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1.
Nat Prod Rep ; 39(11): 2132-2174, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36111621

RESUMO

Covering: 2013 to 2021As the characteristic metabolites of Euphorbia plants, Euphorbia diterpenoids have always been a hot topic in related science communities due to their intriguing structures and broad bioactivities. In this review, we intent to provide an in-depth and extensive coverage of Euphorbia diterpenoids reported from 2013 to the end of 2021, including 997 new Euphorbia diterpenoids and 78 known ones with latest progress. Multiple aspects will be summarized, including their occurrences, chemical structures, bioactivities, and syntheses, in which the structure-activity relationship and biosynthesis of this class will be discussed for the first time.


Assuntos
Diterpenos , Euphorbia , Euphorbia/química , Diterpenos/farmacologia , Diterpenos/química , Relação Estrutura-Atividade , Estrutura Molecular
2.
Lab Invest ; 101(10): 1363-1370, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34234270

RESUMO

The wound-healing process is a natural response to burn injury. Resveratrol (RES) may have potential as a therapy for wound healing, but how and whether RES regulates skin repair remains poorly understood. Human epidermal keratinocyte (HaCaT) cells were treated with lipopolysaccharide (LPS), and a mouse skin wound-healing model was established. Cell viability and apoptosis were analyzed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide or flow cytometry. Cell proliferation was assessed by cell viability and colony-formation analyses. Cell migration was tested by wound-healing analysis. The microRNA-212 (miR-212) and caspase-8 (CASP8) levels were determined by quantitative reverse transcription polymerase chain reaction and western blotting. The correlation between miR-212 and CASP8 was analyzed by dual-luciferase reporter analysis. Skin wound healing in mice was assessed by measuring the wound area and gap after hematoxylin-eosin (HE) staining. RES reduced the LPS-induced reduction in viability and apoptosis in HaCaT cells. miR-212 expression was reduced by LPS and increased by exposure to RES. RES promoted cell proliferation and migration after LPS treatment by increasing miR-212 levels. CASP8 was a target of miR-212. CASP8 silencing promoted cell proliferation and migration, which was reversed by miR-212 knockdown in LPS-treated HaCaT cells. RES promoted skin wound healing in mice, which was reduced by miR-212 knockdown. Thus, RES facilitates cell proliferation and migration in LPS-treated HaCaT cells and promotes skin wound-healing in a mouse model by regulating the miR-212/CASP8 axis.


Assuntos
Caspase 8/metabolismo , MicroRNAs/metabolismo , Resveratrol/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
3.
Sci Total Environ ; 928: 172397, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608889

RESUMO

Microplastic biofilms are novel vectors for the transport and spread of pathogenic and drug-resistant bacteria. With the increasing use of bio-based plastics, there is an urgent need to investigate the microbial colonization characteristics of these materials in seawater, particularly in comparison with conventional petroleum-based plastics. Furthermore, the effect of co-occurring contaminants, such as heavy metals, on the formation of microplastic biofilms and bacterial communities remains unclear. In this study, we compared the biofilm bacterial community structure of petroleum-based polyethylene (PE) and bio-based polylactic acid (PLA) in seawater under the influence of zinc ions (Zn2+). Our findings indicate that the biofilm on PLA microplastics in the late stage was impeded by the formation of a mildly acidic microenvironment resulting from the hydrolysis of the ester group on PLA. The PE surface had higher bacterial abundance and diversity, with a more intricate symbiotic pattern. The bacterial structures on the two types of microplastics were different; PE was more conducive to the colonization of anaerobic bacteria, whereas PLA was more favorable for the colonization of aerobic and acid-tolerant species. Furthermore, Zn increased the proportion of the dominant genera that could utilize microplastics as a carbon source, such as Alcanivorax and Nitratireductor. PLA had a greater propensity to harbor and disseminate pathogenic and drug-resistant bacteria, and Zn promoted the enrichment and spread of harmful bacteria such as, Pseudomonas and Clostridioides. Therefore, further research is essential to fully understand the potential environmental effects of bio-based microplastics and the role of heavy metals in the dynamics of bacterial colonization.


