RESUMO
In this work, we presented a novel encoding method for tactile communication. This approach was based on several tactile sensory characteristics of human skin at different body parts, such as the head and neck, where location coordinates in the three-dimensional (3D) space were clearly mapped in the brain cortex, and gentle stimulations of vibrational touching with varied strengths were received instantly and precisely. For certain applications, such as playing cards or navigating walk paths for blinded people, we demonstrated specifically designed code lists with different patterns of tactile points in varied temporal sequences. By optimizing these codes, we achieved excellent efficiency and accuracy in our test experiments. As this method matched well with the natural habits of tactile sensory, it was easy to learn in a short training period. The results of the present work have offered a silent, efficient and accurate communication solution for visually impaired people or other users.
Assuntos
Percepção do Tato , Pessoas com Deficiência Visual , Dispositivos Eletrônicos Vestíveis , Humanos , Tato , PeleRESUMO
Paeonone A (1), a unique nonanortriterpenoid, and a new octanortriterpenoid, paeonone B (2), were isolated from the roots of Paeonia lactiflora, together with a known analogue, palbinone (3). Paeonone A (1) is the first example of naturally occurring nonanortriterpenoid with a diketo acid group. Extensive NMR and HRESIMS experiments were applied to identify the structures of 1 and 2, and their absolute configurations were solved by single-crystal X-ray diffraction and ECD data. Biological properties of 1-3 were explored against pancreatic lipase and cancer cell lines.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Inibidores Enzimáticos/farmacologia , Lipase/antagonistas & inibidores , Paeonia/química , Raízes de Plantas/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Lipase/metabolismo , Estrutura Molecular , Pâncreas/enzimologia , Relação Estrutura-AtividadeRESUMO
According to human carboxylesterase 2(hCE2) inhibitors reported in the literature, the pharmacophore model of hCE2 inhibitors was developed using HipHop module in Discovery Studio 2016. The optimized pharmacophore model, which was validated by test set, contained two hydrophobic, one hydrogen bond acceptor, and one aromatic ring features. Using the pharmacophore model established, 5 potential hCE2 inhibitors(CS-1,CS-2,CS-3,CS-6 and CS-8) were screened from 20 compounds isolated from the roots of Paeonia lactiflora, which were further confirmed in vitro, with the IC_(50) values of 5.04, 5.21, 5.95, 6.64 and 7.94 µmol·L~(-1), respectively. The results demonstrated that the pharmacophore model exerted excellent forecasting ability with high precision, which could be applied to screen novel hCE2 inhibitors from Chinese medicinal materials.
Assuntos
Carboxilesterase , Carboxilesterase/antagonistas & inibidores , Carboxilesterase/metabolismo , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e HidrofílicasRESUMO
In a continuing search for potential inhibitors against human carboxylesterases 1A1 and 2A1 (hCES1A1 and hCES2A1), an EtOAc extract of the roots of Paeonia lactiflora showed strong hCES inhibition activity. Bioassay-guided fractionation led to the isolation of 26 terpenoids including 12 new ones (1-5, 7-12, and 26). Among these, sesquiterpenoids 1 and 6, monoterpenoids 10, 11, and 13-15, and triterpenoids 18-20, 22, and 24-26 contributed to the hCES2A1 inhibition, in the IC50 range of 1.9-14.5 µM, while the pentacyclic triterpenoids 18-26 were responsible for the potent inhibitory activity against hCES1A1, with IC50 values less than 5.0 µM. The structures of all the compounds were elucidated using MS and 1D and 2D NMR data, and the absolute configurations of the new compounds were resolved via specific rotation, experimental and calculated ECD spectra, and single-crystal X-ray diffraction analysis. The structure-activity relationship analysis highlighted that the free HO-3 group in the pentacyclic triterpenoids is crucial for their potent inhibitory activity against hCES1A1.
