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1.
Molecules ; 28(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37175205

RESUMO

Glioblastoma (GBM) is the most aggressive brain tumor, with high mortality. Timosaponin AIII (TIA), a steroidal saponin isolated from the medicinal plant Anemarrhena asphodeloides Bge., has been shown to possess anticancer properties in various cancer types. However, the effect of TIA on GBM is unknown. In this study, we reveal that TIA not only inhibited U87MG in vitro cell growth but also in vivo tumor development. Moreover, we found that the cause of TIA-induced cell growth suppression was apoptosis. When seeking to uncover antitumor mechanisms of TIA, we found that TIA diminished the expression of cGMP-specific phosphodiesterase 5(PDE5) while elevating the levels of guanylate cyclases (sGCß), cellular cGMP, and phosphorylation of VASPser239. Following the knockdown of PDE5, PDE5 inhibitor tadalafil and cGMP analog 8-Bro-cGMP both inhibited cell growth and inactivated ß-catenin; we reason that TIA elicited an antitumor effect by suppressing PDE5, leading to the activation of the cGMP signaling pathway, which, in turn, impeded ß-catenin expression. As ß-catenin is key for cell growth and survival in GBM, this study suggests that TIA elicits its anti-tumorigenic effect by interfering with ß-catenin function through the activation of a PDE5/cGMP functional axis.


Assuntos
Glioblastoma , beta Catenina , Humanos , beta Catenina/metabolismo , Glioblastoma/tratamento farmacológico , Esteroides/farmacologia , Apoptose , Transdução de Sinais , GMP Cíclico/metabolismo
2.
Medicina (Kaunas) ; 59(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36837411

RESUMO

Objective To evaluate the effectiveness of music therapy for dental anxiety disorders. Methods In order to gather clinical randomized controlled trials comparing the effectiveness of music interventions to traditional oral manipulation in patients with dental anxiety disorders, computer searches of the electronic databases of Wanfang, CNKI, VIP, PubMed, Web of Science, ScienceDirect, Cochrane library, Scopus, and CINAHL were conducted. The search period covered from 23 December 2022, through to the development of the database. The Cochrane Handbook was used to assess the quality of the included literature, and two researchers independently conducted the literature screening and data extraction. Stata 17.0 and RevMan 5.3 were used to conduct the meta-analysis. Results The preoperative baseline levels of the music intervention group were similar to those of the control group (p > 0.05), according to the meta-analysis, and music intervention significantly decreased heart rate (I2 = 81.2%, WMD (95% CI): -7.33 (-10.07, -4.58), p < 0.0001), systolic blood pressure fluctuations (I2 = 85.6%, WMD (95% CI): -6.10(-9.25, 2.95), p < 0.0001), diastolic blood pressure (I2 = 79.7%, WMD (95% CI): -4.29(-6.57, -2.02), p < 0.0001) fluctuations, anxiety scores (I2 = 19.6%, WMD (95% CI): -9.04(-11.45, 6.63), p < 0.0001), and pain scores (I2 = 32.7%, WMD (95% CI): -7.64(-9.43, -5.85), p < 0.0001), as well as significantly lowered anxiety and pain levels and raised patients' cooperation rates (I2 = 0%, OR (95% CI): 3.03(1.24, 7.40), p = 0.02). Conclusions Music interventions are effective for dental anxiety disorders, but given the limitations of the study, more multicenter, large-sample, high-quality randomized controlled trials are needed to further validate the findings and obtain more objective and reliable clinical evidence.


Assuntos
Musicoterapia , Música , Humanos , Musicoterapia/métodos , Ansiedade/prevenção & controle , Transtornos de Ansiedade , