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The integration of molecular machines and motors into materials represents a promising avenue for creating dynamic and functional molecular systems, with potential applications in soft robotics or reconfigurable biomaterials. However, the development of truly scalable and controllable approaches for incorporating molecular motors into polymeric matrices has remained a challenge. Here, it is shown that light-driven molecular motors with sensitive photo-isomerizable double bonds can be converted into initiators for Cu-mediated controlled/living radical polymerization enabling the synthesis of star-shaped motor-polymer conjugates. This approach enables scalability, precise control over the molecular structure, block copolymer structures, and high-end group fidelity. Moreover, it is demonstrated that these materials can be crosslinked to form gels with quasi-ideal network topology, exhibiting light-triggered contraction. The influence of arm length and polymer structure is investigated, and the first molecular dynamics simulation framework to gain deeper insights into the contraction processes is developed. Leveraging this scalable methodology, the creation of bilayer soft robotic devices and cargo-lifting artificial muscles is showcased, highlighting the versatility and potential applications of this advanced polymer chemistry approach. It is anticipated that the integrated experimental and simulation framework will accelerate scalable approaches for active polymer materials based on molecular machines, opening up new horizons in materials science and bioscience.
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Depression is among the most frequent psychiatric comorbid conditions in Alzheimer disease (AD). However, pharmacotherapy for depressive disorders in AD is still a big challenge, and the data on the efffcacy of current antidepressants used clinically for depressive symptoms in patients with AD remain inconclusive. Here we investigated the mechanism of the interactions between depression and AD, which we believe would aid in the development of pharmacological therapeutics for the comorbidity of depression and AD. Female APP/PS1/Tau triple transgenic (3×Tg-AD) mice at 24 months of age and age- and sex-matched wild-type (WT) mice were used. The shuttle-box passive avoidance test (PAT) were implemented to assess the abilities of learning and memory, and the open field test (OFT) and the tail suspension test (TST) were used to assess depression-like behavior. High-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was used to detect the level of neurotransmitters related to depression in the hippocampus of mice. The data was identified by orthogonal projections to latent structures discriminant analysis (OPLS-DA). Most neurotransmitters exert their effects by binding to the corresponding receptor, so the expression of relative receptors in the hippocampus of mice was detected using Western blot. Compared to WT mice, 3×Tg-AD mice displayed significant cognitive impairment in the PAT and depression-like behavior in the OFT and TST. They also showed significant decreases in the levels of L-tyrosine, norepinephrine, vanillylmandelic acid, 5-hydroxytryptamine, and acetylcholine, in contrast to significant increases in 5-hydroxyindoleacetic acid, L-histidine, L-glutamine, and L-arginine in the hippocampus. Moreover, the expression of the alpha 1a adrenergic receptor (ADRA1A), serotonin 1 A receptor (5HT1A), and γ-aminobutyric acid A receptor subunit alpha-2 (GABRA2) was significantly downregulated in the hippocampus of 3×Tg-AD mice, while histamine H3 receptor (H3R) expression was significantly upregulated. In addition, the ratio of phosphorylated cAMP-response element-binding protein (pCREB) and CREB was significantly decreased in the hippocampus of 3×Tg-AD mice than WT mice. We demonstrated in the present study that aged female 3×Tg-AD mice showed depression-like behavior accompanied with cognitive dysfunction. The complex and diverse mechanism appears not only relevant to the imbalance of multiple neurotransmitter pathways, including the transmitters and receptors of the monoaminergic, GABAergic, histaminergic, and cholinergic systems, but also related to the changes in L-arginine and CREB signaling molecules.
