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Polyacrylonitrile (PAN) nascent fiber plays an important role in the structural formation and development of the precursor fibers and carbon fibers. This work is used to evaluate the effect of dryi...

Flattened and crushed fiber-bundles of moso bamboo (Phyllostachys pubescens) were dyed with a water or alcohol-based dye at 20 °C, 75 °C or 90 °C for 72 h, followed by drying and coating with PF resin. Hot-pressed bamboo fiber composites (BFC) were manufactured, and the weathering performance of the composites made from dyed and natural bamboo material were tested over 90 days of the Autumn/Winter season in Beijing. Dye was able to penetrate the bamboo tissue to create a rich red color that degraded in color faster than BFC made from un-dyed bamboo. BFC made from un-dyed tissue remained a lighter but more consistent color over the weathering period. Dying the bamboo in ethanol-based dye was effective at pigmenting the product, but made it more susceptible to color degradation as well as greater mass and thickness loss due to the chemical degradation of the lignin caused by ethanol. Higher temperature of water dying treatment (90 °C) gave the greatest resistance to mass and thickness loss during outdoor exposure, and the bamboo may have benefitted from the longer period of ‘heat treatment’ during dyeing. Further work is needed to quantify dye leaching from bamboo tissue and to develop more water-tight and color-fast, weather resistant dyes for bamboo products.

The ability to incorporate functional metal ions (Mn+ ) into metal-organic coordination complexes adds remarkable flexibility in the synthesis of multifunctional organic-inorganic hybrid materials with tailorable electronic, optical, and magnetic properties. We report the cation-exchanged synthesis of a diverse range of hollow Mn+ -phytate (PA) micropolyhedra via the use of hollow Co2+ -PA polyhedral networks as templates at room temperature. The attributes of the incoming Mn+ , namely Lewis acidity and ionic radius, control the exchange of the parent Co2+ ions and the degree of morphological deformation of the resulting hollow micropolyhedra. New functions can be obtained for both completely and partially exchanged products, as supported by the observation of Ln3+ (Ln3+ =Tb3+ , Eu3+ , and Sm3+ ) luminescence from as-prepared hollow Ln3+ -PA micropolyhedra after surface modification with dipicolinic acid as an antenna. Moreover, Fe3+ - and Mn2+ -PA polyhedral complexes were employed as magnetic contrast agents.

A novel method of the continuous activation of persulfates will improve the possibility of persulfates entering the actual wastewater. The main purpose of this study was to use a g-C3N4/ZnO catalyst to reduce Fe(III) to activate persulfates, effectively degrade rhodamine B (RhB) under visible light irradiation, and analyze the degradation process and mechanism of RhB. First, the g-C3N4/ZnO catalyst was prepared by a simple calcination method. Second, the photocatalyst was used to generate photoelectrons that reduced Fe(III) to Fe(II) and then, Fe(II) was used to activate the persulfates and release the sulfate radicals. The as-prepared samples were characterized by XPS, EDS, XRD and TEM. The optimal conditions (light intensity, catalyst dosage and anions) were investigated for the degradation of RhB, and the experiments of different pollutants were compared under the same conditions. Finally, RhB was oxidized by hydroxyl radicals and sulfate radicals to make it completely mineralized. During the whole degradation process, the holes and photoelectrons generated by the photocatalyst were involved in the degradation of pollutants in the form of hydroxyl radicals and sulfate radicals, respectively. This not only improves the efficiency of electron and hole separation, but also greatly improves the utilization of light energy, due to which the use of light energy is not limited to a single hole or photoelectron. The theory and method of using photogenerated electrons to obtain Fe(II) to activate persulfates and continuously release sulfate free radicals were proposed, which provided an idea for the application of photocatalytic Fenton-like reactions in practical engineering in the future.

Purpose The purpose of this study was to determine the longitudinal changes in macular retinal and choroidal microvasculature in normal healthy and highly myopic eyes. Methods Seventy-one eyes, including 32 eyes with high myopia and 39 healthy control eyes, followed for at least 12 months and examined using optical coherence tomography angiography imaging in at least 3 visits, were included in this study. Fovea-centered 6 × 6 mm scans were performed to measure capillary density (CD) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC). The rates of CD changes in both groups were estimated using a linear mixed model. Results Over a mean 14-month follow-up period, highly myopic eyes exhibited a faster rate of whole image CD (wiCD) loss (−1.44%/year vs. −0.11%/year, P = 0.001) and CD loss in the outer ring of the DCP (−1.67%/year vs. –0.14%/year, P < 0.001) than healthy eyes. In multivariate regression analysis, baseline axial length (AL) was negatively correlated with the rate of wiCD loss (estimate = −0.27, 95% confidence interval [CI] = −0.48 to −0.06, P = 0.012) and CD loss in the outer ring (estimate = −0.33, 95% CI = −0.56 to −0.11, P = 0.005), of the DCP. The CD reduction rates in the SCP and CC were comparable in both groups (all P values > 0.05). Conclusions The rate of CD loss in the DCP is significantly faster in highly myopic eyes than in healthy eyes and is related to baseline AL. The CD in the outer ring reduces faster in eyes with longer baseline AL.

A novel magnetic borate-functionalized metal-organic framework nanocomposite was designed and fabricated for selective enrichment of catecholamines from human urine. Firstly, the polytannic acid (PTA) layer with natural low-cost and ecofriendly polyphenol tannic acid as the organic ligand and Fe3+ as the cross-linker was coated onto the surface of Fe3O4. Then, the borate-functionalized metal-organic framework (MIL-100(Fe)-B) with 5-boronobenzene-1,3-dicarboxylic acid as a ligand fragment was modified onto the PTA-coated Fe3O4 through a metal-ligand-fragment coassembly strategy. The obtained smart porous adsorbent Fe3O4@PTA@MIL-100(Fe)-B was confirmed by means of several characterization methods and then applied as an effective magnetic solid phase extraction (MSPE) sorbent for specific extraction of trace catecholamines in human urine. The Plackett–Burman design was used for screening the variables significantly affecting the extraction efficiency. Then, the significant factors were further investigated by the Box–Behnken design to determine the optimal extraction conditions. Under the optimal conditions, a method for selective MSPE combined with high-performance liquid chromatography with a fluorescence detector for the quantitation of catecholamines in human urine was developed and validated. With the proposed method, the linearity range was from 0.500 to 500 ng mL−1 for norepinephrine and epinephrine and from 1.00 to 500 ng mL−1 for dopamine. The detection limits were 0.050, 0.11, and 0.20 ng mL−1 for norepinephrine, epinephrine, and dopamine, respectively. The recoveries from spiking experiments varied from 91.5 to 108% with relative standard deviations (RSDs) of 0.80–4.8%. The established method is rapid, sensitive, accurate, inexpensive, and ecofriendly and was successfully applied to the determination of the target catecholamines in human urine samples.

