bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective separation of some ecotoxic transition metal ions from aqueous solutions using immobilized macrocyclic material containing solid phase extraction system
Authors: Rahman Ismail , Furusho Yoshiaki , Begum Zinnat , Sabarudin Akhmad , Motomizu Shoji , Maki Teruya , Hasegawa Hiroshi 
Published: August 2011

AbstractA simple flow-based method was developed for the simultaneous separation of certain transition metal ions (Co, Ni, Cu, Zn, Cd) from aqueous systems, which ions show ecotoxic effects when present at elevated concentrations. A silica-gel-bonded macrocycle system, commonly known as molecular recognition technology (MRT) gel, was used for solid phase extraction (SPE) of the target analytes. The collection behavior of the MRT-SPE system was studied based on pH. Fortified deionized water samples containing 250 µg L−1 of each of the elements were treated at the flow rate of 1 mL min−1. The collected analytes were then eluted by 3 M HNO3 and analyzed using inductively coupled plasma spectrometry. Detection limits of the proposed technique were in the range of 0.004–0.040 µg L−1 for the studied metal ions. The validity of this separation technique was checked with spiked ‘real’ water samples, which produced satisfactory recoveries of 96–102%. The non-destructive nature and highly selective ion-extraction capability of the SPE material are the most important aspects of the proposed method and they are the main focus of this paper.
Determination of four trace preservatives in street food by ionic liquid-based dispersive liquid-liquid micro-extraction
Authors: Yang Peng , Ren Haixia , Qiu Hongdeng , Liu Xia , Jiang Shengxiang 
Published: August 2011

AbstractA rapid and simple ionic liquid-based dispersive liquid-liquid micro-extraction (DLLME) method has been developed to pre-concentrate four paraben preservatives (methylparaben, ethylparaben, propylparaben, and butylparaben) from street food (pancakes). Several potentially influential factors such as the type of ionic liquid and disperser solvent, extraction time, sample pH, ionic strength, and the volume of the ionic liquid and disperser solvent were investigated. The optimum experimental conditions for the proposed micro-extraction process were: 0.1 mL of 1-octyl-3-methylimidazolium hexafluorophosphate ([C8MIM][PF6]) as an extraction solvent, 0.1 mL of acetonitrile as a disperser solvent, 5 min extraction time, and sample ionic strength of 30 % sodium chloride in water sample at pH 6.0. The LODs and LOQs were in the range of 1.0–1.5 ng g−1 and 3.5–4.5 ng g−1, respectively. Spiking recoveries were in the range of 60.1–79.5 % and the associated RSDs were all in the range of 1.8–7.0 %. The results show that DLLME is a suitable method for the determination of parabens in pancake samples and ionic liquid is a good extractant in this process.
Facile synthesis of 3-aryl-1-((4-aryl-1,2,3-selenadiazol-5-yl)sulfanyl)isoquinolines
Authors: Prabakaran Kamalakannan , Khan Fazlur-Rahman , Jin Jong , Jeong Euh , Manivel Pitchai 
Published: August 2011

AbstractA new series of 1,2,3-selenadiazoles containing an aryl or a 3-arylisoquinoline sulfanyl moiety at carbons 4 and 5, respectively, was prepared by cyclization of the respective semicarbazones in the presence of selenium(II) oxide and tetrahydrofuran at 70–75°C. Semicarbazones required for the reaction were obtained from 2-((3-arylisoquinolin-1-yl)sulfanyl)-1-phenylethanones, I, by a reaction with semicarbazide hydrochloride in ethanol/water mixture and potassium acetate base.
Toxicity reduction of 2-(5-nitrofuryl)acrylic acid following Fenton reaction treatment
Authors: Mackuľak Tomáš , Olejníková Petra , Prousek Josef , Švorc Ľubomír 
Published: August 2011

