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1.
J Asian Nat Prod Res ; 26(7): 773-779, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38469752

RESUMO

Phytochemical study on 90% ethanol extract from the green walnut husks of Juglans mandshurica Maxim. resulted into the isolation of three undescribed triterpenoids, juglansmanoids A-C (1-3). Structural elucidation of all the compounds were performed by spectral methods such as 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated components were evaluated in vitro for anti-hyaluronidase activities. As a result, triterpenoid 1 exhibited potent anti-hyaluronidase activity (IC50 = 9.78 µg/ml) three times more than the positive control drug oleanolic acid (IC50 = 40.12 µg/ml).


Assuntos
Hialuronoglucosaminidase , Juglans , Triterpenos , Juglans/química , Triterpenos/farmacologia , Triterpenos/química , Triterpenos/isolamento & purificação , Estrutura Molecular , Hialuronoglucosaminidase/antagonistas & inibidores , Ressonância Magnética Nuclear Biomolecular
2.
Mar Pollut Bull ; 187: 114521, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36621299

RESUMO

Human vibriosis, caused by pathogenic Vibrio spp., such as Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus, has been increasing worldwide, mediated by increasing consumption of seafood. The present study was conducted to examine the global prevalence of V. vulnificus, V. parahaemolyticus and V. cholerae in fishes. We searched PubMed, Web of Science, Scopus, and CNKI for peer-reviewed articles and dissertations prior to December 31, 2021. A total of 24,831 articles were retrieved, and 82 articles contained 61 fish families were included. The global pooled prevalence of V. cholerae, V. parahaemolyticus and V. vulnificus in fishes was 9.56 % (95 % CI: 2.12-20.92), 24.77 % (95 % CI: 17.40-32.93) and 5.29 % (95 % CI: 0.38-13.61), respectively. Subgroup and meta-regression analyses showed that study-level covariates, including temperature, country, continent, origin and detection methods partly explained the between-study heterogeneity. These heterogeneities were underpinned by differences of the three Vibrio spp. in fishes at geographical and climatic scales. These results reveal a high global prevalence of pathogenic Vibrio spp. in fishes and highlight the need for implementation of more effective prevention and control measures to reduce food-borne infection in humans.


Assuntos
Vibrioses , Vibrio cholerae , Vibrio parahaemolyticus , Vibrio , Animais , Humanos , Saúde Pública , Prevalência , Alimentos Marinhos , Vibrioses/epidemiologia , Vibrioses/veterinária , Peixes
3.
ACS Appl Mater Interfaces ; 14(5): 7030-7038, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35084812

RESUMO

Microwave dielectric ceramics exhibiting a low dielectric constant (εr), high quality factor (Q × f), and thermal stability, specifically in an ultrawide temperature range (from -40 to +120 °C), have attracted much attention. In addition, the development of 5G communication has caused an urgent demand for electronic devices, such as dielectric resonant antennas. Hence, the feasibility of optimizing the dielectric properties of the SmNbO4 (SN) ceramics by substituting Bi3+ ions at the A site was studied. The permittivity principally hinges on the contribution of Sm/Bi-O to phonon absorption in the microwave range, while the reduced sintering temperature results in a smaller grain size and slightly lower Q × f value. The expanded and distorted crystal cell indicates that Bi3+ doping effectively regulates the temperature coefficient of resonant frequency (TCF) by adjusting the strains (causing the distorted monoclinic structure) of monoclinic fergusonite besides correlating with the permittivity. Moreover, a larger A-site radius facilitates the acquisition of near-zero TCF values. Notably, the (Sm0.875Bi0.125)NbO4 (SB0.125N) ceramic with εr ≈ 21.9, Q × f ≈ 38 300 GHz (at ∼8.0 GHz), and two different near-zero TCF values of -9.0 (from -40 to +60 °C) and -6.6 ppm/°C (from +60 to +120 °C), respectively, were obtained in the microwave band. A simultaneous increase in the phase transition temperature (Tc) and coefficients of thermal expansion (CTEs) by A-site substitution provides the possibility for promising thermal barrier coating (TBC) materials. Then, a cylindrical dielectric resonator antenna (CDRA) with a resonance at 4.86 GHz and bandwidth of 870 MHz was fabricated by the SB0.125N specimen. The exceptional performance shows that the SB0.125N material is a possible candidate for the sub-6 GHz antenna owing to the advantages of low loss and stable temperature.