The microfibrils served as the structural elements in polyacrylonitrile (PAN) fiber, which played an important role in the quality of the PAN precursor fibers. Their morphologies were examined by the scanning electron microscopy (SEM), atomic force microscopy (AFM) and high-resolution transmission electron microscope (HRTEM). The microfibrils existed in all of PAN fibers and arranged evenly in the cross-sections. Furthermore, the pores existed between the microfibrils. The unoriented microfibrillar network was already formed in nascent fiber during coagulated process. Although the microfibrillar network was elongated and the microfibrils oriented along the fiber longitudinal direction during the spinning process, the interconnected microfibrillar network was still existed in the fiber transverse section. Furthermore, the transverse connection of the microfibrils was reinforced and the small microfibrils were tended to aggregate into the large fibrils. For mechanical performance of PAN fibers, their tensile strength increased to 708 MPa and the elongation at break decreased to 15.5%. PAN fibers exhibited ductile rupture during the mechanical test and the microfibrils served as reinforcing elements.

The dry-jet wet spinning polyacrylonitrile fibers (PAN fibers) were preoxidized in six gradient-elevated temperature zones and the internal structure changed greatly. Ultrathin sections for electron microscopy were used to study the internal structure of the fibers, and the fibril structure in the fibers was first observed by ultrasonic etching under a high-resolution transmission microscope. The fibers were ultrasonically etched in dimethyl sulfoxide (DMSO) solution to separate the fibril structure. The fibril structure is parallel to the fiber axis and the lamellar-plate structure is arranged perpendicular to the fiber axis.

The ability to reversibly manipulate the surface nature of luminescent nanoparticles upon external stimulation enables the development of advanced optical probes for biological sensing and data encoding. Herein, we report the synthesis of a new class of smart carbon dots (CDs) via surface modification of amine-enriched CDs with CO2-responsive groups of amidine. We present that alternative CO2 and N2 bubbling can not only lead to a reversible phase transfer of the CDs between an organic phase and an aqueous phase but also give rise to a corresponding reversible luminescence change between blue and cyan-green. We attribute these observations to changes in both the surface chemistry and the emission states of the CDs triggered by the alternative CO2/N2 introduction. We also find a similar luminescence change of the CDs upon alternative exposure to a humid vapor of CO2 and a mixture of NH3 and N2 at room temperature, allowing them to be used as a new class of optical materials for optical encoding.

The aim of the study was to investigate the effect of hydroxyl-radical on myofibrillar protein properties. Myofibrillar protein isolated from Alaska pollock muscles were incubated with oxidant agents containing different H2O2 concentrations of 0, 0.1, 1, 5, 10 and 20 mmoL/L for 1, 3 and 5 h respectively. Incubation at higher concentrations of H2O2 induced a significant decrease of protein total sulfhydryl group and an increase in protein carbonyl content in the myofibrillar fraction. Moderate H2O2 concentration (1 mmoL/L) enhanced water-holding capacity and textural properties of a gel, while lower (0.1 mmoL/L) and higher (5, 10 & 20 mmoL/L) H2O2 concentrations significantly reduced the water-holding capacity. At higher H2O2 concentration, oxidized gel revealed some resistance toward the change in gel properties. Additionally, the results from SDS-PAGE and microstructure confirmed the structural changes through aggregation and denaturation of myofibrillar components that induced changes on gelation of myofibrillar protein. The whiteness of the myofibrillar protein gel decreased significantly (p

Over years, various biological constituents are isolated from Traditional Chinese Medicine and confirmed to show multifunctional activities. Magnolol, a hydroxylated biphenyl natural compound isolated fromMagnolia officinalis, has been extensively documented and shows a range of biological activities. Many signaling pathways include, but are not limited to, NF-κB/MAPK, Nrf2/HO-1, and PI3K/Akt pathways, which are implicated in the biological functions mediated by magnolol. Thus, magnolol is considered as a promising therapeutic agent for clinic research. However, the low water solubility, the low bioavailability, and the rapid metabolism of magnolol dramatically limit its clinical application. In this review, we will comprehensively discuss the last five-year progress of the biological activities of magnolol, including anti-inflammatory, antimicroorganism, antioxidative, anticancer, neuroprotective, cardiovascular protection, metabolism regulation, and ion-mediating activity.

The mesopore structures in polyacrylonitrile (PAN) fibers during dry-jet wet spinning process were investigated by high-resolution transmission electron microscopy (HRTEM) and image analysis utilizing the ultrathin section technique. The morphologies and dimension distribution of the mesopores in the surface and core regions of the nascent fibers and PAN fibers are presented. All fibers exhibited lamellar-like structures perpendicular to the fiber axis and the mesopores were distributed between the lamellae. For nascent fibers, the size and volume of the mesopores increased with increasing air gap and decreased with increasing drawing ratio. In addition, the widths of the mesopores were larger than their lengths. Consequently, the size and content of the mesopores in nascent fibers could be adjusted by controlling coagulation conditions. During the post-spinning process, the size and volume of the mesopores in PAN fibers decreased efficiently by hot drawing in a hot water washing bath, in hot steam chambers or on hot rollers. Moreover, the lengths of the mesopores were larger than their widths. In all fiber samples, the number and size of the mesopores in the core region were larger than those in the surface region. In addition, the mechanical properties of fibers were correlated with dimension of the mesopores. Their tensile strength increased with decreasing mesopore widths and lengths.

