RESUMO
Based on the continuous inventory data of forest resources in Zhejiang Province in 2019 and 2021, we used statistical methods such as polynomial regression to analyze the impacts of topography and forest spatial structure on average annual diameter at breast height (DBH) growth of main pioneer tree species in natural broad-leaved mixed forests. The results showed that DBH of Schima superba, Quercus glauca, Quercus fabri, Lithocarpus glaber, Castanopsis eyrei, and Castanopsis sclerophylla were between 5-50.8, 5-41.5, 5-50.8, 5-43.9, 5-55.5, and 5-46.1 cm, respectively. We classified all the trees into three classes based on DBH: small (6-12 cm), medium (12-14 cm), and large (>26 cm). The average annual DBH growth of S. superba and Q. glauca was the highest on semi-shady slope and shady slope, with increases of 2.9%-15.7% and 1.1%-41.2%, respectively. The average annual DBH growth of large-diameter S. superba, L. glaber, C. eyrei and C. sclerophylla decreased with the increase of slope, with a maximum decrease of 27.0% for S. superba, with no significant difference among small- and medium-diameter trees as a whole. The slope position did not affect the annual DBH growth of small-diameter trees, while that of medium- and large-diameter S. superba, Q. glauca, and large-diameter Q. fabri, L. glaber decreased with the change of slope position from downhill, mesoslope, uphill to ridge, with a maximum decrease of 28.1% for L. glabe, and the major-diameter C. eyrei was on the contrary. Appropriate increase in the mingling was beneficial to the average annual DBH growth of medium- and large-diameter trees. Moderate mixing was suitable for S. superba, while low degree mixing and moderate mixing was suitable for Q. glauca, Q. fabri and L. glaber, and intensive mixing was suitable for C. eyrei and C. sclerophylla. No significant difference was observed for minor-diameter trees under the mingling. The neighborhood comparison only had a significant effect on the average annual DBH growth of large-diameter Q. glauca, Q. fabri, and L. glaber, which was significantly higher under subdominance-moderation than moderation-inferiority. The average annual DBH growth in the study area was mainly affected by aspect and mixing degree.
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Pinus , Quercus , Árvores , Florestas , ChinaRESUMO
OBJECTIVE: In this work, we have used histopathology as the gold standard for the diagnosis, calculated the sensitivity and positive predictive value (PPV) of computed tomography (CT), and analyzed the CT and clinical characteristics of pathologically proven elastofibromas. METHODS: A systematic retrospective analysis was performed on all patients with infrascapular lesions who were treated in the hospital from 2006 to 2018. CT and histopathological examinations were performed for all cases, and the CT sensitivity and PPV for the diagnosis of elastofibroma were calculated. 12 of 53 cases (20 lesions) underwent enhanced CT scan after CT plain scan, and the related clinical and CT features of elastofibromas have been discussed. RESULTS: Of the 54 patients treated during the study, CT diagnosis was consistent with histopathology in 53 cases. One was a false-positive patient. The PPV and sensitivity of the CT in the diagnosis of elastofibroma were 93.3% (95% CI 68.0%-99.8%) and 100%, respectively. The CT values of 12 patients with 20 lesions on plain and enhanced scans were statistically significant (P=0.001). The prevalence of elastofibromas in males and females was statistically significant (P=.000). There was no statistically significant difference in the incidence of left and right elastofibromas (P=0.752). There was no significant difference in the volume of left and right lesions (P=0.209) and the volume of elastofibromas between males and females (P=.474). CONCLUSION: CT is the most practical tool for the evaluation of elastofibromas in the infrascapular region.