4.
Sci Total Environ ; 806(Pt 2): 150562, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34852432

RESUMO

The aim of this review is to identify the worldwide trend of waterborne protozoan outbreaks and how it varies between geographic regions during the period from 2017 to 2020. Data about waterborne protozoan outbreaks were gathered and stratified by continent, country, water source, and protozoan species associated with the outbreak. The highest prevalence of waterborne protozoan outbreaks was reported in developed countries. Out of 251 outbreaks reported worldwide during the studied period, 141, 51 and 24 outbreaks were recorded in the USA, UK, and New Zealand, respectively. These outbreaks were mainly associated with Cryptosporidium (192 outbreaks) and Giardia (48 outbreaks). Cyclospora cayetanensis, Dientamoebafragilis and Toxoplasma gondii were associated with 7 outbreaks. One outbreak was associated with each of Blastocystis hominis, Entamoeba histolytica, Microsporidia or Naegleria fowleri. This data suggests large discrepancies in the number of outbreaks reported between geographic regions, with most outbreaks recorded in developed countries. Differences in the prevalence of outbreaks between countries are likely attributed to the availability of diagnostic capabilities and surveillance programs to monitor water contamination with pathogenic protozoa. More attention and concerted efforts are required to improve water safety and to alleviate the impact of waterborne protozoan infections. Appropriate surveillance of water contamination with protozoa can enable public health officials to identify source of contamination and implement the necessary measures to limit transmission and prevent outbreaks.


Assuntos
Criptosporidiose , Cryptosporidium , Giardíase , Criptosporidiose/epidemiologia , Surtos de Doenças , Giardíase/epidemiologia , Humanos , Prevalência
5.
J Neurosci ; 41(48): 9988-10003, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34642215

RESUMO

Long-term limb nerve injury often leads to mirror-image pain (MIP), an abnormal pain sensation in the limb contralateral to the injury. Although it is clear that MIP is mediated in part by central nociception processing, the underlying mechanisms remain poorly understood. The anterior cingulate cortex (ACC) is a key brain region that receives relayed peripheral nociceptive information from the contralateral limb. In this study, we induced MIP in male mice, in which a unilateral chronic constrictive injury of the sciatic nerve (CCI) induced a decreased nociceptive threshold in both hind limbs and an increased number of c-Fos-expressing neurons in the ACC both contralateral and ipsilateral to the injured limb. Using viral-mediated projection mapping, we observed that a portion of ACC neurons formed monosynaptic connections with contralateral ACC neurons. Furthermore, the number of cross-callosal projection ACC neurons that exhibited c-Fos signal was increased in MIP-expressing mice, suggesting enhanced transmission between ACC neurons of the two hemispheres. Moreover, selective inhibition of the cross-callosal projection ACC neurons contralateral to the injured limb normalized the nociceptive sensation of the uninjured limb without affecting the increased nociceptive sensation of the injured limb in CCI mice. In contrast, inhibition of the non-cross-callosal projection ACC neurons contralateral to the injury normalized the nociceptive sensation of the injured limb without affecting the MIP exhibited in the uninjured limb. These results reveal a circuit mechanism, namely, the cross-callosal projection of ACC between two hemispheres, that contributes to MIP and possibly other forms of contralateral migration of pain sensation.SIGNIFICANCE STATEMENT Mirror-image pain (MIP) refers to the increased pain sensitivity of the contralateral body part in patients with chronic pain. This pathology requires central processing, yet the mechanisms are less known. Here, we demonstrate that the cross-callosal projection neurons in the anterior cingulate cortex (ACC) contralateral to the injury contribute to MIP exhibited in the uninjured limb, but do not affect nociceptive sensation of the injured limb. In contrast, the non-cross-callosal projection neurons in the ACC contralateral to the injury contribute to nociceptive sensation of the injured limb, but do not affect MIP exhibited in the uninjured limb. Our study depicts a novel cross-callosal projection of ACC that contributes to MIP, providing a central mechanism for MIP in chronic pain state.


