomposites

International Nuclear Information System (INIS)

Araujo, Edcleide Maria; Paz, Rene Anisio; Melo, Tomas Jeferson Alves; Leite, Amanda Melissa Damiao; Barbosa, Renata; Ito, Edson Noriyuki

2009-01-01

The effect of nylon 6 (Ny6) molecular weight on the development of polymer/layered silicates nanocomposites prepared by the melt intercalation technique was studied in this work. The nylon6/organoclay nanocomposites were prepared in the counter-rotational twin screw extruder. The results of torque rheometry showed that the presence of organoclay in the nylon 6 increased the torque. The results of X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed exfoliated and/or partially exfoliated structures. (author)

Preparation of Low Allergenic Protein Concentrated Natural Rubber Latex Using Suitable Low Molecular Weight Cellulose Derivatives Induced by Gamma Irradiation

International Nuclear Information System (INIS)

Siri-Upathum, Chyagrit; Boonyawat, Jariya

2007-08-01

Full text: Low molecular weight carboxy methyl cellulose (CMC), hydroxyl ethyl cellulose (HEC), hydroxyl propyl cellulose (HPC) and methyl cellulose (MC) prepared by radiation-induced degradation were added into diluted natural concentrated latex prior to centrifuge for a purpose of reducing allergenic rubber protein in the latex. Optimum molecular weight (Mv) of CMC and HEC for such a purpose was found to be 17-18 kDa which decreased allergenic rubber protein (14-94 kDa) to an undetectable amount as determined by SDS PAGE method

Characterization of high molecular weight cadmium species in contaminated vegetable food

Energy Technology Data Exchange (ETDEWEB)

Guenther, K.; Kastenholz, B. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Chemie und Dynamik der Geosphaere 7: Angewandte Physikalische Chemie; Ji, G. [Bonn Univ. (Germany). Lehrstuhl fuer Lebensmittelwissenschaft und Lebensmittelchemie

2000-10-01

Spinach and radish grown from seeds were each contaminated with 4 different amounts of cadmium. After a cell breakdown of the eatable parts and centrifugation of the resulting homogenates all supernatants (cytosols) were separated by gel permeation chromatography (GPC). The size-range of the GPC method used was about 20-8000 kDa for globular proteins. The high molecular weight (HMW-Cd-SP, 150-700 kDa) and the low molecular weight Cd species (LMW-Cd-SP, < 150 kDa) in all plant cytosols eluted at about the same retention volume by GPC. The most important Cd binding form in the cytosols of all plants was found to be HMW-Cd-SP. The Cd elution maxima were detected in the range of about 200 kDa. The Cd determinations were performed with ET-AAS by means of matrix modifier. By incubating chosen cytosols with a proteinase before the GPC it was verified that the HMW-Cd-SP in both vegetables are Cd proteins. The molar proportions protein/Cd were about 2-6 in the respective GPC fractions of the HMW-Cd-SP of the highest contaminated plants. The GPC fractions of the HMW-Cd-SP of spinach and radish were further separated by a preparative, native and continuous polyacrylamide gel electrophoresis (PAGE) method. At pH 8 the species were negatively charged, had only a small UV-absorption at 280 nm and showed a very similar elution behavior in all analyzed cytosols. Therefore, we suppose that the HMW-Cd-SP of these two different vegetable foodstuffs have a very similar chemical structure. (orig.)

Silver Nanoparticles Modification of Ultra High Molecular Weight Polyethylene in Non-Aqueous Medium

OpenAIRE

V. N. Glushko; L. I. Blokhina; E. E. Anisimova; M. V. Bogdanovskaya; V. I. Kozhukhov; T. A. Cherdyntseva

2016-01-01

A series of experiments for obtaining modified with silver nanoparticles ultra-high molecular weight polyethylene (UHMWPE) is done. Optimal precursors are silver trifluoroacetate, silver nitrate and silver methanesulfonate. Three variants of UHMWPE modification is studied: 1) the polyol synthesis, 2) polymer processing silver nanoparticle colloid and 3) reduction of silver salt solution in the UHMWPE polymer matrix. It is found that the last method is optimal. The specific surface of obtained...

Urinary Incontinence

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... with nerve signals involved in bladder control, causing urinary incontinence. Risk factors Factors that increase your risk of developing urinary incontinence include: Gender. Women are more likely to have ...

Urinary incontinence

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Loss of bladder control; Uncontrollable urination; Urination - uncontrollable; Incontinence - urinary ... and take out yourself. Bladder nerve stimulation. Urge incontinence and urinary frequency can sometimes be treated by electrical nerve ...

Separation of both fibrous and globular proteins on the basis of molecular weight using high-performance size exclusion chromatography.

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Barden, J A

1983-11-01

A high-performance size exclusion liquid chromatographic system has been used to separate proteins with different shapes solely on the basis of their molecular weights. After the effects of ionic and hydrophobic interactions with the stationary phase have been overcome, protein elution is normally governed by their effective size in solution. Conditions are described under which proteins, with isoelectric points within the normal operating pH range of the columns, are eluted independent of their Stokes' radii. Even fibrous proteins with axial ratios of 50 elute according to their known molecular weights over the range 2000-2,000,000.

Determination of low molecular weight thiols using monobromobimane fluorescent labeling and high-performance liquid chromatography

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Fahey, Robert C.; Newton, Gerald L.

1988-01-01

Methods are described for the preparation and high-performance liquid chromatography (HPLC) analysis of monobromobimane derivatives of low molecular weight thiols in extracts of biological samples. Typical problems encountered in the development and application of these methods are discussed. Analysis of mung bean extract is used as an example.

High molecular weight hyaluronic acid increases the differentiation potential of the murine chondrocytic ATDC5 cell line.

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Sato, Eiichi; Ando, Takashi; Ichikawa, Jiro; Okita, Genki; Sato, Nobutaka; Wako, Masanori; Ohba, Tetsuro; Ochiai, Satoshi; Hagino, Tetsuo; Jacobson, Richard; Haro, Hirotaka

2014-12-01

Osteoarthritis (OA) is a group of common, chronic, and painful inflammatory joint diseases. One important finding in OA patients is a remarkable decrease in the molecular weight of hyaluronic acid (HA) in the synovial fluid of affected joints. Therapeutic HA is available to patients in most parts of the world as a viscosupplementation product for the treatment of OA. Previous clinical reports show that high molecular weight HA (HMWHA) more effectively relieves pain than low molecular weight HA (LMWHA). However, the mechanism behind this finding remains unclear. In this study, we investigated whether a LMWHA (Low-0.9 MDa) and two types of HMWHA (High-1.9 MDa and 6 MDa) differentially affected chondroregulatory action. We tested this using ATDC5 cell, a murine chondrocytic cell line widely used in culture systems to study chondrogenic differentiation. We found that HMWHA, especially hylan G-F 20 (High-6 MDa), significantly induced aggrecan and proteoglycan accumulation, nodule formation, and mRNA expression of chondrogenic differentiation markers in a time- and dose-dependent manner. In addition, we showed that HMWHA prevented TNF-α induced inhibition of chondrogenic differentiation, with no effect on cell proliferation or viability. These results reveal that HMWHA significantly promotes chondrogenic differentiation of ATDC5 cells in vitro, and suggest that HMWHA plays a significant chondroregulatory role in vivo. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Effect of low molecular weight heparin in combined with Shuxuetong in preventing the post-traumatic deep venous thrombosis

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Li-Mian Xu

2016-05-01

Full Text Available Objective: To observe the effect of low molecular weight heparin in combined with Shuxuetong in preventing the post-traumatic deep venous thrombosis (DVT. Methods: A total of 120 patients with post-traumatic DVT who were admitted in our hospital from February, 2014 to February, 2015 were included in the study and divided into the treatment group and the control group with 60 cases in each group according to different treatment protocols. The patients in the treatment group were given subcutaneous injection of low molecular weight heparin calcium and intravenous drip of Shuxuetong, while the patients in the control group were only given subcutaneous injection of low molecular weight heparin calcium. The changes of swelling degrees and coagulation indicators of the affected limb before and after treatment, and the clinical efficacy in the two groups were compared. Results: The total effective rate in the treatment group was significantly higher than that in the control group. The mean range of the perimeter 15cm above and below the bilateral knee joints after treatment in the treatment group was significantly lower than that in the control group. The shrinking rate of the mean range of the perimeter of the bilateral limbs in the treatment group was significantly higher than that in the control group. The comparison of PT, APTT, FIB, and INR before treatment between the two groups was not statistically significant. PT, APTT, and INR after treatment in the treatment group were significantly higher than those in the control group, while FIB was significantly lower than that in the control group. Conclusions: The low molecular weight heparin in combined with Shuxuetong can effectively prevent the post-traumatic DVT, with no requirement of monitoring of the bleeding tendency and safety.

Effect of molecular weight on radiation chemical degradation yield of chain scission of γ-irradiated chitosan in solid state and in aqueous solution

International Nuclear Information System (INIS)

Tahtat, Djamel; Mahlous, Mohamed; Benamer, Samah; Nacer Khodja, Assia; Larbi Youcef, Souad

2012-01-01

Chitosan A 1 , A 2 and A 3 with molecular weight of 471, 207 and 100 kDa respectively, produced from squid pen chitin was degraded by gamma rays in the solid state and in aqueous solution with various doses in air at ambient temperature. Effect of molecular weight on radiation chemical degradation yield of chain scission and degradation rate constants of γ-irradiated chitosan in solid state and in aqueous solution was investigated. The radiation chemical degradation yield G (s) and degradation rate values were calculated. The molecular weight changes were monitored by capillary viscometry method and the chemical structure changes were followed by UV analysis. The results showed that, the degradation of chitosan was faster in solution, than in solid state. The values of G (s) in solid state and in aqueous solution were respectively 1.1×10 −8 mol/J and 0.074×10 −7 mol/J for A 1 , 4.42×10 −8 mol/J and 0.28×10 −7 mol/J for A 2 and 6.08×10 −8 mol/J and 0.38×10 −7 mol/J for A 3 . Degradation rate constants values ranged from 0.41×10 −5 to 2.1×10 −5 kGy −1 in solid state, whereas in solution they ranged from 13×10 −5 to 68×10 −5 kGy −1 . The chitosan A 3 was more sensitive to radiolysis than A 1 and A 2 . The chain scission yield, G (s) and degradation rate constants seems to be greatly influenced by the initial molecular weight of the chitosan. Structural changes in irradiated chitosan are revealed by the apparition of absorption peaks at 261 and 295 nm, which could be attributed to the formation of carbonyl groups. In both conditions the peak intensity was higher in chitosan A 3 than in A 1 and A 2 , the oxidative products decreased with increasing molecular weight of chitosan. - Highlights: ► We investigated the effects of MW on G (s) value of γ-irradiated chitosan in solid and aqueous state. ► Chitosan with low molecular weight was more sensitive to radiolysis than high molecular weight. ► G (s) value and degradation rate

Diabetes, glycemic control, and urinary incontinence in women

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Wang, Rui; Lefevre, Roger; Hacker, Michele R.; Golen, Toni H.