Assuntos
Inibidores Enzimáticos/farmacologia , Paeonia , Extratos Vegetais/farmacologia , Raízes de Plantas , Carboxilesterase/antagonistas & inibidores , Linhagem Celular Tumoral , Glucosídeos , Humanos , Estrutura Molecular , Monoterpenos , Sesquiterpenos , Relação Estrutura-AtividadeRESUMO
OBJECTIVE: To study the neuroprotective effect of inhalation of volatile oil of Cang Ai (VOCA) on cerebral ischemia-reperfusion injury model by MRI diffusion tensor imaging. METHODS: Twenty-four healthy adult male SD rats were randomly divided into sham operation group, model (middle cerebral artery occlusion (MCAO) ) group and VOCA group. Evaluated the degree of neurological impairment of rats in each group immediately after successful establishment of model or 7 d later according to Zea Longa scoring. Coronal diffusion tensor imaging (DTI) scan was performed at 3 h, 3 d, and 7 d after the model successfully established by using 7.0 T magnetic resonance imaging. Measured the apparent diffusion coefficient (ADC) and anisotropy score (FA) of the DTI in the striatal region and the motion flat zone of the maximum infarct level and then calculate the relative apparent diffusion coefficient (rADC) and relative anisotropy score (rFA). TTC staining was used to evaluate the cerebral infarction volume of rats in each group at 7 d post model establishment, and the correlation analysis of rFA, rADC and neural score was performed. RESULTS: No neurological defect was detected in mice in the sham operation group. The MCAO group and the VOCA group showed neurological defect to different degrees. The neurological function score of the VOCA group was obviously lower than that of MCAO group at 7 th day (P<0.05). The DTI scan results showed that the rADC value of striatum of rats in VOCA group was higher than that in MCAO group at 3 h and 3 d after modeling (P<0.05), while there was no significant difference between the three groups at 7 th day. The rADC value of the motor cortex in the VOCA group was higher than that in the MCAO group at 3 h after modeling (P<0.01), and there was no significant difference at 3 rdday and 7 thday. The rFA value of striatum in VOCA group was higher than that in MCAO group at 3 rd day and 7 th day after modeling (P<0.05). There were no significant differences in rFA value between the MCAO and the VOCA group at three time points. TTC staining results showed that there was no infarcted area in the sham operation group, and the infarct volume in the VOCA group was smaller than that of the MCAO group (P<0.05). Correlation analysis showed that the striatum rFA value was highly correlated with neurological scores (r=ï¼0.847, P<0.01). CONCLUSION: For the first time, we found that VOCA can effectively protect the neurological function of MCAO rats by reducing the toxic edema of cells in the ischemic area and accelerating the recovery of nerve fiber bundles after cerebral ischemia and reperfusion. rFA and rADC values can be used as effective indicators to evaluate the recovery of nerve function after cerebral ischemia and reperfusion.
Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Óleos Voláteis , Traumatismo por Reperfusão , Animais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Imagem de Tensor de Difusão , Infarto da Artéria Cerebral Média , Masculino , Fármacos Neuroprotetores/farmacologia , Óleos Voláteis/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/diagnóstico por imagem , Traumatismo por Reperfusão/tratamento farmacológico , PesquisaRESUMO
Fractionation of an aqueous extract of the air-dried roots of a traditional Chinese medicinal plant, Paeonia lactiflora, yielded the new monoterpenoid glycosides 1-10. Their structures were assigned via spectroscopic techniques, and the absolute configurations of 1, 4-6, and 8 were verified via chemical methods, specific rotation, and electronic circular dichroism data. Compounds 1-4 are rare compared to the reported cage-like paeoniflorin derivatives; that is, they comprised two monoterpenoidal moieties. In the in vitro assay, compounds 5, 8, and 9 showed weak inhibitions against lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophages, with IC50 values of 64.8, 60.1, and 97.5 µM, respectively.
