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1.
Calcif Tissue Int ; 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35048133

RESUMO

Osteoporosis-related bone defects are a major public health concern. Considering poor effects of a singular pharmacological treatment, many have sought combination therapies, including local treatment combined with systemic intervention. Based on recent evidence that selenium and silibinin increase bone formation and bone mineral density, it is hypothesized that systemic administration with silibinin plus local treatment with selenium may have an additive effect on bone regeneration in an OVX rat model with bone defects. To verify this hypothesis, 3-month-old ovariectomized Sprague- Dawley rats (n = 10/gp) were intraperitoneally with a dose of 50 mg/kg silibinin with selenium hydrogel scaffolds implanted into femoral metaphysis bone defect. Moreover, the MC3T3-E1 cells were co-cultured with selenium and silibinin, and observed any change of cell viability, ROS, and osteogenic activity. Experiment results show that the cell mineralization and osteogenic activity of silibinin plus selenium (SSe) group is enormously higher than the control (Con) group and selenium (Se) group, while ROS appears to be immensely reduced. Osteogenic protein expressions such as SIRT1, SOD2, RUNX-2 and OC of SSe group are significantly higher than Con group and Se group. Micro-CT and Histological analysis evaluation display that group SSe, compared with Con group and Se group, presents the strongest effect on bone regeneration, bone mineralization and higher expression of SIRT1 and SOD2. RT-qPCR analysis indicates that SSe group manifests increased SIRT1, SOD1, SOD2 and CAT than the Con group and Se group (p < 0.05). Our current study demonstrates that systemic administration with SIL plus local treatment with Se is a scheme for rapid repair of femoral condylar defects, and these effects may be achieved via reducing the oxidative stress pathway.

2.
Dalton Trans ; 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34989735

RESUMO

Electrocatalytic water oxidation is a rate-determining step in the water splitting process; however, its efficiency is significantly hampered by the limitations of cost-effective electrocatalysts. Here, an advanced Co(OH)2 electrocatalyst with ultralow iridium (Ir) doping is developed to enable outstanding oxygen evolution reaction (OER) properties; that is, in a 1 M KOH medium, an overpotential of only 262 mV is required to achieve a current density of 10 mA cm-2, and a small Tafel slope of 66.9 mV dec-1 is achieved, which is markedly superior to that of the commercial IrO2 catalyst (301 mV@10 mA cm-2; 66.9 mV dec-1). Through the combination of experimental data and a mechanism study, it is disclosed that the high intrinsic OER activity results from the synergistic electron coupling of oxidized Ir and Co(OH)2, which significantly moderate the adsorption energy of the intermediates. Moreover, we have also synthesized Ru-Co(OH)2 nanosheets and demonstrated the universal syntheses of Ir-doped CoM (M = Ni, Fe, Mn, and Zn) layered double hydroxides (LDHs).

3.
J Aerosol Sci ; 162: 105943, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35034977

RESUMO

Social distance will remain the key measure to contain COVID-19 before the global widespread vaccination coverage expected in 2024. Containing the virus outbreak in the office is prioritised to relieve socio-economic burdens caused by COVID-19 and potential pandemics in the future. However, "what is the transmissible distance of SARS-CoV-2" and "what are the appropriate ventilation rates in the office" have been under debate. Without quantitative evaluation of the infection risk, some studies challenged the current social distance policies of 1-2 m adopted by most countries and suggested that longer social distance rule is required as the maximum transmission distance of cough ejected droplets could reach 3-10 m. With the emergence of virus variants such as the Delta variant, the applicability of previous social distance rules are also in doubt. To address the above problem, this study conducted transient Computational Fluid Dynamics (CFD) simulations to evaluate the infection risks under calm and wind scenarios. The calculated Social Distance Index (SDI) indicates that lower humidity leads to a higher infection risk due to weaker evaporation. The infection risk in office was found more sensitive to social distance than ventilation rate. In standard ventilation conditions, social distance of 1.7 m-1.8 m is sufficient distances to reach low probability of infection (PI) target in a calm scenario when coughing is the dominant transmission route. However in the wind scenario (0.25 m/s indoor wind), distance of 2.8 m is required to contain the wild virus type and 3 m is insufficient to contain the spread of the Delta variant. The numerical methods developed in this study provide a framework to evaluate the COVID-19 infection risk in indoor environment. The predicted PI will be beneficial for governments and regulators to make appropriate social-distance and ventilation rules in the office.

