Recently, in our experiments, we used the short-circuit current technique to study the kinetic constants for nutrient transporters in rat gastric-intestinal tract and the thickness of the intestinal unstirred layer near the mucosa surface. It was shown that, during the process of aging, the number of nutrient monomer transporters in the small intestine increases twofold, whereas the affinity of transporters to the correspondent nutrients remains unchanged. The situation for peptides may be opposite. The layer thickness in the vicinity of the mucosa surface, measured through glucose, decreased during the process of aging. It was suggested that, in old rats, the role of the digestive volume is more important, which results in an increase of the number of nutrient monomer transporters.
{"title":"Rat small intestine absorption and membrane digestion in the process of aging","authors":"S. T. Metelsky","doi":"10.4236/JBPC.2013.42009","DOIUrl":"https://doi.org/10.4236/JBPC.2013.42009","url":null,"abstract":"Recently, \u0000in our experiments, we used the short-circuit \u0000current technique to study the kinetic constants for nutrient \u0000transporters in rat gastric-intestinal tract and the thickness of the intestinal \u0000unstirred layer near the mucosa surface. It was shown that, during the process of aging, the number of nutrient monomer transporters in the small intestine \u0000increases twofold, whereas the affinity of transporters to the correspondent \u0000nutrients remains unchanged. The situation for peptides may be opposite. The \u0000layer thickness in the vicinity of the mucosa surface, measured through \u0000glucose, decreased during the process of aging. It was suggested that, in old \u0000rats, the role of the digestive volume is more important, which results in an increase of the number of nutrient monomer transporters.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"2013 1","pages":"66-71"},"PeriodicalIF":0.0,"publicationDate":"2013-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902362","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}
A combination of spectral and chromatographic analytical methods has been executed to monitor chemicals in the hair of Vietnamese people. Methods were developed for the determination of some chemical elements in hair by inductively coupled-plasma atomic emission spectroscopy with limits of detection reaching 1 - 100 μg·l－1. A supercritical fluid extraction (SFE) and clean-up procedures were established for isolating organochlorine pollutants (OCPs) and organophosphorus pesticides (OPPs) from the hair of the Vietnamese test subjects. Eight OCPs and OPPs were determined by SFE with carbon dioxide only and methanol-modified carbon dioxide extraction at 350 bar and 45℃, followed by gas chromatography coupled to mass spectrometry. The results indicated that OCPs can be extracted quantitatively using CO2 only, whereas OPPs require a modifier for extraction. The limits of detection that were found were between 0.7 to 1.3 μg·g－1, and good linearity (r2 > 0.9861) was achieved within the tested ranges. The activities of the N-acetyltransferase (NAT) and the monooxygenases cytochrome P450 (CYP 450) were determined and compared to the acetylation and oxidation phenotypes of healthy Vietnamese test subjects. The variations in the concentration of chemical elements in human hair were shown to be dependent upon the activities of the two-phase metabolic system, on the individual’s gender and the duration of residence within Russia.