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Artificial light at night is rapidly spreading and has become an important component of global change. Although numerous studies have focused on its potential ecological impacts, the physiological response mechanisms of landscape plants to artificial light at night have rarely been quantified. With common landscape shrubs in subtropical regions of China, Hydrangea paniculata, Photinia fraseri and Ligustrum japonicum, as test materials, we exa-mined the responses of antioxidant enzyme system and biomass in the light environment at night under different light quality (yellow light, white light) with different light intensities (20, 40, 60 lx) . The results showed that artificial light at night significantly increased the membrane peroxidation, stimulated plant antioxidant protection systems and raised the antioxidant enzyme activities of the three species. The effects of light quality on plant antioxidant enzymes varied across dspecies. The peroxidase (POD) and catalase (CAT) activities of H. paniculata under white light were 1.5 and 1.3 times as that under yellow light, respectively. Both enzyme activities of P. fraseri were 1.1 times as that under white light than under yellow light. The activities of two enzymes in L. japonicum under white light were 88.6% and 99.5% of those under yellow light, respectively. The antioxidant enzyme activities of the three species increased with increasing light intensity at night, whereas the contents of malondialdehyde increased rapidly and the antioxidant enzyme activities decreased when beyond a certain light intensity threshold (at 120 d, the threshold was about 40 lx). The protective enzymes that played the major role under nighttime light stress were different among the three species. For H. paniculata, POD and CAT complemented each other to resist stress-induced oxidative damage, while the main enzyme of L. japonicum was POD. The biomass of the three species increased significantly under artificial light at night. H. paniculata was the most sensitive to nighttime light stress, while L. japonicum had the strongest resistance to the stress. The deciduous shrub H. paniculata could tolerate the white night light lower than 40 lx, while the evergreen shrubs P. fraseri and L. japonicum could tolerate the yellow night light lower than 40 lx.
Assuntos
Antioxidantes , Poluição Luminosa , Antioxidantes/metabolismo , Peroxidases/metabolismo , Peroxidases/farmacologia , Estresse Oxidativo , Peroxidase/metabolismo , Peroxidase/farmacologia , Plantas/metabolismo , Superóxido Dismutase/metabolismoRESUMO
Neuropathic pain (NP) is a chronic disease caused by damage to the peripheral or central nervous system. Connexin 43 (Cx43), the primary connexin expressed by astrocytes, has been reported to be significantly increased in NP. However, the roles and mechanisms of Cx43 in the development and maintenance of NP remain largely unknown, while microglia activation has been commonly regarded as a key factor of NP. In the present study, we found that Cx43 deletion significantly ameliorated spared nerve injury (SNI)-induced NP and suppressed SNI induced c-Fos expression in the spinal cord. Notably, Cx43 deletion led to much less SNI-induced microglia activation in the spinal cord. These results suggest that astrocyte Cx43 may play a significant role in regulating microglial activation and NP.
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Astrócitos , Conexina 43 , Neuralgia , Astrócitos/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Hiperalgesia/metabolismo , Microglia/metabolismo , Neuralgia/genética , Neuralgia/patologia , Medula Espinal/metabolismo , Animais , CamundongosRESUMO
This study aimed to evaluate the therapeutic effect of IR-61, a novel mitochondrial heptamethine cyanine dye with antioxidant effects, on diabetes mellitus-induced erectile dysfunction (DMED). Eight-week-old male Sprague-Dawley rats were intraperitoneally injected with streptozotocin (STZ) to induce type 1 diabetes. Eight weeks after STZ injection, all rats were divided into three groups: the control group, DM group, and DM + IR-61 group. In the DM + IR-61 group, the rats were administered IR-61 (1.6 mg kg-1) twice a week by intravenous injection. At week 13, erectile function was evaluated by determining the ratio of the maximal intracavernous pressure to mean arterial pressure, and the penises were then harvested for fluorescent imaging, transmission electron microscopy, histological examinations, and Western blot analysis. Whole-body imaging suggested that IR-61 was highly accumulated in the penis after intravenous injection. IR-61 treatment significantly improved the maximal ICP of diabetic rats. Additionally, IR-61 ameliorated diabetes-induced inflammation, apoptosis, and phenotypic transition of corpus cavernosum smooth muscle cells (CCSMCs) in penile tissue. IR-61 also attenuated mitochondrial damage, reduced reactive oxygen species production in the corpus cavernosum and upregulated sirtuin1 (SIRT1), sirtuin3 (SIRT3), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and heme oxygenase expression in penile tissue. In conclusion, IR-61 represents a potential therapeutic option for DMED by protecting the mitochondria of CCSMCs, which may be mediated by activation of the SIRT1, SIRT3, and Nrf2 pathways.