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Doença de Alzheimer , Disfunção Cognitiva , Camundongos , Feminino , Animais , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Doença de Alzheimer/tratamento farmacológico , Camundongos Transgênicos , Espectrometria de Massas em Tandem , Depressão/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Hipocampo/metabolismo , Neurotransmissores/metabolismo , Modelos Animais de Doenças , Peptídeos beta-Amiloides/farmacologia , Proteínas tau/metabolismoRESUMO
Objective: This study aimed to examine the trends in stroke mortality among young and middle-aged adults in China. Methods: Data were obtained from the China national vital registration system. Significant changes in mortality were assessed by Joinpoint regression. Age-period-cohort analysis was used to explain the reasons for the changes. Future mortality and counts were predicted by the Bayesian age-period-cohort model. Results: Between 2002 and 2019, a total of 6,253,951 stroke mortality in young and middle-aged adults were recorded. The age-adjusted mortality rates (AAMRs) of women showed a downward trend. The annual percent changes (APC) were -3.5% (-5.2%, -1.7%) for urban women and -2.8% (-3.7%, -1.9%) for rural women. By contrast, the AAMRs per 100,000 for rural men aged 25-44 years continued to rise from 9.40 to 15.46. The AAMRS for urban men aged 25-44 years and urban and rural men aged 45-64 years did not change significantly. Between 2020 and 2030, the projected stroke deaths are 1,423,584 in men and 401,712 in women. Conclusion: Significant sex and age disparities in the trends of stroke mortality among young and middle-aged adults were identified in China. Targeted health policy measures are needed to address the burden of stroke in the young generation, especially for rural men, with a focus on the prevention and management of high risk factors.
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Acidente Vascular Cerebral , Pessoa de Meia-Idade , Masculino , Adulto , Humanos , Feminino , Teorema de Bayes , População Urbana , Acidente Vascular Cerebral/epidemiologia , Estudos de Coortes , China/epidemiologia , MortalidadeRESUMO
Objective: To investigate the influence of osteoarthritis (OA) at different sites and of different degrees on the prevalence of osteoporosis (OP) and lumbar bone mineral density (L-BMD) in men, and thereby to analyze the relationship between OA and OP. Methods: We collected information on the age, height, body mass, the course of pain, smoking status, exercise status, and history of hypertension and diabetes of 1206 male patients who received treatment for bone and joint pain at the Department of Osteoporosis and Rheumatology, West China Fourth Hospital, Sichuan University between January 2017 and December 2020. The patients' L-BMD was determined with dual-energy X-ray absorptiometry. The sites and the degrees of OA were evaluated by digital radiography and CT or MRI. χ 2 test was performed to compare the OP prevalence of different groups. Analysis of covariance was carried out to compare the L-BMD of different groups. Binary logistic regression was conducted to analyze the risk factors of OP. Results: OP prevalence of the OA group was significantly lower than that of the non-OA group ( P<0.05). OP prevalence of the lumbar vertebra OA group was significantly lower than that of the non-OA group ( P<0.05). In addition, OP prevalence of the mild OA group and moderate OA group was significantly lower than of the non-OA group ( P<0.05). The L-BMD of the OA group was significantly higher than that of the non-OA group ( P<0.05). In addition, there were significant differences in L-BMD between groups with OA at different sites ( P<0.05). Furthermore, the L-BMD of the lumbar vertebra OA group and the multi-site OA group was significantly higher than that of the non-OA group ( P<0.05). There were significant differences in L-BMD between groups with different degrees of OA ( P<0.05). Furthermore, the L-BMD of the mild OA group and moderate OA group was significantly higher than that of the non-OA group ( P<0.05). OA and exercise were found to be protective factors for OP (odds ratio [ OR]=0.715 and 0.625, 95% confidence interval [ CI]: 0.550-0.928 and 0.481-0.814, P<0.05). Age and BMI were found to be risk factors for OP in men ( OR=1.018 and 1.081, 95% CI: 1.008-1.028 and 1.042-1.122, P<0.05). Conclusion: Lumbar vertebra OA and mild and moderate OA decrease OP prevalence in men, while lumbar vertebra OA, multi-site OA, and mild and moderate OA increase L-BMD in men. OA and exercise decrease the occurrence of OP in men, while age and BMI increase the risk of OP in men.
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Osteoartrite , Osteoporose , Humanos , Masculino , Osteoporose/epidemiologia , Densidade Óssea , Osteoartrite/epidemiologia , Absorciometria de Fóton , Fatores de RiscoRESUMO
The unidirectional rotation of chemically crosslinked light-driven molecular motors is shown to progressively shift the swelling equilibrium of hydrogels. The concentration of molecular motors and the initial strand density of the polymer network are key parameters to modulate the macroscopic contraction of the material, and both parameters can be tuned using polymer chains of different molecular weights. These findings led to the design of optimized hydrogels revealing a half-time contraction of approximately 5â min. Furthermore, under inhomogeneous stimulation, the local contraction event was exploited to design useful bending actuators with an energy output 400 times higher than for previously reported self-assembled systems involving rotary motors. In the present configuration, we measure that a single molecular motor can lift up loads of 200 times its own molecular weight.