{"title":"Biomonitoring of organic and inorganic chemicals in the hair of Vietnamese people via spectral and chromatographic analysis","authors":"L. P. Cuong, L. Thuy, M. Evgenev","doi":"10.4236/JBPC.2013.41001","DOIUrl":"https://doi.org/10.4236/JBPC.2013.41001","url":null,"abstract":"A \u0000combination of spectral and chromatographic analytical methods has been executed \u0000to monitor chemicals in the hair of Vietnamese people. Methods were developed for \u0000the determination of some chemical elements in hair by inductively coupled-plasma \u0000atomic emission spectroscopy with limits of detection reaching 1 - 100 μg·l－1. \u0000A supercritical fluid extraction (SFE) and clean-up procedures were established \u0000for isolating organochlorine pollutants (OCPs) and organophosphorus pesticides (OPPs) \u0000from the hair of the Vietnamese test subjects. Eight OCPs and OPPs were determined \u0000by SFE with carbon dioxide only and methanol-modified carbon dioxide extraction \u0000at 350 bar and 45℃, followed by gas chromatography coupled to mass spectrometry. \u0000The results indicated that OCPs can be extracted quantitatively using CO2 only, whereas OPPs require a modifier for extraction. \u0000The limits of detection that were found were between 0.7 to 1.3 μg·g－1, \u0000and good linearity (r2 > 0.9861) was achieved within the tested ranges. The activities of the N-acetyltransferase (NAT) and the monooxygenases cytochrome P450 (CYP 450) were determined and compared to the acetylation \u0000and oxidation phenotypes of healthy Vietnamese \u0000test subjects. The variations in the \u0000concentration of chemical elements in human hair were shown to be dependent \u0000upon the activities of the two-phase metabolic \u0000system, on the individual’s gender and the duration of residence within \u0000Russia.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"04 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2013-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901882","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}
Amy L Stockert, Tarek M Mahfouz, B. Petersen, Oluwaseun L. Fakunmoju
Here we present a docking model that ranks compounds according to their potential effectiveness as a potential substrate or inhibitor. We utilize xanthine oxidase (XO), a multi-cofactor oxido-reductase which converts hypoxanthine to xanthine and xanthine to uric acid. During the reductive half reaction, electrons flow from the molybdopterin, to each of two Fe/S centers, and finally to FAD. During the oxidative half reaction, electrons are passed from the FAD to O2. Under ideal physiological conditions, this reduction of oxygen generates H2O2 and, under multiple turnover conditions, superoxide in amounts which is regulated by catalase and superoxide dismutase. Utilizing computer modeling predictions of the docking orientations and energies of a group of purine based structures was selected. Correlating computer estimations with steady state kinetic data, a rapid screening process for inhibittor prediction was highlighted. This method allows educated selection of likely inhibitors, thereby decreasing the time and supplies required to complete a traditional kinetic analysis screening. Results demonstrate the functionality and reliability of this method and have proven particularly useful in understanding binding orienttations or poses of each compound.
{"title":"Correlation of docking energies with spectroscopic kinetic assays of potential xanthine oxidase substrates","authors":"Amy L Stockert, Tarek M Mahfouz, B. Petersen, Oluwaseun L. Fakunmoju","doi":"10.4236/JBPC.2013.41003","DOIUrl":"https://doi.org/10.4236/JBPC.2013.41003","url":null,"abstract":"Here \u0000we present a docking model that ranks compounds according to their potential \u0000effectiveness as a potential substrate or inhibitor. We utilize xanthine \u0000oxidase (XO), a multi-cofactor oxido-reductase which converts hypoxanthine to \u0000xanthine and xanthine to uric acid. During the reductive half reaction, electrons \u0000flow from the molybdopterin, to each of two Fe/S centers, and finally to FAD. \u0000During the oxidative half reaction, electrons are passed from the FAD to O2. \u0000Under ideal physiological conditions, this reduction of oxygen generates H2O2 and, under multiple turnover conditions, superoxide in amounts which is \u0000regulated by catalase and superoxide dismutase. Utilizing computer modeling \u0000predictions of the docking orientations and energies of a group of purine based \u0000structures was selected. Correlating computer estimations with steady state kinetic data, a rapid screening process for inhibittor prediction was \u0000highlighted. This method allows educated selection of likely inhibitors, \u0000thereby decreasing the time and supplies required to complete a traditional \u0000kinetic analysis screening. Results demonstrate the functionality and \u0000reliability of this method and have proven particularly useful in understanding \u0000binding orienttations or poses of each compound.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"2013 1","pages":"22-27"},"PeriodicalIF":0.0,"publicationDate":"2013-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901974","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}
H. Osanai, T. Ikehara, S. Miyauchi, K. Shimono, Jun Tamogami, T. Nara, N. Kamo
Isothermal titration calorimetry (ITC) was applied to investigate the interaction of drugs with liposomes. Two types of titration are possible. One type is when the liposome suspension in the cell is titrated by aliquots of drug solution, and the other is when the drug and liposome solutions take the opposite roles. In this paper, we employed the latter type because the disturbance of liposomes may be minimal in this titration type. We derived an equation in which the accumulated heat-flow is expressed as a function of the added lipid concentration. In the derivation, the uniform binding model was used although there may be various binding sites. This equation contains a parameter n, the number of binding sites per lipid molecule. In addition, we derive the relation between the dissociation constant (Kd), partition coefficient (Pm) and n. Binding parameters such as Kd, n, the Gibbs energy change, enthalpy change and entropy change were estimated for ANS (1-anilino-8-naphtarenesulfonate), TPB (tetraphenylborate), amlodipine, nifedipine, amitriptyline, nortriptyline, imipramine, desipramine, propranolol, chlorpromazine, promethazine, miconazole, indomethacin, diclofenac and diflunisal. For some drugs, the enthalpy change was the major binding affinity instead of the classical hydrophobic interaction in which entropy takes the essential role. We proved an approximate rule that for drugs with smaller n (the number of binding sites per lipid molecule), the entropy change contributes more than the enthalpy change.