Assuntos
Lateralidade Funcional/fisiologia , Giro do Cíngulo/fisiopatologia , Neuralgia/fisiopatologia , Traumatismos dos Nervos Periféricos/fisiopatologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neuralgia/etiologia
6.
ACS Appl Mater Interfaces ; 13(15): 17817-17826, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33835792

RESUMO

Structure and dielectric properties of gillespite-type ceramics ACuSi4O10 (A = Ca, Sr, Ba) were investigated by crystal structure refinement, far-infrared reflectivity spectroscopy, and microwave dielectric measurements. A series of (CaxSr1-x)CuSi4O10 (0 < x < 1) ceramics with relative permittivities of 5.70-5.82, Q × f values of 20391-48794 GHz (@ ∼ 13.5 GHz), and τf of -46.3 to -38.9 ppm/°C were synthesized. By Ca2+ substitution for Sr2+ at the A-site, the rigid double-layered copper silicate framework remains stable, resulting in the nearly unchanged relative permittivity, while the [(Ca,Sr)O8] dodecahedron undergoes shrinkage and distortion, which is correlated to the changes in the Q × f and τf values. The normalized bond valence sums indicate that almost all ions are rattling, weakening the bond strengths and enlarging the molecular dielectric polarizability. The fitting of far-infrared reflectivity spectra reveals that the local structure changes suppress the intermediate and low-frequency vibrational modes significantly and improves the contribution from electronic polarization to permittivity. Symmetry breaking of the [(Ca,Sr)O8] dodecahedron conforms to the elevated restoring forces acting on the ions and improves the τf value. The large span in Q × f value may have intricate correlations to local structure changes and defects. Machine learning methods were introduced to explore the decisive structural factors for the Q × f value. A Q × f value prediction model correlated with the A-O2 bond length and the variance of A-O bond lengths was established. The Q × f values of isostructural (BaySr1-y)CuSi4O10 ceramics were predicted and verified by experiments.

7.
Huan Jing Ke Xue ; 41(10): 4653-4660, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124398

RESUMO

A rapid start of the completely autotrophic nitrogen removal over nitrite (CANON) process based on granular sludge and efficient nitrogen removal under mixotrophic conditions are important steps in a continuous flow reactor for CANON engineering applications. In this study, an aged CANON granular sludge was mechanically crushed to 0.3 mm as inoculum in an airlift internal-loop reactor (AIR) to achieve simultaneous COD removal and mixotrophic denitrification of the single-stage granular sludge. The system achieved stable partial nitrification by controlling DO after 26 days of startup. Granulation and anaerobic ammonia oxidation were then promoted by shortening the HRT to increase the ammonia nitrogen load to 5.65 kg ·(m3 ·d)-1. The total nitrogen removal rate reached 58% on the 68th day. Subsequently, the C/N ratio of influent was increased from 0 to 0.25 and 0.5, which promoted the synergistic growth of AOB, AMX, and heterotrophic microorganisms. The removal rates of ammonia and total nitrogen were 95% and 85% respectively, and the removal of COD reached approximately 80%. The activity of NOB such as Nitrospira was effectively inhibited as the COD concentration was increased. q(NH4+-N) and q(TN) were stable at 0.4 g ·(g ·h)-1 and 0.34 g ·(g ·h)-1, respectively, while q(NO3--N) was approximately 0.02 g ·(g ·h)-1. Microbial diversity was observed using MiSeq high-throughput sequencing. It showed that organic carbon had no significant effect on the abundance of Nitrosomomas and Candidutus_Kuenenia, while increasing the abundance of Candidutus_Brocadia and Denitratisoma in the sludge. This study provides ideas for the rapid start of continuous flow CANON granular sludge process to treat wastewater with low C/N ratio.


Assuntos
Nitrogênio , Esgotos , Processos Autotróficos , Reatores Biológicos , Desnitrificação , Nitritos , Oxirredução
8.
Dose Response ; 18(3): 1559325820950102, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922228