Assuntos
Biofilmes , Microplásticos , Água do Mar , Poluentes Químicos da Água , Zinco , Biofilmes/efeitos dos fármacos , Água do Mar/química , Água do Mar/microbiologia , Microplásticos/toxicidade , Poluentes Químicos da Água/análise , Petróleo , Bactérias/efeitos dos fármacos , Poliésteres , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos
4.
Mater Today Bio ; 20: 100634, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37139464

RESUMO

According to the World Health Organization, corneal blindness constitutes 5.1% of global blindness population. Surgical outcomes have been improved significantly in the treatment of corneal blindness. However, corneal transplantation is limited by global shortage of donor tissue, prompting researchers to explore alternative therapies such as novel ocular pharmaceutics to delay corneal disease progression. Animal models are commonly adopted for investigating pharmacokinetics of ocular drugs. However, this approach is limited by physiological differences in the eye between animals and human, ethical issues and poor bench-to-bedside translatability. Cornea-on-a-chip (CoC) microfluidic platforms have gained great attention as one of the advanced in vitro strategies for constructing physiologically representative corneal models. With significant improvements in tissue engineering technology, CoC integrates corneal cells with microfluidics to recapitulate human corneal microenvironment for the study of corneal pathophysiological changes and evaluation of ocular drugs. Such model, in complement to animal studies, can potentially accelerate translational research, in particular the pre-clinical screening of ophthalmic medication, driving clinical treatment advancement for corneal diseases. This review provides an overview of engineered CoC platforms with respect to their merits, applications, and technical challenges. Emerging directions in CoC technology are also proposed for further investigations, to accentuate preclinical obstacles in corneal research.

5.
Huan Jing Ke Xue ; 44(12): 6433-6440, 2023 Dec 08.
Artigo em Zh | MEDLINE | ID: mdl-38098372

RESUMO

Meteorological conditions play a key role in the occurrence and evolution of atmospheric complex pollution. Considering the different pollution formation mechanisms of PM2.5 and O3, statistical calculation and in-depth learning methods were used to construct the PM2.5 and O3 meteorological condition indexes based on long-term pollution meteorological observation data. A research method was developed to study the meteorological characteristics and impact contribution of atmospheric complex pollution by using the meteorological condition index, and quantitative analysis of the distribution and variation of pollution excluding the influence of regional meteorological differences was also conducted. The results showed that in the summer of 2021, the pollution meteorological conditions in the key regions in central and eastern China were generally worse in the north and better in the south(index:"2+26" cities>the border area of Jiangsu, Anhui, Shandong, and Henan>the Yangtze River Delta) and the worst in June and the best in July. The "double high" pollution began to appear when the PM2.5 meteorological condition index>30 and O3 meteorological condition index>100; meanwhile, the unfavorable meteorological conditions for O3 also promoted the increase in PM2.5 concentration, resulting in the frequency of "double high" increases with the increase in O3 meteorological condition index. Compared with that during the same period last year, ρ(PM2.5) of each region decreased by 3.9 µg·m-3, 3.3 µg·m-3, and 1.4 µg·m-3 due to the contribution of the improvement in the pollution meteorological conditions, which is nearly 58.5% on average of the total decrease in PM2.5 concentration. However, the change in O3 pollution meteorological conditions was better in the north and worse in the south, and the overall deterioration in the Yangtze River Delta Region led to approximately 2.8 µg·m-3 growth for the O3 concentration. The PM2.5 and O3 concentrations after excluding the impact of meteorological differences showed different distribution characteristics from the air quality monitoring, in which the high concentrations of PM2.5 were distributed along the Bohai Sea, the inter-provincial border, and the south of the region, whereas the high concentrations of O3 were concentrated along the Taihang Mountains, around Mount Tai, and in parts of the Yangtze River Delta. The daily concentration variations in a single city during a specific pollution control period could be used as a basis for evaluating the effectiveness of local supervision and control, which will provide a reference for the dynamic supervision and daily scheduling of local control management.

6.
Fitoterapia ; 158: 105142, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35124161

RESUMO

This is the first phytochemical investigation of Schisandra tomentella A. C. Smith. 11 lignans and 8 sesquiterpenoids, were isolated from the stems of S. tomentella, including two undescribed lignans, tomentaschinins A-B (1-2), and two new sesquiterpenoids, tomentaschinnes A-B (3-4). Their structures were elucidated based on the interpretation of their spectroscopic data. Cytotoxicity and MDR reversal effect of these compounds were screened on multidrug resistance cancer cell line MCF-7/ADR, and results showed gomisin M2 (7) could promote the efficacy of adriamycin against MCF-7/ADR.