{"title":"A study of the interaction of drugs with liposomes with isothermal titration calorimetry","authors":"H. Osanai, T. Ikehara, S. Miyauchi, K. Shimono, Jun Tamogami, T. Nara, N. Kamo","doi":"10.4236/JBPC.2013.41002","DOIUrl":"https://doi.org/10.4236/JBPC.2013.41002","url":null,"abstract":"Isothermal titration calorimetry (ITC) was applied to investigate the interaction of drugs with liposomes. Two types of titration are possible. One type is when the liposome suspension in the cell is titrated by aliquots of drug solution, and the other is when the drug and liposome solutions take the opposite roles. In this paper, we employed the latter type because the disturbance of liposomes may be minimal in this titration type. We derived an equation in which the accumulated heat-flow is expressed as a function of the added lipid concentration. In the derivation, the uniform binding model was used although there may be various binding sites. This equation contains a parameter n, the number of binding sites per lipid molecule. In addition, we derive the relation between the dissociation constant (Kd), partition coefficient (Pm) and n. Binding parameters such as Kd, n, the Gibbs energy change, enthalpy change and entropy change were estimated for ANS (1-anilino-8-naphtarenesulfonate), TPB (tetraphenylborate), amlodipine, nifedipine, amitriptyline, nortriptyline, imipramine, desipramine, propranolol, chlorpromazine, promethazine, miconazole, indomethacin, diclofenac and diflunisal. For some drugs, the enthalpy change was the major binding affinity instead of the classical hydrophobic interaction in which entropy takes the essential role. We proved an approximate rule that for drugs with smaller n (the number of binding sites per lipid molecule), the entropy change contributes more than the enthalpy change.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"4 1","pages":"11-21"},"PeriodicalIF":0.0,"publicationDate":"2013-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901948","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}
Xin Zhao, Xiaojun Yang, Yong Shi, Guoxiong Chen, Xin‐rong Li
In plant cells the plasma membrane is a highly elaborated structure that functions as the point of exchange with adjoining cells, cell walls and the external environment. In this study, we investigated the structure and function characteristic of wheat root plasma membrane (PM) as affected by H2O2 and Fe by using fluorescence spectroscopic and attenuated total reflectance infrared (ATR-IR) techniques. The results showed that these oxidant damaged induced an obviously reduced membrane fluidity were observed in the roots PM treated with the 200 μM H2O2, FeSO4, and FeCl3. Computer-aided software analyses of the FTIR spectrum indicated that the content of the α-helices decreased and β-sheet increased in the secondary structures of proteins after exposure to the oxidants of 200 μM H2O2, FeSO4, and FeCl3. The number of P=O and C=C bonds area declined rapidly in the lipids of the membrane under the oxidants stress. These structural alterations might explain the reason of the roots PM instability under most of the abiotic stress.