The development of earth-abundant catalysts for efficient hydrolysis of ammonia borane is of great importance in the conversion and utilization of hydrogen energy. Here, we report the synthesis of SiO2-encompassed Co@N-doped porous carbon assemblies as a new type of recyclable catalyst for the purpose by calcination of zeolitic imidazolate framework-67@SiO2 microtubes at high temperatures under an N2 atmosphere. We find that the surface layer of SiO2 in the precursor microtubes is essential for the production of efficient catalysts by supplying an additional surface for Co nanoparticle dispersion in an effort to reduce their size. In addition, the SiO2 layer renders a highly ordered arrangement of Co@N-doped porous carbon within the catalysts, possibly allowing the ease of mass transfer of ammonia borane within the catalysts. The optimized catalysts obtained via calcination at 800 °C show a set of remarkable catalytic benefits, including a high hydrogen generation rate of 8.4 mol min–1 mol(Co)–1, a relati...

Excellent poly(acrylonitrile-co-itaconic acid) (99/1) (PAI) nascent fibers, which have an important role in preparing high-quality precursors for carbon fibers, were prepared by a dry-jet wet spinn...

Curdlan/β-cyclodextrin (β-CD) composite hydrogels were prepared by using epichlorohydrin (ECH) and ethylene glycol diglycidyl ether (EGDGE) as cross-linkers respectively. The results showed that a ...

Assessing renal function accurately is important for human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) patients. Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) recommended three equations to calculate estimated glomerular filtration rate (eGFR). There is evidence that eGFR based on the combination of serum creatinine and cystatin C is the most accurate of the three equations. But there is limited data on the comparison of three CKD-EPI equations in Chinese HIV/AIDS patients. The aim of our study was to compare the three CKD-EPI equations in Chinese HIV/AIDS population and assess renal function. Cross-sectional, single center, prospective study. One hundred seventy two Chinese adult HIV/AIDS patients were enrolled, including 145 (84.3%) males and 27 (15.7%) females. Mean age was 40(±12) years old. Overall mean eGFR based on serum creatinine, cystatin C and the combination of the 2 markers was 112.6(±19.0) mL/min/1.73 m2, 92.0(±24.2)mL/min/1.73 m2, and 101.7(±21.8)mL/min/1.73 m2, respectively (P = .000). The eGFR calculated by serum creatinine alone is higher than eGFR calculated by combination of serum creatinine and cystatin C, and eGFR calculated by cystatin C individual is lower than eGFR calculated by combination of the 2 markers. Of the 3 CKD-EPI equations, the CKD-EPIscr-cys equation may have the most accuracy in evaluating renal function in Chinese HIV/AIDS patients while the CKD-EPIscr equation may overestimate renal function and the CKD-EPIcys equation may underestimate renal function.

The large yellow croakers (Larimichthys crocea) are mainly present in the Chinese coast and near seas with high economic importance, but vulnerable to many diseases, especially in the breeding and aquaculture. The purpose of this research was to boost the innate immune system of the large yellow croaker by administering bitter peptides into their peritoneal cavity. Total 120 Juvenile of large yellow croakers in very even weight of 60 g were divided into 4 different groups in 200/300 L of water tank, respectively. Fish growth were observed for 3 months before and after different treatments. The bitter peptides from pepsin hydrolysis were applied because they possess the highest bitter sensory scores. The blood of fish from the different groups was collected and tested for different immune parameters to evaluate the effectiveness of bitter peptides as immune stimulants after administration for 8 weeks. The average ratio of leukocytes/total blood cells (%) for control was found at 14.6%, for the low dose of bitter peptides 0.6 mg/fish was at 29.3%, for middle dose of 1.2 mg/fish was at 35%, and high dose of 2.4 mg/fish was at 30%. The lysozyme assay showed that the OD (optical density) units of relative progress lysis activity at 60 min were 0.17, 0.101, 0.307 and 0.198, respectively. Similarly in the same order as in phagocyte assay, most importantly the middle dose (1.2mg/fish) gave the highest survival rate throughout the assay. The results showed that bitter peptides can be used as immune boosters for the yellow croakers and the optimum dose was 1.2 mg/fish due to both leukocytes and lysozyme activity in the treated samples increased significantly compared with the control group. According to the results obtained, we suggest that the incorporation of middle dose of bitter peptides into fish feeds may reduce the fish diseases in aquaculture, at least for large yellow croakers.

In this work, acrylonitrile copolymers were prepared via precipitation polymerization. The copolymer solutions prepared at various ratio of dimethyl sulfoxide and dimethylacetamide were tested to prepare the nascent fibers by one-step wet-spun method. The effect of temperature, solvent ratio, molecular weight and the solid content on the rheological properties of polyacrylonitrile gel solution in different mixed solvent were studied. It was shown that the viscosity decreased with the increase of the temperature and fluctuated with the different solvent ratio reaching the minimal value at the ratio of dimethyl sulfoxide to dimethylacetamide equal to 1.25. The crystallinity of copolymers and the structure of the nascent fiber surface also depended from the solvent ratio in polymerization. The optimum conditions for spinnability of copolymers were determined. The high-quality polyacrylonitrile precursor was achieved with the controllable range of 0.5–0.8 dtex and the toughness of polyacrylonitrile precursor was greater than 6.0 cN/dtex after the wet spinning process, while the tensile strength of carbon fiber is up to 6.25 GPa after their pre-oxidation and carbonization process.

The interior microstructures of polyacrylonitrile nascent fibers is studied by the scanning electronic microscopy and the high-resolution transmission electron microscopy through ultrasonic etching and ultrathin sectioning. Due to the orientation and fold of molecular chains, the lamellae of 50–80 nm in thickness are formed. A high number of pores, ranging from dozens to two hundred nanometers in diameters exist between the lamellae, which result from residual solvent. The fibril structure is formed in the nascent fiber during the coagulation process, which are oriented along the fiber axis. An uneven tensile stress distribution leads to the formation of skin-core structures in the nascent fiber during the dry-jet wet spinning process.