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Carbocianinas/farmacologia , Diabetes Mellitus Experimental/complicações , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/etiologia , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Heavy metal pollution is one of the thorniest issues in the world, which is a serious threat to ecosystems and food security. As an important link of food chain and food web in the ecosystem, herbivorous insects play important role in the transfer and accumulation of heavy metals. Consequently, more and more attentions have been paid on the potential effects of heavy metal pollution on herbivorous insects. Here, we reviewed the effects of heavy metal pollution on herbivorous insects with literature publshied during 2007 to 2018. Herbivorous insects were exposed to heavy metals pollution via four ways, including insect diets or food added with inorganic heavy metals, field exposure with heavy metals, "soil/substrate-plants-herbivorous insect" food chain and in vitro injection. Excessive accumulation of heavy metals in insect body results in decreased survival rate, reproductive capacity and population growth, the retarded growth and development. Physiological and biochemical toxicity of heavy metal pollution to herbivorous insects included cell ultra-structure destruction and DNA damage, decreased amount of energy materials, and changes in enzymes acti-vity and gene expression levels. However, herbivorous insects can resist heavy metal stress by producing metallothionein and enhancing activity of detoxification enzymes etc., which probably results in their adaptive evolution to heavy metal stress at low intensity or long-term and even improve their tolerance to other stresses (e.g., pesticides).
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Metais Pesados , Poluentes do Solo , Animais , Ecossistema , Poluição Ambiental , InsetosRESUMO
OBJECTIVE: To explore the clinical therapeutic effect and mechanism of acupuncture on headache in the recovery phase of ischemic stroke. METHODS: A total of 97 patients with headache in the recovery phase of ischemic stroke were randomized into an acupuncture group (57 cases) and a western medication group (40 cases). In the western medication group, flunarizine hydrochloride capsule was taken orally 5 mg each time, once a day. In the acupuncture group, acupuncture was applied at Qiuxu (GB 40), Zulinqi (GB 41), Xuanli (GB 6), Shuaigu (GB 8), Fengchi (GB 20) and Baihui (GV 20) for migraine; Chongyang (ST 42), Neiting (ST 44), Jiexi (ST 41), Zusanli (ST 36), Hegu (LI 4), Cuanzhu (BL 2) and Baihui (GV 20) for forehead pain; Jinggu (BL 64), Kunlun (BL 60), Tianzhu (BL 10), Fengchi (GB 20), Baihui (GV 20) and Sishencong (EX-HN 1) for occipital headache; Taichong (LR 3), Yongquan (KI 1), Sanyinjiao (SP 6), Fengchi (GB 20), Baihui (GV 20) and Sishencong (EX-HN 1) for parietal headache. The needles were retained for 30 min each time, once a day and 5 times a week. Both of the two groups were given consecutive treatment for 14 days. The visual analogue scale (VAS) and the headache scores before and after treatment and the recurrence rate 1 month after treatment were observed to evaluate the therapeutic effect, before and after treatment, the contents of substance P (SP), dopamine (DA), serotonin (5-HT), alpha-endorphin (α-EP) and beta-endorphin (ß-EP) in plasma were determined by ELISA in the two groups. RESULTS: Compared before treatment, the VAS scores, the headache scores and the contents of SP, DA and 5-HT in plasma were reduced and the contents ofα-EP andß-EP in plasma were increased in the two groups (all P<0.01). After treatment, the changes of the VAS score, the headache score and the contents of pain-related factors and endogenous opioid peptides in plasma in the acupuncture group were larger than the western medication group (all P<0.05). The total effective rate in the acupuncture group was 84.2% (48/57), which was superior to 62.5% (25/40) in the western medication group, and the recurrence rate in the acupuncture group was lower than the western medication group (both P<0.01). CONCLUSION: The therapeutic effect of acupuncture on headache in the recovery phase of ischemic stroke is superior to flunarizine hydrochloride capsule, and the mechanism may relate to down-regulate the pain-related factors and up-regulate endogenous opioid peptides in plasma.