2015-01-01

OBJECTIVES To estimate the association between urinary incontinence and glycemic control in women ages 20 to 85. METHODS We included 7,270 women from the 2005–2010 National Health and Nutrition Examination Survey, stratified into three groups of glycemic control defined by hemoglobin A1c (HbA1c): i) those below the diagnostic threshold (HbA1c8.5%) to allow for a different relationship between glycemic control and urinary incontinence within each group. The primary outcomes were the presence of any, only stress, only urgency, and mixed urinary incontinence. We calculated adjusted risk ratios using Poisson regressions with robust variance estimates. RESULTS The survey-weighted prevalence was 52.9% for any, 27.2% for only stress, 9.9% for only urgency, and 15.8% for mixed urinary incontinence. Among women with relatively controlled diabetes, each one-unit increase in HbA1c was associated with a 13% (95% CI: 1.03–1.25) increase for any urinary incontinence and a 34% (95% CI 1.06–1.69) increase in risk for only stress incontinence but was not significantly associated with only urgency and mixed incontinence. Other risk factors included body mass index, hormone replacement therapy, smoking, and physical activity. CONCLUSIONS Worsening glycemic control is associated with an increased risk for stress incontinence for women with relatively controlled diabetes. For those either below the diagnostic threshold or with poorly controlled diabetes, the risk may be driven by other factors. Further prospective investigation of HbA1c as a modifiable risk factor may motivate measures to improve continence in women with diabetes. PMID:26313496

[Extracellular hydration status and residual urinary sodium excretion in chronic hemodialysis patients: a cross-sectional multicenter study].

Science.gov (United States)

Crochette, Romain; Lobbedez, Thierry; Hanoy, Mélanie; Le Roy, Frank; Potier, Jacky; Besselièvre, Thibault; Cardineau, Éric; Landru, Isabelle; Ficheux, Maxence; Ryckelynck, Jean-Philippe; Henri, Patrick

2014-04-01

In dialysis patients, a misevaluation of dry weight may lead to an increased morbidity and mortality. The aim of this cross-sectional multicenter study was to evaluate the association between residual urinary sodium excretion and extracellular volume status in chronically treated hemodialysis patients. Dry weight was determined clinically and by whole-body bioimpedance spectroscopy (Body Composition Monitor, Fresenius Medical Care) prior to a mid-week session in 40 chronic hemodialysis patients with significant residual diuresis (more than 250 mL per day) and receiving treatment in four dialysis centers. Regarding their hydration status assessed by the Body Composition Monitor and in comparison to a healthy reference population, patients were assigned to 1 of the 3 categories: overhydrated, normohydrated and dehydrated. Urine output, urinary sodium excretion and residual renal function were measured for all patients within 30 days before dry weight assessment. The median post-HD session FO was of-0.40 L (IQR: from-1.95 to+0.90) and the median residual urinary sodium excretion was of 64 mmol/L (IQR: 46-79). Among these patients, 16 were normohydated, 16 were dehydrated and 8 were overhydrated. There was a linear relationship between the hydration status after HD session and the urinary sodium excretion (estimate: 5.6±1.5; phydration status evaluated by whole-body bioimpedance spectroscopy. Copyright © 2013 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

Single intra-articular injection of high molecular weight hyaluronic acid for hip osteoarthritis.

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Rivera, Fabrizio

2016-03-01

Intra-articular (IA) injection of hyaluronic acid (HA) into the hip joint appears to be safe and well tolerated but only a small number of randomized clinical trials in humans has been published. The objective of this prospective study was to evaluate the efficacy and safety of a single IA injection of high-molecular-weight (2800 kDa) HA (Coxarthrum) for hip osteoarthritis. All patients received a single IA administration of 2.5 % sodium hyaluronate (75 mg/3 mL) of high molecular weight. Fluoroscopy requires an iodized contrast medium (iopamidol, 1 ml) which highlights the capsule before administering HA. Patients were evaluated before IA injection (T0), after 3 months, after 6 months and after 1 year from injection. Results were evaluated by the Brief Pain Inventory (BPI II), Harris Hip Score and a visual analog scale of pain (pain VAS). All treated patients were considered for statistical analysis. Two hundred seven patients were included at T0. The mean age was 67 years (range 46-81). Regarding BPI severity score, changes in pain between T0 and the three following visits were statistically highly significant (p injection of Coxarthrum is effective from the third month and that the results are stable or continue to improve up to 1 year. IV.

Topochemical approach to efficiently produce main-chain poly(bile acid)s with high molecular weights.

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Li, Weina; Li, Xuesong; Zhu, Wei; Li, Changxu; Xu, Dan; Ju, Yong; Li, Guangtao

2011-07-21

Based on a topochemical approach, a strategy for efficiently producing main-chain poly(bile acid)s in the solid state was developed. This strategy allows for facile and scalable synthesis of main-chain poly(bile acid)s not only with high molecular weights, but also with quantitative conversions and yields.

Tumor microvascular changes in antiangiogenic treatment : Assessment by magnetic resonance contrast media of different molecular weights

NARCIS (Netherlands)

Turetschek, K; Preda, A; Novikov, [No Value; Brasch, RC; Weinmann, HJ; Wunderbaldinger, P; Roberts, TPL

Purpose: To test magnetic resonance (MR) contrast media of different molecular weights (MWs) for their potential to characterize noninvasively microvascular changes in an experimental tumor treatment model. Materials and Methods: MD-MBA-435, a poorly differentiated human breast cancer cell line, was

Use of low molecular weight Heparin for Hemodialysis: A short term study

International Nuclear Information System (INIS)

Al-Arrayed, S.; Seshadri, R.

2002-01-01

Although unfractionated heparin (UFH) is the anticoagulant commonly usedfor Hemodialysis (HD), low molecular weight heparin (LMWH) has been found tobe equally efficacious. The aim of this study was to explore the safety andefficacy of a single bolus dose of the LMWH, enoxaparin. Thirty-eightpatients on maintenance HD were randomly divided into two equal groups. Themean age and body-weight of the two were comparable. While one group received1 mg/kg body-weight (the manufacturer's recommended dose) of enoxaparin forthree dialysis sessions of three-hour duration each, the either groupreceived a fixed dose of 40 mg for the same number of dialysis. For the nextthree dialysis sessions, these doses were exchanged between the groups. Inall, total of 228 HD sessions were monitored for clotting of bloodlines/dialyzers and bleeding from vascular access and other sites. The rateof complications was compared with the historical data while UFH was beingused for the same patients. In general, enoxapirin was associated with fewerepisodes of bleeding and clotting. Our study confirms that LMWH is ofcomparable efficacy to UFH and probably a lesser than recommended dose isadequate for three-hour HD session. (author)

Amino Acid Composition, Molecular Weight Distribution and Gel Electrophoresis of Walnut (Juglans regia L. Proteins and Protein Fractionations

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Xiaoying Mao

2014-01-01

Full Text Available As a by-product of oil production, walnut proteins are considered as an additional source of plant protein for human food. To make full use of the protein resource, a comprehensive understanding of composition and characteristics of walnut proteins are required. Walnut proteins have been fractionated and characterized in this study. Amino acid composition, molecular weight distribution and gel electrophoresis of walnut proteins and protein fractionations were analyzed. The proteins were sequentially separated into four fractions according to their solubility. Glutelin was the main component of the protein extract. The content of glutelin, albumin, globulin and prolamin was about 72.06%, 7.54%, 15.67% and 4.73% respectively. Glutelin, albumin and globulin have a balanced content of essential amino acids, except for methionine, with respect to the FAO pattern recommended for adults. SDS-PAGE patterns of albumin, globulin and glutelin showed several polypeptides with molecular weights 14.4 to 66.2 kDa. The pattern of walnut proteins in two-dimension electrophoresis (2-DE showed that the isoelectric point was mainly in the range of 4.8–6.8. The results of size exclusion chromatogram indicated molecular weight of the major components of walnut proteins were between 3.54 and 81.76 kDa.

Deproteinization assessment using isotopically enriched compounds to trace the coprecipitation of low-molecular-weight selenium species with proteins.

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Godin, Simon; Bouzas-Ramos, Diego; Fontagné-Dicharry, Stéphanie; Bouyssière, Brice; Bueno, Maïté

2017-08-01

Studies have shown that information related to the presence of low-molecular-weight metabolites is frequently lost after deproteinization of complex matrices, such as blood and plasma, during sample preparation. Therefore, the effect of several deproteinization reagents on low-molecular-weight selenium species has been compared by species-specific isotope labeling. Two isotopically enriched selenium tracers were used to mimic models of small inorganic anionic ( 77 Se-selenite) and organic zwitterionic ( 76 Se-selenomethionine) species. The results presented here show that the use of a methanol-acetonitrile-acetone (1:1:1 v/v/v) mixture provided approximately two times less tracer loss from plasma samples in comparison with the classic procedure using acetonitrile, which may not be optimal as it leads to important losses of low-molecular-weight selenium species. In addition, the possible interactions between selenium tracers and proteins were investigated, revealing that both coprecipitation phenomena and association with proteins were potentially responsible for selenite tracer losses during protein precipitation in blood samples. However, coprecipitation phenomena were found to be fully responsible for losses of both tracers observed in plasma samples and of the selenomethionine tracer in blood samples. This successfully applied strategy is anticipated to be useful for more extensive future studies in selenometabolomics. Copyright © 2017 Elsevier Inc. All rights reserved.

Female urinary incontinence and sexuality

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Renato Lains Mota

Full Text Available ABSTRACT Urinary incontinence is a common problem among women and it is estimated that between 15 and 55% of them complain of lower urinary symptoms. The most prevalent form of urinary incontinence is associated with stress, followed by mixed urinary incontinence and urge urinary incontinence. It is a symptom with several effects on quality of life of women mainly in their social, familiar and sexual domains. Female reproductive and urinary systems share anatomical structures, which promotes that urinary problems interfere with sexual function in females. This article is a review of both the concepts of female urinary incontinence and its impact on global and sexual quality of life. Nowadays, it is assumed that urinary incontinence, especially urge urinary incontinence, promotes anxiety and several self-esteem damages in women. The odour and the fear of incontinence during sexual intercourse affect female sexual function and this is related with the unpredictability and the chronicity of incontinence, namely urge urinary incontinence. Female urinary incontinence management involves conservative (pelvic floor muscle training, surgical and pharmacological treatment. Both conservative and surgical treatments have been studied about its benefit in urinary incontinence and also the impact among female sexual function. Unfortunately, there are sparse articles that evaluate the benefits of female sexual function with drug management of incontinence.