Assuntos
Glicosídeos/química , Glicosídeos/farmacologia , Monoterpenos/química , Monoterpenos/farmacologia , Paeonia/química , Raízes de Plantas/química , Animais , Linhagem Celular , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7RESUMO
A new sesquiterpenoid ester glycoside (1) and a new monoterpenoid ester glycoside (2) have been isolated from an ethanol extract of the twigs of Litsea cubeba. Their structures were elucidated by extensive 1D- and 2D-NMR experiments, and the absolute configurations were determined by chemical methods, specific rotation, and a combination of experimental and theoretically calculated electronic circular dichroism spectra. Compound 1 exhibited selective cytotoxicity against A549 and HCT-8 cell lines with the IC50 values of 8.9 and 9.6 µM, respectively.
Assuntos
Glicosídeos/química , Litsea/química , Terpenos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Estrutura MolecularRESUMO
Nineteen compounds were isolated from the water-soluble extract of the dry roots of Paeonia lactiflora by using various chromatographic techniques. Their structures were identified by MSï¼ NMR and other spectroscopic analysis as paeoniflorin(1)ï¼ 4-O-ethylpaeoniflorin(2)ï¼ 2'-O-benzoylpaeoniflorin(3)ï¼ benzoylpaeoniflorin(4)ï¼ 4"-hydroxy-benzoyloxypaeoniflorin(5)ï¼ moudanpioside C(6)ï¼ 6'-O-benzoyl-4"-hydroxy-3"-methoxy-paeoniflorin(7)ï¼ paeoniflorin B(8)ï¼ 6-O-benzoylalbiflorin(9)ï¼ secoisolariciresinol (10)ï¼ (+)-lyoniresinol(11)ï¼ dihyrodehydrodiconiferyl alcohol(12)ï¼ (7Sï¼8S)-threo-7ï¼9ï¼9'-trihydroxy-3ï¼3'-dimethoxy-8-O-4'-neolignan(13)ï¼ (+)-neo-olivil (14)ï¼ [(3S)-5-methyl-2ï¼3-dihydro-1-benzofuran-3-yl]methanol(15)ï¼ 5-hydroxy-3S-hydroxymethyl-6-methyl-2ï¼3-dihydrobenzofuran(16)ï¼ (+)-(R)-2-hydroxy-1-(4-methoxyphenyl)-1-propan-1-one(17)ï¼ (+)-(2R)-1-(4-hydroxy-3-methoxyphenyl)-2-propanol(18)ï¼ (+)-(4S)-(2E)-4-hydroxy-2-nonenoic acid(19). Compounds 15 and 18 are new natural productsï¼ while compounds 10ï¼ 11ï¼ 13ï¼ 14ï¼ 17 and 19 are isolated from the genus Paeonia for the first time.
Assuntos
Paeonia , Monoterpenos , Extratos Vegetais , Raízes de Plantas , ÁguaRESUMO
The air-dried twigs of Litsea cubeba, a traditional Chinese medicinal tree, afforded 10 new aromatic glycosides (1-10) and 26 known analogues. Their structures were assigned by extensive 1D and 2D NMR experiments, and the absolute configurations were resolved by chemical methods, electronic circular dichroism, specific rotation, and X-ray crystallographic analysis. Compound 4 is the first example of a naturally occurring homoneolignan glucoside. Compounds 4, 6-8, and the known neolignan glucosides (11, 12, and 14) at respective 10 µM concentrations were found to reduce acetaminophen-induced HepG2 cell injury with 30.5-46.0% inhibitions. Furthermore, compounds 12 and 15 demonstrated moderate inhibitory activities against HDAC1, with IC50 values of 3.6 and 4.6 µM, respectively.
Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Litsea/química , Caules de Planta/química , Acetaminofen/farmacologia , Algoritmos , Cristalografia por Raios X , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Células Hep G2 , Humanos , Concentração Inibidora 50 , Lignanas/química , Lignanas/isolamento & purificação , Lignanas/farmacologia , Lipopolissacarídeos/farmacologia , Conformação Molecular , Estrutura Molecular , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/químicaRESUMO
Twenty five known aromatic glycosides (1-25) and three known sesquiterpene glycosides (26-28) have been isolated from the twigs of Litsea cubeba by using various chromatographic techniques. Their structures were identified by spectroscopic data analysis (MS, IR, 1D and 2D NMR) as (7S,8R)-dehydrodiconiferyl alcohol 4,9'-di-O-ß-D-glucopyranoside(1),(7S,8R)-5-methoxydihydrodehydrodiconiferyl alcohol 4-O-ß-D-glucopyranoside(2), (7S,8R)-urolignoside(3), (7R,8S)-dihydrodehydrodiconiferyl alcohol 4-O-ß-D-glucopyranoside(4), saposide B(5), lanicepside A(6), matairesinol-4-O-ß-D-glucopyranoside (7), tyraxjaponoside B(8), (+)-lyoniresinol-9'-O-ß-D-glucopyranoside (9), alaschanisoside A (10), syringin (11), psoralenoside (12), isopsoralenoside (13), scopolin(14), 2,6-dimethoxy-4-hydroxyphenol-1-O-ß-D-glucopyranoside (15), 3-hydroxy-4,5-dimethoxyphenyl-ß-D-glucopyranoside (16), 2-(3,4-dihydroxyphenyl)ethyl-ß-D-glucopyrnoside (17), 2-(4-dihydroxyphenyl)ethyl-ß-D-glucopyranoside (18), (+)-catechin-7-O-ß-D-glucopyranoside (19), 3'-O-methylepicatechin-7-O-ß-D-glucopyranoside (20), kaempferitrin (21), quercetin-3-O-α-L-rhamnopyranside (22), kaempferol-3-O-ß-D-glucopyranoside (23), kaempferol 3-O-ß-D-glucopyranosyl(1â2)-O-ß-D-galactopyr anoside-7-O-α-L-rhamnopyranoside (24), quercetin 3-O-α-L-rhamnopyranosyl(1â6)-O-ß-D-glucopyranosyl(1â3)-O-α-L-rhamnopyranosyl(1â2)-O-ß-D-glucopyranoside (25), staphylionoside D(26), vomifoliol 9-O-ß-D-glucopyranoside (27), dihydrovomifoliol-O-ß-D-glucopyranoside (28). Compounds 1-21 and 24-28 were obtained from this genus for the first time.
Assuntos
Medicamentos de Ervas Chinesas , Glicosídeos/isolamento & purificação , Litsea/química , Compostos Fitoquímicos/isolamento & purificação , Cromatografia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , ÁguaRESUMO
Two new phenylpropanoids(1 and 2), together with thirteen known compounds(3-15), have been isolated from the root of Paeonia lactiflora by using various chromatographic techniques. Their structures were identified by spectroscopic data analysis(MS,IR,1D and 2D NMR)as(+)-(7R,8R)-1-guaiacyl-1,2-propanediolacetonide(1),(-)-(7R,8S)-1-guaiacyl-1,2-propanediolacetonide(2),O-senecioyllomatin(3),O-angeloyllomatin(4),(+)-cis-3'-senecioyloxy-4'-angeloyloxy-3',4'-dihydroseselin(5),columbianadin(6), benzyl 2,5-dihydroxybenzoate(7),3,6-dimethyl-5-hydroxyBenzo-furan(8),(S)-evofolin-A(9),2,3-dihydroxy-4-methoxyacetophenone(10), 2,5-dihydroxy-4-methoxyacetophenone(11), 2,5-dihydroxy-4-methyl acetophenone(12),ethyl 4-hydroxybenzoate(13), vanillic acid(14),and 4-hydroxy-3-methoxybenzaldehyde(15).Compounds 1 and 2 were new compounds,and compounds 3-9 were obtained from the genus Paeonia for the first time.