An understanding of the properties of polyacrylonitrile (PAN) precursors is an essential precondition for manufacturing high-performance carbon fibres, and the structure of the precursors has a direct and profound effect on the performance of carbon fibres. In this study, PAN precursors, formed in a multistage coagulation bath, were spun by a dry-jet wet spinning process, and the multi-scale microstructure and morphology of the precursors were investigated by separating the fibrils from the precursors. Scanning electron microscopy and high-resolution transmission electron microscopy were employed to examine the surface morphology, cross-sectional morphology and microstructure of the precursors. X-ray diffraction was used to characterize the crystal structure. The micropore sizes of the precursors were determined with nitrogen adsorption experiments; the adsorption increased after ultrasonic etching and decreased with an increase in the treated concentration. All the results demonstrated that the PAN precursors had a multi-scale microstructure, the precursors consisted of fibrils with diameters of 80–200 nm and the fibrils consisted of some microfibrils with diameters of 20–40 nm, including the periodic tissues with thicknesses of 16–30 nm perpendicular to the fibre axis.

A novel, magnetically separable, and stable Fe3O4/graphitic carbon nitride (g-C3N4) nanocomposites were prepared using a facile method. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectroscopy. The photocatalysis capability and stability of the as-prepared samples were studied by the degradation of rhodamine B (RhB) under simulated sun irradiation. In addition, the degree of mineralization of RhB and the optimum conditions (pH and dosage of catalyst) for the reaction system were investigated. Tetracycline was used to remove the sensitization effect. Fe3O4/g-C3N4 nanocomposites not only had higher photocatalytic activity but also obtained magnetic property and stronger stability, which are important for the reuse in water pollutant treatment. Photoelectrochemical activities of Fe3O4/g-C3N4 were also investigated. The photocurrent enhancement indicates a higher separation efficiency of electrons and holes due to the heterojunction between Fe3O4 and g-C3N4. RhB degradation improved under acidic conditions and simulated sun irradiation, given that more OH is produced because of the oxidation of Fenton. The h+ is a main participant in the degradation of RhB. Active species analysis showed that dissolved oxygen plays an important role in the formation of reactive species ( O2− and OH), which are also important participants in the degradation of RhB.

Nanocrystals (NCs), a type of innovative material particle, are a potential drug delivery platform that aims to improve the bioavailability of hydrophobic drugs. However, due to the lack of consideration of their toxicity, existing studies have not investigated whether the nanoscale properties of NCs, such as particle sizes, may lead to NC-induced toxicity. Because of the disparity between the rapid development of NCs and the lack of studies regarding NC toxicity, the present study investigated possible NC toxicity and clarified the relationship between particle sizes and NC toxicity. RAW264.7 and HepG2 cells were chosen as representatives of macrophage cells and tissue-type cells, respectively. Monosodium urate NCs were used as a drug model. Different particle sizes of monosodium urate NCs were prepared using precipitation methods. Methyl tetrazolium, lactate dehydrogenase, oxidative stress and apoptosis/necrosis assays were then used to evaluate cell damage and recovery. The results showed that small NC particle sizes produced higher toxicity than larger ones. In immune cells, these cytotoxic effects were greater than in tissue cells. After removal of small NCs, tissue cell damage could be significantly reversed, while immune cells were only slightly restored. However, after removal of large NCs, both cell types had almost no recovery. In summary, despite conventional wisdom, our research confirmed that NCs are not very safe and that NC particle sizes are closely related to the degree of NC toxicity.

Modification of cellulose homogeneously by graft copolymerization via grafting-from or grafting-to approaches is an attractive and versatile way to impart specific properties onto this promising renewable material. The grafting efficiency is greatly influenced by the solvent and catalyst used during this process. In this study, cellulose-graft-poly ( l -lactic acid) (C-g-PLLA) was prepared by ring opening polymerization of l -lactide (LA) (grafting-from) and transesterification of PLLA (grafting-to) with cellulose dissolved in CO2 switchable solvent. The impact of the presence of 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU) was then elucidated by comparing the grafting efficiency of the process with or without adding extra amount of this organic superbase. Results showed that without adding extra DBU, the grafting efficiency increased with an increase in concentration of grafting agents (LA or PLLA). However, when extra DBU was added, the grafting efficiency decreased with increased levels of DBU. These results indicate that the DBU protonated by the hydroxyl group from cellulose participated in the dissolution of cellulose after capture of CO2 in the switchable solvent, and played a role in the graft copolymerization to produce C-g-PLLA. On the other hand, the free DBU that was unprotonated displayed an antagonistic effect towards grafting copolymerization. Detailed graft copolymerization pathways and related modes of action were then considered in attempt to provide new insight into the role of CO2 switchable solvent for cellulose modification by ROP or transesterification.

The quaternized curdlan with a high degree of substitution (DS) were synthesized using glycidyl trimethyl ammonium chloride in NaOH aqueous solution by two-step in this work. The structure, property and morphology of curdlan and quaternized curdlan were characterized by 1H NMR, 13C NMR, FTIR, XRD, GPC, TG and ultra-depth three-dimensional microscope. The DS were calculated from the integral area of 1H NMR spectroscopy. The influence of the molar ratio which is between the anhydroglucose unit (AGU) and the quaternized reagent (QR), and reaction time on the DS were studied. The quaternized curdlan with different DS had little difference in the molecular weight (M w), structure and thermal stability. The TGA results showed that the thermal stability of quaternized curdlan was lower than curdlan. Turbidity analysis method shows that the aqueous solution of quaternized curdlan has good stability. The antibacterial activity of quaternized curdlan was investigated by disc-diffusion methods, which revealed that the quaternized curdlan with high DS had antibacterial effect against Escherichia coli, Staphylococcus and Fusarium. The antimicrobial test results showed that the antibacterial activities of quaternized curdlans against Staphylococcus were much better than E. coli, and Fusarium were much better than Staphylococcus.

Lauric diacid (LCDA), also known as 1,12-dodecanedioic acid, is used to develop a series of copolyesters along with 1,4-cyclohexanedicarboxylic acid (CHDA) and 1,4-butanediol (BDO). The resulting poly(butylene lauric dicarboxylate-co-butylene 1,4-cyclohexanedicarboxylate) (PBLC) is proved to be a random copolyester with three triad sequences. When the LCDA content increases from 20 to 60 mol%, Tm of the copolyester decreases from 133 to 57 °C. At the same time, the tensile modulus and strength decrease from 94 and 14 MPa to 40 and 5 MPa, respectively. Moreover, the elongation at break also drops from 640 to only 50%. However, further increasing the LCDA content to 80 mol%, the copolyester becomes amorphous with no Tm, and its tensile modulus, strength, and the elongation at break all improve significantly to 68 and 7 MPa, and over 1400%, respectively. More importantly, for the homo-polymer poly(butylene lauric dicarboxylate) (PBL), it has a relatively high Tm of 73 °C compared to that of polycaprolactone (PCL), but lower tensile modulus and strength, and significantly higher ductility, compared to those of PCL, linear low density polyethylene, and polybutylene succinate.