{"title":"Protein and lipid characterization of wheat roots plasma membrane damaged by Fe and H 2 O 2 using ATR-FTIR method","authors":"Xin Zhao, Xiaojun Yang, Yong Shi, Guoxiong Chen, Xin‐rong Li","doi":"10.4236/JBPC.2013.41004","DOIUrl":"https://doi.org/10.4236/JBPC.2013.41004","url":null,"abstract":"In plant cells the plasma membrane is a highly elaborated structure that functions as the point of exchange with adjoining cells, cell walls and the external environment. In this study, we investigated the structure and function characteristic of wheat root plasma membrane (PM) as affected by H2O2 and Fe by using fluorescence spectroscopic and attenuated total reflectance infrared (ATR-IR) techniques. The results showed that these oxidant damaged induced an obviously reduced membrane fluidity were observed in the roots PM treated with the 200 μM H2O2, FeSO4, and FeCl3. Computer-aided software analyses of the FTIR spectrum indicated that the content of the α-helices decreased and β-sheet increased in the secondary structures of proteins after exposure to the oxidants of 200 μM H2O2, FeSO4, and FeCl3. The number of P=O and C=C bonds area declined rapidly in the lipids of the membrane under the oxidants stress. These structural alterations might explain the reason of the roots PM instability under most of the abiotic stress.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"2013 1","pages":"28-35"},"PeriodicalIF":0.0,"publicationDate":"2013-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4236/JBPC.2013.41004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902009","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}
S. Sallam, Khairi M. Tohami, A. Sallam, L. I. A. Salem, F. A. Mohamed
Hydroxy apatite (HA) is a biocompatible material used as bone-substitute materials in both orthopedics and dentistry due to its excellent osteo-conductive and chemical composition similar to that of the inorganic part of bone in comparison with other implant materials . HA (S1) and Cr loaded hydroxy apatite (S2, S3, S4 and S5) of different chromium concentrations have been prepared. many techniques used to analyze the changes occurred due to the substitution. The XRD (X-ray diffraction) and FTIR (Fourier transform infrared radiation )spectroscopy were used as analytical techniques for the prepared HA and Cr loaded HA. The effect of the heat treatment on structural change of the samples was examined by DTA. It was found that all the samples have the same crystalline structure. The crystallinity of the samples decreased as the chromium ions concentration increase.
{"title":"Synthesis and characterization of hydroxyapatite contain chromium","authors":"S. Sallam, Khairi M. Tohami, A. Sallam, L. I. A. Salem, F. A. Mohamed","doi":"10.4236/JBPC.2012.34033","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34033","url":null,"abstract":"Hydroxy apatite (HA) is a biocompatible material used as bone-substitute materials in both orthopedics and dentistry due to its excellent osteo-conductive and chemical composition similar to that of the inorganic part of bone in comparison with other implant materials . HA (S1) and Cr loaded hydroxy apatite (S2, S3, S4 and S5) of different chromium concentrations have been prepared. many techniques used to analyze the changes occurred due to the substitution. The XRD (X-ray diffraction) and FTIR (Fourier transform infrared radiation )spectroscopy were used as analytical techniques for the prepared HA and Cr loaded HA. The effect of the heat treatment on structural change of the samples was examined by DTA. It was found that all the samples have the same crystalline structure. The crystallinity of the samples decreased as the chromium ions concentration increase.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"03 1","pages":"278-282"},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902294","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}
The human telomere sequence (TTAGGG)4 folds into an unusual conformation possessing three G-tetrads linked by TTA loops. The first loop is a propeller loop while the second and third loops are transverse loops. Using Circular Dichroism (CD) spectroscopy, we have investigated the effect of sequence context on the structures and stabilities of intramolecular G-quadruplexes related to the human telomere sequence by considering all permutations of T and A within the loops. The results indicate that changing only one base in any one loop can have a dramatic effect on the conformation of the quadruplex as well as its melting temperature, Tm. Thus, each sequence studied has a unique CD spectrum and Tm. In general, variants with a modified second loop are the most stable while the wild type sequence is the least stable. The observed difference in CD spectra and melting temperature are discussed in terms of base stacking within the loop and stacking of the loop bases with adjacent G-tetrads.