AbstractMonitoring the enforcement of an EU-wide ban of nitrofuran antibiotics in the food production chain is a challenging task, given the nature of nitrofuran compounds. The original and modified Fenton reactions are advanced oxidation processes that can eliminate the toxicity of nitrofurans. 2-(5-Nitrofuryl)acrylic acid (I) was degraded as a model compound by the original Fenton reaction with ferrous sulphate, by Mohr’s salt at pH 3 and 7, and finally by advanced Fenton process (AFP) (Fe0/H2O2/H2SO4). In addition, the growth inhibition of Escherichia coli, a G− bacterium, was tested both before and after AFP treatment. The results showed that a small degradation efficiency of this treatment process led to the toxicity changes and that the toxicity of I after AFP treatment process decreased. It seems that the treatment of polluted water using the Fenton reaction and its modifications would be a suitable method for degradation of nitrofuran derivatives in polluted water.
Extraction of phytosterols from tall oil soap using selected organic solvents
Authors: Rousková Milena , Heyberger Aleš , Tříska Jan , Krtička Miroslav 
Published: August 2011

AbstractTall oil soap as a waste product of the sulphate cellulose production process was treated by single-stage liquid-liquid extraction. The aim of this study was to compare yields of health beneficial matters contained in tall oil soap when several extraction solvents, recommended in literature, were used. Hexane, 1-methyl-4-(1-methylethenyl)-cyclohexene, 2-methylpropan-1-ol, hexan-1-ol, 4-methylpentan-2-one, 2-methoxy-2-methylpropane, and butyl ethanoate were tested. For hydrocarbons it was necessary to add a de-emulsifier into the system, which limits the formation of foams and stable emulsions. The highest yields of total phytosterols (78 %) and especially of β-sitosterol (100 %) were reached when butyl ethanoate was used. However, it was necessary to adjust pH of the treated raw material to approximately 7. The highest yields for feed where pH was not adjusted were obtained with 2-methylpropan-1-ol: 67 % of total sterols and 89 % of β-sitosterol. Disadvantages of most of the tested solvents included the formation of the undesirable solid interphase which could not be removed, partial solubility of the solvents in the water phase, their high boiling point and/or instability. These disadvantages prevent the use of these solvents in industrial applications; they also complicate the treatment of tall oil soap by liquid-liquid extraction or the regeneration of the used organic solvent.
Optimisation and validation of liquid chromatographic and partial least-squares-1 methods for simultaneous determination of enalapril maleate and nitrendipine in pharmaceutical preparations
Authors: Caglayan Mehmet , Palabiyik Ismail , Bor Mustafa , Onur Feyyaz 
Published: August 2011

AbstractSimultaneous determination of enalapril maleate (ENA) and nitrendipine (NIT) in pharmaceutical preparations was performed using liquid chromatography (LC) and the partial least-squares-1 (PLS-1) method. In LC, the separation was achieved on a C8 column and the optimum mobile phase for good separation in a gradient elution programme was found to be acetonitrile-water (φ r = 81: 19) and optimum flow-rate, temperature, injection volume, and detection wavelength were set at 1.0 mL min−1, 25°C, 10 μL, and 210 nm, respectively. Dienogest was selected as an internal standard. In the spectrophotometry, a PLS-1 chemometric method was used. The absorbance data matrix related to the concentration data matrix was established by measurement of absorbances in their zero order spectra with an increment of Δλ = 1 nm in the 220–290 nm range for ENA and with Δλ = 1 nm in the 230–290 nm range for NIT in the PLS-1 method. Following this step, calibration was established by using this data matrix to predict the unknown concentrations of ENA and NIT in their binary mixture. These optimised methods were validated and successfully applied to a pharmaceutical preparation in tablet form and the results were subjected to comparison.
Synthesis and characterisation of alkaline earth-iron(III) double hydroxides
Authors: Sipiczki Mónika , Srankó Dávid , Kukovecz Ákos , Kónya Zoltán , Sipos Pál , Pálinkó István 
Published: August 2011

