生物物理化学(英文)最新文献

{"title":"Surface tensometry studies on formulations of surfactants with preservatives as a tool for antimicrobial drug protection characterization","authors":"S. Pogorzelski, D. Watrobska-Swietlikowska, M. Sznitowska","doi":"10.4236/JBPC.2012.34040","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34040","url":null,"abstract":"The aim of the work was to quantify possible interactions between surfactants and preservatives, comparing surface properties, in model pharmaceutical formulations. Surface parameters of 2-component surfactant-preservative aquous mixtures were determined with a Wilhelmy plate technique, for the so-called principal surfactants (polysorbate 80, egg lecithin, phosphatidylcholine) and preservatives, which were methylparaben and benzalkonium chloride (BA-C). A generalized surface tension vs. surfactant concentration plot signatures, in the presence of preservative at a fixed amount, allowed: the critical micellar concentration (cmc) shift, additive molecules partition from the surface to the bulk, mixed micelles formation concentration, and additive surface removal concentration to be determined in reference to surface activity of the added substance. Methylparaben is a compound of lower (in comparison to BAC) surface activity, lower partitioning coefficient possessing lower energy and concentration of its removal from the surface, that makes it play effectively an antimicrobial protection role in the bulk of pharmaceutical products, as already shown by chemical tests.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of petroleum refining activities on nitrate and nitrite content of edible vegetables and on their in vivo kinetics in albino rats","authors":"G. Otti, P. N. Okafor","doi":"10.4236/JBPC.2012.34032","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34032","url":null,"abstract":"The influence of pollution from petroleum refining activities on the levels of nitrates and nitrites in five edible vegetable species was investigated. Besides, the kinetics of nitrite and nitrate was studied in vivo using albino rats with focus on the possible influence of concentration difference on kinetics and implications to toxicity. Leaf samples of the five vegetable species were collected randomly from various locations within Eleme, a host community of Port Harcourt Refinery Company and the Indorama Petrochemical Company. Also, samples were collected from Umuahia, which served as pollution-free control. The leaf samples were analyzed for their nitrite and nitrate contents. Nitrite was determined spectrophotometrically while nitrate was determined after cadmium column reduction. Results showed that samples from Eleme had higher mean nitrate (349.20 mg/100g dry leaf mass; P 0.05) as compared to the same samples from Umuahia. Solutions of nitrate and nitrite, equivalent in concentration to mean nitrate and nitrite content of the vegetable samples from the two locations were administered enterally to four groups of albino rats. Analysis of their blood levels were monitored five times at 30 minutes intervals following administration. Rates of change of blood nitrites and nitrates were found to be fairly constant in absorption as well as in the elimination phase. Their peak blood concentrations varied proportionately with their concentrations in administered solutions. However, peak blood nitrate was attained later in group of animals receiving higher amount of nitrate solution. Refining activities may pre-dispose people living within Eleme community to health hazards through contamination of edible vegetables.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of chromium ions on the growth of the calcium hydroxyapatite crystal","authors":"S. Sallam, Khairi M. Tohami, A. Sallam, L. I. A. Salem, F. A. Mohamed","doi":"10.4236/JBPC.2012.34034","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34034","url":null,"abstract":"Hydroxyapatite (Ca10(PO4)6(OH)2) is widely used as bio-ceramic materials and as adsorbents for separation of bio-molecules. These materials have also been used as adsorbents for heavy metals, supports and as catalysts in oxidation and dehydrogenation reactions. The catalytic performance of these materials depend on the lattice substitution of Ca sites in Hydroxyapatite structure by varied cations as Na, Mg, Sr and Mn, which result in changes in various structural