Interfacial solar steam generation is emerging as a promising high-efficiency strategy to produce clean water by harvesting and converting clean solar energy to the localized heat. It is highly desirable to introduce robust materials that are able to bear the extreme conditions for advanced applications of solar steam generation. Here, we demonstrate an all-in-one interfacial solar evaporator made from poly(p-phenylene benzobisoxazole) nanofiber (PBONF)/graphene oxide (GO) and PBONF/reduced graphene oxide (RGO) composite aerogels with high porosity, robust mechanical properties, and excellent thermal insulation performance. The evaporators of PBONF/RGO composite aerogel show fast and durable solar-vapor conversion with a high efficiency of 98.4 % under unconcentrated one sun irradiation. The PBONFs not only reinforce the mechanical properties of composite aerogels, but also affords them great potential applications in wastewater purification in some extreme environment, for instance, aerospace.

Dengue virus (DENV) is an arthropod-borne virus that has developed into a prominent global health threat in recent decades. The main causative agent of dengue fever, the virus infects an estimated 390 million individuals across the globe each year. Despite the sharply increasing social and economic burden on global society caused by the disease, there is still a glaring lack of effective therapeutics against DENV. In this study, betulinic acid, a naturally occurring pentacyclic triterpenoid was established as an inhibitor of DENV infection in vitro. Time-course studies revealed that betulinic acid inhibits a post-entry stage of the DENV replication cycle and subsequent analyses also showed that the compound is able to inhibit viral RNA synthesis and protein production. Betulinic acid also demonstrated antiviral efficacy against other serotypes of DENV, as well as against other mosquito-borne RNA viruses such as Zika virus and Chikungunya virus, which are commonly found co-circulating together with DENV. As such, betulinic acid may serve as a valuable starting point for the development of antivirals to combat potential DENV outbreaks, particularly in tropical and subtropical regions which make up a large majority of documented infections.

Assembling nanoscale building blocks derived from ultrastrong polymer fibers into ordered architectures should offer an effectively alternative way to access high-performance nanocomposites with extremely high strength and heat resistance for advanced applications. Poly( p -phenylenebenzobisoxazole) (PBO) fibers possess outstanding mechanical and thermal properties among the synthetic organic fibers. Here, commercial PBO fibers have been disintegrated into uniform nanofibers with the diameter of ca. 20 nm by a mixed acid treatment, and then served as a polymeric building block to be assembled into layered architectures through layer-by-layer deposition. The resulting (PBO-PBO) 50 films exhibit superior mechanical and thermomechanical properties with the modulus of 3.29 GPa, the toughness of 2.1 MJ m −3 , and the strength of 181.08 MPa. Through employing the poly(vinyl alcohol) (PVA) as a connecting layer in the deposition, the (PBO-PVA) 50 nanocomposite films possess remarkable mechanical properties demonstrated by the modulus of 6.48 GPa, the toughness of 4.6 MJ m −3 , and the strength of 304.34 MPa, due to the synergistic interfacial interaction between the PBO nanofibers and the matrix. In addition, the (PBO-PBO) 50 films possess the thermal stability up to 625 °C and excellent fire retardancy.

In this study, a novel stepwise rapid tracking strategy was reported to identify the active molecules from Ixeris sonchifolia Hance (IsH) in the treatment of coronary heart disease (CHD) based on "affinity mass spectrometry (MS)-atomic force microscopy (AFM) imaging" technology. First, vascular endothelial growth factor receptor 2 (VEGFR2) of the vascular endothelial growth factor (VEGF) signal transduction pathway located on the cell membrane was revealed to be the core target protein in CHD treatment through network pharmacology and bioinformatics. In addition, affinity MS screening based on VEGFR2 identified isochlorogenic acid A and luteolin-7-O-glucuronide as having stronger affinity with VEGFR2. Then, the active molecule was elucidated based on the observation that its actions accompanied the molecular morphological changes by AFM imaging and it could act on the binding pocket of VEGFR2 through molecular docking which further demonstrated the analysis and inference of AFM imaging. The methyl thiazolyl tetrazolium (MTT) assay finally confirmed that the active molecules specifically combined with the potential core target protein to protect the viability of cardiomyocytes, which identified the main potential active molecules in IsH for the treatment of CHD and provided a possible mechanism for the protective role of the drug. The technology established in this study could facilitate the rapid tracing of potential active molecules in traditional Chinese medicine (TCM), which would provide further a reference for research on quality, molecular mechanisms and new drugs.

Glutathione (GSH) has been studied for its neuroprotection value in several diseases, but the effect of GSH on intracerebral hemorrhage (ICH) is unclear. In this study, we examined the protective effects of GSH in an experimentally induced ICH model and investigated the relative mechanisms. Adult male C57BL/6j mice were randomized into Sham, ICH and GSH treatment groups. GSH was injected with the dose of 50, 100 or 200 mg/kg once per day for 3 days, starting immediately after operation. The results revealed a GSH-mediated improvement of neurological deficits score (NDS), motor and sensory functions impairment in a dose-dependent manner three days post ICH (p 0.01, GSH 200 vs ICH. Sham, n = 12; ICH, n = 9; GSH 50, n = 10; GSH 100, n = 10; GSH 200, n = 11) in addition to significantly reduced mortality rate (p = 0.2632, GSH 200 vs ICH. n = 12 per group) and damage volume (p 0.05, GSH 200 vs ICH. n = 12 per group). GSH treatment also attenuated injury measured by decreased brain edema (p 0.05, GSH 200 vs ICH. Sham, n = 10; ICH, n = 10; GSH 200, n = 12), blood-brain barrier disruption (p 0.05, GSH 200 vs ICH. Sham, n = 10; ICH, n = 10; GSH 200, n = 12), and histopathological damage (p 0.05, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8) 72 h after ICH. In addition, GSH treatment also decreased cell apoptosis (p 0.01, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8) and resulted in up-regulated protein expression of complex I (p 0.01, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8), which was consistent with an overall up-regulation of complex I function in mitochondria using Oxygraph-2 K high resolution respirometry (p 0.05, GSH 200 vs ICH. Sham, n = 4; ICH, n = 5; GSH 200, n = 6). In conclusion, GSH effectively improved the prognosis of ICH mice by attenuating neurological impairment, decreasing neural damage, and inhibiting apoptosis. The neuroprotection by GSH resulted from the up-regulation of mitochondrial oxidative respiration function. The results of our study suggest that GSH can be a potential therapeutic agent for ICH.