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One new alkaloid, 6, 7-dimethoxyisoquinoline-N-oxide (1), one new benzofuran derivative, 3,7-dimethyl-6-acetyl-8-benzofuranol (2) and one new lignan, salsolains A (3), along with seven known compounds (4-10), were isolated from the whole plant of Salsola collina Pall. Their structures were elucidated by extensive analysis of spectroscopic data (IR, UV, HR-ESI-MS, 1 D and 2 D NMR), and their absolute configurations were determined by the X-ray crystallography and ECD calculation. The activities of compounds 1-10 against inflammatory cytokines IL-6 and TNF-α levels on LPS-induced RAW 264.7 macrophages were assessed, especially, compound 5 (50 µM) exhibited the most significant anti-inflammatory activity with the secretion levels of IL-6 and TNF-α at 3.87% and 4.03%, respectively.
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Alcaloides , Salsola , Animais , Camundongos , Salsola/química , Fator de Necrose Tumoral alfa , Interleucina-6 , Macrófagos , Células RAW 264.7 , Estrutura MolecularRESUMO
The detection method of characteristic spectrum for reference samples was established by preparing 15 batches of the reference samples of Huagan Decoction, and the peak attribution and the similarity range in the characteristic spectrum were clarified. The ranges of paste-forming rate, content, and transfer rate of the index components including geniposide, paeonol, and paeoniflorin were analyzed. The key quality attribute of the reference samples of Huagan Decoction was defined. The results showed that the 15 batches of the reference samples of Huagan Decoction had good similarities in the characteristic spectrum, which were all higher than 0.9. According to the information of characteristic peak, there were 18 characteristic peaks in the whole prescription, including seven common characteristic peaks from green tangerine peel and dried tangerine peel, four characteristic peaks from tree peony root bark(three of them were common characteristic peaks from tree peony root bark and red peony root), five characteristic peaks from cape jasmine fruit, one characteristic peak from paniculate bolbostemma, and one characteristic peak from oriental waterplantain rhizome.The paste-forming rate of the 15 batches of reference samples was 14.73%-18.83%. The content of geniposide was 1.68%-2.87%, with the average transfer rate of 70.05%±11.13%. The content of paeonol was 0.10%-0.16%, with the average transfer rate of 9.38%±1.78%. The content of paeoniflorin was 1.94%-2.74%, with the average transfer rate of 36.69%±4.63%. This study analyzed the quality value transfer of the reference samples of Huagan Decoction by the evaluation mode of combining the characteristic spectrum, the paste-forming rate, and the content of index components. The findings of this study initially established a stable and feasible standard decoction evaluation method and provided references for the quality control and the subsequent development of relevant preparations of Huagan Decoction.
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Medicamentos de Ervas Chinesas , Paeonia , Cromatografia Líquida de Alta Pressão , Prescrições , Controle de QualidadeRESUMO
China faces the greatest challenge from stroke in the world. According to results from the Global Burden of Disease Study 2019, there were 3.94 million new stroke cases, 28.76 million prevalent cases and 2.19 million deaths due to stroke in China in 2019. Furthermore, stroke is also the leading cause of disability-adjusted life-year (DALY) in China, the number of DALYs reached 45.9 million in 2019. Several recent large-scale epidemiological surveys have updated the data on pre-existing conditions contributed to stroke. The age-adjusted prevalence of overweight among Chinese adults aged 18-69 years was 34.4%, and the prevalence of obesity was 16.8% in 2018. 50.9% of Chinese adults ≥18 years of age without history of hypertension had prehypertension in 2018. The weighted prevalence of hypertension in adults was 27.5% in 2018. The weighted prevalence of total diabetes and pre-diabetes diagnosed by the American Diabetes Association criteria were 12.8% and 35.2%, respectively, among Chinese adults ≥18 years of age in 2017. The weighted atrial fibrillation prevalence was 1.8% among Chinese adults ≥45 years of age and equates to being present in an estimated 7.9 million people in China. Data from 1672 tertiary public hospitals in the Hospital Quality Monitoring System (HQMS) showed that 3 411 168 stroke cases were admitted during 2019. Of those, 2 818 875 (82.6%) were ischaemic strokes (ISs), 485 474 (14.2%) were intracerebral haemorrhages (ICHs), 106 