Two new species of Curcuma, C. sattayasaii A. Chaveerach & R. Sudmoon and C. zedoaroides A. Chaveerach & T. Tanee with rhizomes traditionally used for many decades as cobra-bite antidotes are described and illustrat...Two new species of Curcuma, C. sattayasaii A. Chaveerach & R. Sudmoon and C. zedoaroides A. Chaveerach & T. Tanee with rhizomes traditionally used for many decades as cobra-bite antidotes are described and illustrated. Curcuma sattayasaii is similar to C. longa L., but differs in rhizome horizontally branching on ground; coma bracts pinkish-white or pinkish-pale green; corolla pale yellow with orange tip; labellum pale orange with an orange central band; anther crest very short, broadly ovate, wider than long. Curcuma zedoaroides is similar to C. zedoaria (Christm.) Roscoe, but differs in rhizome branching pattern; the protruding secondary rhizomes curved down; blades oblong to oblong-lanceolate; peduncle glabrous; fertile and coma bracts glabrous; corolla lobes pale yellow to white, lateral lobe ovate, dorsal lobe broadly ovate. The new taxa have been found in a village of Khon Kaen Province, Northeastern Thailand.展开更多
The present work was initiated for searching and evaluating the total heavy metal content in some selected local resources used by traditional healers in locally made antidotes to search for their toxicity. Elekat pub...The present work was initiated for searching and evaluating the total heavy metal content in some selected local resources used by traditional healers in locally made antidotes to search for their toxicity. Elekat public slaughterhouse in the city of Bukavu, the central market of Kadutu and in the Ruzizi plain, precisely in Sange city, have been the purchased centers. The samples of bull and cow horns, oil palm nut shells, cow bones, ginger, black pepper and Mwenga salt were used. The spectrometric method has been used to carry out heavy metal content in each local resource using the atomic absorption spectrometer (VARIAN 1275). The heavy metals found and their average content are as follows: copper (Cu: 124.79 mg/kg), lead (Pb: 76.41 mg/kg), chromium (Cr: 33.9 mg/kg), zinc (Zn: 190.86 mg/kg), Arsenic (As: 107.41 mg/kg) and cadmium (Cd: 0.05 mg/kg). The averages of total heavy metal contents for all samples are below the standard of each one. The determination of the heavy metal contents in these samples allows evaluating human intoxication risk. These results show that antidote technology can be run without any toxicity risk and showed statistically significant differences compared to the controls (p 0.05) for chromium, zinc and cadmium have been recorded. However, most of the heavy metals molecules being thioloprives and then bioccumulatives, antidotes made from them shall not be consumed during a long period.展开更多
Chemotherapy extravasation remains an accidental complication of chemotherapy administration and may result in serious damage to patients. We review in this article the clinical aspects of chemotherapy extravasation a...Chemotherapy extravasation remains an accidental complication of chemotherapy administration and may result in serious damage to patients. We review in this article the clinical aspects of chemotherapy extravasation and latest advances in definitions, classification, pre-vention, management and guidelines. We review the grading of extravasation and tissue damage according to various chemotherapeutic drugs and present an update on treatment and new antidotes including dexrazoxane for anthracyclines extravasation. We highlight the importance of education and training of the oncology team for prevention and prompt pharmacological and non-pharmacological management and stress the availability of new antidotes like dexrazoxane wherever anthracyclines are being infused.展开更多
We study a proposed model describing the propagation of computer virus in the network with antidote in vulnerable system. Mathematical analysis shows that dynamics of the spread of computer viruses is determined by th...We study a proposed model describing the propagation of computer virus in the network with antidote in vulnerable system. Mathematical analysis shows that dynamics of the spread of computer viruses is determined by the threshold Ro. If Ro 〈 1, the virusfree equilibrium is globally asymptotically stable, and if R0 〉 1, the endemic equilibrium is globally asymptotically stable. Lyapunov functional method as well as geometric approach are used for proving the global stability of equilibria. A numerical investigation is carried out to confirm the analytical results. Through parameter analysis, some effective strategies for eliminating viruses are suggested.展开更多
Cardio-oncology is a discipline based on early screening,monitoring,and treating chemotherapy-induced cardiotoxicity.There are many chemotherapeutics known for their cardiac toxic effects,including fluoropyrimidines.F...Cardio-oncology is a discipline based on early screening,monitoring,and treating chemotherapy-induced cardiotoxicity.There are many chemotherapeutics known for their cardiac toxic effects,including fluoropyrimidines.Fluoropyrimidine represents the cornerstone of many types of cancer and each year almost two million cancer patients undergo this treatment.Fluoropyrimidine-induced cardiotoxicity can be manifested in several forms,from angina pectoris to sudden death.This paper is a review of how the cardiotoxicity of fluoropyrimidines is presented,the mechanisms of its occurrence,its diagnosis,and management.展开更多