Female urinary incontinence and sexuality

Science.gov (United States)

Mota, Renato Lains

2017-01-01

ABSTRACT Urinary incontinence is a common problem among women and it is estimated that between 15 and 55% of them complain of lower urinary symptoms. The most prevalent form of urinary incontinence is associated with stress, followed by mixed urinary incontinence and urge urinary incontinence. It is a symptom with several effects on quality of life of women mainly in their social, familiar and sexual domains. Female reproductive and urinary systems share anatomical structures, which promotes that urinary problems interfere with sexual function in females. This article is a review of both the concepts of female urinary incontinence and its impact on global and sexual quality of life. Nowadays, it is assumed that urinary incontinence, especially urge urinary incontinence, promotes anxiety and several self-esteem damages in women. The odour and the fear of incontinence during sexual intercourse affect female sexual function and this is related with the unpredictability and the chronicity of incontinence, namely urge urinary incontinence. Female urinary incontinence management involves conservative (pelvic floor muscle training), surgical and pharmacological treatment. Both conservative and surgical treatments have been studied about its benefit in urinary incontinence and also the impact among female sexual function. Unfortunately, there are sparse articles that evaluate the benefits of female sexual function with drug management of incontinence. PMID:28124522

Low molecular weight thiols and thioredoxins are important players in Hg(II) resistance in Thermus thermophilus HB27.

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Norambuena, J; Wang, Y; Hanson, T; Boyd, J M; Barkay, T

2017-11-17

Mercury (Hg), one of the most toxic and widely distributed heavy metals, has a high affinity for thiol groups. Thiol groups reduce and sequester Hg. Therefore, low molecular weight and protein thiols may be important cell components used in Hg resistance. To date, the role of low molecular weight thiols in Hg-detoxification remains understudied. The mercury resistance ( mer ) operon of Thermus thermophilus suggests an evolutionary link between Hg(II) resistance and low molecular weight thiol metabolism. This mer operon encodes for an enzyme involved in methionine biosynthesis, Oah. Challenge with Hg(II) resulted in increased expression of genes involved in the biosynthesis of multiple low molecular weight thiols (cysteine, homocysteine, and bacillithiol), as well as the thioredoxin system. Phenotypic analysis of gene replacement mutants indicated that Oah contributes to Hg resistance under sulfur limiting conditions, and strains lacking bacillithiol and/or thioredoxins are more sensitive to Hg(II) than the wild type. Growth in presence of either a thiol oxidizing agent or a thiol alkylating agent increased sensitivity to Hg(II). Furthermore, exposure to 3 μM Hg(II) consumed all intracellular reduced bacillithiol and cysteine. Database searches indicate that oah2 is present in all Thermus spp. mer operons. The presence of a thiol related gene was also detected in some alphaprotobacterial mer operons, in which a glutathione reductase gene was present, supporting the role of thiols in Hg(II) detoxification. These results have led to a working model in which LMW thiols act as Hg(II) buffering agents while Hg is reduced by MerA. Importance The survival of microorganisms in presence of toxic metals is central to life's sustainability. The affinity of thiol groups to toxic heavy metals drives microbe-metal interactions and modulate metal toxicity. Mercury detoxification ( mer ) genes likely originated early in microbial evolution among geothermal environments. Little is

ADME-Tox profiling of some low molecular weight water soluble chitosan derivatives

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Adriana Isvoran

2017-09-01

Full Text Available Within this study we use a few computational tools for predicting absorption, distribution, metabolism, excretion and toxicity (ADME-Tox, pharmacokinetics profiles, toxic/adverse effects, carcinogenicity, cardiotoxicity and endocrine disruption of some of low molecular weight water soluble derivatives of chitosan that are used in wound healing. Investigated compounds do not possess drug-like properties, their pharmacokinetics profiles reveal poor gastrointestinal absorption and low skin penetration. Chitosan derivatives cannot pass the blood-brain barrier and they are not able to inhibit the enzymes of the cytochrome P450 that are involved in the metabolism of xenobiotics. They do not reflect carcinogenicity and cardiotoxicity and reveal only a low probability to be endocrine disruptors. The main side effects in humans of the investigated compounds are: weight loss, acidosis, gastrointestinal toxicity, respiratory failure. This information is especially important for professional exposure and accidental contamination with these compounds.

Molecular Characterization of Urothelial Carcinoma of the Bladder and Upper Urinary Tract

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Ji Yun Lee

2018-02-01

Full Text Available PURPOSE: A better understanding of the molecular basis of urothelial carcinoma (UC is needed to refine the clinical decision-making process. METHODS AND MATERIALS: We performed next-generation sequencing to investigate the mutational and transcriptional profiles of commonly mutated genes in UC using Ampliseq v2. Copy number variations (CNVs were detected with nCounter assay. Genetic alterations between upper tract UC (UTUC and urinary bladder UC (UBUC were compared. RESULTS: Tumor samples from 31 UTUC and 61 UBUC patients were included in analysis. The two groups showed similar clinicopathologic features including tumor grade and stage. Median survival was longer in UTUC than UBUC patients, though this was statistically nonsignificant (59 vs 41 months, P = .137. In total, we found 982 genetic alterations from 92 samples: single nucleotide variants were the most common type of somatic mutation (479/508, 94.3%. Frequently detected somatic mutations included TP53 (68.5%, KDR (41.3%, and PIK3CA (17.4%. Notably, RB1 mutations were the only mutations significantly different between the UBUC and UTUC groups (19.7% vs. 0%, P = .020. The most common types of CNVs included amplifications (56/62, 90.3%: 17.7% of patients identified amplifications in NOTCH1. We also identified five translocations in the entire study population, including one case with FGFR3-TACC3 (Chr4 fusion. CONCLUSION: Within a small study population, we identified similar genetic alterations in both UTUC and UBUC patients, indicating a basis for similar management strategies.

Tailoring of the Nanotexture of Mesoporous Silica Films and their Functionalized Derivatives for Selectively Harvesting Low Molecular Weight Protein

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Hu, Ye; Bouamrani, Ali; Tasciotti, Ennio; Li, Li; Liu, Xuewu; Ferrari, Mauro

2010-01-01

We present a fast, efficient and reliable system based on mesoporous silica chips to specifically fractionate and enrich the low molecular weight proteome. Mesoporous silica thin films with tunable features at the nanoscale were fabricated using the triblock copolymer template pathway. Using different templates and concentrations in the precursor solution, various pore size distributions, pore structures and connectivity were obtained and applied for selective recovery of low mass proteins. In combination with mass spectrometry and statistic analysis, we demonstrated the correlation between the nanophase characteristics of the mesoporous silica thin films and the specificity and efficacy of low mass proteome harvesting. In addition, to overcome the limitations of the pre-functionalization method in polymer selection, plasma ashing was used for the first time for the treatment of the mesoporous silica surface prior to chemical modification. Surface charge modifications by different functional groups resulted in a selective capture of the low molecular weight proteins from serum sample. In conclusion our study demonstrates that the ability to tune the physico-chemical properties of mesoporous silica surfaces, for a selective enrichment of the low molecular weight proteome from complex biological fluids, has the potential to promote proteomic biomarker discovery. PMID:20014864

[Postpartum urinary and fecal incontinence in gemelar pregnancy according to route and mode of delivery].

Science.gov (United States)

Cuerva González, Marcos Javier; López Carpintero, Nayara; de la Calle Fernández, Miranda María; Usandizaga, Ramón; González, Antonio

2011-09-01

The incidence of multiple pregnancies increased in the last two decades. Several studies seeking the incidence of pelvic floor pathology, particularly urinary incontinence and its risk factors, conclude that a previous cesarean and vaginal delivery even more, carry an increased risk for developing urinary and fecal incontinence, compared with patients nulligravida. To determine the different risk factors for urinary incontinence after a twin pregnancy. 331 women from 20 to 50 years of age without symptoms prior to pregnancy were interviewed, attending antenatal care of twin pregnancy in the Hospital La Paz, Madrid. The interview included the ICIQ-SF (International Consultation on Incontinence Questionnaire-Short Form). We recorded maternal age, gestational age, parity, episiotomy, weights of both newborns, the need for urinary protectors and fecal or gas incontinence. The prevalence of urinary incontinence postpartum according ICIQ-SF >0 was 23%; 20.4% in the caesarean group, 25.3% in the eutocic delivery group and 35.5% in the instrumental delivery group (p = 0.033). The prevalence of moderate to severe incontinence (ICIQ-SF >6) was 14.8%; 12.3% in caesarean group, 14.5% in the eutocic delivery group and 32.3% in the instrumental delivery group (p = 0.005). The prevalence of fecal incontinence was 3.4%; 4.8% in eutocic delivery group, 1.9% in the caesarean group and 9.7% in the instrumental delivery group (p = 0.058). The risk of urinary incontinence after a twin pregnancy was higher among patients who had an instrumental delivery when compared with patients with eutocic delivery or cesarean section. The total fetal weight and maternal age did not appear as risk factors in our study. Any woman who had an instrumental delivery for twins should be followed up by a pelvic floor specialist.

Comprehensive Analysis of Low-Molecular-Weight Human Plasma Proteome Using Top-Down Mass Spectrometry.

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Cheon, Dong Huey; Nam, Eun Ji; Park, Kyu Hyung; Woo, Se Joon; Lee, Hye Jin; Kim, Hee Cheol; Yang, Eun Gyeong; Lee, Cheolju; Lee, Ji Eun

2016-01-04

While human plasma serves as a great source for disease diagnosis, low-molecular-weight (LMW) proteome (mass spectrometry to analyze the LMW proteoforms present in four types of human plasma samples pooled from three healthy controls (HCs) without immunoaffinity depletion and with depletion of the top two, six, and seven high-abundance proteins. The LMW proteoforms were first fractionated based on molecular weight using gel-eluted liquid fraction entrapment electrophoresis (GELFrEE). Then, the GELFrEE fractions containing up to 30 kDa were subjected to nanocapillary-LC-MS/MS, and the high-resolution MS and MS/MS data were processed using ProSightPC 3.0. As a result, a total of 442 LMW proteins and cleaved products, including those with post-translational modifications and single amino acid variations, were identified. From additional comparative analysis of plasma samples without immunoaffinity depletion between HCs and colorectal cancer (CRC) patients via top-down approach, tens of LMW proteoforms, including platelet factor 4, were found to show >1.5-fold changes between the plasma samples of HCs and CRC patients, and six of the LMW proteins were verified by Western blot analysis.