819 (3.1%) were subarachnoid haemorrhages (SAHs). The average age was 66 years old, and 59.6% were male. A total of 1379 (<0.1%), 2604 (0.5%), 1250 (1.2%) paediatric strokes (age <18 years) were identified among IS, ICH and SAH, respectively. Over one-third (1 231 519 (36.1%)) of the stroke cases were covered by urban resident basic medical insurance, followed by urban employee basic medical insurance (891 103 (26.1%)) and new rural cooperative medical schema (543 108 (15.9%)). The leading risk factor was hypertension (57.3% for IS, 69.9% for ICH and 44.1% for SAH), and the leading comorbidity was pneumonia or pulmonary infection (10.4% for IS, 34.6% for ICH and 29.7% for SAH). In-hospital death/discharge against medical advice rate was 8.5%, ranging from 6.0% for IS to 20.6% for SAH. The median and IQR of length of stay was 9.0 (6.0-13.0) days, ranging from 10.0 (7.0-13.0) in IS to 14.0 (8.0-22.0) in ICH. Similar data from 2847 secondary public hospitals or private hospitals in the HQMS were also reported. Data from HQMS showed that higher proportions of interprovincial admission to other provinces were seen in Inner Mongolia, Anhui, Tibet and Beijing. Higher proportions of interprovincial admission from other provinces were seen in Beijng, Tianjin, Shanghai and Ningxia. Data from 323 601 strokes from 1337 hospitals in the Chinese Stroke Center Alliance during 2019 demonstrated that the composite scores of guideline-recommended key performance indicators for patients with IS, ICH and SAH were 0.78±0.20, 0.69±0.27 and 0.60±0.31, respectively.
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Hipertensão , Doenças não Transmissíveis , Acidente Vascular Cerebral , Adulto , Criança , Humanos , Masculino , Idoso , Adolescente , Pessoa de Meia-Idade , Feminino , Estados Unidos , China/epidemiologia , Mortalidade Hospitalar , Doenças não Transmissíveis/epidemiologia , Doenças não Transmissíveis/terapia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Fatores de Risco , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/terapia , Centers for Disease Control and Prevention, U.S.RESUMO
Three new sesquiterpene lactones, named scabertopinolides H - J (1 - 3), along with four known ones, desacylisodeoxyelephantopin 2-methylbutyrate (4), iso-17,19-dihydrodeoxyelephantopin (5), scabertopinolide D (6) and (2R,6R,7R,8S)-8-tigloyloxy-1(10),4(5),11(13)-germacratrien-2,15,6,12-diolide (7) were isolated from the whole plants of Elephantopus scaber. Their structures were elucidated by extensive analysis of spectroscopic data (including IR, UV, HRESIMS, 1 D and 2 D NMR) and single-crystal X-ray. These isolated compounds showed effective anti-inflammatory effects on LPS-stimulated RAW 264.7 cells with IC50 values of 6.27 ± 0.18 to 18.31 ± 1.38 µM.
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Asteraceae , Sesquiterpenos , Animais , Asteraceae/química , Lactonas/química , Lactonas/farmacologia , Camundongos , Estrutura Molecular , Compostos Fitoquímicos , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/farmacologiaRESUMO
The small-eared shrew genus Cryptotis is the third largest in the family Soricidae and occurs in North, Central, and northern South America. In Mexico and Central and South America, most species inhabit geographically isolated moist, montane habitats at middle and high elevations in a typical sky-island pattern. The 49 recognized species have been partitioned into as many as six species groups based on morphological and molecular phylogenetic studies. The relationships among these species groups are poorly resolved, and their evolutionary histories, including migration patterns and locomotor adaptations, remain unclear. Herein, we provide a new phylogeny incorporating complete mitochondrial genomes (mitogenomes) and supermatrix approach. We compared different evolutionary scenarios using approximately unbiased (AU), Kishino-Hasegawa (KH), and Shimodaira-Hasegawa (SH) statistical tests. The phylogenetic hypothesis based on mitogenomes revealed novel relationships supporting a basal position for the Cryptotis parvus-group in the genus, and a close relationship between C. gracilis and one clade of the C. thomasi-group. The former relationship is consistent with the least derived humerus morphology and northern distribution of the species. The latter relationship implies multiple migrations between Central and South America. The lack of fine resolution for the species group relationships may be due partly to the lack of taxon sampling. In contrast, multi-approach analyses suggest that the unresolved relationships may be a result of rapid diversification during the early stages of Cryptotis evolution.