4.
Eur J Med Chem ; 227: 113937, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34710744

RESUMO

Evodiamine and rutaecarpine are two alkaloids isolated from traditional Chinese herbal medicine Evodia rutaecarpa, which have been reported to have various biological activities in past decades. To explore the potential applications for evodiamine and rutaecarpine alkaloids and their derivatives, various kinds of evodiamine and rutaecarpine derivatives were designed and synthesized. Their antifungal profile against six phytopathogenic fungi Rhizoctonia solani, Botrytis cinerea, Fusarium graminearum, Fusarium oxysporum, Sclerotinia sclerotiorum, and Magnaporthe oryzae were evaluated for the first time. Furthermore, a series of modified imidazole derivatives of rutaecarpine were synthesized to investigate the structure-activity relationship. The results of antifungal activities in vitro showed that imidazole derivative of rutaecarpine A1 exhibited broad-spectrum inhibitory activities against R. solani, B. cinerea, F. oxysporum, S. sclerotiorum, M. oryzae and F. graminearum with EC50 values of 1.97, 5.97, 12.72, 2.87 and 16.58 µg/mL, respectively. Preliminary mechanistic studies showed that compound A1 might cause mycelial abnormalities of S. sclerotiorum, mitochondrial distortion and swelling, and inhibition of sclerotia formation and germination. Moreover, the curative effects of compound A1 were 94.7%, 81.5%, 80.8%, 65.0% at 400, 200, 100, 50 µg/mL in vivo experiments, which was far more effective than the positive control azoxystrobin. Significantly, no phytotoxicity of compound A1 on oilseed rape leaves was observed obviously even at a high concentration of 400 µg/mL. Therefore, compound A1 is expected to be a novel leading structure for the development of new antifungal agents.

5.
Chemosphere ; 287(Pt 2): 132113, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34826891

RESUMO

With rising concerns in the practical application of biochar for the remediation of environment influenced by various organic contaminants, a critical review to facilitate insights the crucial role that biochar has played in wastewater and polluted soil decontamination is urgently needed. This research therefore aimed to describe different intriguing dimensions of biochar interactions with organic contaminants, which including: (i) an introduction of biochar preparation and the related physicochemical properties, (ii) an overview of mechanisms and factors controlling the adsorption of organic contaminants onto biochar, and (iii) a summary of the challenges and an outlook of the further research needs in this issue. In the light of the survey consequences, the appearance of biochar indicates the potential in substituting the existing costly adsorbents, and it has been proved that biochar is one promising adsorbent for organic pollutants adsorption removal from water and soil. However, some research gaps, such as dynamic adsorption, potential environmental risks, interactions between biochar and soil microbes, novel modification techniques, need to be further investigated to facilitate its practical application. This research will be conductive to better understanding the adsorption removal of organic contaminants by biochar.


Assuntos
Carvão Vegetal , Poluentes do Solo , Adsorção , Solo , Poluentes do Solo/análise
6.
Neurosci Res ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34861294

RESUMO

Synaptic transmission via neurochemical release is the fundamental process that integrates and relays encoded information in the brain to regulate physiological function, cognition, and emotion. To unravel the biochemical, biophysical, and computational mechanisms of signal processing, one needs to precisely measure the neurochemical release dynamics with molecular and cell-type specificity and high resolution. Here we reviewed the development of analytical, electrochemical, and fluorescence imaging approaches to detect neurotransmitter and neuromodulator release. We discussed the advantages and practicality in implementation of each technology for ease-of-use, flexibility for multimodal studies, and challenges for future optimization. We hope this review will provide a versatile guide for tool engineering and applications for recording neurochemical release.