Assuntos
Lignanas , Schisandra , Sesquiterpenos , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Schisandra/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia
7.
Chin J Integr Med ; 25(3): 203-209, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30552545

RESUMO

OBJECTIVE: To investigate the effects of Ganoderma lucidum polysaccharides (GL-PS) on human fibroblasts and skin wound healing in Kunming male mice and to explore the putative molecular mechanism. METHODS: Primary human skin fibroblasts were cultured. The viability of fibroblasts treated with 0, 10, 20, 40, 80, and 160 µg/mL of GL-PS, respectively were detected by 3-4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2-Htetrazolium bromide (MTT). The migration ability of fibroblasts treated with 0, 10, 20, and 40 µg/mL of GL-PS were measured by transwell assay. The secretion of the C-terminal peptide of procollagen type I (CICP) and transforming growth factor-ß1 (TGF-ß1) in the cell supernatant was tested by enzyme-linked immunosorbent assay. The expression of ß-catenin was detected by Western blot. Furthermore, the Kunming mouse model with full-layer skin resection trauma was established, and was treated with 10, 20, and 40 mg/mL of GL-PS, respectively as external use. The size of the wound was measured daily, complete healing time in each group was recorded and the percentage of wound contraction was calculated. RESULTS: Compared with the control group, 10, 20, and 40 µg/mL of GL-PS significantly increased the viability of fibroblasts, promoted the migration ability of fibroblasts, and up-regulated the expressions of CICP and TGF-ß1 in fibroblasts (Plt;0.05 or Plt;0.01). The expression of ß-catenin in fibroblasts treated with 20 and 40 µg/mL of GL-PS was significantly higher than that of the control group (Plt;0.01). Furthermore, after external use of 10, 20, and 40 mg/mL of GL-PS, the rates of wound healing in mice were significantly higher and the wound healing time was significantly less than the control group (Plt;0.05 or Plt;0.01). CONCLUSION: A certain concentration of GL-PS may promote wound healing via activation of the Wnt/ß-catenin signaling pathway and up-regulation of TGF-ß1, which might serve as a promising source of skin wound healing.


Assuntos
Polissacarídeos/farmacologia , Reishi/química , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/biossíntese , Fibroblastos/efeitos dos fármacos , Humanos , Masculino , Camundongos , Pele/lesões , Fator de Crescimento Transformador beta1/fisiologia , beta Catenina/fisiologia
8.
Colloids Surf B Biointerfaces ; 43(3-4): 198-202, 2005 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-15975773

RESUMO

The volatile oil of the roots of Cynanchum stauntonii was examined by gas chromatography-mass spectrometry (GC-MS). Thirty-eight constituents were identified. (E,E)-2,4-Decadienal, 3-efhyl-4-methypentanol, 5-pentyl-3H-furan-2-one, (E,Z)-2,4-decadienal and 2(3H)-furanone,dihydro-5-pentyl were found to be the major components. The volatile oil exhibited the activities against influenza virus in vitro (IC50s=64 microg/ml). In in vivo experiment, it prevented influenza virus-induced deaths in a dose-dependent manner.


Assuntos
Antivirais/farmacologia , Cynanchum/química , Orthomyxoviridae/efeitos dos fármacos , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Animais , Antivirais/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas , Vírus da Influenza A , Masculino , Camundongos , Infecções por Orthomyxoviridae/tratamento farmacológico , Raízes de Plantas/química , Ensaio de Placa Viral
9.
J Comp Neurol ; 193(3): 753-76, 1980 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-6160167

RESUMO

Horseradish peroxidase (HRP) was injected in ovo into the ventral muscle mass of the hind limb of 5- to 7-day-old chick embryos or into the gastrocnemius muscle of 8- to 18-day embryos and localized histochemically. HRP is extensively incorporated via endocytosis into axonal growth cones or presynaptic terminals in the proximity of the injection site. Much of the tracer is taken up in vesicles and small vacuoles. Most of these are smooth-surfaced and only a few are bristle-coated. A small amount of the tracer is also incorporated into the axon terminal through the openings between the axolemma and an intricate membrane channel. The majority of the tracer-laden vesicles and vacuoles rapidly fuse with one another to become large vacuoles, some of which are transformed into multivesicular bodies (MVBs). In axon shafts, many labeled vacuoles and MVBs are transferred to tubule-like organelles, which appear to be the primary carrier for transporting the tracer back to the cell bodies in the lumbar spinal cord. HRP arrives in the sensory ganglia about 0.5-1 hour earlier than in the motoneurons of the lateral motor column. The maximal rate of the retrograde axoplasmic transport is about 3.5 mm/hour. After arriving in the cell bodies, HRP is transferred from tubule-like organelles to discrete vacuoles of various sizes and appearance. Lysosomal dense bodies and HRP-labeled vacuoles can be distinguished ultrastructurally. A fusion of HRP-labeled vacuoles with lysosomal dense bodies or Golgi vesicles was occasionally observed and the density of HRP-labeled vacuoles diminished after 2 to 3 days. Most of the HRP-labeled organelles were found to contain acid phosphatase activity. Therefore, the complete disappearance of HRP by 4 days postinjection is most likely related to lysosomal degradation. Neuronal cell bodies diffusely labeled with HRP were only observed prior to day 6. After day 6, despite various attempts to injure the peripheral axons, only granularly labeled cell bodies were found. This difference may imply that "mature" neurons have a more efficient mechanism for the sequestration of "free" HRP in the cytoplasmic matrix into membrane-bounded organelles. A mature-like retrograde transport mechanism appears to exist at the earliest stages of axonal growth in vivo.