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Especiação Genética , Genômica , Filogenia , Musaranhos/classificação , Musaranhos/genética , AnimaisRESUMO
A hydrophobic light-driven rotary motor is functionalized with two 18-crown-6 macrocycles and incorporated into phospholipid bilayers. In the presence of this molecular construct, fluorescence assays and patch clamp experiments show the formation of selective alkali ion channels through the membrane. Further, they reveal a strongly accelerated ion transport mechanism under light irradiation. This increase of the fractional ion transport activity (up to 400%) is attributed to the out-of-equilibrium actuation dynamics of the light-driven rotary motors, which help to overcome the activation energy necessary to achieve translocation of alkali ions between macrocycles along the artificial channels.
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BACKGROUND: Phospholipid transfer protein (PLTP) belongs to the lipid transfer glycoprotein family. Studies have shown that it is closely related to Alzheimer's disease (AD); however, the exact effect and mechanism remain unknown. OBJECTIVE: To observe the effect of PLTP overexpression on behavioral dysfunction and the related mechanisms in APP/PS1/Tau triple transgenic (3×Tg-AD) mice. METHODS: AAV-PLTP-EGFP was injected into the lateral ventricle to induce PLTP overexpression. The memory of 3×Tg-AD mice and wild type (WT) mice aged 10 months were assessed using Morris water maze (MWM) and shuttle-box passive avoidance test (PAT). Western blotting and ELISA assays were used to quantify the protein contents. Hematoxylin and eosin, Nissl, and immunochemistry staining were utilized in observing the pathological changes in the brain. RESULTS: 3×Tg-AD mice displayed cognitive impairment in WMW and PAT, which was ameliorated by PLTP overexpression. The histopathological hallmarks of AD, senile plaques and neurofibrillary tangles, were observed in 3×Tg-AD mice and were improved by PLTP overexpression. Besides, the increase of amyloid-ß42 (Aß42) and Aß40 were found in the cerebral cortex and hippocampus of 3×Tg-AD mice and reversed by PLTP overexpression through inhibiting APP and PS1. PLTP overexpression also reversed tau phosphorylation at the Ser404, Thr231 and Ser199 of the hippocampus in 3×Tg-AD mice. Furthermore, PLTP overexpression induced the glycogen synthase kinase 3ß (GSK3ß) inactivation via upregulating GSK3ß (pSer9). CONCLUSION: These results suggest that PLTP overexpression has neuroprotective effects. These effects are possibly achieved through the inhibition of the Aß production and tau phosphorylation, which is related to GSK3ß inactivation.
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Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Córtex Cerebral/metabolismo , Cognição/efeitos dos fármacos , Camundongos Transgênicos , Proteínas de Transferência de Fosfolipídeos/metabolismo , Proteínas tau/metabolismo , Animais , Encéfalo/patologia , Córtex Cerebral/patologia , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Teste do Labirinto Aquático de Morris , Fármacos Neuroprotetores/farmacologia , Fosforilação , Placa Amiloide/patologiaRESUMO
Eight new stilbene dimer xylosides (1-8) and one new flavanol (9), along with seven known ones (10-16) were isolated from the roots of Lysidice rhodostegia. Their structures were elucidated by extensive analysis of spectroscopic data (IR, UV, HR-ESI-MS, 1D and 2D NMR), ECD calculations and acid hydrolysis. Compounds 1-16 were evaluated for their antioxidant activities using DPPH radical-scavenging assay. Especially, compounds 9 and 10 exhibited stronger antioxidant effects than the positive control (vitamin E), with IC50 values of 9.57 ± 1.30 and 13.60 ± 1.47 µM, respectively.