Dietary factors associated with plasma high molecular weight and total adiponectin levels in apparently healthy women

NARCIS (Netherlands)

Yannakoulia, Mary; Yiannakouris, Nikos; Melistas, Labros; Fappa, Evaggelia; Vidra, Nikoletta; Kontogianni, Meropi D; Mantzoros, Christos S

2008-01-01

OBJECTIVE: Our aim was to investigate associations between dietary factors and high molecular weight (HMW) as well as total adiponectin in a sample of apparently healthy adult Mediterranean women. DESIGN AND METHODS: Two hundred and twenty women were enrolled in this study. Anthropometric and body

Urinary incontinence - injectable implant

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... repair; ISD repair; Injectable bulking agents for stress urinary incontinence ... and disorders: physiology of micturition, voiding dysfunction, urinary incontinence, urinary tract infections, and painful bladder syndrome. In: Lobo ...

The Efficiency and Safety of Tension-Free Vaginal Tape (TVT) Abbrevo Procedure Versus TVT Exact in the Normal Weight and Overweight Patients Affected by Stress Urinary Incontinence.

Science.gov (United States)

Sun, Yi; Luo, Deyi; Yang, Lu; Wei, Xin; Tang, Cai; Chen, Mei; Shen, Hong; Wei, Qiang

2017-12-01

To compare the efficacy between 2 different slings in normal weight and overweight women. Of 426 women, 220 (119 normal weight and 101 overweight) accepted the tension-free vaginal tape Abbrevo (TVT-A) and 206 (114 normal weight and 92 overweight) accepted the TVT Exact (TVT-E) procedure. Data collected contained the subjective efficiency, objective efficiency International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF), Incontinence Quality of Life Questionnaire (I-QOL), Pelvic Floor Impact Questionnaire-Short Form (PFIQ-7), Urogenital Distress Inventory-Short Form (UDI-6), and Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire-Short Form (PISQ)-12 at 36 months after surgery. In the normal weight patients, the subjectively and objectively cured rates were all high in both TVT-A and TVE-E (94.12% and 95.61% in objective result; 92.44% and 94.74% in subjective result). In addition, the score of I-QOL, PFIQ-7, and UDI-6 have significantly changed (P TVT-E than TVT-A. Moreover, the score of I-QOL, PFIQ-7, and UDI-6 of overweight women have significantly changed only in the TVT-E (P TVT-A and TVT-E, respectively). The TVT-E might be a better choice for the overweight patient than TVT-A. Copyright © 2017 Elsevier Inc. All rights reserved.

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

Institute of Scientific and Technical Information of China (English)

Jiang-qing Pan

2001-01-01

Over 2 × l08 tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The sructure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.``

Pathophysiology of nocturnal lower urinary tract symptoms in older patients with urinary incontinence.

Science.gov (United States)

Denys, Marie-Astrid; Decalf, Veerle; Kumps, Candy; Petrovic, Mirko; Goessaert, An-Sofie; Everaert, Karel

2017-11-01

To explore the mismatch between functional bladder capacity and nocturnal urine production, and to study the pathophysiology of an increased nocturnal urine production in older patients with urinary incontinence. The present prospective observational study included adults aged ≥65 years with urinary incontinence. Participants completed questionnaires, frequency volume charts and renal function profiles. The nocturnal lower urinary tract symptom index was defined as nocturnal urine output/maximum voided volume; the nocturnal polyuria index as nocturnal/24 h urine output. The median age (n = 95) was 74 years (69-79), 87% were women and 73% had nocturnal lower urinary tract symptoms (nocturnal urinary incontinence or nocturia ≥2). Participants with nocturnal lower urinary tract symptoms had a significantly higher nocturnal urine output (809 mL vs 650 mL; P = 0.001) and no significant difference in maximum voided volume (350 mL vs 437 mL; P = 0.079) compared with participants without nocturnal lower urinary tract symptoms. Participants (nocturnal polyuria index >33% [n = 56], nocturnal polyuria index >40% [n = 42], nocturnal lower urinary tract symptom index >1.87 [n = 51]) showed higher night-time diuresis rates, free water and sodium clearance compared with during the daytime. Controls (nocturnal polyuria index ≤33% [n = 26], nocturnal polyuria index ≤40% [n = 40], nocturnal lower urinary tract symptom index ≤1.87 [n = 44]) had no circadian rhythm in their diuresis rate or sodium clearance, but more nocturnal free water clearance compared with during the daytime. The majority of older adults with urinary incontinence present nocturnal lower urinary tract symptoms. An increased nocturnal sodium diuresis seems to be the only mechanism differentiating patients with nocturnal lower urinary tract symptoms from controls. © 2017 The Japanese Urological Association.

Degradation and mineralization of high-molecular-weight polycyclic aromatic hydrocarbons by defined fungal-bacterial cocultures

International Nuclear Information System (INIS)

Boonchan, S.; Britz, M.L.; Stanley, G.A.

2000-01-01

This study investigated the biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) in liquid media and soil by bacteria (Stenotrophomonas maltophilia VUN 10,010 and bacterial consortium VUN 10,009) and a fungus (Penicillium janthinellum VUO 10,201) that were isolated from separate creosote- and manufactured-gas plant-contaminated soils. The bacteria could use pyrene as their sole carbon and energy source in a basal salts medium (BSM) and mineralized significant amounts of benzo[a]pyrene cometabolically when pyrene was also present in BSM. P. janthinellum VUO 10,201 could not utilize any high-molecular-weight PAH as sole carbon and energy source but could partially degrade these if cultured in a nutrient broth. Although small amounts of chrysene, benz[a]pyrene, and dibenz[a,h]anthracene were degraded by axenic cultures of these isolates in BSM containing a single PAH, such conditions did not support significant microbial growth or PAH mineralization. However, significant degradation of, and microbial growth on, pyrene, chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene, each as a single PAH in BSM, occurred when P. janthinellum VUO 10,201 and either bacterial consortium VUN 10,009 or S. maltophilia VUN 10,010 were combined in the one culture, i.e., fungal-bacterial cocultures: 25% of the benzo[a]pyrene was mineralized to CO 2 by these cocultures over 49 days, accompanied by transient accumulation and disappearance of intermediates detected by high-pressure liquid chromatography. Inoculation of fungal-bacterial cocultures into PAH-contaminated soil resulted in significantly improved degradation of high-molecular-weight PAHs, benzo[a]pyrene mineralization, and reduction in the mutagenicity of organic soil extracts, compared with the indigenous microbes and soil amended with only axenic inocula

Weight Measurement Chitosan Molecule using GPC-MALLS

International Nuclear Information System (INIS)

Mohd Yusof Hamzah; Norhashidah Talip; Maznah Mahmud

2011-01-01

Research on basic characteristics and application of practical chitosan are need in order to understand their physical and chemical properties of this materials. One of the physico chemical properties that important for every polymers is absolute molecular weights. The important of this aspects has give big impacts on non colligative of the polymers, for example, viscosity, solubility and so on. Absolute weight molecular weights of each polymers can be measured by using GPC-MALLS. This device functioned as molecular size separator and molecular weight measurement by integration of the information such as sample concentration, light scattering index and sample reaction information using laser radiation irradiated from 18 angles.In this scope, we will discuss deeply on absolute weight molecular measurement of chitosan by using GPC-MALLS. (author)

High Performance Shape Memory Polyurethane Synthesized with High Molecular Weight Polyol as the Soft Segment

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Manzoor Ahmad

2012-05-01

Full Text Available Shape memory polyurethanes (SMPUs are typically synthesized using polyols of low molecular weight (MW~2,000 g/mol as it is believed that the high density of cross-links in these low molecular weight polyols are essential for high mechanical strength and good shape memory effect. In this study, polyethylene glycol (PEG-6000 with MW ~6000 g/mol as the soft segment and diisocyanate as the hard segment were used to synthesize SMPUs, and the results were compared with the SMPUs with polycaprolactone PCL-2000. The study revealed that although the PEG-6000-based SMPUs have lower maximum elongations at break (425% and recovery stresses than those of PCL-based SMPUs, they have much better recovery ratios (up to 98% and shape fixity (up to 95%, hence better shape memory effect. Furthermore, PEG-based SMPUs showed a much shorter actuation time of < 10 s for up to 90% shape recovery compared to typical actuation times of tens of seconds to a few minutes for common SMPUs, demonstrated their great potential for applications in microsystems and other engineering components.

Effect of poly(lactide-co-glycolide) molecular weight on the release of dexamethasone sodium phosphate from microparticles.

Science.gov (United States)

Jaraswekin, Saowanee; Prakongpan, Sompol; Bodmeier, Roland

2007-03-01

The objective of this study was to investigate the effect of poly(lactide-co-glycolide) (PLGA) molecular weight (Resomer RG 502H, RG 503H, and RG 504H) on the release behavior of dexamethasone sodium phosphate-loaded microparticles. The microparticles were prepared by three modifications of the solvent evaporation method (O/W-cosolvent, O/W-dispersion, and W/O/W-methods). The encapsulation efficiency of microparticles prepared by the cosolvent- and W/O/W-methods increased from approximately 50% to >90% upon addition of NaCl to the external aqueous phase, while the dispersion method resulted in lower encapsulation efficiencies. The release of dexamethasone sodium phosphate from PLGA microparticles (>50 microm) was biphasic. The initial burst release correlated well with the porosity of the microparticles, both of which increased with increasing polymer molecular weight (RG 504H > 503H > 502H). The burst was also dependent on the method of preparation and was in the order of dispersion method > WOW method > consolvent method. In contrast to the higher molecular weight PLGA microparticles, the release from RG 502H microparticles prepared by cosolvent method was not affected by volume of organic solvent (1.5-3.0 ml) and drug loading (4-13%). An initial burst of approximately 10% followed by a 5-week sustained release phase was obtained. Microparticles with a size <50 microm released in a triphasic manner; an initial burst was followed by a slow release phase and then by a second burst.

Vitamin K antagonists or low-molecular-weight heparin for the long term treatment of symptomatic venous thromboembolism

NARCIS (Netherlands)

van der Heijden, J. F.; Hutten, B. A.; Büller, H. R.; Prins, M. H.

2002-01-01

BACKGROUND: People with venous thromboembolism are generally treated for five days with intravenous unfractionated heparin or subcutaneous low-molecular-weight heparin followed by three months of vitamin K antagonists treatment. Treatment with vitamin K antagonists requires regular laboratory

Pasteurella multocida urinary tract infection with molecular evidence of zoonotic transmission.

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Liu, Wendy; Chemaly, Roy F; Tuohy, Marion J; LaSalvia, Margaret M; Procop, Gary W

2003-02-15

We describe a patient with a urinary tract infection (UTI) caused by Pasteurella multocida. Pulsed-field gel electrophoresis revealed that the clinical isolate recovered from the patient was identical (100% band match) to P. multocida isolates recovered from the patient's cat, but the isolate differed from an isolate recovered from a visiting cat and from a laboratory control strain. The patient also had abnormal urologic anatomy secondary to surgery; this has also been associated with P. multocida UTI.