AbstractDouble hydroxides containing alkaline earth and iron(III) ions were synthesised by the co-precipitation method. The solid materials obtained were characterised by a range of instrumental methods (powder X-ray diffractometry, thermogravimetry, scanning electron microscopy, energy dispersive X-ray fluorescence spectrometry, elemental maps, and infrared spectroscopy). It was found that the Ca(II)Fe(III), Mg(II)Fe(III), and Ba(II)Fe(III) double hydroxides had layered structures, while Sr(II)Fe(III) had not. The optimum conditions for synthesis of Ca(II)Fe(III)-layered double hydroxides (materials to be used in further studies) were also elaborated.
Chemiluminescence parameters of peroxynitrous acid in the presence of short-chain alcohols and Ru(bpy)32+
Authors: Wei Lijun , Xia Huifen , Wang Zhaopin , Yuan Ping , Zhou Tong , Zhang Baojun , Cheng Xianglei 
Published: August 2011

AbstractThe chemiluminescence behaviour and mechanism of peroxynitrous acid and Ru(bpy)32+ were studied in the presence of short-chain alcohols (methanol, ethanol, propan-1-ol, propan-2-ol, butanol, 2-methylpropan-1-ol, pentanol). It was found that the chemiluminescence intensity of peroxynitrous acid and Ru(bpy)32+ system could be significantly enhanced by these seven short-chain alcohols. The maximum chemiluminescence wavelength of 608 nm of [Ru(bpy)32+]* in the excited state was attributed to the reaction between Ru(bpy)32+ and dihydroxyalkyl radicals which were generated during the redox course of peroxynitrous acid and alcohols. In addition, the chemiluminescence signals of the system presented depended largely on the solubility and branched-chain structure as well as the length of carbon chain. The analytical characteristics and parameters of the peroxynitrous acid/Ru(bpy)32+/alcohols chemiluminescence system were investigated under optimum conditions.
2-Alkylsulphanyl-4-pyridinecarbothioamides — inhibitors of oxygen evolution in freshwater alga Chlorella vulgaris
Authors: Kráľová Katarína , Šeršeň František , Klimešová Věra , Waisser Karel 
Published: August 2011

AbstractThe inhibition of the oxygen evolution rate (OER) in Chlorella vulgaris by 2-alkylsulphanyl-4-pyridinecarbothioamides (APCTs; alkyl = methyl up to hexadecyl) was studied. APCTs were found to inhibit photosynthetic electron transport (PET) which resulted in the inhibition of OER in algae. The inhibitory activity of APCTs was highly dependent on the alkyl chain length of the 2-alkylsulphanyl substituent and the corresponding dependence showed a bilinear course with the decyl derivative as being the most active inhibitor. Using EPR spectroscopy, the site of APCT action in the algal photosynthetic apparatus was determined. It was confirmed that APCT interacted mainly with the D. intermediate, i.e. with tyrosine radical (TyrD) occurring at the 161st position in D2 protein which is situated on the donor side of photosystem 2.
Influence of trimethoxy-substituted positions on fluorescence of heteroaryl chalcone derivatives
Authors: Suwunwong Thitipone , Chantrapromma Suchada , Fun Hoong-Kun 
Published: August 2011

AbstractThree series of heteroaryl chalcones, (E)-1-(2-pyridyl)-3-(X)prop-2-en-1-one (Ia-Ic), (E)-1-(2-thienyl)-3-(X)prop-2-en-1-one (IIa-IIc), and (E)-1-(2-furyl)-3-(X)prop-2-en-1-one (IIIa-IIIc), where X = 2,4,5-trimethoxyphenyl (for series a), X = 2,4,6-trimethoxyphenyl (for series b), and X = 3,4,5-trimethoxyphenyl (for series c) were synthesised using basic catalysed aldol condensation and characterised using 1H NMR and FT-IR spectroscopies. Compound IIa was also characterised by single crystal X-ray analysis. The absorption and fluorescence emission spectra of these compounds revealed that the absorption and fluorescence depended on the heterocycle rings and trimethoxysubstituted phenyl rings linked to the enone system. The position of methoxy groups substantially affected the fluorescent properties. Compounds Ia-IIIa containing the 2,4,5-trimethoxyphenyl moiety exhibited the red-shift phenomenon and strong emission fluorescence.
Modelling of sorbic acid diffusion through bacterial cellulose-based antimicrobial films
Authors: Dobre Loredana-Mihaela , Stoica-Guzun Anicuţa , Stroescu Marta , Jipa Iuliana , Dobre Tǎnase , Ferdeş Mariana , Ciumpiliac Ştefana 
Published: August 2011