7.
Comput Biol Med ; 141: 105129, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34915333

RESUMO

In this study, we present a detailed flow analysis using an anatomically accurate rat nasal cavity model, in which the anatomy and physiology of the nasal airway was thoroughly examined. Special efforts were given to the swirling flow structures in the nasal vestibule (anterior section of the nose, lined by squamous epithelium), fractional flow patterns in the olfactory (posterior superior section of the rat nose, lined by olfactory epithelium), and a designated method to precisely quantify flow apportionment in the olfactory region was developed. Results revealed distinct inspiratory flow patterns in the anterior vestibule region, where the accelerated airflow undergoes two sharp turns as traveling through the tortuous airway, making a route in a shape of 8. Besides this, exceptionally large flow apportionment was observed at the interface of the olfactory recess, which can be as much as 15 times greater than that in the human nose. The thorough understanding of the airflow dynamics in the rat nasal cavity is necessary to avoid potential misinterpretation of rat-derived inhalation toxicity results. Research findings are expected to play a fundamental role in developing unbiased rat to human interspecies data extrapolation schemes.

8.
Int J Numer Method Biomed Eng ; : e3565, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34913265

RESUMO

As a primary determinant of nasal physiological functions, the nasal morphology and its effects on the airflow dynamics have been extensively studied in literature. However, gross flow features reported in literature are mostly obtained from subjects at similar ages, while studies focusing on nasal subjects with distinct age differences are significantly less. To advance current understandings of nasal airflow dynamics in the context of age diversity, this study employed three anatomically accurate nasal cavity models with distinct age features (5-, 24- and 77-year-old models) and numerically compared the physiological nasal airflow fields within these nasal cavity models. To demonstrate the validity of the present numerical models, in vivo rhinomanometry measurement was conducted on the 24-year-old female nasal model, and key anatomical features and pressure-flow curves of all three models were compared with models with similar age features in literature work. Apart from results comparison based on conventional velocity flow fields and wall shear stress distributions, a method for quantifying flow partitions in confined airway spaces was developed to reveal the proportions of fractional flow that enters the olfactory region. Our results revealed dramatic intersubject discrepancies between considered nasal cavity models, especially for the fractional flow that enters the olfactory region. Specifically, the 5-year-old girl nasal model received the highest proportion of fractional flow, which accounts for 13.3% ~ 15% of overall inhalation flow rates under different activity levels. For the 24-year-old female model, on the contrary, the olfactory fractional flow was dramatically reduced (with a local to overall percentage around 4.3%-7.7%). Finally, for the elderly subject-77-year-old male model, minimum level of olfactory flux was observed with a local to overall percentage ranging between 3.1% and 4.9% for considered wide range of inhalation flow rates. Therefore, the local flow intersubject variation can reach nearly fourfold. The vast local flow difference is mainly due to the inherent anatomical features (e.g., immature nasal turbinate structure in the child model, the partial narrowing superior nasal valve in the elder model). The results may further lead to discrepant health effects associated with inhalation exposure to airborne particles.

9.
J Appl Toxicol ; 2021 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-34927272

RESUMO

Heavy metals exposure has been associated with liver dysfunction in recent reports, while the hepatoxicity of lead (Pb) and cadmium (Cd) has been well established. However, the combined effects of multi-metal in real-world scenario on liver dysfunction are still unclear. This cross-sectional study examined associations between 10 biomarkers of early liver injury and multiple heavy metals levels. The levels of heavy metals/metalloid (magnesium [Mg], calcium [Ca], iron [Fe], zinc [Zn], arsenic [As], Cd, copper [Cu], and Pb) were measured in blood and urinary sample collected from 725 participants in a Cd-polluted area and an unpolluted area in southwest China. The early liver dysfunction biomarkers included the liver enzymes (ALT, ALP, AST, and GGT), proteins (TP, ALB, and GLO), and bilirubin (TBIL, DBIL, and IBIL). Confounder-adjusted beta coefficients were determined using multiple linear regression model analysis for the group-classified and gender-classified samples. Our results showed that blood Fe, Cd, and Cu levels were found to be positively related to elevated ALT levels and blood Cu was positively associated with AST levels in the Cd-polluted area, while the highest blood Zn quartile in the polluted area and blood Mg quartile in the unpolluted area were associated with lower ALT levels. Our finding implies that industrial pollution results in heavy metals of Cd and Pb exposure and effects of Fe, Cd, Cu, and Pb in the Cd-polluted area may be the main contributors to increase the risk of liver dysfunction while Zn in the Cd-polluted area and Mg in the unpolluted area may be the protective factors.