Assuntos
Paeonia/química , Extratos Vegetais/química , Raízes de Plantas/química , Acetatos , Acetofenonas , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificaçãoRESUMO
A new aporphine alkaloid (1), together with five known analogues (2-6), has been isolated from the branch of Litsea greenmaniana by using various chromatographic techniques. Their structures were identified by spectroscopic data analysis ( MS, IR, 1D and 2D NMR) as 2,9-dihydroxy-1,10-dimethoxy-4,5-dihydro-7-oxoaporphine (1), laurotetanine (2), N-methyllaurotetanine (3), isodomesticine (4), isocorydine (5), and norisocorydine (6). Compound 1 was a new compound, and compounds 2-6 were obtained from this plant for the first time.
Assuntos
Alcaloides/química , Aporfinas/química , Medicamentos de Ervas Chinesas/química , Litsea/química , Estrutura Molecular , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
The nitrogen cycle is of great importance for material circulation and energy flow in lake ecosystems. It is driven by microorganisms in lake sediments and can contribute to balancing lake ecosystems. In this study, physical and chemical properties of the sediments sampled from Hongfeng Lake in Guizhou Province were assayed and analyzed using metagenomics to reveal relevant microorganisms, functional genes, metabolic pathways, and their relationships throughout nitrogen metabolism. The results showed that bacteria were dominant, and the top three relative abundant genera were Thiobacillus ï¼16.64%ï¼, Rubrivivaxï¼9.43%ï¼, and Nitrospira ï¼7.09%ï¼. Only six pathways, including nitrogen fixation, nitrification, denitrification, assimilatory nitrate reduction, dissimilatory nitrate reduction, and complete nitrification, were detected in total, of which denitrification and dissimilatory nitrate reduction were the primary processes, but anaerobic ammonia oxidation was not detected. Bacteria and archaea participated in these six pathways, while eukaryotes only functioned in dissimilatory nitrate reduction, denitrification, and complete nitrification. Ammonia nitrogen, nitrate nitrogen, and total phosphorus, as main environmental factors affecting the distribution of functional genes for nitrogen metabolism, differentiated with each other in their respective real-world conditions. A positive correlation ï¼95.04%ï¼ was observed between the functional genes and microorganisms, and narG, narZ, and nxrA possessed the highest abundance and the highest host genes. On this basis, these findings are expected to further elucidate the nitrogen cycle of typical karst lakes in Guizhou Province.
Assuntos
Archaea , Bactérias , Sedimentos Geológicos , Lagos , Nitrogênio , Lagos/microbiologia , Sedimentos Geológicos/microbiologia , China , Nitrogênio/metabolismo , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética , Archaea/genética , Archaea/metabolismo , Archaea/classificação , Redes e Vias Metabólicas , Desnitrificação , Nitrificação , Thiobacillus/metabolismo , Thiobacillus/genética , Ciclo do Nitrogênio , Fixação de NitrogênioRESUMO
The incidence rate of diabetes in pregnancy is about 20%, and diabetes in pregnancy will have a long-term impact on the metabolic health of mothers and their offspring. Mothers may have elevated blood glucose, which may lead to blood pressure disease, kidney disease, decreased resistance and secondary infection during pregnancy. The offspring may suffer from abnormal embryonic development, intrauterine growth restriction, obesity, autism, and other adverse consequences. Resveratrol (RSV) is a natural polyphenol compound, which is found in more than 70 plant species and their products, such as Polygonum cuspidatum, seeds of grapes, peanuts, blueberries, bilberries, and cranberries. Previous studies have shown that RSV has a potential beneficial effect on complex pregnancy, including improving the indicators of diabetes and pregnancy diabetes syndrome. This article has reviewed the molecular targets and signaling pathways of RSV, including AMP-activated protein kinase, mitogen-activated protein kinases, silent information regulator sirtuin 1, miR-23a-3p, reactive oxygen species, potassium channels and CX3C chemokine ligand 1, and the effect of RSV on gestational diabetes mellitus (GDM) and its complications. RSV improves the indicators of GDM by improving glucose metabolism and insulin tolerance, regulating blood lipids and plasma adipokines, and modulating embryonic oxidative stress and apoptosis. Furthermore, RSV can ameliorate the GDM complications by reducing oxidative stress, reducing the effects on placentation, reducing the adverse effects on embryonic development, reducing offspring's healthy risk, and so on. Thus, this review is of great significance for providing more options and possibilities for further research on medication of gestational diabetes.