The role of serum and urinary urea in the evaluation of enteral protein intake in adequate and small-for-gestational-age very low birth weight infants

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Silvana Darcie

Full Text Available CONTEXT AND OBJECTIVE: Very low birth weight (VLBW infants have special nutritional needs. There is a current tendency to individualize their protein needs. The objective of this study was to determine the suitability of serum and urinary urea as indicators for protein intake in adequate-for-gestational-age (AGA and small-for-gestational-age (SGA VLBW infants. DESIGN AND SETTING: Prospective study in the nursery attached to the Maternity Ward of the "Prof. Pedro de Alcântara" Children's Institute, Hospital das Clínicas, Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo, Brazil. METHODS: Seventy-two VLBW infants (mean protein intake = 3.7 mg/kg/day were enrolled in a prospective cohort study in two groups: AGA (n = 34 and SGA (n = 38. Blood samples, six-hour urine (6hUr collections and urine sample tests (STUr were obtained for urea and creatinine assays at three and five weeks of life. Statistical analysis: Student's t test, Pearson correlation and linear regression (p < 0.05. RESULTS: There were no differences between groups for serum urea, 6hUr and STUr, or between two assessments within each group. Serum urea correlated with 6hUr in both AGA and SGA, and to STUr in SGA; 6hUr correlated with STUr in both AGA and SGA. There was no correlation between protein intake and serum or urine urea. CONCLUSIONS: Serum and urinary urea did not reflect protein intake when mean intakes of 3.7 g/kg/day were used. Sample tests of urinary urea can be as reliable as urea from urine collected over longer periods.

Urinary Vitamin D Binding Protein and KIM-1 Are Potent New Biomarkers of Major Adverse Renal Events in Patients Undergoing Coronary Angiography.

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Lyubov Chaykovska

Full Text Available Vitamin-D-binding protein (VDBP is a low molecular weight protein that is filtered through the glomerulus as a 25-(OH vitamin D 3/VDBP complex. In the normal kidney VDBP is reabsorbed and catabolized by proximal tubule epithelial cells reducing the urinary excretion to trace amounts. Acute tubular injury is expected to result in urinary VDBP loss. The purpose of our study was to explore the potential role of urinary VDBP as a biomarker of an acute renal damage.We included 314 patients with diabetes mellitus or mild renal impairment undergoing coronary angiography and collected blood and urine before and 24 hours after the CM application. Patients were followed for 90 days for the composite endpoint major adverse renal events (MARE: need for dialysis, doubling of serum creatinine after 90 days, unplanned emergency rehospitalization or death.Increased urine VDBP concentration 24 hours after contrast media exposure was predictive for dialysis need (no dialysis: 113.06 ± 299.61 ng/ml, n = 303; need for dialysis: 613.07 ± 700.45 ng/ml, n = 11, Mean ± SD, p<0.001, death (no death during follow-up: 121.41 ± 324.45 ng/ml, n = 306; death during follow-up: 522.01 ± 521.86 ng/ml, n = 8; Mean ± SD, p<0.003 and MARE (no MARE: 112.08 ± 302.00 ng/ml, n = 298; MARE: 506.16 ± 624.61 ng/ml, n = 16, Mean ± SD, p<0.001 during the follow-up of 90 days after contrast media exposure. Correction of urine VDBP concentrations for creatinine excretion confirmed its predictive value and was consistent with increased levels of urinary Kidney Injury Molecule-1 (KIM-1 and baseline plasma creatinine in patients with above mentioned complications. The impact of urinary VDBP and KIM-1 on MARE was independent of known CIN risk factors such as anemia, preexisting renal failure, preexisting heart failure, and diabetes.Urinary VDBP is a promising novel biomarker of major contrast induced nephropathy-associated events 90 days after contrast media exposure.

Epoxy/anhydride thermosets modified with end-capped star polymers with poly(ethyleneimine cores of different molecular weight and poly(ε–caprolactone arms

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C. Acebo

2015-09-01

Full Text Available Multiarm star polymers, with a hyperbranched poly(ethyleneimine (PEI core and poly(ε-caprolactone (PCL arms end-capped with acetyl groups were synthesized by ring-opening polymerization of ε-caprolactone from PEI cores of different molecular weight. These star polymers were used as toughening agents for epoxy/anhydride thermosets. The curing process was studied by calorimetry, thermomechanical analysis and infrared spectroscopy. The final properties of the resulting materials were determined by thermal and mechanical tests. The addition of the star polymers led to an improvement up to 130% on impact strength and a reduction in the thermal stresses up to 55%. The structure and molecular weight of the modifier used affected the morphology of the resulting materials. Electron microscopy showed phase-separated morphologies with nano-sized fine particles well adhered to the epoxy/anhydride matrix when the higher molecular weight modifier was used.

Reliability of Urinary Dehydration Markers in Elite Youth Boxers.

Science.gov (United States)

Zubac, Damir; Cular, Drazen; Marusic, Uros

2018-03-01

To determine the reliability and diagnostic accuracy of noninvasive urinary dehydration markers in field-based settings on a day-to-day basis in elite adolescent amateur boxers. Sixty-nine urine samples were collected daily from 23 athletes (17.3 ± 1.9 y) during their weight-stable phase and analyzed by field and laboratory measures of hydration status. Urine osmolality (U OSM ), urine specific gravity (U SG ), total protein content (T PC ), and body-mass stability were evaluated to determine fluid balance and hydration status. Overall macronutrient and water intake were determined using dietary records. According to their anthropometric characteristics, athletes were assigned into 2 groups: lightweight (L WB ) and heavyweight (H WB ) boxers. Data presented on U OSM demonstrated a uniform increment by 11.2% ± 12.8% (L WB ) and 19.9% ± 22.7% (H WB ) (P dehydration markers. Poor correlations were found between U SG and T PC metabolites (r = .27, P = .211). Urinary dehydration markers (both U SG and U OSM ) exhibit high variability and seem to be unreliable diagnostic tools to track actual body-weight loss in real-life settings. The ad libitum fluid intake was apparently inadequate to match acute fluid loss during and after intense preparation. The applicability of a single-time-point hydration-status assessment concept may preclude accurate assessment of actual body-weight deficits in youth boxers.

G-protein-coupled receptor 137 accelerates proliferation of urinary bladder cancer cells in vitro.

Science.gov (United States)

Du, Yiheng; Bi, Wenhuan; Zhang, Fei; Wu, Wenbo; Xia, Shujie; Liu, Haitao

2015-01-01

Urinary bladder cancer is a worldwide concern because of its level of incidence and recurrence. To search an effective therapeutic strategy for urinary bladder cancer, it is important to identify proteins involved in tumorigenesis that could serve as potential targets for diagnosis and treatment. G-protein-coupled receptors (GPRs) constitute a large protein family of receptors that sense molecules outside the cell and activate signal transduction pathways and cellular responses inside the cell. GPR137 is a newly discovered human gene encoding orphan GPRs. In this study, we aimed to investigate the physiological role of GPR137 in urinary bladder cancer. The effect of GPR137 on cell growth was examined via an RNA interference (RNAi) lentivirus system in two human urinary bladder cancer cell lines BT5637 and T24. Lentivirus-mediated RNAi could specifically suppressed GPR137 expression in vitro, resulting in alleviated cell viability and impaired colony formation, as well as blocks G0/G1 and S phases of the cell cycle. These results suggested GPR137 as an essential player in urinary bladder cancer cell growth, and it may serve as a potential target for gene therapy in the treatment of urinary bladder cancer. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

The influence of gamma radiation on the molecular weight and glass transition of PLLA and HAp/PLLA nanocomposite

International Nuclear Information System (INIS)

Milicevic, D.; Trifunovic, S.; Dojcilovic, J.; Ignjatovic, N.; Suljovrujic, E.

2010-01-01

The influence of gamma radiation on the molecular weight and glass transition behaviour of poly-L-lactide (PLLA) and hydroxyapatite/poly-L-lactide (HAp/PLLA) nanocomposite has been studied. Since PLLA exposed to high-energy radiation in the presence of air is prone to chain scission reactions and large degradation, changes in molecular weight were obtained by gel permeation chromatography (GPC). Alterations in the glass transition behaviour were investigated by differential scanning calorimetry (DSC). The apparent activation energy (ΔH*) for glass transition was determined on the basis of the heating rate dependence of the glass transition temperature (T g ). Our findings support the fact that chain scission is the main reason for the decrease of T g and ΔH* with the absorbed dose. Furthermore, more intensive chain scission degradation of PLLA was observed in HAp/PLLA and can only be ascribed to the presence of HAp nanoparticles. Consequently, initial differences in the glass transition temperature and/or apparent activation energy of PLLA and HAp/PLLA became more pronounced with absorbed dose. This study reveals that radiation-induced changes in molecular weight and glass transition temperature occur in a predictable and fairly accurate manner. Therefore, gamma radiation can be used not only for sterilization but also for tailoring desirable end-use properties of these biomaterials.

Genital and Urinary Tract Defects

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... conditions > Genital and urinary tract defects Genital and urinary tract defects E-mail to a friend Please fill ... and extra fluids. What problems can genital and urinary tract defects cause? Genital and urinary tract defects affect ...

Urinary Tract Infections (For Kids)

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Full Text Available ... Urinary Tract? Your urinary tract is actually a system made up of these main parts: two kidneys ... topic for: Kids Chronic Kidney Diseases Movie: Urinary System Your Urinary System Bedwetting View more About Us ...

Urinary Tract Infections (For Kids)

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Full Text Available ... Urinary Tract? Your urinary tract is actually a system made up of these main parts: two kidneys ... topic for: Kids Chronic Kidney Diseases Movie: Urinary System Your Urinary System Bedwetting View more Partner Message ...

Inkjet-printed gold nanoparticle surfaces for the detection of low molecular weight biomolecules by laser desorption/ionization mass spectrometry.

Science.gov (United States)

Marsico, Alyssa L M; Creran, Brian; Duncan, Bradley; Elci, S Gokhan; Jiang, Ying; Onasch, Timothy B; Wormhoudt, Joda; Rotello, Vincent M; Vachet, Richard W

2015-11-01

Effective detection of low molecular weight compounds in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is often hindered by matrix interferences in the low m/z region of the mass spectrum. Here, we show that monolayer-protected gold nanoparticles (AuNPs) can serve as alternate matrices for the very sensitive detection of low molecular weight compounds such as amino acids. Amino acids can be detected at low fmol levels with minimal interferences by properly choosing the AuNP deposition method, density, size, and monolayer surface chemistry. By inkjet-printing AuNPs at various densities, we find that AuNP clusters are essential for obtaining the greatest sensitivity. Graphical Abstract ᅟ.