The high-quality polyacrylonitrile (PAN) precursor fibers are indispensable for the manufacture of high-performance carbon fibers. For the purpose of regulating microfibril structures and improving fiber quality, scanning electron microscopy, high-resolution transmission electron microscopy and the nitrogen adsorption measurement were carried out to investigate the microfibril alignment evolution in PAN fibers, which was obtained by different stretching fields during dry-jet wet spinning process. The interconnected microfibrillar network forming in coagulation bath was plastically elongated and gradually developed into the oriented microfibrils while the transverse lamellae formed. Then break-reorganization of the lamellae brought the remarkable enhancement of fiber crystallinity during the hot-treatment process. Finally, the well-aligned and regular microfibrils appeared due to the deep plastic deformation. There were three stages in the total evolution of microfibril alignment: the plastic deformation of microfibrillar network, the fragmentation of the original lamella, and the formation and development of regular microfibrils. The microfibrils in PAN fibers were stacked by crystal layers in an order and tightly manner. Served as excellent reinforcing elements, aligned microfibrils could efficiently improve the fiber mechanical properties. Compared with nascent fiber, the tensile strength of PAN precursor fiber increased by 1492% and its tensile modulus enhanced by 574%.

Ethanolic extracts of green tea leaves (GTE) and fenugreek seeds (FSE) were screened for their antibacterial activity against four food pathogenic strains using disc diffusion method. The two extracts revealed antimicrobial activity against selected bacterial strains. GTE showed the highest antibacterial activity to Escherichia coli and Staphylococcus aureus at a concentration of 1% with inhibition zone equal to 29.45 ± 0.64 mm and 25.68 ± 1.2 mm, respectively. In addition, the effect of GTE and FSE combined with chitosan coating on the shelf life of Pacific white shrimp (PWS) (Litopenaeus vannamei) during refrigerated storage have been studied. Our results indicated that using GTE or FSE during the refrigerated storage of PWS led to significantly decreased Total Volatile Bases Nitrogen, Thiobarbituric acid reacting substances, total bacterial count, and pH. The sensory properties of PWS have improved considerably in the samples treated GTE or FSE. These findings suggested that the application of chitosan coating combined with GTE or FSE to PWS is advisable to achieve better quality during refrigerated storage.

Decorative bamboo filament is a new material made with bamboo filament by weaving or adhesive. When it is used in indoor wall and ceiling decorations, the fire resistance of the decorative bamboo filament is very important. Guanylurea phosphate (GUP) flame retardants were used in this study to treat decorative bamboo filament. The microstructures before and after the flame retardant treatment were observed by environmental scanning electron microscopy. The effects on the heat release and smoke release were also evaluated with cone calorimetry. The resistance to mildew was tested before and after the modification. The results showed that the GUP fire retardants had good deposition in parenchyma cells. The treated samples containing 25% GUP effectively reduced the heat and smoke release. The peak value of heat release rate (PKHRR) and the total heat release (THR) in 115 s was respectively reduced by 44.9% and 42.2%; the peak value of smoke release rate (PKSPR), the total smoke production (TSP), and the specific extinction area (SEA) of treated decorative bamboo filament was respectively reduced 67.4%, 95%, and 94.4%. The prevention of mildew was slightly enhanced. The prevention rate of Trichoderma viride even reached 100%.

Chemokines have chemotactic properties on leukocyte subsets whose modulation plays a pivotal role in allergic inflammatory processes. Our present study was designed to investigate the anti-allergic and anti-inflammatory properties of desloratadine citrate disodium injection (DLC) and elucidate the molecular mechanisms of its anti-inflammatory properties. The anti-allergic effects of DLC were evaluated based on allergic symptoms, serological marker production and histological changes of the nasal mucosa in guinea pigs model of allergic rhinitis. The anti-inflammatory properties and molecular mechanisms of DLC were explored by studying the regulation of a set of chemokines and extracellular signal-regulated kinase (ERK)1/2 and nuclear factor-kappa B (NF-κB) pathways, after DLC treatment in guinea pigs model of allergic rhinitis in vivo and histamine-activated human nasal epithelial cells (HNECs) in vitro. In vivo model in guinea pigs, DLC alleviated the rhinitis symptoms, inhibited inflammatory cells infiltration in nasal lavage fluid (NLF) and histamine, monocyte chemotactic protein (MCP)-1, regulated on activation normal T cell expressed, and presumably secreted (RANTEs) and interleukin (IL)-8 release in sera and P-ERK1/2 and NF-κB activation in nasal mucosa. In vitro, DLC markedly inhibited histamine-induced production of MCP-1, RANTEs and IL-8 and suppressed c-Raf, mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK) and ERK1/2 activation in HNECs. These results provide evidence that DLC possesses potent anti-allergic and anti-inflammatory properties. The mechanism of action underlying DLC in allergic inflammation appears to be inhibition of the phosphorylation of ERK1/2, in addition to blocking of the NF-κB pathway.

The aim of the present study was to investigate the antitumor effects and possible mechanism of (-)-gossypol nanoparticles, loaded with vv polyethylene glycol-maleimide (mPEG-Mal), in vitro. Emulsification-volatilization was used to prepare the loaded (-)-gossypol nanoparticles. The toxicity of blank nanoparticles on human prostate cancer PC-3 cells and human prostate RWPE-1 cells was measured. The antitumor effects of the nanoparticles on PC-3 cells were evaluated by an MTT assay, acridine orange staining and transmission electron microscopy in vitro, and the results were compared with those of free (-)-gossypol. In addition, the mRNA expression levels of Bcl-2 and Bak were measured using semi-quantitative reverse transcription polymerase chain reaction. The growth inhibition activity of the loaded (-)-gossypol nanoparticles was found to be dose- and time-dependent, and similar to the activity of free (-)-gossypol. The nanoparticles induced apoptotic morphological changes on the PC-3 cells, downregulating the mRNA expression level of Bcl-2 and upregulating the mRNA expression level of Bak. Blank nanoparticles exhibited no evident toxicity on PC-3 and RWPE-1 cells at a high dose. Therefore, the mPEG-Mal loaded (-)-gossypol nanoparticles demonstrated a favorable antitumor activity and no toxicity. The nanoparticles were able to induce the apoptosis of prostate cancer cells; thus, may be a potential antitumor nanodrug.