Assuntos
Transporte Axonal , Medula Espinal/embriologia , Animais , Axônios/ultraestrutura , Embrião de Galinha , Endocitose , Membro Posterior/inervação , Peroxidase do Rábano Silvestre/metabolismo , Lisossomos/ultraestrutura , Microscopia Eletrônica , Junção Neuromuscular/ultraestrutura , Neurônios/metabolismo , Vacúolos/ultraestrutura
10.
J Comp Neurol ; 161(3): 383-418, 1975 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1150915

RESUMO

We have quantitatively examined the development of synapses in the ventral part of the lumbar spinal cord of the chick from embryonic day 4 until adulthood. The first synapses occur on day 4 and are of the axo-dendritic type; they are invariably located adjacent to the border between the intermediate and marginal zones. Initially there are more synapses in the presumptive white matter than in the motoneuron neuropil, but this trend is later reversed; however, we found numerous axo-dendritic synapses throughout much of the ventrolateral white matter even in the adult stage. The first axo-dendritic synapses always contain spherical synaptic vesicles and have symmetric membrane specilizations. By day 7 a few of these synapses were found to have mixed populations of spherical and flattened vesicles and asymmetric membrane specilizations. After hatching there are still considerably more axo-dendritic synapses with symmetric membrane specializations. Axo-somatic synapses were first found on embryonic day 6 and were typically located on motoneurons lying adjacent to the marginal zone. These axo-somatic synapses contain a few spherical synaptic vesicles and have symmetric membrane densities. Flattened synaptic vesicles were first found on day 10 and increased throughout development. Although a few axo-somatic synapses with asymmetric membrane specializations were found at practically all stages, the symmetric type was always in the majority. An attempt was made to relate these observations with physiological, behavioral and neuroembryological findings from birds and other forms. For example, the fact that axo-dendritic synapses always appear prior to axo-somatic contacts would seem to rule out the role of somatic synapsesin the initial induction of dendritic growth in the spinal cord.


Assuntos
Medula Espinal/embriologia , Sinapses/ultraestrutura , Fatores Etários , Animais , Contagem de Células , Embrião de Galinha , Interneurônios/citologia , Neurônios Motores/citologia , Vias Neurais , Medula Espinal/citologia , Medula Espinal/ultraestrutura , Membranas Sinápticas/ultraestrutura , Vesículas Sinápticas/ultraestrutura
11.
Brain Res ; 213(2): 307-18, 1981 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-6972797

RESUMO

Motoneurons in the course of migration to the lateral motor column (LMC) were identified by horseradish peroxidase (HRP) applied to lumbar ventral roots in anuran larvae (Rana catesbeiana). The ultrastructural characteristics of these migrating motoneurons were compared with motoneurons in the LMC that had completed their migration. Both migrating and LMC motoneurons tended to be bipolar with one process extending toward the ependyma and the other out towards the ventral root. Typically, centrally and peripherally directed processes in both migrating and LMC motoneurons contained many microtubules, mitochondria and rosette-like clusters of ribosomes, as did the soma. Four of the five types of synapses found on adult frog motoneurons were also found on migrating motoneurons in tadpoles. Radial glia, whose cell bodies are located in the ependyma, have processes extending to the spinal cord periphery. In less than 10% of the preparations, radial glia were labeled with the HRP reaction product. These labeled glia were further distinguished from migrating motoneurons at the ultrastructural level by the presence of abundant filaments.