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Terapia por Acupuntura , Cefaleia/terapia , Acidente Vascular Cerebral , Pontos de Acupuntura , Terapia por Acupuntura/métodos , Isquemia Encefálica , Flunarizina/uso terapêutico , Humanos , Acidente Vascular Cerebral/complicações , Resultado do Tratamento , Vasodilatadores/uso terapêuticoRESUMO
OBJECTIVE: A retrospective analysis of clinical characteristics and immunological manifestations of primary Sjogren's syndrome (pSS) patients with or without renal involvement was conducted in order to elucidate the potential risk factors of renal damage in pSS and evaluate the condition. METHODS: A total of 1002 patients, who fulfilled the 2002 classification criteria for pSS from the Second Affiliated Hospital of Shanxi Medical University, were enrolled in the cross-sectional study. Clinical, immunological, and histological characteristics were compared between pSS patients with and without renal involvement, and potential risk factors of renal involvements in pSS patients were examined by multivariate analysis. RESULTS: Among these pSS patients, there were 162 cases (16.17%) with and 840 cases (83.83%) without renal damage. Serious edema of both lower limbs, interstitial nephritis, and renal tubular acidosis were found in the pSS with renal damage group. Compared with simple pSS patients, the levels of creatinine, cystatin C, and alpha-1-microglobulin (α 1-MG) in the pSS with renal damage group were significantly increased. The difference between the two groups was statistically significant (P < 0.05). The AUC of the combination of creatinine and α 1-MG and creatinine, α 1-MG, and creatinine was statistically larger than that of creatinine, and the biomarker of the biggest AUC is the combination of creatinine and α 1-MG. CONCLUSION: The main clinical manifestations of pSS with renal damage were edema of the lower limbs, interstitial nephritis, and renal tubular acidosis. Creatinine and α 1-MG are effective indicators for renal function in pSS, which may provide a better understanding for clinical decision-making.
Assuntos
Acidose Tubular Renal/epidemiologia , Rim/patologia , Extremidade Inferior/patologia , Nefrite Intersticial/epidemiologia , Síndrome de Sjogren/epidemiologia , alfa-Globulinas/metabolismo , Biomarcadores/metabolismo , China/epidemiologia , Creatinina/sangue , Estudos Transversais , Edema , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de RiscoRESUMO
Intercropping is a sound eco-agriculture model, but aquatic crops (e.g., rice) intercropping is seldom researched. In the present study, rice and water spinach were chosen as the research objects, a field trial was conducted to explore the yields, interspecific relationship and Si, N nutrition of rice under rice-water spinach intercropping for four seasons during two consecutive years (2014-2015). The experiment had five treatments: rice monoculture, water spinach monoculture, and rice-water spinach intercropping ratios of 2:2, 3:2, 4:2, respectively. The results showed that rice-water spinach intercropping significantly increased rice yield, and the increase rates of 2:2, 3:2 and 4:2 intercropping per unit area were 77.5%-120.6%, 64.9%-80.9%, 37.7%-56.0%, respectively. However, intercropping resulted in reduction of water spinach yield. Intercropping significantly increased total yield of rice and water spinach from land equivalent ratios (LER) analysis. The values of LER were more than 1.0, and the ratio of 3:2 intercropping had the best effect. As for the competitive index, rice was more competitive than water spinach in intercropping system, especially in early season. Compared with rice monoculture, rice-water spinach intercropping significantly increased the absorption of Si and N in rice leaves, and Si content of rice leaves during ripening stage, but didn't increase its N content and even slightly reduced it during ripening stage. Intercropping had no significant effect on available Si, ammonium N and nitrate N content in soil. Compared with rice monoculture and intercropping, water spinach monoculture had always the highest available Si, ammonium N and nitrate N contents in soil through the experiment period. The results suggested that rice-spinach intercropping could promote rice to absorb silicon and nitrogen and increase the competitive ability of rice.