RESUMO
This article investigates the effect of pretilt angle on disclination lines of liquid crystal (LC) lenses. When the pretilt angle of LCs is higher than 7°, the disclination lines are reduced and are moved to the boundary of the LC lens. The disclination lines at the boundary do not influence the focused beam profile of the LC lens. As the pretilt angle of LCs further increases, the disclination lines at the boundary become almost invisible. However, the interference rings become asymmetrical. The response time of an LC lens with a pretilt angle higher than 7° is â¼60% of the conventionally homogeneous LC lens. This value is a result of the decrease in the rotation angle of the LCs and the reduced disclination lines.
RESUMO
OBJECTIVE: To analyze the misdiagnosed cases with benign paroxysmal positional vertigo (BPPV). METHODS: During October 2010 to January 2011, a total of 287 patients with dizziness visited the Dizziness Clinic at Changzheng Hospital, Second Military Medical University. Forty-eight misdiagnosed cases with BPPV were collected and their clinical data were analyzed. All 48 cases were diagnosed by the Dix-Hallpike or Roll test maneuver. RESULTS: (1) CLINICAL FEATURES: there were 38 females and 10 males with an average age of 54 ± 12 years old (range: 31 - 87). Posterior semicircular canal was involved in 75.0% (36/48) whereas the horizontal semicircular and multiple canals in 20.8% (10/48) and 4.2% (2/48) respectively. All patients were treated successfully. And 41 cases (85.4%) were cured on the first visiting day. Recurrences of BPPV occurred in 6 cases during the follow-up. (2) The initial visiting departments consisted of the department of general internal medicine 43.8% (21/48), department of neurology 27.1% (13/48), department of osteology 18.7% (9/48), ear, nose & throat (ENT) department 2.1% (1/48) and other departments 8.3% (4/48). In addition, 68.7% (33/48) of them frequented the general out-patient clinics during their initial visits and the other 31.3% (15/48) used the emergency services. (3) The initial diagnoses included vertebrobasilar insufficiency/cerebral circulation insufficiency 27.1% (13/48), cervical spondylosis 27.1% (13/48), cerebral infarction 4.2% (2/48), Meniere's disease 2.1% (1/48) and others 10.4% (5/48); Besides, 29.1% (14/48) of them had no diagnosis. (4) The average clinic visits per patient were 3.4 times (164 visits/48 cases). (5) The most commonly performed tests included brain computed tomography (CT) (28 person-times), cervical magnetic resonance imaging (MRI) (19 person-times), brain MRI (18 person-times), cervical radiography (18 person-times) and cervical CT (8 person-times). CONCLUSION: In these misdiagnosed cases of BPPV, most of them were middle-aged women. They were most likely to have their first consultations in the departments of general internal medicine and neurology. Therefore these two departments should pay more attention to applying the maneuver of Dix-Hallpike or Roll test so as to reduce the misdiagnosis of BPPV and the waste of healthcare resources.