URINARY TRACT INFECTIONS IN PREGNANCY

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N Sivalingam

2007-01-01

Full Text Available Urinary tract infections frequently affect pregnant mothers. This problem causes significant morbidity and healthcare expenditure. Three common clinical manifestations of UTIs in pregnancy are: asymptomatic bacteriuria, acute cystitis and acute pyelonephritis. Escherichia coli remains the most frequent organism isolated in UTIs. All pregnant mothers should be screened for UTIs in pregnancy and antibiotics should be commenced without delay. Urine culture and sensitivity is the gold standard in diagnosing UTIs. Without treatment, asymptomatic bacteriuria in pregnancy is associated with preterm delivery, intrauterine growth retardation, low birth weight, maternal hypertension, pre-eclampsia and anaemia. Acute pyelonephritis can lead to maternal sepsis. Recurrent UTIs in pregnancy require prophylactic antibiotic treatment.

Glomerular sieving of high molecular weight proteins in proteinuric rats

International Nuclear Information System (INIS)

Bertolatus, J.A.; Abuyousef, M.; Hunsicker, L.G.

1987-01-01

To characterize the permeability of the glomerular capillary wall to high molecular weight proteins in normal and proteinuric rats, we determined the glomerular sieving coefficients (GSC) of radioiodinated marker proteins of known size and charge by means of a paired label, tissue accumulation method previously validated in this laboratory. In one group of rats (Series A) the GSCs of 125 I-anionic IgG (aIgG-molecular weight [mol wt] 150,000, pI 4.9) and 131 I-neutral IgG (nIgG-pI 7.4 to 7.6) were measured simultaneously. In Series B, the GSC of a second anionic marker, 131 I-human ceruloplasmin (Crp-mol wt 137,000, pI 4.9) was compared to that of 125 I-nIgG. As in the previous report, the labeled proteins were not degraded or deiodinated during the 20 minute clearance period for GSC determination. Within Series A and B, three subgroups of rats were studied: control saline-infused rats, rats made acutely proteinuric by infusion of the polycation hexadimethrine (HDM), and rats with chronic doxorubicin (Adriamycin-Adria) nephrosis. In the control rats, GSCs for the anionic markers aIgG (Series A) or Crp (Series B) were significantly greater than that of nIgG (both series). These large proteins crossed the filtration barrier by a different pathway from that available to smaller neutral molecules the size of albumin, which in our previous study had a much higher GSC than a native, anionic albumin marker. In a third group of control rats only (Series C), the GSCs of native anionic bovine albumin (BSA) and nIgG were compared directly. The GSC of BSA (0.0029) was only slightly larger than the GSC of nIgG (0.0025), indicating that most of the native albumin crosses the glomerular capillary wall via a nonselective pathway similar to that available to nIgG. The results in the control groups are compatible with recently-described heteroporous models of glomerular size selectivity

Investigating the effects of polymer molecular weight and non-solvent content on the phase separation, surface morphology and hydrophobicity of polyvinyl chloride films

Science.gov (United States)

Khoryani, Zahra; Seyfi, Javad; Nekoei, Mehdi

2018-01-01

The main aim of this research is to study the effects of polymer molecular weight as well as non-solvent concentration on the phase separation, surface morphology and wettability of polyvinyl chloride (PVC) films. Gel permeation chromatography (GPC) results showed that the Mn of the used PVC grades is 6 × 104, 8.7 × 104 and 1.26 × 105 g/mol. It was found that a proper combination of polymer molecular weight and non-solvent content could result in superhydrophobic and self-cleaning behaviors. Scanning electron microscopy (SEM) results demonstrated that addition of ethanol causes the polymer chains to be severely aggregated at the films' surface forming strand-like structures decorated by nano-scale polymer spheres. The polymer molecular weight was found to affect the degree of porosity which is highly influential on the hydrophobicity of the films. The mechanism of phase separation process was also discussed and it was found that the instantaneous demixing is the dominant mechanism once higher contents of non-solvent were used. However, a delayed demixing mechanism was detected when the lower molecular weight PVC has been used which resulted in a pore-less and dense skin layer. Differential scanning calorimetry was also utilized to study the crystallization and glass transition behavior of samples.

The influence of polyanion molecular weight on polyelectrolyte multilayers at surfaces: elasticity and susceptibility to saloplasticity of strongly dissociated synthetic polymers at fluid-fluid interfaces.

Science.gov (United States)

Cramer, Ashley D; Dong, Wen-Fei; Benbow, Natalie L; Webber, Jessie L; Krasowska, Marta; Beattie, David A; Ferri, James K

2017-09-13

We studied the interfacial mechanical properties of polyelectrolyte multilayer assemblies of poly(diallylamine hydrochloride) (PAH) and poly(4-styrenesulfonate)sodium salt (PSS) at the air-water interface using axisymmetric drop shape analysis (ADSA) during hydrostatic inflation as a function of aqueous salt concentration and two different polyanion molecular weights (M w ∼ 13 and 70 kDa). Surface elastic moduli (G s ) ranged from 50 to 300 mN m -1 . Using the measured film thickness, the bulk moduli (G) ranged from 10 to 90 MPa consistent with elastomeric solids. This solid-like interface was evidenced by a systematic departure of the inflated shape from the Young-Laplace equation, which assumes a liquid-like interface. Surface elastic moduli increased and bulk elastic moduli decreased with increasing nanomembrane transverse dimension, and multilayers with the lower molecular weight anion were more transversely compact than those of higher molecular weight and displayed a larger elastic modulus. The bulk moduli of both types of multilayer assemblies asymptotically approach a constant value for films with more than two bilayers of polyelectrolyte, consistent with the observed transition from a 'glassy' to 'rubbery' state. Both types of multilayer assemblies displayed plasticization with increasing sodium chloride concentration in the adjoining aqueous phase, i.e. saloplasticity, and exhibited a transition from elastic to plastic response to deformation. The restored mobility of the polyelectrolyte resulting from the shift from intrinsic to extrinsic charge complexation, restores fluidity to the interface and is evidenced by experimental observation of a liquid-like interface when loaded. The higher molecular weight polyanion multilayers plasticized at lower salt concentrations suggesting that the lower melting point of the higher molecular weight polyanion assembly is attributable to a lesser extent of electrostatic cross-linking underscoring the unconventional

Urinary retention in women.

Science.gov (United States)

Juma, Saad

2014-07-01

This review is a summary of the most pertinent published studies in the literature in the last 18 months that address cause, diagnosis, and management of urinary retention in women. Symptoms, uroflow, and pressure-flow studies have a low predictive value for and do not correlate with elevated postvoid residual urine (PVR). Anterior and posterior colporrhaphy do not cause de-novo bladder outlet obstruction in the majority of patients with elevated PVR, and the cause of elevated PVR may be other factors such as pain or anxiety causing abnormal relaxation of the pelvic floor and contributing to voiding difficulty. The risk of urinary retention in a future pregnancy after mid-urethral sling (MUS) is small. The risk of urinary tract infection and urinary retention after chemodenervation of the bladder with onabotulinumtoxin-A (100 IU) in patients with non-neurogenic urge incontinence is 33 and 5%, respectively. There is a lack of consensus among experts on the timing of sling takedown in the management of acute urinary retention following MUS procedures. There has been a significant progress in the understanding of the causation of urinary retention. Important areas that need further research (basic and clinical) are post-MUS and pelvic organ prolapse repair urinary retention and obstruction, and urinary retention owing to detrusor underactivity.

Urinary Tract Infections (For Kids)

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... Staying Safe Videos for Educators Search English Español Urinary Tract Infections (UTIs) KidsHealth / For Kids / Urinary Tract Infections ( ... Let's find out more. What Exactly Is a Urinary Tract? Your urinary tract is actually a system made ...

Urinary Tract Infections (For Teens)

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... Staying Safe Videos for Educators Search English Español Urinary Tract Infections KidsHealth / For Teens / Urinary Tract Infections What's ... especially girls — visit a doctor. What Is a Urinary Tract Infection? A bacterial urinary tract infection (UTI) is ...

Kidneys and Urinary Tract

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... Videos for Educators Search English Español Kidneys and Urinary Tract KidsHealth / For Teens / Kidneys and Urinary Tract What's ... a sign of diabetes . What the Kidneys and Urinary Tract Do Although the two kidneys work together to ...

Anti-Toxoplasma activity of various molecular weights and concentrations of chitosan nanoparticles on tachyzoites of RH strain.

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Teimouri, Aref; Azami, Sanaz Jafarpour; Keshavarz, Hossein; Esmaeili, Fariba; Alimi, Rasoul; Mavi, Sara Ayazian; Shojaee, Saeedeh

2018-01-01

Natural polysaccharides such as chitosan (CS) are widely used as antimicrobial agents. In recent years, and considering that CS has a strong antimicrobial potential, interest has been focused on antimicrobial activity of chitosan nanoparticles (CS NPs). The main factors affecting the antibacterial activity of chitosan include molecular weight (MW) and concentration. In this regard, the aim of this study was to produce various MWs and concentrations of CS NPs, through the ionic gelation method, and investigate their potential anti-parasitic activity against tachyzoites of Toxoplasma gondii RH strain. The MWs and degree of deacetylation of the CS were characterized using viscometric and acid-base titration methods, respectively. The efficacy of various MWs and concentrations of NPs was assessed by performing in vitro experiments for tachyzoites of T. gondii RH strain, such as MTT assay, scanning electron microscopy, bioassay in mice and PCR. In vivo experiment was carried out in BALB/c mice which were inoculated with tachyzoites of T. gondii RH strain and treated with various MWs of CS NPs. The results of in vitro and in vivo experiments revealed that anti- Toxoplasma activity strengthened as the CS NPs concentration increased and the MW decreased. In vitro experiment showed 100% mortality of tachyzoites at 500 and 1,000 ppm concentrations of low molecular weight (LMW) CS NPs after 180 min and at 2,000 ppm after 120 min. Furthermore, a 100% mortality of tachyzoites was observed at 1,000 and 2,000 ppm concentrations of medium molecular weight (MMW) CS NPs and at 2,000 ppm concentration of high molecular weight (HMW) CS NPs after 180 min. Growth inhibition rates of tachyzoites in peritoneal exudates of mice receiving low, medium and high MWs of CS NPs were found to be 86%, 84% and 79% respectively, compared to those of mice in sulfadiazine treatment group (positive control). Various MWs of CS NPs exhibited great anti- Toxoplasma efficiency against tachyzoites of RH

An improved correlation to predict molecular weight between crosslinks based on equilibrium degree of swelling of hydrogel networks.

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Jimenez-Vergara, Andrea C; Lewis, John; Hahn, Mariah S; Munoz-Pinto, Dany J

2018-04-01

Accurate characterization of hydrogel diffusional properties is of substantial importance for a range of biotechnological applications. The diffusional capacity of hydrogels has commonly been estimated using the average molecular weight between crosslinks (M c ), which is calculated based on the equilibrium degree of swelling. However, the existing correlation linking M c and equilibrium swelling fails to accurately reflect the diffusional properties of highly crosslinked hydrogel networks. Also, as demonstrated herein, the current model fails to accurately predict the diffusional properties of hydrogels when polymer concentration and molecular weight are varied simultaneously. To address these limitations, we evaluated the diffusional properties of 48 distinct hydrogel formulations using two different photoinitiator systems, employing molecular size exclusion as an alternative methodology to calculate average hydrogel mesh size. The resulting data were then utilized to develop a revised correlation between M c and hydrogel equilibrium swelling that substantially reduces the limitations associated with the current correlation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1339-1348, 2018. © 2017 Wiley Periodicals, Inc.