Assuntos
Ipomoea , Nitrogênio , Oryza , Agricultura , Produtos Agrícolas , SoloRESUMO
Greenhouse gases (GHGs) emission from arable field is a hot topic recently, adopting appropriate cropping systems is an effective way to reduce GHGs emission. This paper reviewed the impacts and mechanisms of intercropping on soil CO2 and N2O emissions in upland field. Rational intercropping systems could increase soil organic carbon (SOC), promote the transformation of straw to SOC, slow down mineralization rate of SOC, and hence reduce soil CO2 emissions. The Poaceae intercropping with legume could maintain the stability of yield while reducing synthetic N inputs, formation of inorganic N by residue decomposition and soil mineral N, and further reducing soil N2O emission. In addition, crop interactions in intercropping system and filed microclimate were important factors on GHGs emission as well. It is necessary to extent the period of researches in field GHGs emission in order to fully understand the underlying mechanisms of GHGs emission in farm land, especially the function of soil microorganisms at molecular level. It would provide theoretical knowledge in building environment-friendly agricultural system in the future.
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Agricultura/métodos , Dióxido de Carbono/análise , Óxido Nitroso/análise , Solo/química , Fabaceae/crescimento & desenvolvimento , Efeito Estufa , Nitrogênio/análise , Poaceae/crescimento & desenvolvimentoRESUMO
Bacillus thuringiensis (Bt) protein can enter the soil through Bt crops straw returning to field, which may affect the growth and reproduction of soil animals, such as earthworms. Here, Bt rice (b2B138) and conventional rice (Anfeng A) straw were returned in soil to evaluate the impact of Bt rice on Eisenia fetida. Two varieties of rice straw were added into soil to breed E. fetida at the rates of 2.5%, 5%, 7.5% and 10%. The survival rate, relative growth rate, reproduction of earthworm, the Cry1Ab content in soil-straw mixture and earthworm were detected after 7, 15, 30, 45, 60, 75, 90 d. The results showed that Bt rice straw returning at higher concentrations (7.5% and 10%) inhibited the survival rate of E. fetida. Bt rice straw returning had no adverse effect on relative growth rate (RGR) of E. fetida. Bt rice straw treatment improved the reproduction of earthworms under 5%, 7.5% and 10% straw returning in soil. Enzyme-linked immunosorbent assay (ELISA) results indicated that immunoreactive Cry1Ab was detectable in soil-straw mixture and E. fetida from Bt rice treatments, and a strong decline was observed in soil-straw mixture with the increase of treated time. Therefore, Cry1Ab released from Bt rice straw returning at 2.5% and 5% concentration had no adverse effects on the growth and reproduction of E. fetida.
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Oligoquetos/crescimento & desenvolvimento , Oryza , Solo , Animais , Bacillus thuringiensis , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/isolamento & purificação , Produtos Agrícolas , Endotoxinas/isolamento & purificação , Proteínas Hemolisinas/isolamento & purificação , Caules de Planta , Plantas Geneticamente Modificadas , ReproduçãoRESUMO
A series of novel 2-acyl-6-aryl substituted indolizine derivatives was synthesized by a novel tandem reaction between 4-acyl-pyrrole-2-carbaldehyde derivatives and ethyl 4-bromo-3-arylbut-2-enoate under mild conditions. The compounds were characterized using IR, (1)H NMR (13)C NMR and HRMS. The crystal structure of 7a was determined using single crystal X-ray crystallography. The absorption results showed that compounds 7a-e presented their absorption maxima at ca. 270 nm, while compounds 7f and 7g with a larger conjugation system exhibited red-shifted absorption character (ca. 280 nm). Fluorescence spectra revealed that these compounds exhibited blue fluorescence (434-456 nm) in dilute solutions and showed quantum yields of fluorescence between 0.02 and 0.39 in dichloromethane.