{"title":"A single base permutation in any loop of a folded intramolecular quadruplex influences its structure and stability","authors":"D. Yadav, R. Sheardy","doi":"10.4236/JBPC.2012.34042","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34042","url":null,"abstract":"The human telomere sequence (TTAGGG)4 folds into an unusual conformation possessing three G-tetrads linked by TTA loops. The first loop is a propeller loop while the second and third loops are transverse loops. Using Circular Dichroism (CD) spectroscopy, we have investigated the effect of sequence context on the structures and stabilities of intramolecular G-quadruplexes related to the human telomere sequence by considering all permutations of T and A within the loops. The results indicate that changing only one base in any one loop can have a dramatic effect on the conformation of the quadruplex as well as its melting temperature, Tm. Thus, each sequence studied has a unique CD spectrum and Tm. In general, variants with a modified second loop are the most stable while the wild type sequence is the least stable. The observed difference in CD spectra and melting temperature are discussed in terms of base stacking within the loop and stacking of the loop bases with adjacent G-tetrads.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"3 1","pages":"341-347"},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902213","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}
Cytochrome P4501A (the CYP1A1 and CYP1A2 enzymes) are regulated through the aryl hydrocarbon receptor (AhR)-dependent signal transduction pathway and are generally known as enzymes which metabolize anthropogenic xenobiotics such as dioxin to carcinogenic and mutagenic compounds. However, recently the facts of CYP1A activation under physiological conditions or under action of non-dioxin-like compounds appear. In the present study we show that genistein, herbimycin A and geldanamycin (the protein-tyrosine kinase inhibitors) affect in vivo to CYP1A1 activity, the CYP1A1 mRNA level and the CYP1A1 protein level. These data provide insight into the role of protein kinases in CYP1A regulation may facilitate the understanding of CYP1A regulation.
{"title":"In vivo effects of genistein, herbimycin a and geldanamycin on rat hepatic cytochrome P4501A","authors":"M. Perepechaeva, A. Grishanova","doi":"10.4236/JBPC.2012.34041","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34041","url":null,"abstract":"Cytochrome P4501A (the CYP1A1 and CYP1A2 enzymes) are regulated through the aryl hydrocarbon receptor (AhR)-dependent signal transduction pathway and are generally known as enzymes which metabolize anthropogenic xenobiotics such as dioxin to carcinogenic and mutagenic compounds. However, recently the facts of CYP1A activation under physiological conditions or under action of non-dioxin-like compounds appear. In the present study we show that genistein, herbimycin A and geldanamycin (the protein-tyrosine kinase inhibitors) affect in vivo to CYP1A1 activity, the CYP1A1 mRNA level and the CYP1A1 protein level. These data provide insight into the role of protein kinases in CYP1A regulation may facilitate the understanding of CYP1A regulation.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"03 1","pages":"334-340"},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902326","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}
S. Murakami, F. Takayama, T. Egashira, Mitsuko Imao, A. Mori
Stress ulceration is single or multiple mucosal defects with/without bleeding from the gastric mucosa during the physiologic stress. Oxidative stress (OS) is a key pathogenic factor in psychogenic stress-induced acute gastric mucosal lesion (AGML). Fermented papaya preparation (FPP) is reported to have oxygen radical scavenging activity and is effective in OS-related diseases. Here, we investigated the protective effects and the mechanism of action of FPP on stress-induced AGML in rats, induced by water immersion restraint stress (WIRS). Exposure of rats to 6-hour WIRS resulted in the appearance of splinter hemorrhages and mucosal lesions in the stomach. WIRS induced significant increase in lipid peroxidation and decrease in superoxide dismutase-like activity in both the plasma and gastric mucosa. WIRS also significantly increased myeloperoxidase activity together with Nuclear factor-kappaB (NF-kB) activation in gastric mucosa. FPP reduced all the above changes. The results suggest that oral administration of FPP provides protection against WIRS-induced acute gastric mucosal lesions through its anti-oxidative and anti-inflammatory properties.