In this study, novel antimicrobial peptides had been derived by enzymatic hydrolysis of filefish (Thamnaconus modestus) byproduct (HFBP). Different proteases, (papain [P], trypsin [T], neutrase [N], pepsin [PE], and the mixture I [PN] and mixture II [PT]) and different hydrolysis time (60, 120, 180, and 240 min), have been used to generate peptides with different lengths and amino acid sequences. The antimicrobial properties of HFBPs were tested, against Gram-positive and Gram-negative strains, using disc diffusion method. HFBP prepared after 120 min of the enzymatic hydrolysis by trypsin (HFBP-T) exhibited greatest antibacterial activities. Bacillus cereus 10451 (BC) and Salmonella enteritidis 10982 (SE) strains were most sensitive to HFBP-T with an inhibitory zone of 24.68 and 29.67 mm diameter and minimum inhibitory concentration of 1.25 and 2.5 mg/mL, respectively. Moreover, the antimicrobial activities of tested HFBPs increased significantly at low pH and temperature. The amino acid analysis showed that HFBP-T protein hydrolysate is high in an amino acid of proline, which probably contributes to the antimicrobial activity. The results obtained from scanning electron microscopy suggested that HFBPs might kill bacteria by acting on the cell wall of bacteria. Conclusively, the HFBP derived from filefish byproduct with biological activates is an interesting alternative to the use of waste from the fishing industry as natural antimicrobials in food stuff.

Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) has been an important afforestation species in northeast China. It has obvious defects of buckling and cracking easily, which are caused by its chemical components. Trametes versicolor (L.) Lloyd, a white-rot fungus, can decompose the cellulose, hemicellulose, and lignin in the wood. White-rot fungus was used to biologically degrade Chinese fir wood. The effects of different degradation time on the Chinese fir wood’s mechanical properties, micromorphology, chemical components, and crystallinity were studied. The results showed that the heartwood of Chinese fir was more durable than the sapwood and the durability class of Chinese fir was III. Trametes versicolor (L.) Lloyd had a greater influence on the mechanical properties (especially with respect to the modulus of elasticity (MOE)) for the sapwood. Trametes versicolor (L.) Lloyd degraded Chinese fir and colonized the lumen of various wood cell types in Chinese fir, penetrated cell walls via pits, caused erosion troughs and bore holes, and removed all cell layers. The ability of white-rot fungus to change the chemical composition mass fraction for Chinese fir was: hemicellulose > lignin > cellulose. The durability of the chemical compositions was: lignin > cellulose > hemicellulose. The crystallinity of the cellulose decreased and the mean size of the ordered (crystalline) domains increased after being treated by white-rot fungus.

As a Mongolian native medicine and Ewenki folk medicinal plant, Gentianella acuta has been widely used for the treatment of diarrhea, hepatitis, arrhythmia, and coronary heart disease. In the course of investigating efficacy compounds to treat diarrhea using a mouse isolated intestine tissue model, we found 70% EtOH extract of G. acuta whole plants had an inhibitory effect on intestine contraction tension. Here, nineteen constituents, including five new compounds, named as gentiiridosides A (1), B (2), gentilignanoside A (3), (1R)-2,2,3-trimethyl-4-hydroxymethylcyclopent-3-ene-1-methyl-O-β-d-glucopyranoside (4), and (3Z)-3-hexene-1,5-diol 1-O-α-l-arabinopyranosyl(1→6)-β-d-glucopyranoside (5) were obtained from it. The structures of them were elucidated by chemical and spectroscopic methods. Furthermore, the inhibitory effects on motility of mouse isolated intestine tissue of the above mentioned compounds and other thirteen iridoid- and secoiridoid-type monoterpenes (7–10, 13–16, 18, 19, 21, 22, and 25) previously obtained in the plant were analyzed. As results, new compound 5, some secoiridoid-type monoterpenes 7, 10, 12–14, 16, and 17, as well as 7-O-9′-type lignans 31 and 32 displayed significant inhibitory effect on contraction tension at 40 μM.

Corrugating medium was made from the solid waste of bamboo paper sludge and old corrugated container (OCC) pulp. The medium also incorporated additions of anion polyacrylamide as a retention agent and cationic starch as a strengthening agent. The estimated molecular mass of anion polyacrylamide, the addition level of anionic polyacrylamide, and the addition level of cationic starch were optimally designed using single-factor analysis. On this premise, the optimum addition level of the solid waste of bamboo paper sludge was found. The best process conditions for the corrugating medium included a base weight of 120 g/m-2, 10 wt.% bamboo paper sludge solid waste, 0.3 wt.% APAM (Estimated molecular mass of 600 × 104 Daltons), and 1.5 wt.% cationic starch. The apparent density, breaking length, and ring crush index were 0.53 g/cm-3, 2.51 km, and 7.48 N/mg-1, respectively, under the best process conditions. This finding could help satisfy the demand for materials used for making the corrugating medium and could support the full utilization of the solid waste of bamboo paper sludge to achieve higher value.

Styrene monomer (St) and dimethylaminoethyl methacrylate (DM) monomer were used to synthesize the amphiphilic random copolymer P(St-ran-DM) via free radical copolymerization. A Y-shaped microchannel was used enabling a controllable and fast mixing process to assist the formation of polymeric micelles which was triggered by a solvent exchange process when organic solutions of the polymer mixed with water. The effects of flow rate, polymer concentration, and microchannel dimensions on the characteristics of micelle were systematically investigated. The results showed that besides the effect of the flow rate, the chemical environment played an important role in determining the characteristics of the polymeric micelles.