Prevalence of urinary tract infection and vesicoureteral reflux in children with lower urinary tract dysfunction.

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Van Batavia, Jason P; Ahn, Jennifer J; Fast, Angela M; Combs, Andrew J; Glassberg, Kenneth I

2013-10-01

Lower urinary tract dysfunction is a common pediatric urological problem that is often associated with urinary tract infection. We determined the prevalence of a urinary tract infection history in children with lower urinary tract dysfunction and its association, if any, with gender, bowel dysfunction, vesicoureteral reflux and specific lower urinary tract conditions. We retrospectively reviewed the charts of children diagnosed with and treated for lower urinary tract dysfunction, noting a history of urinary tract infection with or without fever, gender, bowel dysfunction and vesicoureteral reflux in association with specific lower urinary tract conditions. Of the 257 boys and 366 girls with a mean age of 9.1 years 207 (33%) had a urinary tract infection history, including 88 with at least 1 febrile infection. A total of 64 patients underwent voiding cystourethrogram/videourodynamics, which revealed reflux in 44 (69%). In 119 of the 207 patients all infections were afebrile and 18 underwent voiding cystourethrogram/videourodynamics, which revealed reflux in 5 (28%). A urinary tract infection history was noted in 53% of girls but only 5% of boys (p infection history than patients with idiopathic detrusor overactivity disorder or primary bladder neck dysfunction (each p urinary tract dysfunction have a much higher urinary tract infection incidence than males. This association was most often noted for lower urinary tract conditions in which urinary stasis occurs, including detrusor underutilization disorder and dysfunctional voiding. Reflux was found in most girls with a history of febrile infections. Since reflux was identified in more than a quarter of girls with only afebrile infections who were evaluated for reflux, it may be reasonable to perform voiding cystourethrogram or videourodynamics in some of them to identify reflux. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

The Effects of Reaction Variables on Solution Polymerization of Vinyl Acetate and Molecular Weight of Poly(vinyl alcohol Using Taguchi Experimental Design

Directory of Open Access Journals (Sweden)

M.H. Navarchian

2009-12-01

Full Text Available Poly(vinyl acetate is synthesized via solution polymerization, and then it is converted to poly(vinyl alcohol by alkaline alcoholysis. The aim of the work study was to investigate statistically the  influence of reaction variables in vinyl acetate polymerization, the conversion of this monomer to polymer, degree of branching of acetyl group in poly(vinyl acetate, as well as the molecular weight of poly(vinyl alcohol, using Taguchi experimental design approach. The reaction variables were polymerization time, molar ratio of initiator to monomer, and volume ratio of monomer to solvent. The statistical analysis of variance of the results revealed that all factors have significantly influenced the conversion and degree of branching. Volume ratio of monomer to solvent is the only factor affecting the molecular weight of poly(vinyl alcohol, and has the greatest influence on all responses. By increasing this ratio, the conversion, degree of branching of acetyl group in poly(vinyl acetate, and molecular weight of poly(vinyl alcohol were increased.

Urinary Tract Infections (For Kids)

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Full Text Available ... Staying Safe Videos for Educators Search English Español Urinary Tract Infections (UTIs) KidsHealth / For Kids / Urinary Tract Infections ( ... Let's find out more. What Exactly Is a Urinary Tract? Your urinary tract is actually a system made ...

Molecular heterogeneity in major urinary proteins of Mus musculus subspecies: potential candidates involved in speciation

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Hurst, Jane L.; Beynon, Robert J.; Armstrong, Stuart D.; Davidson, Amanda J.; Roberts, Sarah A.; Gómez-Baena, Guadalupe; Smadja, Carole M.; Ganem, Guila

2017-01-01

When hybridisation carries a cost, natural selection is predicted to favour evolution of traits that allow assortative mating (reinforcement). Incipient speciation between the two European house mouse subspecies, Mus musculus domesticus and M.m.musculus, sharing a hybrid zone, provides an opportunity to understand evolution of assortative mating at a molecular level. Mouse urine odours allow subspecific mate discrimination, with assortative preferences evident in the hybrid zone but not in allopatry. Here we assess the potential of MUPs (major urinary proteins) as candidates for signal divergence by comparing MUP expression in urine samples from the Danish hybrid zone border (contact) and from allopatric populations. Mass spectrometric characterisation identified novel MUPs in both subspecies involving mostly new combinations of amino acid changes previously observed in M.m.domesticus. The subspecies expressed distinct MUP signatures, with most MUPs expressed by only one subspecies. Expression of at least eight MUPs showed significant subspecies divergence both in allopatry and contact zone. Another seven MUPs showed divergence in expression between the subspecies only in the contact zone, consistent with divergence by reinforcement. These proteins are candidates for the semiochemical barrier to hybridisation, providing an opportunity to characterise the nature and evolution of a putative species recognition signal. PMID:28337988

Preparation of Low Molecular Weight Chitosan by Radiation and its Application for Plant Growth Promoter. Chapter 10

Energy Technology Data Exchange (ETDEWEB)

Darwis, D.; Puspitasari, T.; Iramani, D.; Susilowati, Sri; Pangerteni, D.S., E-mail: darmawan_p3tir@batan.go.id [National Nuclear Energy Agency, Centre for Application of Isotopes and Radiation Technology (Indonesia)

2014-07-15

Chitosan was prepared through the alkaline deacetylation of chitin from shrimp shell waste. Chitosan with a degree of deacetylation of about 70% was produced by hot alkaline deacetylation (DDA) at 90°C for 8 hours or at room temperature deacetylation for 7 days. Through these processes, chitosan with an average molecular weight (Mw) of 141 k Dalton was obtained. Low molecular weight chitosan, Mw 14 k Dalton called “Fitosan” was prepared by irradiating chitosan using gamma rays at a dose of 75 kGy. The results showed that gamma irradiation is an effective method of degrading chitosan by cleavages of glycosidic bond. To improve crop yields and suppress diseases due to virus, bacteria, and fungi, Fitosan was successfully applied to chili, potato, and soybean. Socio-economic impacts of the use of Fitosan on the plants include increased income and improvement of the welfare of farmers. (author)

The Burden of Urinary Incontinence and Urinary Bother Among Elderly Prostate Cancer Survivors

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Kopp, Ryan P.; Marshall, Lynn M.; Wang, Patty Y.; Bauer, Douglas C.; Barrett-Connor, Elizabeth; Parsons, J. Kellogg

2014-01-01

Background Data describing urinary health in elderly, community-dwelling prostate cancer (PCa) survivors are limited. Objective To elucidate the prevalence of lower urinary tract symptoms, urinary bother, and incontinence in elderly PCa survivors compared with peers without PCa. Design, setting, and participants A cross-sectional analysis of 5990 participants in the Osteoporotic Fractures in Men Research Group, a cohort study of community-dwelling men ≥65 yr. Outcome measurements and statistical analysis We characterized urinary health using self-reported urinary incontinence and the American Urological Association Symptom Index (AUA-SI). We compared urinary health measures according to type of PCa treatment in men with PCa and men without PCa using multivariate log-binomial regression to generate prevalence ratios (PRs). Results and limitations At baseline, 706 men (12%) reported a history of PCa, with a median time since diagnosis of 6.3 yr. Of these men, 426 (60%) reported urinary incontinence. In adjusted analyses, observation (PR: 1.92; 95% confidence interval [CI], 1.15–3.21; p = 0.01), surgery (PR: 4.68; 95% CI, 4.11–5.32; p incontinence. Daily incontinence risk increased with time since diagnosis independently of age. Observation (PR: 1.33; 95% CI, 1.00–1.78; p = 0.05), surgery (PR: 1.25; 95% CI, 1.10–1.42; p = 0.0008), and ADT (PR: 1.50; 95% CI, 1.26–1.79; p urinary incontinence, which rose with increasing survivorship duration. Observation, surgery, and ADT were each associated with increased urinary bother. These data suggest a substantially greater burden of urinary health problems among elderly PCa survivors than previously recognized. PMID:23587870

Extraction of High Molecular Weight DNA from Fungal Rust Spores for Long Read Sequencing.

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Schwessinger, Benjamin; Rathjen, John P

2017-01-01

Wheat rust fungi are complex organisms with a complete life cycle that involves two different host plants and five different spore types. During the asexual infection cycle on wheat, rusts produce massive amounts of dikaryotic urediniospores. These spores are dikaryotic (two nuclei) with each nucleus containing one haploid genome. This dikaryotic state is likely to contribute to their evolutionary success, making them some of the major wheat pathogens globally. Despite this, most published wheat rust genomes are highly fragmented and contain very little haplotype-specific sequence information. Current long-read sequencing technologies hold great promise to provide more contiguous and haplotype-phased genome assemblies. Long reads are able to span repetitive regions and phase structural differences between the haplomes. This increased genome resolution enables the identification of complex loci and the study of genome evolution beyond simple nucleotide polymorphisms. Long-read technologies require pure high molecular weight DNA as an input for sequencing. Here, we describe a DNA extraction protocol for rust spores that yields pure double-stranded DNA molecules with molecular weight of >50 kilo-base pairs (kbp). The isolated DNA is of sufficient purity for PacBio long-read sequencing, but may require additional purification for other sequencing technologies such as Nanopore and 10× Genomics.

Probing the effect of polymer molecular weight on penetration into the wood cell wall using polyethylenimine (PEI) as a model compound.

Science.gov (United States)

Dorvel, Brian; Boopalachandran, Praveenkumar; Chen, Ida; Bowling, Andrew; Williams, Kerry; King, Steve

2018-05-01

Decking is one of the largest applications for the treated wood market. The most challenging property to obtain for treated wood is dimensional stability, which can be achieved, in part, by cell wall bulking, cell wall polymer crosslinking and removal of hygroscopic components in the cell wall. A commonly accepted key requirement is for the actives to infuse through the cell wall, which has a microporosity of ∼5-13 nm. Equally as challenging is being able to measure and quantify the cell wall penetration. Branched polyethylenimine (PEI) was studied as a model polymer for penetration due to its water solubility, polarity, variable molecular weight ranges, and ability to form a chelation complex with preservative metals to treat lumbers. Two different molecular weight polyethylenimines (PEI), one with a weight average molecular weight (Mw) equal to 800 Da and the other 750 000 Da, were investigated for penetration by microscopy and spectroscopy techniques. Analytical methods were developed to both create smooth interfaces and for relative quantitation and visualisation of PEI penetration into the wood. The results showed both PEI with Mw of 800 Da and PEI with Mw of 750 000 Da coated the lumens in high density. However, only the PEI with Mw of 800 appeared to penetrate the cell walls in sufficient levels. Literature has shown the hydrodynamic radii of PEI 750 000 is near 29 nm, whereas a smaller PEI at 25 K showed 4.5 nm. Most importantly the results, based on methods developed, show how molecular weight and tertiary structure of the polymer can affect its penetration, with the microporosity of the wood being the main barrier. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

Urinary Tract Infections (For Kids)

Medline Plus

Full Text Available ... Urinary Tract? Your urinary tract is actually a system made up of these main parts: two kidneys two ureters (say: ... Chronic Kidney Diseases Movie: Urinary System Your Urinary System Bedwetting View more ... & Terms of Use Notice of Nondiscrimination Visit the Nemours Web ...