应激性溃疡是指在生理性应激作用下，胃粘膜出现单个或多个粘膜缺损，伴有或不伴有出血。氧化应激(Oxidative stress, OS)是心因性应激引起的急性胃粘膜病变(AGML)的重要致病因素。据报道，发酵木瓜制剂(FPP)具有清除氧自由基的活性，对os相关疾病有效。本研究探讨了FPP对水浸抑制应激(WIRS)大鼠应激性AGML的保护作用及其机制。将大鼠暴露于6小时的WIRS导致胃出现碎片状出血和粘膜病变。WIRS诱导血浆和胃粘膜脂质过氧化显著增加，超氧化物歧化酶样活性显著降低。WIRS还显著增加了胃粘膜髓过氧化物酶活性和核因子κ b (NF-kB)的激活。FPP降低了上述所有变化。结果表明，口服FPP通过其抗氧化和抗炎作用对wirs诱导的急性胃黏膜病变具有保护作用。
{"title":"Protective effect of fermented papaya preparation on stress-induced acute gastric mucosal lesion","authors":"S. Murakami, F. Takayama, T. Egashira, Mitsuko Imao, A. Mori","doi":"10.4236/JBPC.2012.34038","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34038","url":null,"abstract":"Stress ulceration is single or multiple mucosal defects with/without bleeding from the gastric mucosa during the physiologic stress. Oxidative stress (OS) is a key pathogenic factor in psychogenic stress-induced acute gastric mucosal lesion (AGML). Fermented papaya preparation (FPP) is reported to have oxygen radical scavenging activity and is effective in OS-related diseases. Here, we investigated the protective effects and the mechanism of action of FPP on stress-induced AGML in rats, induced by water immersion restraint stress (WIRS). Exposure of rats to 6-hour WIRS resulted in the appearance of splinter hemorrhages and mucosal lesions in the stomach. WIRS induced significant increase in lipid peroxidation and decrease in superoxide dismutase-like activity in both the plasma and gastric mucosa. WIRS also significantly increased myeloperoxidase activity together with Nuclear factor-kappaB (NF-kB) activation in gastric mucosa. FPP reduced all the above changes. The results suggest that oral administration of FPP provides protection against WIRS-induced acute gastric mucosal lesions through its anti-oxidative and anti-inflammatory properties.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"3 1","pages":"311-316"},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70901988","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}
Somasekhar R. Chinnadayyala, M. Santhosh, P. Goswami
The reversible effect of microwave mediated denaturation of protein at low exposure time of 10 s has been demonstrated for the first time. The effect of microwave (2.45 GHz and 900 W) was confirmed in a homo-octameric alcohol oxidase in aqueous solution of pH 7.5. The unfolding events did not transverse through any intermediate states and no subunits of the protein were detached during the process. The refolding of the protein achieved at 4℃ for 24 h had regenerated the native enzyme. This reversible refolding approach excludes any chemical reagent and therefore established as simple technique for protein unfolding-folding studies.
{"title":"Microwave based reversible unfolding and refolding of alcohol oxidase protein probed by fluorescence and circular dichroism spectroscopy","authors":"Somasekhar R. Chinnadayyala, M. Santhosh, P. Goswami","doi":"10.4236/JBPC.2012.34039","DOIUrl":"https://doi.org/10.4236/JBPC.2012.34039","url":null,"abstract":"The reversible effect of microwave mediated denaturation of protein at low exposure time of 10 s has been demonstrated for the first time. The effect of microwave (2.45 GHz and 900 W) was confirmed in a homo-octameric alcohol oxidase in aqueous solution of pH 7.5. The unfolding events did not transverse through any intermediate states and no subunits of the protein were detached during the process. The refolding of the protein achieved at 4℃ for 24 h had regenerated the native enzyme. This reversible refolding approach excludes any chemical reagent and therefore established as simple technique for protein unfolding-folding studies.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":"3 1","pages":"317-323"},"PeriodicalIF":0.0,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902039","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}
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