10.
Autism Res ; 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34967132

RESUMO

The heterogeneous nature of children with symptoms of autism spectrum disorder (ASD) makes it difficult to identify risk factors and effective treatment options. We sought to identify behavioral and developmental features that best define the heterogeneity and homogeneity in 2-5-year-old children classified with ASD and subthreshold ASD characteristics. Children were enrolled in a multisite case-control study of ASD. Detailed behavioral and developmental data were gathered by maternal telephone interview, parent-administered questionnaires, child cognitive evaluation, and ASD diagnostic measures. Participants with a positive ASD screen score or prior ASD diagnosis were referred for comprehensive evaluation. Children in the ASD group met study criteria based on this evaluation; children who did not meet study criteria were categorized as having subthreshold ASD characteristics. There were 1480 children classified as ASD (81.6% boys) and 594 children classified as having subthreshold ASD characteristics (70.2% boys) in the sample. Factors associated with dysregulation (e.g., aggression, anxiety/depression, sleep problems) followed by developmental abilities (e.g., expressive and receptive language skills) most contributed to heterogeneity in both groups of children. Atypical sensory response contributed to homogeneity in children classified as ASD but not those with subthreshold characteristics. These findings suggest that dysregulation and developmental abilities are clinical features that can impact functioning in children with ASD and other DD, and that documenting these features in pediatric records may help meet the needs of the individual child. Sensory dysfunction could be considered a core feature of ASD and thus used to inform more targeted screening, evaluation, treatment, and research efforts. LAY SUMMARY: The diverse nature of autism spectrum disorder (ASD) makes it difficult to find risk factors and treatment options. We identified the most dissimilar and most similar symptom(s) in children classified as ASD and as having subthreshold ASD characteristics. Factors associated with dysregulation and developmental abilities contributed to diversity in both groups of children. Sensory dysfunction was the most common symptom in children with ASD but not those with subthreshold characteristics. Findings can inform clinical practice and research.

11.
J Mater Sci Mater Med ; 33(1): 4, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34940936

RESUMO

The purpose was to observe whether valproic acid (VPA) has a positive effect on bone-defect repair via activating the Notch signaling pathway in an OVX rat model. The MC3T3-E1 cells were cocultured with VPA and induced to osteogenesis, and the osteogenic activity was observed by alkaline phosphatase (ALP) staining, Alizarin Red (RES) staining and Western blotting (WB). Then the hydrogel-containing VPA was implanted into the femoral epiphysis bone-defect model of ovariectomized (OVX) rats for 12 weeks. Micro-CT, biomechanical testing, histology, immunofluorescence, RT-qPCR, and WB analysis were used to observe the therapeutic effect and explore the possible mechanism. ALP and ARS staining and WB results show that the cell mineralization, osteogenic activity, and protein expression of ALP, OPN, RUNX-2, OC, Notch 1, HES1, HEY1, and JAG1 of VPA group is significantly higher than the control group. Micro-CT, biomechanical testing, histology, immunofluorescence, and RT-qPCR evaluation show that group VPA presented the stronger effect on bone strength, bone regeneration, bone mineralization, higher expression of VEGFA, BMP-2, ALP, OPN, RUNX-2, OC, Notch 1, HES1, HEY1, and JAG1 of VPA when compared with OVX group. Our current study demonstrated that local treatment with VPA could stimulate repair of femoral condyle defects, and these effects may be achieved by activating Notch signaling pathway and acceleration of blood vessel and bone formation.