RESUMO

BACKGROUND: Post-stroke cognitive impairment (PSCI) is commonest clinical disorder in which peripheral cholinergic activity is important. Oleuropein (OLP) is polyphenol is present in olive oil. Here we evaluated the effect of OLP in cognitive dysfunction rats in post cerebral stroke model. METHODS: The post cerebral stroke cognitive dysfunction PSD rat model was created by occlusion of transient middle cerebral artery. The rats were divided into 6 groups named, Sham + Vehicle, Sham + OLP (50 mg/kg), PSD rats + Vehicle, PSD rats + OLP (20, 50 or 100 mg/kg). The spatial learning was assessed by Morris water maze (MWM). The expression of choline acetyltransferase (ChAT), acetylcholine (ACH), extent of histone acetylation and phosphorylation of cAMP response element-binding protein (CREB) were evaluated by Western blot assay and immunofluorescence staining. RESULTS: Treatment of OLP at various doses showed higher number of spontaneous and rewarded alterations and lesser percentage bias compared to vehicle treated PSD rats. OLP resulted in decreased levels of ChAT and ACH, whereas the degree of histone acetylation and phosphorylation of CREB improved in dose dependent pattern. CONCLUSION: treatment of OLP improved PSCI via increasing the phosphorylation of CREB and histone acetylation, thus attenuating cholinergic activity.

9.
Front Plant Sci ; 11: 1241, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903421

RESUMO

Cold damage has negatively impacted the yield, growth and quality of the edible cooking oil in Northern China and Brassica napus L.(rapeseed) planting areas decreased because of cold damage. In the present study we analyzed two Brassica napus cultivars of 16NTS309 (highly resistant to cold damage) and Tianyou2238 (cold sensitive) from Gansu Province, China using physiological, biochemical and cytological methods to investigate the plant's response to cold stress. The results showed that cold stress caused seedling dehydration, and the contents of malondialdehyde (MDA), relative electrolyte leakage and O2 - and H2O2 were increased in Tianyou2238 than 16NTS309 under cold stress at 4°C for 48 h, as well as the proline, soluble protein and soluble sugars markedly accumulated, and antioxidant enzymes of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) were higher in 16NTS309 compared with in Tianyou2238, which play key roles in prevention of cell damage. After exposure to cold stress, the accumulation of the blue formazan precipitate and reddish brown precipitate indicated that O2 - and H2O2, respectively, were produced in the root, stem, and leaf were higher than under non-cold conditions. Contents of O2 - and H2O2 in cultivar Tianyou2238 were higher than 16NTS309, this is consistent with the phenotypic result. To understand the specific distribution of O2 - in the sub-cellular, we found that in both cultivars O2 - signals were distributed mainly in cambium tissue, meristematic cells, mesophyll cytoplasm, and surrounding the cell walls of root, stem, leaves, and leaf vein by morphoanatomical analysis, but the quantities varied. Cold stress also triggered obvious ultrastructural alterations in leaf mesophyll of Tianyou2238 including the damage of membrane system, destruction of chloroplast and swelling of mitochondria. This study are useful to provide new insights about the physiological and biochemical mechanisms and cytology associated with the response of B. napus to cold stress for use in breeding cold-resistant varieties.

10.
Huan Jing Ke Xue ; 41(4): 1794-1800, 2020 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608687

RESUMO

The effects of different hydraulic retention time (HRT) on short-cut nitrification granular sludge were studied in a continuous stirred-tank reactor (CSTR) by maintaining stable influent ammonia nitrogen load. Particle size distribution, extracellular polymeric substances (EPS), and functional bacterial kinetics were analyzed. The morphology of granular sludge, the performance of the CSTR, and the activity of functional microorganisms were investigated. The high throughout sequencing technology of MiSeq was employed to analyze the structure of the microbial community in sludge. The results showed that the ammonia nitrogen removal rate in the reactor was gradually increased from 80% to 95%, and the nitrite accumulation rate was always over 85% when the HRT was decreased from 4 h to 1 h. Particle size distribution of granular sludge was greatly influenced by HRT. The mass fraction of granules with a diameter smaller than 0.3 mm and larger than 1.6 mm was gradually declined, whereas the mass fraction of granules with a diameter between 0.3 mm and 0.8 mm was increased when HRT was shortened from 4 h to 1 h. The dominating proportion of granules with a diameter between 0.3 mm and 0.8 mm reached about 50% when HRT was 1 h. The impact of HRT on the activity of functional microorganisms was studied, and HRT activity was found to be closely related to the size of granular sludge. Proteobacteria were dominant in the system. AOB enrichment was represented by Nitrosomonas, which was more than 56%. Shortening HRT is beneficial for the enrichment of AOB.

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