pro perties as crystallinity and morphology. Pure calcium hydroxyapatite (S1) and Cr loaded hydroxyl apatite (S2, S3, S4 and S5) of different chromium concentrations have been prepared by wet precipitated method. An in-vitro examination is essential to investigate the mechanism of the deficient HA and tissue interface reaction by preparing SBF (Simulated Body Fluid) through the elemental and chemical analysis of Ca, P and Cr. FTIR used to analyze the samples after incubation in SBF for 24 day. PH of the samples also was measured at the first period of immersion time. At high loading of chromium ions, the formation of carbonate apatite decrease. The concentrations of the chromium in the Cr_HA crystal during the soaking in SBF are very safe dose for human.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tityus serrulatus venom and its toxins Ts1 and Ts5 increase cytosolic Ca2+ concentration in isolated vascular smooth muscle cells","authors":"M. A. Neto, F. Vasconcelos, L. Bendhack, E. Arantes","doi":"10.4236/JBPC.2012.34035","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34035","url":null,"abstract":"Voltage-gated Na+ channel (Nav channel) scorpion toxins are classified as α- and β-neurotoxins. Ts5 (α-neurotoxin) and Ts1 (β-neurotoxin) from Tityus serrulatus venom (TsV) interact with Nav channels, increasing Na+ influx and activating voltage-dependent Ca2+ channels. This study aimed to investigate the effect of TsV, Ts1 and Ts5 on the cytosolic Ca2+ concentration ([Ca2+]C) in rat aortic smooth muscle cells. Toxins were isolated by ion exchange chromatography (Ts1) followed by RP-HPLC (Ts5). The rat aortic smooth muscle cells were isolated in Hanks buffer pH 7.4 and loaded with 5 μmol/L of Fura-2AM (45 minutes at 37℃), in order to measure [Ca2+]C by fluorescence of Fura-2/AM (ratio 340/380 nm). The fluorescence was measured in one single cell (excitation: 340 and 380 nm; emission: 510 nm). TsV (100 and 500 mg/mL) and its toxins Ts1 and Ts5 (50 and 100 mg/mL each) led to a concentration-dependent increase in [Ca2+]C. Tetrodotoxin (1 mmol/L), a Nav channel blocker, and verapamil (1 mmol/L), a voltage-operated Ca2+ channel blocker, inhibited the increase in [Ca2+]C induced by TsV (500 mg/mL). In conclusion, TsV and its toxins induce a concentration-dependent increase in [Ca2+]C that probably occurs through interaction with Nav channels, thus inducing depolarization and consequent Ca2+ influx. This assumption is based on the fact that this effect is inhibited by tetrodotoxin and verapamil, showing a direct action of TsV toxins on aorta smooth muscle cells.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent enhancement of the immunity in AIDS and other immunocompromised patients by hyperforin an antibiotic from Hypericum perforatum L. (in vitro model) part I","authors":"I. Brondz, Anton Brondz","doi":"10.4236/JBPC.2012.34037","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34037","url":null,"abstract":"Today, Hypericum perforatum L. is probably one of the best-characterized medicinal plants, and hyperforin is its best-characterized constituent. Extracts from H. perforatum are widely used as antidepressants; however, less attention has been given to other properties of hyperforin, such as antitumor, fungicidal, antiviral and antibacterial action, or its possible use as a substance with immunomodulation properties. The present study summarizes results that describe the influence of hyperforin as an immunomodulation agent on phagocytosis and the breakdown of Escherichia coli by human polymorphonuclear neutrophils (PMNs). Hyperforin at 1 - 100 μg/mL concentrations was found to have a major influence on phagocytosis and the breakdown of E. coli by PMNs in vitro. A 100 μg/mL solution of hyperforin increased the uptake of non-opsonized E. coli almost 50-fold, and the uptake of IgG-opsonized E. coli more than threefold; on the other hand, the uptake of serum-opsonized bacteria was reduced to approximately 60% of that of the control. Hyperforin seems to bind to both PMNs and E. coli and acts like an opsonin. The elimination of remnants of IgG-opsonized E. coli from the PMNs was stimulated by hyperforin, while the elimination of remnants from non-op-so nized and serum-opsonized material was unaffected by the drug. Hyperforin exhibited clear immunomodulation ability as a phagocytosisstimulating agent. Hyperforin