AbstractAntimicrobial packaging protects the product from the external environment and microbial contamination, conferring numerous advantages on human health. Interest in biopolymers as packaging materials has considerably increased recently. Bacterial cellulose is an interesting biomaterial produced as nanofibrils by Acetobacter xylinium and is a promising candidate due to its remarkable properties. New composite materials with antimicrobial properties were developed in this work, containing poly(vinyl alcohol) (PVA) as polymer matrix and ground bacterial cellulose (BC) as reinforcing fibres. Sorbic acid was used as an antimicrobial agent because it is a preservative recognised in the food industry. The materials obtained were studied using Fourier-transformed infrared spectroscopy (FTIR). The swelling rate of the composites was also measured. Release experiments of sorbic acid from the composite films into water were performed and the mass transfer phenomena were investigated using Fick’s law of diffusion. The antimicrobial effect was tested against Escherichia coli K12-MG1655. The results obtained indicated that the new biocomposite films could be promising antimicrobial food packaging materials.
Ethanol production in a bioreactor with an integrated membrane distillation module
Authors: Barancewicz Marta , Gryta Marek 
Published: August 2011

AbstractEthanol production in a bioreactor with integrated membrane distillation (MD) module has been investigated. A hydrophobic capillary polypropylene membrane (Accurel PP V8/2 HF), with an external/internal diameter ratio, d out/d in = 8.6 mm/5.5 mm and pore size 0.2 μm, was used in these studies. The products (mainly ethanol and acetic acid) formed during the fermentation of sugar with Saccharomyces cerevisiae inhibited the process. These products were selectively removed from the fermentation broth by the MD process, which increased the efficiency of the conversion of sugar to alcohol from 0.45 g to 0.5 g EtOH per g of fermented sucrose. The bioreactor efficiency also increased by almost 30 %. Separation of alcohol by the MD generates a higher yield of ethanol in the permeate than in the broth. The enrichment coefficient amounted to 4-8, and depended on the ethanol concentration in the broth. The separated solutions did not wet the membrane in use for 2500 h of the MD experiments and the retention of inorganic solutes was close to 100 %.
Biochemical Effects of Low-Flow Anesthesia with Inhalation agents in Patients undergoing Laparoscopic Surgery
Authors: Sivaci Remziye , Demir Serap , Koken Tulay , Sivaci Yasar , Yilmaz Sezgin 
Published: August 2011

Biochemical Effects of Low-Flow Anesthesia with Inhalation agents in Patients undergoing Laparoscopic SurgeryThis study was designed to investigate the effects of low-flow anesthesia with sevoflurane and desflurane on renal and hepatic functions in patients undergoing laparoscopic abdominal surgery. Twenty patients with ASA I or II (American Society of Anesthesiologists classification) physical scores were included in the study. There were no significant differences between sevoflurane and desflurane groups with respect to age, weight, body mass index, duration of the operation and the anesthesia. In both groups, renal function parameters such as urea, BUN, creatinine and calculated creatinine clearance did not show significant differences at 24 and 48 hours. Homocysteine levels, which showed renal metabolic function, did not change significantly at 24 and 48 hours when compared to baseline levels in both groups. Transaminases were not significantly different between the two groups from baseline to 24 and 48 hours. These differences between the preoperative and postoperative values of biochemical parameters were similar for both anesthetic groups (p>0.05). Low-flow anesthesia did not cause impairment in terms of renal and hepatic functions.
CD20 Expression in the Transplanted Kidney of Patients with Graft Loss and Transient Allograft Dysfunction
Authors: Han Yong , Shi Bingyi , Cai Ming , Xu Xiaoguang , Xu Liang , Wang Qiang , Zhou Wenqiang , Xiao Li 
Published: August 2011