Assuntos
Indolizinas/química , Indolizinas/síntese química , Fenômenos Ópticos , Cristalografia por Raios X , Elétrons , Cloreto de Metileno/química , Conformação Molecular , Solventes/química , Espectrometria de Fluorescência , Espectrofotometria UltravioletaRESUMO
The spatiotemporal dynamics of Bt protein in soil and the change of soil nutrients in rhizosphere soil, root surface soil and soils at 0-20, 20-40 and 40-60 cm were measured in greenhouse experiments. Two Bt corns, 5422Bt1 and 5422CBCL, and their near isogenic non-Bt variety 5422 were grown for 90 days and the crop residues were retained to soil. Results showed that 1.59 and 2.78 ng x g(-1) Bt protein were detected in the rhizosphere soil with Bt corns 5422Bt1 and 5422CBCL immediately after harvest. However, there were only trace amounts of Bt protein (< 0.5 ng x g(-1)) were detected in root surface soil after 90 days and in bulk soil in the two Bt corn treatments after 30, 60 and 90 days. When corn residues returned to soil, Bt protein declined rapidly within 3 days and only trace amounts of Bt protein were measured after 7 days. There were no sig- nificant differences in organic matter, available nutrient (alkaline hydrolytic N, available P, available K) or total nutrient (total N, total P, total K) in root surface soils and soils at 0-20 cm, 20-40 cm and 40-60 cm among the Bt and non-Bt corns after 90 days. Sixty days after returning crop residues of 5422Btl to soil, the contents of organic matter and total N increased and the content of available K reduced significantly in the 0-20 cm soil depth. There were no significant differences in any other parameter at the 0-20 cm depth, neither for any parameter in the 20-40 cm and 40-60 cm soil depths compared to those in the non-Bt corn 5422 treatment. There were no significant differences in soil nutrient contents in Bt corn 5422CBCL treatment compared to those in non-Bt corn 5422 treatment except that available phosphorus content was reduced in root surface soils, and total P content increased at the 0-20 cm soil depth after 90 days. When crop residues of Bt corn 5422 CBCL were returned to soil, only available P content in the 0-20 cm soil layer was evidently higher compared to the soil receiving crop residues of non-Bt corn 5422. Results suggested that Bt protein released from root and crop residues of Bt corns would not accumulate in soil, and growing Bt corns and returning crop residues to soil would have no significant effect on soil nutrients in general.
Assuntos
Proteínas de Bactérias/química , Endotoxinas/química , Proteínas Hemolisinas/química , Plantas Geneticamente Modificadas/química , Rizosfera , Solo/química , Zea mays/química , Toxinas de Bacillus thuringiensis , Nitrogênio/química , Fósforo/química , Raízes de Plantas , Potássio/química , Zea mays/genéticaRESUMO
Chemical composition, antimicrobial and antioxidant activities of the essential oil of Ampelopsis megalophylla were evaluated in this research. GC-MS analysis of the essential oil revealed 42 compounds, representing 88.54% of the oil. The major compounds were borneol (10.81%), α-pinene (6.74%) and ß-elemene (6.23%). The antimicrobial activity of the essential oil was evaluated against 13 micro-organisms using the disc diffusion and broth microdilution methods. Results demonstrated higher effects of this oil against Gram-positive bacteria than the other reference strains tested. The antioxidant effect of the essential oil was evaluated by using 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,20-azinobis-3-ethylbenzthiazoline-6-sulfonate scavenging assays. The essential oil exhibited moderate antioxidant activity.