12.
Comput Biol Med ; 141: 105150, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34942396

RESUMO

Nonhuman primates are occasionally used as laboratory models for sophisticated medical research as they bear the closest resemblance to humans in morphometry and physiological functions. A range of nonhuman primate species have been employed in the inhalation toxicity, nasal drug delivery and respiratory viral infection studies, and they provided valuable insight to disease pathogenesis while other laboratory animals such as rodents cannot recapitulate due to the lesser degree of similarity in metabolism, anatomy and cellular response to that of humans. It is anticipated that nonhuman primate models of respiratory diseases will continue to be instrumental for translating biomedical research for improvement of human health, and the confidence in laboratory data extrapolation between species will play a pivotal role. From the morphometry and flow dynamics point of view, this study performed a detailed comparative analysis between human and a cynomolgus monkey nasal airway, with intention to provide high-fidelity qualitative and quantitative linkage between the two species for more effective laboratory data extrapolation. The study revealed that cynomolgus monkey could be a good human surrogate in nasal inhalation studies; however, care should be given for interspecies data extrapolation as subtle differences in anatomy and airflow dynamics were present between the two species.

13.
BMC Psychiatry ; 21(1): 544, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732149

RESUMO

BACKGROUND: Schizophrenia (SZ) and obsessive-compulsive disorder (OCD) share many demographic characteristics and severity of clinical symptoms, genetic risk factors, pathophysiological underpinnings, and brain structure and function. However, the differences in the spontaneous brain activity patterns between the two diseases remain unclear. Here this study aimed to compare the features of intrinsic brain activity in treatment-naive participants with SZ and OCD and to explore the relationship between spontaneous brain activity and the severity of symptoms. METHODS: In this study, 22 treatment-naive participants with SZ, 27 treatment-naive participants with OCD, and sixty healthy controls (HC) underwent a resting-state functional magnetic resonance imaging (fMRI) scan. The amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo) and degree of centrality (DC) were performed to examine the intrinsic brain activity of participants. Additionally, the relationships among spontaneous brain activity, the severity of symptoms, and the duration of illness were explored in SZ and OCD groups. RESULTS: Compared with SZ group and HC group, participants with OCD had significantly higher ALFF in the right angular gyrus and the left middle frontal gyrus/precentral gyrus and significantly lower ALFF in the left superior temporal gyrus/insula/rolandic operculum and the left postcentral gyrus, while there was no significant difference in ALFF between SZ group and HC group. Compared with HC group, lower ALFF in the right supramarginal gyrus/inferior parietal lobule and lower DC in the right lingual gyrus/calcarine fissure and surrounding cortex of the two patient groups, higher ReHo in OCD group and lower ReHo in SZ group in the right angular gyrus/middle occipital gyrus brain region were documented in the present study. DC in SZ group was significantly higher than that in HC group in the right inferior parietal lobule/angular gyrus, while there were no significant DC differences between OCD group and HC group. In addition, ALFF in the left postcentral gyrus were positively correlated with positive subscale score (r = 0.588, P = 0.013) and general psychopathology subscale score (r = 0.488, P = 0.047) respectively on the Positive and Negative Syndrome Scale (PANSS) in SZ group. ALFF in the left superior temporal gyrus/insula/rolandic operculum of participants with OCD were positively correlated with compulsion subscale score (r = 0.463, P = 0.030) on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). The longer the illness duration in SZ group, the smaller the ALFF of the left superior temporal gyrus/insula/rolandic operculum (Rho = 0.-492, P = 0.020). The longer the illness duration in OCD group, the higher the ALFF of the right supramarginal gyrus/inferior parietal lobule (Rho = 0.392, P = 0.043) and the left postcentral gyrus (Rho = 0.385, P = 0.048), and the lower the DC of the right inferior parietal lobule/angular gyrus (Rho = - 0.518, P = 0.006). CONCLUSION: SZ and OCD show some similarities in spontaneous brain activity in parietal and occipital lobes, but exhibit different patterns of spontaneous brain activity in frontal, temporal, parietal, occipital, and insula brain regions, which might imply different underlying neurobiological mechanisms in the two diseases. Compared with OCD, SZ implicates more significant abnormalities in the functional connections among brain regions.