This paper reviews milestones in antidotal therapies for cyanide(CN) spanning early remedies,current antidotal systems and research towards next generation therapies.CN has been a part of plant defense mechanisms for ...This paper reviews milestones in antidotal therapies for cyanide(CN) spanning early remedies,current antidotal systems and research towards next generation therapies.CN has been a part of plant defense mechanisms for millions of years.It became industrially important in the nineteenth century with the advent of CN assisted gold mining and the use of CN as a pest control agent.The biochemical basis of CN poisoning was actively studied and key mechanisms were understood as early as 1929.These fundamental studies led to a variety of antidotes,including indirect CN binders that generate methemoglobin,direct CN binders such as hydroxocobalamin,and sulfur donors that convert CN to the less toxic thiocyanate.Research on blood gases at the end of the twentieth century shed new light on the role of nitric oxide(NO) in the body.The discovery of NO's ability to compete with CN for enzymatic binding sites provided a previously missed explanation for the rapid efficacy of NO generating antidotes such as the nitrites.Presently used CN therapies include:methemoglobin/NO generators(e.g.,sodium nitrite,amyl nitrite,and dimethyl aminophenol),sulfur donors(e.g.,sodium thiosulfate and glutathione),and direct binding agents [(e.g.,hydroxocobalamin and dicobalt salt of ethylenediaminetetraacetic acid(dicobalt edetate)].A strong effort is being made to explore novel antidotal systems and to formulate them for rapid administration at the point of intoxication in mass casualty scenarios.New antidotes,formulations,and delivery systems are enhancing bioavailability and efficacy and hold promise for a new generation of improved CN countermeasures.展开更多
We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL)theory.Compared with the regular square ...We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL)theory.Compared with the regular square array of circular holes,the vortices are no longer pinned inside the circular holes,but instead stabilized at the center of the antidot triplets depending on the geometry parameters.Moreover,the influences of the geometry parameters and the polarity of the applied current on the current–voltage(I–V)characteristics are also studied.The critical current for the sample turning into a normal state becomes smaller when the hole diameter D is smaller and the spacing B between the holes is larger.Due to the asymmetric pinning sites,our numerical simulations demonstrate that the positive and negative rectified voltages appear alternately in the resistive state of the sample under an ac current of square pulses.展开更多
<span style="font-family:Verdana;">A simple method for assessment of the toxicity and antidote effect of selenium nanoparticles with </span><i><i><span style="font-family:Verd...<span style="font-family:Verdana;">A simple method for assessment of the toxicity and antidote effect of selenium nanoparticles with </span><i><i><span style="font-family:Verdana;">Paramecium</span></i><span> <i><span style="font-family:Verdana;">caudatum</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;"> is presented. Light microscopy in combination with computerized video tracking is employed for </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">determination of </span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">survival time of <i></i></span><i><i><span style="font-family:Verdana;">P.</span></i><span> <i><span style="font-family:Verdana;">caudatum</span></i><span style="font-family:Verdana;"></span></span></i></span><span style="font-family:Verdana;">. Up to 800 mg/L, selenium nanoparticles are not acutely toxic. </span><span style="font-family:Verdana;">With</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> respect to a potential antidote effect, the lethality of silver nanoparticles, silver nitrate, sodium hydrogen selenite, and sodium selenite to <i></i></span><i><i><span style="font-family:Verdana;">P.</span></i><span> <i><span style="font-family:Verdana;">caudatum</span></i><span style="font-family:Verdana;"></span></span></i></span><span style="font-family:Verdana;"> was decreased and survival time was extend</span><span style="font-family:Verdana;">ed upon pre-treatment with selenium nanoparticles. Taken together, these findings suggest that administration of selenium nanoparticles attenuates</span><span style="font-family:Verdana;"> exposure </span><span style="font-family:Verdana;">to</span><span style="font-family:Verdana;"> toxicants. Selenium nanoparticles could be a good functional additive for food management in animals.</span>展开更多
The 18 crude drugs in Bofutsushosan (BOF: Pulvis ledebouriellae compositae: 防風通聖散) are separated into 6 groups such as diaphoretic, cathartic, antidote, antipyretic, neutralizer and diuretic groups. The effects o...The 18 crude drugs in Bofutsushosan (BOF: Pulvis ledebouriellae compositae: 防風通聖散) are separated into 6 groups such as diaphoretic, cathartic, antidote, antipyretic, neutralizer and diuretic groups. The effects of single administered BOF and composed crude drugs in 6 groups were investigated on the levels of diabetic parameters (serum glucose, insulin, triglyceride and cholesterol) in streptozotocin-induced diabetic mice. The anti-hyperglycemic action of BOF was depended on Ephedrae Herba, Saposhnikoviae Radix and Schizonepetae Spica in diaphoretic group, Forsythiae Fructus, Saposhnikoviae Radix, Schizonepetae Spica and Cnidii Rhizoma in antidote group, Scutellariae Radix, Gardeniae Fructus and Gypsum Fibrosum in antipyretic group and Paeoniae Radix in neutralizer group. In these crude drugs, Ephedrae Herba, Saposhnikoviae Radix, Schizonepetae Spica, Forsythiae Fructus, Scutellariae Radix, Gypsum Fibrosum and Paeoniae Radix increased serum insulin level, but Cnidii Rhizoma and Gardeniae Fructus did not affect