is probably inactive against human immunodeficiency virus (HIV) and most Gram-negative bacteria. However, it can protect acquired immunodeficiency syndrome (AIDS) patients and other immunocompromised patients by its antibacterial activity against Gram-positive bacteria and by enhancement of phagocytosis of Gram-positive and Gram-negative bacteria; some Gram-negative bacteria, such as Neisseria, are sensitive to hyperforin. Hyperforin has the ability to penetrate the blood-brain barrier (BBB) and blood-testis barrier (BTB) and is a valuable antibacterial agent against meningitis and gonorrhea. These properties of hyperforin are important for an antibiotic with immunomodulation activity in the struggle against the growing mortality in AIDS patients as a result of opportunistic bacteria, as recently shown by Bekondi et al. (2006, Int. J. Infect. Dis. 10, 387-395). It could also help to combat primary and opportunistic pathogens associated with meningitis in adults' relation to HIV serostatus.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"More precise model of α-helix and transmembrane α-helical peptide backbone structure","authors":"W. Schmidt, Clayton Thomas","doi":"10.4236/JBPC.2012.34036","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34036","url":null,"abstract":"The 3-D structure of the β-adrenergic receptor with a molecular weight of 55,000 daltons is available from crystallographic data. Within one of the seven transmembrane ion channel helices in the β2-receptor, one loop of a helix ACADL has previously been proposed as the site that explains β2 activity (fights acute bronchitis) whereas ASADL in the β1-receptor at the corresponding site explains β1-activity (cardiac stimulation). The α-agonist responsible for this selective reaction is only 0.5% of the receptor molecular weight, and only 1.5% of the weight of the trans-membrane portion of the receptor. The understanding of the mechanism by which a small molecule on binding to a site on one single loop of a helix produces a specific agonist activity on an entire transmembrane ion channel is uncertain. A model of an α-helix is presented in which of pitch occurs at angles both smaller and larger than 180° n. Consequently, atomic coordinates in a peptide backbone α-helix match the data points of individual atom (and atom types) in the backbone. More precisely, eleven atoms in peptide backbone routinely equal one loop of a helix, instead of eleven amino acid residues equaling three loops of a helix; therefore, an α-helix can begin (or end) at any specific atom in a peptide backbone, not just at any specific amino acid. Wavefront Topology System and Finite Element Methods calculate this specific helical shape based only upon circumference, pitch, and phase. Only external forces which specifically affect circumference, pitch and/or phase (e.g. from agonist binding) can/will alter the shape of an α-helix.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"26S proteasome inhibitors inhibit dexamethasone-dependent increase of tyrosine aminotransferase and tryptophan 2,3-dioxygenase mRNA levels in primary cultured rat hepatocytes","authors":"M. Harashima, M. Hyuga, Y. Nagaoka, C. Saito, M. Furukawa, T. Seki, T. Ariga, N. Kawasaki, S. Niimi","doi":"10.4236/JBPC.2012.34043","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34043","url":null,"abstract":"Dexamethasone (Dex), a ligand for transcriptional enhancement of tyrosine aminotransferase (TAT) and tryptophan 2,3-dioxygenase (TO) genes, (100 nM) maximally increased these mRNA levels at 12 h and 7 h in primary cultured rat hepatocytes and the nuclear fraction, respectively. Lactacystin (5 μM) and epoxomicin (0.5 μM), 26S proteasome inhibitors, significantly suppressed the Dex-dependent maximum increase of TAT and TO mRNA levels in the cells and the nuclear fraction. Electrophoretic mobility shift assay demonstrated that lactacystin did not affect binding of glucocorticoid receptor to glucocorticoid responsive element. Furthermore, lactacystin did not affect the activation of GRE luciferase reporter by Dex transfected to the cells. The results demonstrate that 26S proteasome is positively involved in the Dex-dependent increase of TAT and TO mRNA levels in the cells and suggest that the mechanism of action of 26S proteasome may be degradation of some RNase(s), which breaks down TAT and TO mRNAs.