15.
J Agric Food Chem ; 69(48): 14467-14477, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34843231

RESUMO

Crop diseases caused by fungi threaten food security and exacerbate the food crisis. Inspired by the application of fungicide candidates from natural products in agrochemical discovery, a series of luotonin A derivatives were designed, synthesized, and evaluated for their antifungal activities against five plant fungi. Most of these compounds exhibited significant fungicidal activity against Botrytis cinerea in vitro with EC50 values less than 1 µg/mL. Among them, compounds w7, w8, w12, and w15 showed superior antifungal activity against B. cinerea with EC50 values of 0.036, 0.050, 0.042, and 0.048 µg/mL, respectively, which were more potent than boscalid (EC50 = 1.790 µg/mL). Preliminary mechanism studies revealed that compound w7 might pursue its antifungal activity by disrupting the fungal cell membrane and cell wall. Moreover, in vivo bioassay also indicated that compound w7 could be effective for the control of B. cinerea. The above results evidenced the potential of luotonin A derivatives as novel and promising candidate fungicides.

16.
ACS Omega ; 6(44): 29596-29608, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34778631

RESUMO

Development of multi-ligand metal-organic frameworks (MOFs) and derived heteroatom-doped composites as efficient non-noble metal-based catalysts is highly desirable. However, rational design of these materials with controllable composition and structure remains a challenge. In this study, novel hierarchical N-doped CuO/Cu composites were synthesized by assembling dual-ligand MOFs via a solvent-induced coordination modulation/low-temperature pyrolysis method. Different from a homogeneous system, our heterogeneous nucleation strategy provided more flexible and cost-effective MOF production and offered efficient direction/shape-controlled synthesis, resulting in a faster reaction and more complete conversion. After pyrolysis, they further transformed to a unique metal/carbon matrix with regular morphology and, as a hot template, guided the orderly generation of metal oxides, eliminating sintering and agglomeration of metal oxides and initiating a synergistic effect between the N-doped metal oxide/metal and carbon matrix. The prepared N-doped CuO/Cu catalysts held unique water resistance and superior catalytic activity (100% CO conversion at 140 °C).

17.
J Agric Food Chem ; 69(41): 12156-12170, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34623798

RESUMO

Enlightened from our previous work of structural simplification of quinine and innovative application of natural products against phytopathogenic fungi, lead structure 2,8-bis(trifluoromethyl)-4-quinolinol (3) was selected to be a candidate and its diversified design, synthesis, and antifungal evaluation were carried out. All of the synthesized compounds Aa1-Db1 were evaluated for their antifungal activity against four agriculturally important fungi, Botrytis cinerea, Fusarium graminearum, Rhizoctonia solani, and Sclerotinia sclerotiorum. Results showed that compounds Ac3, Ac4, Ac7, Ac9, Ac12, Bb1, Bb10, Bb11, Bb13, Cb1. and Cb3 exhibited a good antifungal effect, especially Ac12 had the most potent activity with EC50 values of 0.52 and 0.50 µg/mL against S. sclerotiorum and B. cinerea, respectively, which were more potent than those of the lead compound 3 (1.72 and 1.89 µg/mL) and commercial fungicides azoxystrobin (both >30 µg/mL) and 8-hydroxyquinoline (2.12 and 5.28 µg/mL). Moreover, compound Ac12 displayed excellent in vivo antifungal activity, which was comparable in activity to the commercial fungicide boscalid. The preliminary mechanism revealed that compound Ac12 might cause an abnormal morphology of cell membranes, an increase in membrane permeability, and release of cellular contents. These results indicated that compound Ac12 displayed superior in vitro and in vivo fungicidal activities and could be a potential fungicidal candidate against plant fungal diseases.