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Antioxidantes/farmacologia , Fabaceae/química , Glicosídeos/farmacologia , Polifenóis/farmacologia , Estilbenos/farmacologia , Antioxidantes/isolamento & purificação , China , Glicosídeos/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química , Polifenóis/isolamento & purificação , Estilbenos/isolamento & purificaçãoRESUMO
Phosphodiesterase 7 (PDE7), one of the 11 phosphodiesterase (PDE) families, specifically hydrolyzes cyclic 3', 5'-adenosine monophosphate (cAMP). PDE7 is involved in many important functional processes in physiology and pathology by regulating intracellular cAMP signaling. Studies have demonstrated that PDE7 is widely expressed in the central nervous system (CNS) and potentially related to pathogenesis of many CNS diseases. Here, we summarized the classification and distribution of PDE7 in the brain and its functional roles in the mediation of CNS diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), multiple sclerosis (MS), and schizophrenia. It is expected that the findings collected here will not only lead to a better understanding of the mechanisms by which PDE7 mediates CNS function and diseases, but also aid in the development of novel drugs targeting PDE7 for treatment of CNS diseases.
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Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/metabolismo , Esclerose Múltipla/metabolismo , Doença de Parkinson/metabolismo , Esquizofrenia/metabolismo , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/antagonistas & inibidores , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/genética , Humanos , Terapia de Alvo Molecular , Esclerose Múltipla/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Inibidores de Fosfodiesterase/uso terapêutico , Isoformas de ProteínasRESUMO
Five matrine-type alkaloids (1â5) including two new compounds (1 and 3) and a new natural product (2) were isolated from the roots of Sophora tonkinesis. Their structures were identified by extensive spectroscopic analysis (UV, IR, HRESIMS and NMR). The absolute configurations of 2 and 3 were determined by X-ray diffraction. Compounds 1â5 were evaluated their activity against inflammatory cytokines TNF-α and IL-6 levels on LPS-induced RAW 264.7 macrophages, and compound 1 showed the most significant activity, potent than that of matrine, the representative ingredient from Sophora plants.
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Alcaloides/farmacologia , Anti-Inflamatórios/química , Quinolizinas/farmacologia , Sophora/química , Alcaloides/química , Animais , China , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Raízes de Plantas/química , Células RAW 264.7 , MatrinasRESUMO
The value evaluation of endangered species can provide important supports for policy-making in biodiversity conservation. We evaluated the stakeholders' preference and willingness to pay (WTP) from the perspective of stakeholders by the choice experiment method (CEM) and discussed the ecological compensation mechanism, with Elaeagnus mollis, a national secondary key protected plant as an example. Based on the interest demands analysis of three stakeholders, the management departments, enterprises and farmers, we measured five species attributes of E. mollis, including planting area, product classification, seedling varieties, protection investment, and far-mers' income. Furthermore, the preference of stakeholders and WTP for different attribute variables were analyzed using random parameter model (RPL). The results showed that the preference of respondents for the variable of "increase investment in protection" was the strongest and WTP was the highest (331.00 yuan·a-1·household-1). The stakeholders had stronger preference for the variables of "simultaneous development of high and low-end products" and "development of high-end products", with WTP being 242.71 and 227.57 yuan·a-1·household-1, respectively. For the variables of "farmers' income", "unchanged investment in protection", "seedling varieties" and "planting area", stakeholders showed certain preference and WTP from strong to weak. The prefe-rence for "no investment in protection" and "development of low-end products" was weaker and the WTP was negative. Through direct and indirect approaches of compensation, ecological compensation could be implemented for the objects of ecological compensation (E. mollis and associated habitat). The value of compensating surplus (CS) calculated was 285.62 yuan·a-1·household-1.
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Elaeagnaceae , Espécies em Perigo de Extinção , Animais , Compensação e Reparação , Ecossistema , Fazendeiros , HumanosRESUMO
The silver butter catfish (Schilbe intermedius) is widely distributed across African river systems. To date, information on its mitochondrial genetic diversity, population structure, and historical demography are not well-established. Herein, we combined newly generated mitochondrial cytochrome c oxidase (COI) subunit I gene sequences with previously published COI sequences in the global databases to reconstruct its phylogeography, population genetic structure, and historical demography. Results from the mtDNA phylogeography and species delimitation tests (Cluster algorithm - Species Identifier, Automatic Barcode Gap Discovery and Poison Tree Process model) revealed that S. intermedius comprises at least seven geographically defined matrilines. Although the overall haplotype diversity of S. intermedius was high (h = 0.90), results showed that East (Kenya) and West (Nigeria) African populations had low levels of haplotype diversity (h = ~0.40). In addition, population genetic polymorphism and historical demographics showed that S. intermedius populations in both East and West Africa underwent severe contractions as a result of biogeographic influences. The patterns of genetic diversity and population structure were consistent with adaptive responses to historical biogeographic factors and contemporary environmental variations across African river systems. This is suggestive of the influence of historical biogeographic factors and climatic conditions on population divergence of S. intermedius across African river systems. Given our discovery of previously underappreciated diversity within S. intermedius, we recommend that this species be considered for increased conservation and management.