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity of color phenotypes in the koi (Cyprinus carpio L.) as identified by molecular markers","authors":"Bercovich Dani, K. Sigal, Shauder Lior, Degani Gad","doi":"10.4236/JBPC.2012.33029","DOIUrl":"https://doi.org/10.4236/JBPC.2012.33029","url":null,"abstract":"The common carp (Cyprinus carpio) has a large variety of strains. The more popular are the koi (Japanese ornamental carp), which are still bred today to generate creative colors and patterns, giving rise to multiple phenotypes. Since koi are in great demand, there is a challenge to determine the genetics defining their quality. Two methods: 1) direct sequencing of five candidate gene regions, i.e., mitochondrial (cytochrome b, 12S gene and the D-loop) and nuclear (red sensitive opsin and Rag-1) loci, to detect single nucleotide polymorphisms (SNP)s and 2) random amplification of polymorphic DNA (RAPD), were used to differentiate among four koi strains (Kohaku, Sanke, Ghost and Ohgon) and the common carp. Novel SNPs, distinguishing between koi and the common carp, were revealed in cytochrome b, the D-loop and in the red sensitive opsin; one was a missense mutation in cytochrome b at position 15860, in which threonine in the common carp became alanine in all koi strains examined. The Kohaku strain was found to have two alleles in the mitochondrial fragments, forming two different haplotypes (subpo-pulations). These novel SNPs distinguished between koi strains and the common carp, and the RAPD method enabled further differentiation among the four koi strains.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative measurement of p53-p53 antibody interactions by quartz crystal microbalance: A modelsystem for immunochemical calibration","authors":"D. Atha, V. Reipa","doi":"10.4236/JBPC.2012.33024","DOIUrl":"https://doi.org/10.4236/JBPC.2012.33024","url":null,"abstract":"We are developing methods to quantify antibody interactions that include a quartz crystal microbalance (QCM) system to measure, on a molecular basis, the interaction of p53 and anti-p53 antibodies. Previously, as a model system, we developed a measurement device consisting of p53 protein (human wild type), characterized by mass spectroscopy and immobilized at various concentrations on a glass slide. The device is designed as a control to be used with immunohistochemical (IHC) assays that incorporate commercially available anti-p53 antibodies and probes. In the current study, p53 protein is covalently immobilized on a silicon dioxide-coated quartz crystal and the resonance frequency shift is followed in-situ. The functionalized sensor is then incubated with the anti-p53 antibody, which provides a direct gravimetric measure of the antibody-antigen binding. This previously described method allows the comparison of the surface immobilized protein concentrations with estimates obtained by fluorescence measurement. The p53 functionalized QCM system offers an independent measure of surface immobilized protein concentration and is essential in development of our IHC calibration prototypes. These results provide a benchmark for comparing antibody systems that may be used in developing other molecular diagnostic assays such as immunocytochemical analysis and the detection of biomarker proteins in blood and urine.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Visualization of decreased docosahexaenoic acid in the hippocampus of rats fed an n – 3 fatty acid-deficient diet by imaging mass spectrometry","authors":"S. Taira, M. Hashimoto, Kazunori Saito, O. Shido","doi":"10.4236/JBPC.2012.33025","DOIUrl":"https://doi.org/10.4236/JBPC.2012.33025","url":null,"abstract":"The present study employed an imaging mass spectrometry (IMS) method to evaluate the effect of dietary n – 3 fatty acids on the fatty acid composition in rat brain. Rats were divided into two groups and fed either an n – 3 fatty acid-deficient or adequate diet. We determined the decreased n – 3 fatty acids in the hippocampus of rats fed an n – 3 fatty acid-deficient diet compared to the control. IMS visualization was achieved at a resolution of 100 m in rat brain, and showed decreased docosahexaenoic acid (DHA)-containing phosphatidyl choline (PC) or phosphatidyl ethanolamine (PE) in the hippocampus of rats fed an n – 3 fatty acid-deficient diet.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}