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Ampelopsis/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Óleos Voláteis/química , Óleos de Plantas/química , Antibacterianos/química , Antioxidantes/química , Monoterpenos Bicíclicos , Compostos de Bifenilo/farmacologia , Canfanos/química , Canfanos/isolamento & purificação , Canfanos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Picratos/farmacologia , Folhas de Planta/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologiaRESUMO
A series of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(3-butyl-1-chloroimidazo[1,5-a]- pyridin-7-yl)-1,3,4-oxadiazole derivatives has been synthesized from 3-butyl-1-chloroimidazo[1,5-a]pyridine-7-carboxylic acid and ethyl 3-aryl-1H-pyrazole-5-carboxylate. The compounds were characterized using IR, (1)H NMR, HRMS and UV-vis absorption. The fluorescence spectral characteristics of the compounds in dichloromethane were investigated. The results showed that absorption λmax and emission λmax was less correlated with substituent groups on N-1 position of pyrazole moiety and para position of benzene moiety. The calculated molecular orbital correlates well with their absorption.
Assuntos
Oxidiazóis/química , Pirazóis/química , Cristalografia por Raios X , Halogenação , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Oxidiazóis/síntese química , Pirazóis/síntese química , Piridinas/síntese química , Piridinas/química , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
A series of novel imidazo[1,5-a]pyridine-hydrazone derivatives were synthesized and characterized by infrared spectroscopy (IR), 1H NMR, 13C NMR and high resolution mass spectrometer (HRMS). Typically, the spatial structure of compound 3j was determined using X-ray diffraction analysis. The UV-vis absorption and fluorescence spectral characteristics of the compounds in dichloromethane and acetonitrile were investigated. Absorption peaks could be observed in the wavelength range 290-450 nm. It can also be seen that they display very similar maximum emission. The group attached to hydrazone hardly influenced the maximum emission. Furthermore, all the compounds were evaluated for antibacterial activity and were found to be more effective against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa and Shigella compared with chloramphenicol.
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Antibacterianos/síntese química , Antibacterianos/farmacologia , Hidrazonas/química , Piridinas/química , Antibacterianos/química , Bactérias/efeitos dos fármacos , Cristalografia por Raios X , Hidrazonas/farmacologia , Estrutura Molecular , Piridinas/farmacologiaRESUMO
Three series of organoboron-based molecules, including biphenyls 1a-c, diphenylacetylenes 2a-c, and stilbenes 3a-c, in which the electron-accepting boryl and the electron-donating amino groups are introduced at different positions, have been comprehensively investigated to explore the effect of the substitution pattern on the intramolecular charge-transfer emissions. In cyclohexane solution, the change of substitution pattern from p,p' to o,p' by introduction of boryl at the lateral o-position rather than the terminal p-position leads to bathochromism in the absorption and emission spectra. With further variation of the amino position from the terminal p'-position in o,p'-substitution to the lateral o'-position in an o,o'-substitution pattern, a blueshift was observed in the absorption owing to the less-efficient conjugation extension of the amino group as the result of sp(3) hybridization. It is notable that the emission of the three series of molecules changes with completely different trends. Only the emission of the biphenyl is redshifted further from o,p'-substituted 1b to o,o'-substituted 1a, whereas o,o'-substituted diphenylacetylene 2a maintains almost the same spectrum as that of o,p'-substituted diphenylacetylene 2b and the fluorescence of o,o'-substituted stilbene 3a is even blueshifted compared with o,p'-substituted stilbene 3b. As a result, the o,o'-substituted biphenyl 1a shows the longest emission wavelength despite the limited conjugation of the parent biphenyl skeleton. The long emission wavelength of 1a may arise from its extremely twisted structure, which would cause a significant structural relaxation in the exited state. In the solid state, 1a still keeps almost the longest emission wavelength. In addition, its quantum yield is also among the highest. The unusual properties, intense solid-state emission together with long emission wavelength, and particularly large Stokes shift, which are difficult to attain by structural modification of other parent π-conjugated frameworks, have been achieved by the introduction of boryl and amino groups at the o,o'-positions of the biphenyl skeleton.