serum insulin level. From these results, it suggested that anti-hyperglycemic action of BOF was through insulin-dependent and insulin independent manners. The lowering effect of BOF on serum triglyceride level was dependent on actions of Platycodi Radix in antidote and diuretic groups and Gardeniae Fructus in antipyretic group. The lowering effect of Gardeniae Fructus was parallel with its anti-hyperglycemic action. The lowering effect of BOF on high serum triglyceride level also included both direct action and indirect action. The reducing effect of BOF on serum cholesterol level was observed together with the actions of Ephedrae Herba and Zingiberis Rhizoma in diaphoretic group, Schizonepetae Spica in diaphoretic and antidote groups and Paeoniae Radix in neutralizer group. The lowering effects of Ephedrae Herba, Schizonepetae Spica and Paeoniae Radix on serum cholesterol level were parallel with their anti-hyperglycemic actions. Zingiberis Rhizoma in diaphoretic group might be direct reducing effect on serum cholesterol level but no serum glucose level. The Ephedrae Herba in diaphoretic group, Schizonepetae Spica in diaphoretic and antidote groups and Paeoniae Radix in neutralizer group might have reduced serum cholesterol level by reducing blood glucose level. From these results, composed crude drugs in 6 groups show various mechanisms in the action of BOF.展开更多
Curcumin(CUR), the main phenolic composition in turmeric, shows preventive effects in various diseases. CUR is commonly found in the Curcuma species and historically applied in herbal medicine. Numerous studies have i...Curcumin(CUR), the main phenolic composition in turmeric, shows preventive effects in various diseases. CUR is commonly found in the Curcuma species and historically applied in herbal medicine. Numerous studies have indicated that CUR possesses protective effects against toxic agents in the various animal tissues including the brain. This study found that CUR may be effective in nervous system problems induced by neurotoxic agents. However, due to the lack of information on human, more investigations are needed to determine the efficacy of CUR as an antidote matter. The current study aimed to critically review the recent literature data from 2014 to 2016 that regarding the therapeutic aspects of CUR versus neurotoxic agents-induced brain damage and its involved mechanisms.展开更多
Ferromagnetic resonance is introduced to examine the microwave frequency response of Ni Fe/Ir Mn bilayers, patterned as antidot arrays. In the experiment, field direction dependence on mode is obtained by rotating the...Ferromagnetic resonance is introduced to examine the microwave frequency response of Ni Fe/Ir Mn bilayers, patterned as antidot arrays. In the experiment, field direction dependence on mode is obtained by rotating the applied magnetic field. We find that at a given resonance frequency, the dependence of the resonance field on the angle has a tendency of sinusoid/cosine variation in the experiment. From micromagnetic simulation it can be seen that spin waves are localized between dots from a given mode profile. This is caused by a demagnetization distribution with a larger value in the center of the two nearest dots than that of the next-nearest dots.展开更多
Magnetoresistance in superconducting Nb films perforated with rectangular arrays of antidots (holes) is investigated at various temperatures and currents. Normally, the magnetoresistance increases with the increasin...Magnetoresistance in superconducting Nb films perforated with rectangular arrays of antidots (holes) is investigated at various temperatures and currents. Normally, the magnetoresistance increases with the increasing magnetic field. In this paper, we report a reverse behavior in a certain range of high fields after vortex reconfiguration transition, where the resistances at non-matching fields are smaller than those in the low field regime. This phenomenon is due to a strong caging effect, in which the interstitial vortices are trapped among the pinned multiquanta vortices. This effect is temperature and current dependent.展开更多
The Zimbabwean financial sector has been retrogressive,constrained,and unpredictable since the year 2000,serving for the multiple currency periods(2009-2013)after the demonetization of the domestic dollar.The sector s...The Zimbabwean financial sector has been retrogressive,constrained,and unpredictable since the year 2000,serving for the multiple currency periods(2009-2013)after the demonetization of the domestic dollar.The sector since then has seen a number of commercial banks fail to meet RBZ(Reserve Bank of Zimbabwe)minimum capital requirements,put under curatorship,delisted or liquidated because of a myriad of operational and financial challenges.The objective of this study is to make an assessment of whether or not the introduction of bond notes has been a curse or blessing.The study drew raw data from bank account holders,academics,general public,corporate world and commercial banks in Masvingo for analysis and interpretation.The study established that the majority of people,corporate world and commercial banks were sceptical to embrace the surrogate bond notes because of the uncertainties,operational and financial risks that they paused on the domestic financial markets.It was also discovered that most banks were quick to pay clients’withdrawals in bond notes,deduct US dollar equivalences from their accounts,and distinguish bond notes from US dollars at the point of making deposits and foreign business transactions.It was also realized that there was market indiscipline and trading in bigger US dollar notes in the informal sector and serious shortage of the same notes in the formal sector.The study concluded that the introduction of bond notes to trade parallel to the US dollar brought a serious shortage of cash on formal markets and increases in the general price level of goods and services.The study therefore recommends that the RBZ should completely withdraw the bond notes from the market to accord the US dollar its world market value and restore confidence and discipline in the Zimbabwean financial sector.The study also recommends another option of the adoption of the South African Rand as an interventionist way of solving Zimbabwe’s liquidity crises.展开更多
Supramolecular systems feature dynamic,reversible and stimuli-responsive characteristics,which are not easily achieved by molecular entities.The last decade has witnessed tremendous advances in the investigations of s...Supramolecular systems feature dynamic,reversible and stimuli-responsive characteristics,which are not easily achieved by molecular entities.The last decade has witnessed tremendous advances in the investigations of supramolecular systems for various bioapplications,which include drug delivery,anticancer therapy,antibacterial therapy,photodynamic therapy,photothermal therapy,combination therapy,antidotes for residual drugs or toxins,and bioimaging and biosensing.Host-guest chemistry has played a key role in the development of such bioactive supramolecular systems,and natural macrocycles(such as cyclodextrins),synthetic macrocycles(such as calixarenes,cucurbit[n]urils,and pillararenes),and porous framework polymers(such as supramolecular organic frameworks and flexible organic frameworks)have been most successfully used as hosts to build different kinds of host-guest systems for attaining designed biofunctions.The self-assembly of rationally designed amphiphilic molecules,macromolecules and polymers represent another important approach for the construction of supramolecular architectures with advanced biofunctions.In this review,we summarize the important contributions made by Chinese researchers in this field,with emphasis on those reported in the past five years.展开更多
Ricin is a highly toxic type 2 ribosome-inactivating protein(RIP)which is extracted from the seeds of castor beans.Ricin is considered a potential bioterror agent and no effective antidote for ricin exists so far.In t...Ricin is a highly toxic type 2 ribosome-inactivating protein(RIP)which is extracted from the seeds of castor beans.Ricin is considered a potential bioterror agent and no effective antidote for ricin exists so far.In this study,by structural modification of a retrograde transport blocker Retro-2cyc1,a series of novel compounds were obtained.The primary screen revealed that compound 27 has an improved antiricin activity compare to positive control.In vitro pre-exposure evaluation in Madin-Darby Canine Kidney(MDCK)cells demonstrated that 27 is a powerful anti-ricin compound with an EC50 of 41.05 nmol/L against one LC(lethal concentration,5.56 ng/mL)of ricin.Further studies surprisingly indicated that 27 confers post-exposure activity against ricin intoxication.An in vivo study showed that 1 h post-exposure administration of 27 can improve the survival rate as well as delay the death of ricin-intoxicated mice.A drug combination of 27 with monoclonal antibody mAb4 C13 rescued mice from one LD(lethal dose)ricin challenge and the survival rate of tested animals is 100%.These results represent,for the first time,indication that small molecule retrograde transport blocker confers both in vitro and in vivo post-exposure protection against ricin and therefore provides a promising candidate for the development of anti-ricin medicines.展开更多
We have developed a π-orbital tight-binding Hamiltonian model taking into account the nearest neighbors to study the effect of antidot lattices(two dimensional honeycomb lattice of atoms including holes) on the band ...We have developed a π-orbital tight-binding Hamiltonian model taking into account the nearest neighbors to study the effect of antidot lattices(two dimensional honeycomb lattice of atoms including holes) on the band structure of silicene and silicon carbide(SiC) sheets. We obtained that the band structure of the silicene antidot superlattice strongly depends on the size of embedded holes, and the band gap of the silicene antidot lattice increases by increasing of holes diameter. The band gap of SiC antidot lattice, except for the lattice of the small unit cell, is independent of the holes diameter and also depends on the distance between holes. We obtained that, the band gap of the SiC antidot lattice is the same as the band gap of the corresponding sheet without hole. Also, the electronic properties of the SiC antidot superlattice occupied either by carbon or by silicon atoms are investigated,numerically. Furthermore, we study the effect of occupation of graphene antidot by Si atoms and vice versa. Also,we have calculated the band structure of graphene and silicene antidot lattice filled by Si + C atoms. Finally, we compute the band structure of the SiC antidot lattice including the holes which are filled by C or by Si atoms.Really, in this paper we have generalized the method of paperabout graphene antidot with empty holes to the cases of filled holes by different atoms and also to the case of silicene and silicon carbide antidot lattices.展开更多
In this work, Co 2D antidot arrays with well-ordered hexagonal holes ranging in size from 1.3 to 6.2 μm were fabricated by colloidal crystal template method. The geometry configuration and magnetic properties of the ...In this work, Co 2D antidot arrays with well-ordered hexagonal holes ranging in size from 1.3 to 6.2 μm were fabricated by colloidal crystal template method. The geometry configuration and magnetic properties of the samples were investigated. An enormous increase in coercivity and squareness, as compared with the corresponding continuous film, was observed. Magnetic properties of Co 2D antidot arrays showed a close dependence on pore diameter. According to geometric calculation, the effect of the pore diameter on magnetic properties was also discussed. The Co 2D antidot arrays obtained by this method are promising candidates for high-density information storage.展开更多
We present a theoretical study of new nanostructures based on bilayered graphene with periodically arranged hexagonal holes (bilayered graphene antidots). Our ab initio calculations show that fabrication of hexagona...We present a theoretical study of new nanostructures based on bilayered graphene with periodically arranged hexagonal holes (bilayered graphene antidots). Our ab initio calculations show that fabrication of hexagonal holes in bigraphene leads to connection of the neighboring edges of the two graphene layers with formation of a hollow carbon nanostructure sheet which displays a wide range of electronic properties (from semiconductor to metallic), depending on the size of the holes and the distance between them. The results were additionally supported by wave packet dynamical transport calculations based on the numerical solution of the time-dependent Schr/Sdinger equation.展开更多
文摘Two new species of Curcuma, C. sattayasaii A. Chaveerach & R. Sudmoon and C. zedoaroides A. Chaveerach & T. Tanee with rhizomes traditionally used for many decades as cobra-bite antidotes are described and illustrated. Curcuma sattayasaii is similar to C. longa L., but differs in rhizome horizontally branching on ground; coma bracts pinkish-white or pinkish-pale green; corolla pale yellow with orange tip; labellum pale orange with an orange central band; anther crest very short, broadly ovate, wider than long. Curcuma zedoaroides is similar to C. zedoaria (Christm.) Roscoe, but differs in rhizome branching pattern; the protruding secondary rhizomes curved down; blades oblong to oblong-lanceolate; peduncle glabrous; fertile and coma bracts glabrous; corolla lobes pale yellow to white, lateral lobe ovate, dorsal lobe broadly ovate. The new taxa have been found in a village of Khon Kaen Province, Northeastern Thailand.
文摘The present work was initiated for searching and evaluating the total heavy metal content in some selected local resources used by traditional healers in locally made antidotes to search for their toxicity. Elekat public slaughterhouse in the city of Bukavu, the central market of Kadutu and in the Ruzizi plain, precisely in Sange city, have been the purchased centers. The samples of bull and cow horns, oil palm nut shells, cow bones, ginger, black pepper and Mwenga salt were used. The spectrometric method has been used to carry out heavy metal content in each local resource using the atomic absorption spectrometer (VARIAN 1275). The heavy metals found and their average content are as follows: copper (Cu: 124.79 mg/kg), lead (Pb: 76.41 mg/kg), chromium (Cr: 33.9 mg/kg), zinc (Zn: 190.86 mg/kg), Arsenic (As: 107.41 mg/kg) and cadmium (Cd: 0.05 mg/kg). The averages of total heavy metal contents for all samples are below the standard of each one. The determination of the heavy metal contents in these samples allows evaluating human intoxication risk. These results show that antidote technology can be run without any toxicity risk and showed statistically significant differences compared to the controls (p 0.05) for chromium, zinc and cadmium have been recorded. However, most of the heavy metals molecules being thioloprives and then bioccumulatives, antidotes made from them shall not be consumed during a long period.
文摘Chemotherapy extravasation remains an accidental complication of chemotherapy administration and may result in serious damage to patients. We review in this article the clinical aspects of chemotherapy extravasation and latest advances in definitions, classification, pre-vention, management and guidelines. We review the grading of extravasation and tissue damage according to various chemotherapeutic drugs and present an update on treatment and new antidotes including dexrazoxane for anthracyclines extravasation. We highlight the importance of education and training of the oncology team for prevention and prompt pharmacological and non-pharmacological management and stress the availability of new antidotes like dexrazoxane wherever anthracyclines are being infused.
文摘We study a proposed model describing the propagation of computer virus in the network with antidote in vulnerable system. Mathematical analysis shows that dynamics of the spread of computer viruses is determined by the threshold Ro. If Ro 〈 1, the virusfree equilibrium is globally asymptotically stable, and if R0 〉 1, the endemic equilibrium is globally asymptotically stable. Lyapunov functional method as well as geometric approach are used for proving the global stability of equilibria. A numerical investigation is carried out to confirm the analytical results. Through parameter analysis, some effective strategies for eliminating viruses are suggested.
文摘Cardio-oncology is a discipline based on early screening,monitoring,and treating chemotherapy-induced cardiotoxicity.There are many chemotherapeutics known for their cardiac toxic effects,including fluoropyrimidines.Fluoropyrimidine represents the cornerstone of many types of cancer and each year almost two million cancer patients undergo this treatment.Fluoropyrimidine-induced cardiotoxicity can be manifested in several forms,from angina pectoris to sudden death.This paper is a review of how the cardiotoxicity of fluoropyrimidines is presented,the mechanisms of its occurrence,its diagnosis,and management.
基金Robert A.Welch Foundation(x-0011)at Sam Houston State University
文摘This paper reviews milestones in antidotal therapies for cyanide(CN) spanning early remedies,current antidotal systems and research towards next generation therapies.CN has been a part of plant defense mechanisms for millions of years.It became industrially important in the nineteenth century with the advent of CN assisted gold mining and the use of CN as a pest control agent.The biochemical basis of CN poisoning was actively studied and key mechanisms were understood as early as 1929.These fundamental studies led to a variety of antidotes,including indirect CN binders that generate methemoglobin,direct CN binders such as hydroxocobalamin,and sulfur donors that convert CN to the less toxic thiocyanate.Research on blood gases at the end of the twentieth century shed new light on the role of nitric oxide(NO) in the body.The discovery of NO's ability to compete with CN for enzymatic binding sites provided a previously missed explanation for the rapid efficacy of NO generating antidotes such as the nitrites.Presently used CN therapies include:methemoglobin/NO generators(e.g.,sodium nitrite,amyl nitrite,and dimethyl aminophenol),sulfur donors(e.g.,sodium thiosulfate and glutathione),and direct binding agents [(e.g.,hydroxocobalamin and dicobalt salt of ethylenediaminetetraacetic acid(dicobalt edetate)].A strong effort is being made to explore novel antidotal systems and to formulate them for rapid administration at the point of intoxication in mass casualty scenarios.New antidotes,formulations,and delivery systems are enhancing bioavailability and efficacy and hold promise for a new generation of improved CN countermeasures.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11702034,11702218,and 11421062)Fundamental Research Funds for the Central Universities,China(Grant Nos.310812171011 and G2016KY0305)the National Key Project of Magneto-Constrained Fusion Energy Development Program,China(Grant No.2013GB110002)
文摘We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL)theory.Compared with the regular square array of circular holes,the vortices are no longer pinned inside the circular holes,but instead stabilized at the center of the antidot triplets depending on the geometry parameters.Moreover,the influences of the geometry parameters and the polarity of the applied current on the current–voltage(I–V)characteristics are also studied.The critical current for the sample turning into a normal state becomes smaller when the hole diameter D is smaller and the spacing B between the holes is larger.Due to the asymmetric pinning sites,our numerical simulations demonstrate that the positive and negative rectified voltages appear alternately in the resistive state of the sample under an ac current of square pulses.
文摘<span style="font-family:Verdana;">A simple method for assessment of the toxicity and antidote effect of selenium nanoparticles with </span><i><i><span style="font-family:Verdana;">Paramecium</span></i><span> <i><span style="font-family:Verdana;">caudatum</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;"> is presented. Light microscopy in combination with computerized video tracking is employed for </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">determination of </span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">survival time of <i></i></span><i><i><span style="font-family:Verdana;">P.</span></i><span> <i><span style="font-family:Verdana;">caudatum</span></i><span style="font-family:Verdana;"></span></span></i></span><span style="font-family:Verdana;">. Up to 800 mg/L, selenium nanoparticles are not acutely toxic. </span><span style="font-family:Verdana;">With</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> respect to a potential antidote effect, the lethality of silver nanoparticles, silver nitrate, sodium hydrogen selenite, and sodium selenite to <i></i></span><i><i><span style="font-family:Verdana;">P.</span></i><span> <i><span style="font-family:Verdana;">caudatum</span></i><span style="font-family:Verdana;"></span></span></i></span><span style="font-family:Verdana;"> was decreased and survival time was extend</span><span style="font-family:Verdana;">ed upon pre-treatment with selenium nanoparticles. Taken together, these findings suggest that administration of selenium nanoparticles attenuates</span><span style="font-family:Verdana;"> exposure </span><span style="font-family:Verdana;">to</span><span style="font-family:Verdana;"> toxicants. Selenium nanoparticles could be a good functional additive for food management in animals.</span>
文摘The 18 crude drugs in Bofutsushosan (BOF: Pulvis ledebouriellae compositae: 防風通聖散) are separated into 6 groups such as diaphoretic, cathartic, antidote, antipyretic, neutralizer and diuretic groups. The effects of single administered BOF and composed crude drugs in 6 groups were investigated on the levels of diabetic parameters (serum glucose, insulin, triglyceride and cholesterol) in streptozotocin-induced diabetic mice. The anti-hyperglycemic action of BOF was depended on Ephedrae Herba, Saposhnikoviae Radix and Schizonepetae Spica in diaphoretic group, Forsythiae Fructus, Saposhnikoviae Radix, Schizonepetae Spica and Cnidii Rhizoma in antidote group, Scutellariae Radix, Gardeniae Fructus and Gypsum Fibrosum in antipyretic group and Paeoniae Radix in neutralizer group. In these crude drugs, Ephedrae Herba, Saposhnikoviae Radix, Schizonepetae Spica, Forsythiae Fructus, Scutellariae Radix, Gypsum Fibrosum and Paeoniae Radix increased serum insulin level, but Cnidii Rhizoma and Gardeniae Fructus did not affect serum insulin level. From these results, it suggested that anti-hyperglycemic action of BOF was through insulin-dependent and insulin independent manners. The lowering effect of BOF on serum triglyceride level was dependent on actions of Platycodi Radix in antidote and diuretic groups and Gardeniae Fructus in antipyretic group. The lowering effect of Gardeniae Fructus was parallel with its anti-hyperglycemic action. The lowering effect of BOF on high serum triglyceride level also included both direct action and indirect action. The reducing effect of BOF on serum cholesterol level was observed together with the actions of Ephedrae Herba and Zingiberis Rhizoma in diaphoretic group, Schizonepetae Spica in diaphoretic and antidote groups and Paeoniae Radix in neutralizer group. The lowering effects of Ephedrae Herba, Schizonepetae Spica and Paeoniae Radix on serum cholesterol level were parallel with their anti-hyperglycemic actions. Zingiberis Rhizoma in diaphoretic group might be direct reducing effect on serum cholesterol level but no serum glucose level. The Ephedrae Herba in diaphoretic group, Schizonepetae Spica in diaphoretic and antidote groups and Paeoniae Radix in neutralizer group might have reduced serum cholesterol level by reducing blood glucose level. From these results, composed crude drugs in 6 groups show various mechanisms in the action of BOF.
文摘Curcumin(CUR), the main phenolic composition in turmeric, shows preventive effects in various diseases. CUR is commonly found in the Curcuma species and historically applied in herbal medicine. Numerous studies have indicated that CUR possesses protective effects against toxic agents in the various animal tissues including the brain. This study found that CUR may be effective in nervous system problems induced by neurotoxic agents. However, due to the lack of information on human, more investigations are needed to determine the efficacy of CUR as an antidote matter. The current study aimed to critically review the recent literature data from 2014 to 2016 that regarding the therapeutic aspects of CUR versus neurotoxic agents-induced brain damage and its involved mechanisms.
基金Project supported by the National Natural Science Foundation of China(Grant No.11304407)the Scientific Research Foundation for Returned Scholars,Ministry of Education of China(Grant No.47)
文摘Ferromagnetic resonance is introduced to examine the microwave frequency response of Ni Fe/Ir Mn bilayers, patterned as antidot arrays. In the experiment, field direction dependence on mode is obtained by rotating the applied magnetic field. We find that at a given resonance frequency, the dependence of the resonance field on the angle has a tendency of sinusoid/cosine variation in the experiment. From micromagnetic simulation it can be seen that spin waves are localized between dots from a given mode profile. This is caused by a demagnetization distribution with a larger value in the center of the two nearest dots than that of the next-nearest dots.
基金Project supported by the National Basic Research Program of China (Grant Nos. 2009CB929100, 2011CBA00107, and 2012CB921302)the National Science Foundation of China (Grant Nos. 10974241 and 11104335)
文摘Magnetoresistance in superconducting Nb films perforated with rectangular arrays of antidots (holes) is investigated at various temperatures and currents. Normally, the magnetoresistance increases with the increasing magnetic field. In this paper, we report a reverse behavior in a certain range of high fields after vortex reconfiguration transition, where the resistances at non-matching fields are smaller than those in the low field regime. This phenomenon is due to a strong caging effect, in which the interstitial vortices are trapped among the pinned multiquanta vortices. This effect is temperature and current dependent.
文摘The Zimbabwean financial sector has been retrogressive,constrained,and unpredictable since the year 2000,serving for the multiple currency periods(2009-2013)after the demonetization of the domestic dollar.The sector since then has seen a number of commercial banks fail to meet RBZ(Reserve Bank of Zimbabwe)minimum capital requirements,put under curatorship,delisted or liquidated because of a myriad of operational and financial challenges.The objective of this study is to make an assessment of whether or not the introduction of bond notes has been a curse or blessing.The study drew raw data from bank account holders,academics,general public,corporate world and commercial banks in Masvingo for analysis and interpretation.The study established that the majority of people,corporate world and commercial banks were sceptical to embrace the surrogate bond notes because of the uncertainties,operational and financial risks that they paused on the domestic financial markets.It was also discovered that most banks were quick to pay clients’withdrawals in bond notes,deduct US dollar equivalences from their accounts,and distinguish bond notes from US dollars at the point of making deposits and foreign business transactions.It was also realized that there was market indiscipline and trading in bigger US dollar notes in the informal sector and serious shortage of the same notes in the formal sector.The study concluded that the introduction of bond notes to trade parallel to the US dollar brought a serious shortage of cash on formal markets and increases in the general price level of goods and services.The study therefore recommends that the RBZ should completely withdraw the bond notes from the market to accord the US dollar its world market value and restore confidence and discipline in the Zimbabwean financial sector.The study also recommends another option of the adoption of the South African Rand as an interventionist way of solving Zimbabwe’s liquidity crises.
文摘Supramolecular systems feature dynamic,reversible and stimuli-responsive characteristics,which are not easily achieved by molecular entities.The last decade has witnessed tremendous advances in the investigations of supramolecular systems for various bioapplications,which include drug delivery,anticancer therapy,antibacterial therapy,photodynamic therapy,photothermal therapy,combination therapy,antidotes for residual drugs or toxins,and bioimaging and biosensing.Host-guest chemistry has played a key role in the development of such bioactive supramolecular systems,and natural macrocycles(such as cyclodextrins),synthetic macrocycles(such as calixarenes,cucurbit[n]urils,and pillararenes),and porous framework polymers(such as supramolecular organic frameworks and flexible organic frameworks)have been most successfully used as hosts to build different kinds of host-guest systems for attaining designed biofunctions.The self-assembly of rationally designed amphiphilic molecules,macromolecules and polymers represent another important approach for the construction of supramolecular architectures with advanced biofunctions.In this review,we summarize the important contributions made by Chinese researchers in this field,with emphasis on those reported in the past five years.
基金the financial supports of the National Science and Technology Major Projects for"Major New Drugs Innovation and Development"(2018ZX09711003-001-001)of China.
文摘Ricin is a highly toxic type 2 ribosome-inactivating protein(RIP)which is extracted from the seeds of castor beans.Ricin is considered a potential bioterror agent and no effective antidote for ricin exists so far.In this study,by structural modification of a retrograde transport blocker Retro-2cyc1,a series of novel compounds were obtained.The primary screen revealed that compound 27 has an improved antiricin activity compare to positive control.In vitro pre-exposure evaluation in Madin-Darby Canine Kidney(MDCK)cells demonstrated that 27 is a powerful anti-ricin compound with an EC50 of 41.05 nmol/L against one LC(lethal concentration,5.56 ng/mL)of ricin.Further studies surprisingly indicated that 27 confers post-exposure activity against ricin intoxication.An in vivo study showed that 1 h post-exposure administration of 27 can improve the survival rate as well as delay the death of ricin-intoxicated mice.A drug combination of 27 with monoclonal antibody mAb4 C13 rescued mice from one LD(lethal dose)ricin challenge and the survival rate of tested animals is 100%.These results represent,for the first time,indication that small molecule retrograde transport blocker confers both in vitro and in vivo post-exposure protection against ricin and therefore provides a promising candidate for the development of anti-ricin medicines.
文摘We have developed a π-orbital tight-binding Hamiltonian model taking into account the nearest neighbors to study the effect of antidot lattices(two dimensional honeycomb lattice of atoms including holes) on the band structure of silicene and silicon carbide(SiC) sheets. We obtained that the band structure of the silicene antidot superlattice strongly depends on the size of embedded holes, and the band gap of the silicene antidot lattice increases by increasing of holes diameter. The band gap of SiC antidot lattice, except for the lattice of the small unit cell, is independent of the holes diameter and also depends on the distance between holes. We obtained that, the band gap of the SiC antidot lattice is the same as the band gap of the corresponding sheet without hole. Also, the electronic properties of the SiC antidot superlattice occupied either by carbon or by silicon atoms are investigated,numerically. Furthermore, we study the effect of occupation of graphene antidot by Si atoms and vice versa. Also,we have calculated the band structure of graphene and silicene antidot lattice filled by Si + C atoms. Finally, we compute the band structure of the SiC antidot lattice including the holes which are filled by C or by Si atoms.Really, in this paper we have generalized the method of paperabout graphene antidot with empty holes to the cases of filled holes by different atoms and also to the case of silicene and silicon carbide antidot lattices.
基金financially supported by the Innovation Foundation of Aviation Industry Corporation of China (No. JK65150307)
文摘In this work, Co 2D antidot arrays with well-ordered hexagonal holes ranging in size from 1.3 to 6.2 μm were fabricated by colloidal crystal template method. The geometry configuration and magnetic properties of the samples were investigated. An enormous increase in coercivity and squareness, as compared with the corresponding continuous film, was observed. Magnetic properties of Co 2D antidot arrays showed a close dependence on pore diameter. According to geometric calculation, the effect of the pore diameter on magnetic properties was also discussed. The Co 2D antidot arrays obtained by this method are promising candidates for high-density information storage.
文摘We present a theoretical study of new nanostructures based on bilayered graphene with periodically arranged hexagonal holes (bilayered graphene antidots). Our ab initio calculations show that fabrication of hexagonal holes in bigraphene leads to connection of the neighboring edges of the two graphene layers with formation of a hollow carbon nanostructure sheet which displays a wide range of electronic properties (from semiconductor to metallic), depending on the size of the holes and the distance between them. The results were additionally supported by wave packet dynamical transport calculations based on the numerical solution of the time-dependent Schr/Sdinger equation.