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Peixes-Gato/genética , Código de Barras de DNA Taxonômico , DNA Mitocondrial/genética , Variação Genética , Filogenia , Animais , Quênia , Nigéria , Filogeografia , RiosRESUMO
The application of resting state functional MRI (RS-fMRI) in Parkinson's disease (PD) was widely performed using standard statistical tests, however, the machine learning (ML) approach has not yet been investigated in PD using RS-fMRI. In current study, we utilized the mean regional amplitude values as the features in patients with PD (nâ¯=â¯72) and in healthy controls (HC, nâ¯=â¯89). The t-test and linear support vector machine were employed to select the features and make prediction, respectively. Three frequency bins (Slow-5: 0.0107-0.0286â¯Hz; Slow-4: 0.0286-0.0821â¯Hz; conventional: 0.01-0.08â¯Hz) were analyzed. Our results showed that the Slow-4 may provide important information than Slow-5 in PD, and it had almost identical classification performance compared with the Combined (Slow-5 and Slow-4) and conventional frequency bands. Similar with previous neuroimaging studies in PD, the discriminative regions were mainly included the disrupted motor system, aberrant visual cortex, dysfunction of paralimbic/limbic and basal ganglia networks. The lateral parietal lobe, such as right inferior parietal lobe (IPL) and supramarginal gyrus (SMG), was detected as the discriminative features exclusively in Slow-4. Our findings, at the first time, indicated that the ML approach is a promising choice for detecting abnormal regions in PD, and a multi-frequency scheme would provide us more specific information.
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Doença de Parkinson , Córtex Visual , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Doença de Parkinson/diagnóstico por imagem , DescansoRESUMO
Sugarcane is an important sugar and energy crop worldwide. It utilises highly efficient C4 photosynthesis and accumulates sucrose in its culms. The sucrose content in sugarcane culms is a quantitative trait controlled by multiple genes. The regulatory mechanism underlying the maximum sucrose level in sugarcane culms remains unclear. We used transcriptome sequences to identify the potential regulatory genes involved in sucrose accumulation in Saccarum officinarum L. cv. Badila. The sucrose accumulating internodes at the elongation and mature growth stage and the immature internodes with low sucrose content at the mature stage were used for RNA sequencing. The obtained differentially expressed genes (DEGs) related to sucrose accumulation were analysed. Results showed that the transcripts encoding invertase (beta-fructofuranosidase, EC: 3.2.1.26) which catalyses sucrose hydrolysis and 6-phosphofructokinase (PFK, EC: 2.7.1.11), a key glycolysis regulatory enzyme, were downregulated in the high sucrose accumulation internodes. The transcripts encoding key enzymes for ABA, gibberellin and ethylene synthesis were also downregulated during sucrose accumulation. Furthermore, regulated protein kinase, transcription factor and sugar transporter genes were also obtained. This research can clarify the molecular regulation network of sucrose accumulation in sugarcane.
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Saccharum/metabolismo , Sacarose/metabolismo , Transcriptoma/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Saccharum/genéticaRESUMO
The construction of synthetic two-dimensional (2D) materials designates a pathway to the versatile chemical functionality by spatial control. However, current 2D materials with intelligence of stimuli-responsibility and adaptiveness have been unfledged. The approach reported here uses a supramolecular strategy to achieve the dynamic non-covalent self-assembly of a rationally designed small molecule monomer, producing large-area, ultra-thin, porous 2D supramolecular assemblies, which are solution-processable in aqueous solution. Importantly, the 2D supramolecular assemblies exhibit distinct adaptive capability to automatically regulate their network density and pore diameters in response to environmental temperature change, which could be developed into an "on-demand" filtration application for nanoparticles. Meanwhile, the 2D supramolecular assemblies can also perform reversible degradation/reformation by photo-irradiation. Our results not only show the simplicity, reliability, and effectiveness of supramolecular strategies in the construction of 2D materials with practical sizes, but also push the dynamic alterability and adaptation features from supramolecular assemblies toward 2D materials.