Assuntos
Fungicidas Industriais , Fusarium , Hidroxiquinolinas , Quinolinas , Antifúngicos/farmacologia , Ascomicetos , Botrytis , Fungos , Fungicidas Industriais/farmacologia , Estrutura Molecular , Quinina , Rhizoctonia , Relação Estrutura-Atividade
18.
Chem Biodivers ; : e2100633, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34643056

RESUMO

The increasing resistance of plant diseases caused by phytopathogenic fungi highlights the need for highly effective and environmentally benign agents. The antifungal activities of Cnidium monnieri fruit extracts and five isolated compounds as well as structurally related coumarins against five plant pathogenic fungi were evaluated. The acetone extract, which contained the highest amount of five coumarins, showed strongest antifungal activity. Among the coumarin compounds, we found that 4-methoxycoumarin exhibited stronger and broader antifungal activity against five phytopathogenic fungi, and was more potent than osthol. Especially, it could significantly inhibit the growth of Rhizoctonia solani mycelium with an EC50 value of 21 µg mL-1 . Further studies showed that 4-methoxycoumarin affected the structure and function of peroxisomes, inhibited the ß-oxidation of fatty acids, decreased the production of ATP and acetyl coenzyme A, and then accumulated ROS by damaging MMP and the mitochondrial function to cause the cell death of R. solani mycelia. 4-Methoxycoumarin presented antifungal efficacy in a concentration- dependent manner in vivo and could be used to prevent the potato black scurf. This study laid the foundation for the future development of 4-methoxycournamin as an alternative and friendly biofungicide.

19.
Molecules ; 26(20)2021 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-34684864

RESUMO

Vibrio alginolyticus is a halophilic organism usually found in marine environments. It has attracted attention as an opportunistic pathogen of aquatic animals and humans, but there are very few reports on polyhydroxyalkanoate (PHA) production using V. alginolyticus as the host. In this study, two V. alginolyticus strains, LHF01 and LHF02, isolated from water samples collected from salt fields were found to produce poly(3-hydroxybutyrate) (PHB) from a variety of sugars and organic acids. Glycerol was the best carbon source and yielded the highest PHB titer in both strains. Further optimization of the NaCl concentration and culture temperature improved the PHB titer from 1.87 to 5.08 g/L in V. alginolyticus LHF01. In addition, the use of propionate as a secondary carbon source resulted in the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). V. alginolyticus LHF01 may be a promising host for PHA production using cheap waste glycerol from biodiesel refining.


Assuntos
Poli-Hidroxialcanoatos/biossíntese , Vibrio alginolyticus/metabolismo , Carbono/metabolismo , China , Fermentação , Águas Salinas , Vibrio alginolyticus/isolamento & purificação , Vibrio alginolyticus/ultraestrutura
20.
Cell ; 184(22): 5622-5634.e25, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34610277

RESUMO

Disinhibitory neurons throughout the mammalian cortex are powerful enhancers of circuit excitability and plasticity. The differential expression of neuropeptide receptors in disinhibitory, inhibitory, and excitatory neurons suggests that each circuit motif may be controlled by distinct neuropeptidergic systems. Here, we reveal that a bombesin-like neuropeptide, gastrin-releasing peptide (GRP), recruits disinhibitory cortical microcircuits through selective targeting and activation of vasoactive intestinal peptide (VIP)-expressing cells. Using a genetically encoded GRP sensor, optogenetic anterograde stimulation, and trans-synaptic tracing, we reveal that GRP regulates VIP cells most likely via extrasynaptic diffusion from several local and long-range sources. In vivo photometry and CRISPR-Cas9-mediated knockout of the GRP receptor (GRPR) in auditory cortex indicate that VIP cells are strongly recruited by novel sounds and aversive shocks, and GRP-GRPR signaling enhances auditory fear memories. Our data establish peptidergic recruitment of selective disinhibitory cortical microcircuits as a mechanism to regulate fear memories.

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