CD20 Expression in the Transplanted Kidney of Patients with Graft Loss and Transient Allograft DysfunctionThis study aimed to explore the relationship between the infiltration of CD20+ B cells and the survival time of a renal allograft and to investigate the role of infiltrated B cells in the rejection of the renal allograft. A total of 40 patients with renal allograft loss due to refractory rejection and 20 patients with transient renal allograft dysfunction were recruited. Renal biopsy was done and CD20 expression was detected by immunohistochemistry. In addition, the survival time of the renal allograft was also obtained. The relationships between the CD20 expression and the survival time of the renal allograft and graft loss due to rejection were analyzed. The associations of gender, age and clinicopathogical types with the CD20 expression were also investigated. The proportion of patients positive for CD20 in the transplanted kidney was higher in patients receiving nephrectomy of the allograft due to rejection than in those with transient allograft dysfunction. The diffuse infiltration of CD20+ B cells was considered as positive staining. In 40 samples from patients with graft loss, 19 had diffuse infiltration of CD20+ B cells (47.5%). In 19 patients positive for CD20, hyperacute rejection was found in 1 patient, acute rejection in 5 and chronic rejection in 13. Statistical analysis showed the CD20 expression was not associated with the age and gender of donors and recipients, regimen for immunosuppressive treatment, cold/warm ischemia time and secondary transplantation. CD20+ B cell infiltration predicts a poor prognosis of patients with kidney transplantation and is one of the risk factors of graft loss.
Impact of Transitory Hyperprolactinemia on Clinical Outcome of In Vitro Fertilization and Embryo Transfer
Authors: Zhong Yi-ping , Shen Xiao-ting , Ying Ying , Wu Hai-tao , Li Jin , Qi Quan , Zhou Can-quan , Zhuang Guang-lun 
Published: August 2011

Impact of Transitory Hyperprolactinemia on Clinical Outcome of In Vitro Fertilization and Embryo Transfer
This study aimed to evaluate the impact of serum prolactin concentration at the day of human chorionic gonadotropin (HCG) administration on the clinical outcome of in vitro fertilization and embryo transfer (IVF-ET). A total of 184 patients receiving the IVF-ET/ICSI-ET from October 2005 to March 2008 were retrospectively analyzed. Subjects were divided into four groups according to the serum prolactin concentration [<30 ng/mL (A), 30-60 ng/mL (B), 60-90 ng/mL (C), ≥90 ng/mL (D)] on the day of HCG administration during controlled ovarian stimulation (COS). In the Groups A, B, C and D, the implantation rate was 11.76%, 19.71%, 12.72% and 2.22%, respectively, and the pregnancy rate (PR) was 25.00%, 42.70%, 27.30% and 5.88%, respectively. The implantation rate and PR in the Group D were markedly lower than those in the remaining groups (P=0.011 and 0.009). During the COS, the serum prolactin concentration was dramatically elevated when compared with the baseline level leading to transient hyperprolactinemia. In addition, the implantation rate and pregnancy rate were significantly markedly decreased when the serum prolactin concentration was remarkably increased (≥90 ng/mL). To improve the clinical pregnancy rate of IVF-ET, close monitoring and appropriate intervention are needed for patients with an abnormal prolactin level during the COS.
Expressions of sFRP1 and β-Catenin in Cervical Cancer
Authors: Zhang Xiao-yan , Wang Lin , Qiao Yuhuan , Guo Ruixia 
Published: August 2011