Can Urinary Catheterization Before Birth Reduce Postpartum Urinary Retention?

Directory of Open Access Journals (Sweden)

Mehmet B. Şentürk

2016-04-01

Results: The time to first micturition was determined to be shorter in the group where urinary catheterization was applied before birth, the PUR rate was lower and the amount of residual urine was less (p0.05. Conclusion: Urinary catheterization before birth reduces the rate of PUR.

Determination of the linear coefficient of thermal expansion in polymer films at the nanoscale: influence of the composition of EVA copolymers and the molecular weight of PMMA.

Science.gov (United States)

González-Benito, J; Castillo, E; Cruz-Caldito, J F

2015-07-28

Nanothermal-expansion of poly(ethylene-co-vinylacetate), EVA, and poly(methyl methacrylate), PMMA, in the form of films was measured to finally obtain linear coefficients of thermal expansion, CTEs. The simple deflection of a cantilever in an atomic force microscope, AFM, was used to monitor thermal expansions at the nanoscale. The influences of: (a) the structure of EVA in terms of its composition (vinylacetate content) and (b) the size of PMMA chains in terms of the molecular weight were studied. To carry out this, several polymer samples were used, EVA copolymers with different weight percents of the vinylacetate comonomer (12, 18, 25 and 40%) and PMMA polymers with different weight average molecular weights (33.9, 64.8, 75.600 and 360.0 kg mol(-1)). The dependencies of the vinyl acetate weight fraction of EVA and the molecular weight of PMMA on their corresponding CTEs were analyzed to finally explain them using new, intuitive and very simple models based on the rule of mixtures. In the case of EVA copolymers a simple equation considering the weighted contributions of each comonomer was enough to estimate the final CTE above the glass transition temperature. On the other hand, when the molecular weight dependence is considered the free volume concept was used as novelty. The expansion of PMMA, at least at the nanoscale, was well and easily described by the sum of the weighted contributions of the occupied and free volumes, respectively.

Urinary glicosaminoglycans levels in women with urinary tract infection and non urinary tract infection

Science.gov (United States)

Pasaribu, H. P.; Hanifa, A.; Tala, R. Z.; Ardiansyah, E.; Simanjuntak, R. Y.; Effendy, I. H.

2018-03-01

UTI is an infection that occurs in the urinary tract due to the proliferation of a microorganism. Female is fourteen times more vulnerable to UTI than male, because their urethra is shorter. Bladder epithelium is coated with a thin layer of glycosaminoglycans which act as a non-specific anti-adherence factor and nonspecific defense mechanisms against infection and can be found in the urine. An analytic study with cross sectional approach was conducted in 46 patients (23 with UTI and 23 non UTI) from June 2016 to determine differences in levels of urinary glycosaminoglycans between two groups. Urine samples were taken and tested for UTI and non UTI strips test. Laboratory examination of urine GAGs levels using ELISA kit for Human Glycosaminoglycans, then tabulated and analyzed using SPSS. The result showed no significant differences in the characteristics of women between two groups. There are significant differences in the mean levels of urinary GAGs in women with UTI compared with Non-UTI (69.74 ± 21.34; 21.39 ± 2.61 mg/l; p UTI incidence, with low odds ratio values and no significant difference in the mean of urinary glicosaminoglycans level based on sexual status.

A Simple Thermoplastic Substrate Containing Hierarchical Silica Lamellae for High-Molecular-Weight DNA Extraction.

Science.gov (United States)

Zhang, Ye; Zhang, Yi; Burke, Jeffrey M; Gleitsman, Kristin; Friedrich, Sarah M; Liu, Kelvin J; Wang, Tza-Huei

2016-12-01

An inexpensive, magnetic thermoplastic nanomaterial is developed utilizing a hierarchical layering of micro- and nanoscale silica lamellae to create a high-surface-area and low-shear substrate capable of capturing vast amounts of ultrahigh-molecular-weight DNA. Extraction is performed via a simple 45 min process and is capable of achieving binding capacities up to 1 000 000 times greater than silica microparticles. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Modification of polyelectrolyte microcapsules into a container for the low molecular weight compounds

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Goryacheva, O. A.; Gao, H.; Sukhorukov, G. B.

2018-04-01

Polyelectrolyte microcapsules are one of the most successful developments in the direction of target drug delivery. Nevertheless, to encapsulate low molecular weight compounds and to deliver the targeted drugs it is necessary to modify the surface of the microcapsules. Silica nanostructures obtained as result of hydrolysis of (3-Aminopropyl)- triethoxysilane (APTES) were used for the modification of the microcapsules. This material shows no toxic effect on cells and is capable of biodegradation. Amino-groups in the structure of APTES make it possible for further direct bioconjugation.

Vitamin K antagonists or low-molecular-weight heparin for the long term treatment of symptomatic venous thromboembolism

NARCIS (Netherlands)

van der Heijden, J. F.; Hutten, B. A.; Büller, H. R.; Prins, M. H.

2000-01-01

Patients who have had an episode of symptomatic venous thromboembolism are usually treated for at least five days with intravenous unfractionated heparin or subcutaneous low-molecular-weight heparin. Thereafter, they received a three month course of a vitamin K antagonist, with a dose adjusted to

[Urinary incontinence and pregnancy].

Science.gov (United States)

Deffieux, X

2009-12-01

The goal of the current study was to systematically review the literature concerning urinary incontinence and pregnancy, in order to develop recommendations for clinical practice. The prevalence of urinary stress incontinence and overactive bladder symptoms increase with gestational age during pregnancy (from the first to the third trimester), and decrease during the third months following delivery. Obstetrics factors (position during delivery, length of the second part of the labour, forceps, episiotomy, epidural or pudendal anaesthesia) do not modify the risk of post-partum or long term urinary incontinence. At short term follow-up, caesarean delivery is associated with a lower rate of post-partum urinary incontinence. At long term follow-up, data are lacking. Non elective caesarean section is not associated with a decrease in the rate of post-partum or long-term urinary incontinence. Elective caesarean section and systematic episiotomy are not recommended methods for the prevention of post-partum urinary incontinence (grade B), even in "high risk" women. Pelvic floor muscle therapy is the first line treatment for prenatal or post-partum urinary incontinence (grade A). Copyright © 2009 Elsevier Masson SAS. All rights reserved.

Analysis of sulfates on low molecular weight heparin using mass spectrometry: structural characterization of enoxaparin.

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Gupta, Rohitesh; Ponnusamy, Moorthy P

2018-05-21

Structural characterization of Low Molecular Weight Heparin (LMWH) is critical to meet biosimilarity standards. In this context, the review focuses on structural analysis of labile sulfates attached to the side-groups of LMWH using mass spectrometry. A comprehensive review of this topic will help readers to identify key strategies for tackling the problem related to sulfate loss. At the same time, various mass spectrometry techniques are presented to facilitate compositional analysis of LMWH, mainly Enoxaparin. Areas covered: This review summarizes findings on mass spectrometry application for LMWH, including modulation of sulfates, using enzymology and sample preparation approaches. Furthermore, popular open-source software packages for automated spectral data interpretation are also discussed. Successful use of LC/MS can decipher structural composition for LMWH and help evaluate their sameness or biosimilarity with the innovator molecule. Overall, the literature has been searched using PubMed by typing various search queries such as "enoxaparin", "mass spectrometry", "low molecular weight heparin", "structural characterization", etc. Expert commentary: This section highlights clinically relevant areas that need improvement to achieve satisfactory commercialization of LMWHs. It also primarily emphasizes the advancements in instrumentation related to mass spectrometry, and discusses building automated software for data interpretation and analysis.

A sulfuric-lactic acid process for efficient purification of fungal chitosan with intact molecular weight.

Science.gov (United States)

Naghdi, Mitra; Zamani, Akram; Karimi, Keikhosro

2014-02-01

The most recent method of fungal chitosan purification, i.e., two steps of dilute sulfuric acid treatment, pretreatment of cell wall at room temperature for phosphate removal and extraction of chitosan from the phosphate free cell wall at high temperature, significantly reduces the chitosan molecular weight. This study was aimed at improvement of this method. In the pretreatment step, to choose the best conditions, cell wall of Rhizopus oryzae, containing 9% phosphate, 10% glucosamine, and 21% N-acetyl glucosamine, was treated with sulfuric, lactic, acetic, nitric, or hydrochloric acid, at room temperature. Sulfuric acid showed the best performance in phosphate removal (90%) and cell wall recovery (89%). To avoid depolymerisation of chitosan, hot sulfuric acid extraction was replaced with lactic acid treatment at room temperature, and a pure fungal chitosan was obtained (0.12 g/g cell wall). Similar pretreatment and extraction processes were conducted on pure shrimp chitosan and resulted in a chitosan recovery of higher than 87% while the reduction of chitosan viscosity was less than 15%. Therefore, the sulfuric-lactic acid method purified the fungal chitosan without significant molecular weight manipulation. Copyright © 2013 Elsevier B.V. All rights reserved.

Developing a Macroscopic Mechanistic Model for Low Molecular Weight Diffusion through Polymers in the Rubbery State

DEFF Research Database (Denmark)

Martinez-Lopez, Brais; Huguet, P.; Gontard, N.

2016-01-01

Raman microspectroscopy was used to determine the Fickian diffusivity of two families of low molecular weight molecules through amorphous polystyrene in the rubbery state. Different effects of the temperature on diffusivity for each of the families suggested that molecular mobility is controlled...... by both the volume and flexibility of the diffusing substance when the movement of polymer chains can generate stress induced deformation of molecules. The diffusing molecules were represented as Newtonian spring–bead systems, which allowed us to quantify their flexibility, in function of the vibration...... frequency of their bonds by reconstructing their theoretical spectra. Results showed that the use of molecular descriptors that take into account flexibility rather than the most stable conformation of the diffusing molecules may improve the description of the diffusion behavior caused by variations...

Concepts in causality: chemically induced human urinary bladder cancer

International Nuclear Information System (INIS)