Assuntos
Erros de Diagnóstico , Vertigem/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Vertigem Posicional Paroxística Benigna , Tontura/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
To preliminarily explore the antibiotic concentration distribution characteristics of Guizhou Chishui River basin surface water and potential ecological risks, we used solid phase extraction liquid chromatography tandem mass spectrometry (SPE-HPLC- MS) to analyze 21 types of antibiotics in surface water samples. Twelve types of antibiotics were detected in the Chishui River basin surface water, and the total concentrations of ofloxacin, sulfadiazine, and trimethoprim ranged from ND-1166.97 ng·L-1, with a detection rate of 100%. On average, the highest concentration of the three types of antibiotics detected were ofloxacin (221.59 ng·L-1), tetracycline (13.18 ng·L-1), and sulfadiazine (4.11 ng·L-1), and the antibiotic concentration distribution showed the following order of characteristics:downstream (359.41 ng·L-1) > midstream(224.59 ng·L-1) > upstream (179.72 ng·L-1). The ecological environment risk assessment results indicated the largest risk for downstream W21, tetracycline, doxycycline, enrofloxacin, norfloxacin, and erythromycin. The risk quotient revealed that lincomycin had a medium-risk level, and ofloxacin had a high-risk level. This shows that antibiotics in the waters of the Chishui River basin may cause certain ecological risks.
Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Antibacterianos/análise , China , Medição de Risco , Rios , Poluentes Químicos da Água/análiseRESUMO
Methanotrophs are important and unique prokaryotes widely distributed in the nature. They can oxidize methane and live at a moderate temperature in the conditions withpH=7. In addition, many methanotrophs have been isolated from various special conditions within a wide range of pH value and temperature, including acid sphagnum moss wetlands, acid forest soils, hot springs and high-temperature geothermal areas near volcanic craters, soda-saline lakes, and marine sediments. Here, we introduced the classification, properties and influencing factors of methanotrophs in these special conditions, and reviewed relevant technological researches and engineering applications, with the aim to facilitate further studies of natural biodiversity as well as global carbon and hydrogen cycles.
Assuntos
Metano , Sphagnopsida , Bactérias , Lagos , Oxirredução , FilogeniaRESUMO
With great practical potential of aerobic methane coupled to denitrification (AME-D) in deep denitrification of tailwater in urban sewage plants, an AME-D extreme denitrification system with low concentration of methane, was established in an improved denitrification biofilter. The finding indicated that in an intermittent operation mode, the average concentration of total nitrogen and ammonia nitrogen in the effluent could reach 1.05 mg·L-1 and 0.54 mg·L-1, and the average removal rate was 94.77% and 93.30%, respectively. According to Raman spectral analysis, the crests formed by NO3- symmetric stretching disappeared, and crests formed by the vibration and absorption, where the outer alcohol COH plane or the C-H plane was bent, were significantly enhanced, so the intermediate products produced during which methane was oxidized may be alcohols. 16S rRNA gene sequencing results showed that dominant methanotrophs included Methylocystis (0.27%), Methylosarcina (0.10%), and Methyloparacoccus (0.12%), dominant denitrifying bacteria were Pseudomonas (56.92%), Paenibacillus (3.52%), and Lysinibacillus (3.00%), and the dominant nitrifying bacteria were Nitrospira (0.1%) in this system. Thus, it could be concluded that synergism of aerobic methanotrophs, denitrifying bacteria, and nitrifying bacteria could lead to extreme denitrification.
RESUMO
The interaction of paeoniflorin with human serum albumin (HSA) was investigated using fluorescence, UV-vis absorption, circular dichroism (CD) spectra and molecular docking techniques under simulative physiological conditions. The results clarified that the fluorescence quenching of HSA by paeoniflorin was a static quenching process and energy transfer as a result of a newly formed complex (1:1). Paeoniflorin spontaneously bound to HSA in site I (subdomain IIA), which was primarily driven by hydrophobic forces and hydrogen bonds (ΔH° = - 9.98 kJ mol-1, ΔS° = 28.18 J mol-1 K-1). The binding constant was calculated to be 1.909 × 103 L mol-1 at 288 K and it decreased with the increase of the temperature. The binding distance was estimated to be 1.74 nm at 288 K, showing the occurrence of fluorescence energy transfer. The results of CD and three-dimensional fluorescence spectra showed that paeoniflorin induced the conformational changes of HSA. Meanwhile, the study of molecular docking also indicated that paeoniflorin could bind to the site I of HSA mainly by hydrophobic and hydrogen bond interactions.