Expressions of sFRP1 and β-Catenin in Cervical Cancer
This study aimed to investigate the expressions of secreted frizzled-related protein 1 (sFRP1) and β-catenin in cervical cancer and cervical intraepithelial neoplasia (CIN), and to explore the relationship between both proteins and the prognosis of cervical cancer. Immunohistochemistry was performed to detect the protein expressions of sFRP1 and β-catenin in cervical cancer (n=78), CIN (n=30) and normal cervical tissues (n=20), and the relationships of sFRP1 and β-catenin with the clinicopathological characteristics and prognosis of cervical cancer were analyzed. The positive rate of sFRP1 was 100%, 70% and 33.3% in the normal cervical tissues, CIN and cervical cancer, respectively (P<0.05). The sFRP1 expression was positively correlated with the stage of cervical cancer and lymphatic metastasis (P<0.05). The 5-year survival rate was significantly higher in patients positive for sFRP1 than in those negative for sFRP1 (P<0.05). The rate of abnormal β-catenin expression in the normal cervical tissues, CIN and cervical cancer was 5%, 43.3% and 70.5%, respectively (P<0.05). The abnormal β-catenin expression was positively correlated with the stage of cervical cancer, lymphatic metastasis and pathological grade (P<0.05). The 5-year survival rate was markedly higher in patients with normal β-catenin expression than in those with abnormal β-catenin expression (P<0.05). The sFRP1 expression was negatively related to the β-catenin expression in cervical cancer (r = -0.557, P<0.001). Both sFRP1 and β-catenin play important roles in the initiation and development of cervical cancer, and both proteins can be used as indicators predicting the prognosis of cervical cancer.
Biochemical and Physiological Characteristics of Neonates Born to Mothers with Diabetes During Gestation
Authors: Milašinović Ljubomir , Hrabovski Ivan , Grujić Zorica , Bogavac Mirjana , Nikolić Aleksandra 
Published: August 2011

Biochemical and Physiological Characteristics of Neonates Born to Mothers with Diabetes During GestationThe aim of this study was to investigate how glucose homeostasis disorders influence biochemical homeostasis and fetal maturation. A prospective randomized study included 102 infants: 31 newborns of mothers with glucose homeostasis disorders (Group I) and 71 newborns of healthy mothers (Group II). In the pregnant women, the mean age, body weight and height, BMI, parity, duration of the disease and the mode of labor were estimated. The following procedures were performed in each newborn infant: physical examination, determination of Apgar score, measurements of birth weight and length, estimation of neurological status, clinical estimation of gestational age, ECG and ultrasonography of the brain, as well as the basic hematologic, biochemical and microbiological analyses. Newborn infants of diabetic pregnancies were small for gestational age and of high birth weight. The levels of Na+, K+and Cl-ions did not show significant differences between the investigated groups, whereas the levels of total Ca and Mg were significantly decreased (2.18±0.59 and 0.65±0.17 mmol/L) (p<0.001) in the investigated group relative to the control group (2.42±0.53 and 0.81±0.09 mmol/L). The newborn infants of diabetic pregnancies presented with significantly decreased values of phosphates, bicarbonates and pH, whereas the difference in total osmolality was not statistically significant. The level of glucose at birth in the infants of diabetic mothers was lower (2.91±0.51 mmol/L) (p<0.001) than in the infants of healthy pregnancies (3.94±0.29 mmol/L). Glycemia lower than 2 mmol/L was recorded in 6.5% of infants of the investigated group. The level of bilirubin was significantly increased (209.71±56.66 mmol/L) (p<0.001) in infants of diabetic mothers compared to those of the healthy ones (155.70±61.14 mmol/L), like the incidence of clinically manifested hyperbilirubinemia. Disorders of maternal glucose homeostasis cause biochemical disorders such as hypoglycemia, hypocalcemia, hyperbilirubinemia, hypomagne semia and are associated with impaired maturation and congenital malformations of the fetus.