Assuntos
Neurônios Motores/fisiologia , Medula Espinal/citologia , Animais , Movimento Celular , Núcleo Celular/ultraestrutura , Larva , Microscopia Eletrônica , Neurônios Motores/ultraestrutura , Neuroglia/ultraestrutura , Rana catesbeiana , Medula Espinal/ultraestrutura , Sinapses/ultraestrutura
12.
Tissue Cell ; 7(2): 331-46, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1145610

RESUMO

The sensory organs on the tarsi of the antenniform first legs of the whip spider Admetus pumilio C. L. Koch (Amblypygi, Arachnida) were examined with the scanning and transmission electron microscope. At least four different types of hair sensilla were found: (1) thick-walled bristles, which have the characteristics of contact chemoreceptors (several chemoreceptive dendrites in the lumen plus two mechanoreceptors at the base); (2) short club sensilla, innervated by 4-6 neurons which terminate in a pore on the tip; they are possibly humidity receptors; (3) porous sensilla, which are either innervated by 20-25 neurons and have typical pore tubules, or they have 40-45 neurons but no pore tubules; both types are considered to be olfactory; (4) rod sensilla occur in clusters near segmental borders; they are innervated by only one large dendrite which branches inside the lumen. Other tarsal receptors are the claws, which correspond to contact chemoreceptors, and the pit organ which resembles the tarsal organ of spiders. Compared to other arthropod sensilla, the contact chemoreceptors are very similar to those of spiders, while the porous sensilla correspond structurally to olfactory receptors in insects; the club and rod sensilla seem to be typical for amblypygids.


Assuntos
Células Receptoras Sensoriais/ultraestrutura , Aranhas/ultraestrutura , Animais , Cílios/ultraestrutura , Dendritos/ultraestrutura , Extremidades/inervação , Mecanorreceptores/ultraestrutura , Microtúbulos/ultraestrutura , Receptores de Droga , Aranhas/anatomia & histologia , Tarso Animal/inervação
13.
Colloids Surf B Biointerfaces ; 36(2): 105-9, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15261014

RESUMO

In this paper, an appropriate scale screening for traditional Chinese medicine formula was developed in according to verified pharmacological experiments with uniform optimized experimental design and orthogonal optimized experimental design. Meanwhile, a most appropriate match of prescription dosage for curing vascular disease was got, which was based on NO value of pharmacodynamics experimental data and the endothelial cells configuration which would changed in a degree when damaged by hydration diamine. The appropriate scale of the formula was Ginkgo extraction: substance A:B:C = 100:20:50:0.01. This formula was more optimized and effective than other formula compared by pharmacological and validated experiments.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Projetos de Pesquisa , Células Cultivadas , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Endotélio Vascular/efeitos dos fármacos , Ginkgo biloba/química , Nitratos/análise , Nitratos/metabolismo , Nitritos/análise , Nitritos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Reprodutibilidade dos Testes , Doenças Vasculares/tratamento farmacológico
14.
ACS Appl Mater Interfaces ; 4(10): 5643-9, 2012 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23009200

RESUMO

In recent years, the synergistic effects of Au-based hybrids have generated enormous scientific interest. The hybrids of Au and Co are expected to exhibit attractive properties. In this paper, we report the successful fabrication of the nanohybrids between bulk-immiscible Au and Co with chain-like structures via a mild solution method. Elemental mapping, XRD and EXAFS data reveal that the as-prepared AuCo nanohybrids might be of cluster mixed configuration. A sequential redox and imperfection-promoted aggregation/diffusion process is proposed to elucidate the formation mechanism of the nanohybrids. The as-prepared products exhibit a temperature-independent saturation magnetization with the magnetic moment of Co as high as ~2.95 µ(B) for each Co atom at 300 K, much higher than the bulk value (~1.7 µ(B) for each Co atom) and approaching the theoretical value of an atomic Co (~3.0 µ(B) for each Co atom).

15.
Nanoscale ; 3(6): 2458-60, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21566828

RESUMO

Reduced graphene oxide (RGO) was synthesized under H(2)/Ar treatment from 100 °C to 900 °C. RGO-300 shows excellent sensitivity to H(2) and a dual sensing mode was observed. The balance between the chemical adsorption capacity and electronic conductivity, and the dominance of either electrons or holes are the key factors.


Assuntos
Ar/análise , Grafite/química , Hidrogênio/análise , Óxidos/química , Adsorção , Condutividade Elétrica , Monitoramento Ambiental , Explosões/prevenção & controle , Hidrogênio/química , Oxirredução , Temperatura
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