RESUMO
KEY MESSAGE: BjYSL7 encodes a plasma-localized metal-NA transporter and has transport Fe(II)-NA complexes activity. BjYSL7 is involved in the transport of Cd and Ni from roots to shoots. Heavy metal transporters play a key role in regulating metal accumulation and transport in plants. In this study, we isolated a novel member of the yellow stripe-like (YSL) gene family BjYSL7 from the hyperaccumulator Brassica juncea. BjYSL7 is composed of 688 amino acids with 12 putative transmembrane domains and is over 90 % identical to TcYSL7 and AtYSL7. Real-time PCR analysis revealed that BjYSL7 mRNA was mainly expressed in the stem under normal condition. The expression of BjYSL7 was found to be up-regulated by 127.1-, 12.7-, and 3.4-fold in roots and 6.5-, 4.3-, and 2.8-fold in shoots under FeSO4, NiCl2, and CdCl2 stresses, respectively. We have demonstrated that BjYSL7 is a Fe(II)-NA influx transporter by yeast functional complementation. Moreover, a BjYSL7::enhanced green fluorescent protein (EGFP) fusion localized to the plasma membrane of onion epidermal cells. The BjYSL7-overexpressing transgenic tobacco plants exhibited longer root lengths, lower relative inhibition rate of lengths and superior root hair development compared to that of wild-type (WT) plants in the presence of CdCl2 and NiCl2. Furthermore, the concentrations of Cd and Ni in shoots of BjYSL7-overexpressing plants are significantly higher than that of WT plants. Compared with WT plants, BjYSL7-overexpressing plants exhibited Fe concentrations that were higher in the shoots and seeds and lower in the roots. Taken together, these results suggest that BjYSL7 might be involved in the transport of Fe, Cd and Ni to the shoot and improving heavy metal resistance in plants.
Assuntos
Metais Pesados/toxicidade , Mostardeira/genética , Nicotiana/genética , Nicotiana/metabolismo , Proteínas de Plantas/genética , Transporte Biológico/genética , Cádmio/farmacocinética , Membrana Celular , Clonagem Molecular , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ferro/farmacocinética , Metais Pesados/farmacocinética , Níquel/farmacocinética , Cebolas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Estresse Fisiológico/genética , Nicotiana/efeitos dos fármacosRESUMO
A series of novel 5-aryl-3-benzimidazolyl-1-phenyl-pyrazoline derivatives were synthesized by the reaction of benzimidazolyl chalcone and phenylhydrazine in 41-72% yields. The compounds were characterized using IR, (1)H NMR and HRMS. Absorption and fluorescence spectra were measured in different organic solvent. An intense absorption maxima was noted at ca. 370 nm and emission maxima was noted at ca. 460 nm. The absorption spectra of the pyrazoline derivatives reveal that 5-aryl group attached to the pyrazoline ring hardly influenced the maximum absorption. The fluorescence spectra of these compounds indicated the emission wavelength was red shifted and the fluorescence intensity was decreased with the increase in solvent polarity.
Assuntos
Benzimidazóis/química , Pirazóis/química , Benzimidazóis/síntese química , Chalconas/síntese química , Chalconas/química , Espectroscopia de Ressonância Magnética , Fenil-Hidrazinas/síntese química , Fenil-Hidrazinas/química , Pirazóis/síntese química , Espectrometria de Fluorescência , Espectrofotometria UltravioletaRESUMO
Standard artificial diet was added with different concentration lead (Pb) to feed herbivorous insect Spodoptera litura larvae to study their growth and reproduction under the effects of Pb stress. With the increasing concentration Pb in the diet, the survival rate and body mass of the larvae at their different development stages (larvae, pupae, and adults) decreased. The minimum concentration of Pb which caused the significant decrease of the survival rate was 100 mg x kg(-1), and that caused a remarkable decrease of body mass was 50 mg x kg(-1). After fed with the diet containing 25-200 mg x kg(-1) of Pb, the duration of laying eggs was significantly shortened. With increasing concentration Pb in the diet, the oviposition rate and fecundity of female adults decreased significantly, the average mass of one thousand eggs was significantly less than that of the control, and the hatching rate of the eggs laid by adults was also decreased significantly. All the results suggested that Pb stress had significant inhibition effects on the growth and reproduction of S. litura.