Self-assembled polymeric micelles can be used as efficient particulate emulsifiers. Styrene (St) and dimethylaminoethyl methacrylate (DM) were used to synthesize the amphiphilic random copolymer P(St-co-DM). This copolymer self-assembles into spherical polymeric micelles. The polymeric micelles show surface activity and pH sensitivity for producing Pickering emulsion. The experiment shows that the stability of the emulsion increases with the micelle concentration. The emulsion can only be formed when the salt concentration is below a certain limiting value. Using the white oil as the oil phase, polymeric micelles have emulsification in a large pH range. The emulsifying performance of the polymeric micelles could be enhanced by raising the water/oil volume ratio.

This paper reports the manufacturing process for biodegradable paper sheeting with incorporation of bamboo paper sludge, fibers of poplar woods, and viscose fibers by wet-laid nonwoven technology. The best process conditions included a basis weight of 30 g/m2, a bamboo paper sludge content of 10 wt%, and a polyvinyl alcohol concentration of 4 wt%. The burst strength, tearing resistance, tensile properties, resistance to water, and degradation rate were 220.65 kPa, 60.00 N, 46.10 N, 153 Pa, and 56.18%, respectively, under the best process conditions. The biodegradable paper sheeting can satisfy the demand for replacement of agricultural plastic sheeting used for such purposes as moisture retention of soil and promotion of plant growth.

We have synthesized two low molecular weight organic molecules, PY and IN successfully, which selectively stain nucleolus and cytoplasm of living cells in 30 min, with a much lower uptake in the nucleus. Nucleic acids electrophoresis and digest test of ribonuclease indicate their markedly higher affinity for RNA, especially PY. Moreover their RNA localization in cells is further supported by digest test of ribonuclease, namely, the nucleolar fluorescence signal is distinctly lost upon treatment with RNase. And, the fact that live cells stained by PY and IN still possess physiological function can be confirmed: 1) MTT assay demonstrates that the mitochondria of cells stained remains its electron mediating ability, 2) Double assay of PY/IN and propidium iodide as well as trypan blue testing show that the membrane of cells stained still is intact. Importantly, compared with the only commercial RNA probe, SYTO RNA-Select, PY and IN exhibit much better photostability when continuously illuminated with 488 nm laser and mercury lamp. These results prove that PY and IN are very attractive staining reagents for visualizing RNA in living cells.

The effect of a hydroxyl radical generating system (HRGS), which contained FeCl3, sodium ascorbate, and different concentrations of H2O2, on the physiochemical properties of myofibrillar protein (MP) from squid mantles, has been investigated. The effect of different exposure times to HRGS was also considered. Compared to non-oxidized MP, a significant (p

We have shown that bitter peptides derived from the hydrolysates of pepsin digested fish protein can increase lymphocytes and lysozyme activity and improve fish survival in aquaculture. In this study, we investigated how the immune function of bitter peptides increases the phagocytes’ engulf of latex beads, and analyzed the antioxidation of myofibrillar protein in peeled shrimp during chilled storage with /without bitter peptides by evaluating the activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, and the effects of the total carbonyl and sulfhydryl. Also, the bitter peptides’ effect on the structural stability of muscles protein throughout oxidation was examined in vitro by both scanning electron microscope (SEM) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The engulf assay demonstrated phagocytosis increased from the control group to the highest bitter peptide concentration of 1.2 mg/ml; the bitter peptides had a significant DPPH radical-scavenging activity, reducing the power of ferric ions and metal chelating ability. Chemical analysis showed that myofibrillar protein in chilled storage was highly susceptible to oxidation, and the results indicate that treating peeled shrimp with bitter peptides before chilled storage significantly decreases the formation of carbonyl derivatives and reduces the loss of thiol groups when compared with the water treated sample. In addition, the results of both SEM and SDS-PAGE confirm that there was less distortion of tissue structure and less degradation of the protein in the samples treated with bitter peptides. Bitter peptides are both beneficial for fish disease control and preservation of marine food. Keywords: Bitter peptides, Myofibrillar protein, Antioxidation, Innate immunity, Scanning electronic microscopy (SEM)

Rationale: Acute myeloid leukemia (AML) is a malignantly clonal and highly heterogeneous disease. Although the treatment of AML has brought promising outcomes for younger patients, prognosis of the elderly remains dismal. Innovative regimens are increasingly necessary to be investigated. Patient concerns: We present an 86-year-old AML patient with fever, cough, and sputum production. Diagnoses: A diagnosis of AML with maturation (AML-M2) and AML1/ETO was made. Interventions: The patient was treated with a regimen of Homoharringtonine coupled with arsenic trioxide. Outcomes: The AML-M2 patient with AML1/ETO achieved incomplete remission, but showed few toxic side effects and improved survival. Besides, we analyzed the dynamic counts of complete blood cells during the treatment. The count of white blood cell had a positive correlation with the percentage of blast cells (r = 0.65), both of which had a negative correlation with the percentage of segmented neutrophils (r = –0.63, –0.89). Lessons: Homoharringtonine and arsenic trioxide may induce both the apoptosis and differentiation of leukemic cells in AML-M2 with AML1/ETO.

Ammuxetine (AMT), a novel chiral antidepressant candidate compound, exhibits better antidepression effects than duloxetine in different animal models. In this article, a chiral derivatization method, combined with online solid phase extraction (online SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), was developed for the chiral separation of AMT enantiomers after administration of racemic AMT to dogs. The derivatization reaction employed 2,3,4,6-tetra-O-acetyl-b-glucopyr-anosyl isothiocyanate (GITC) as a precolumn chiral derivatization reagent. A SPE column Retain PEP Javelin (10 × 2.1 mm) was used to remove proteins and other impurities in plasma samples. The enantiomeric derivatives were separated on a ZORBAX SB-C18 column (50 × 2.1 mm × 3.5 μm) with an isocratic elution procedure. The selected multiple reaction monitoring mode of the positive ion was performed and the parent to the product transitions m/z 681.0/543.1 and m/z 687.4/543.1 were used to measure the derivatives of AMT and duloxetine (internal standard) with electrospray ionization. The method was validated in terms of specificity, linearity, sensitivity, precision, accuracy, matrix effect, and stability. The method was applied to a pharmacokinetics study of AMT racemate in dogs. The results suggested that the pharmacokinetic of AMT enantiomers might be stereoselective in dogs.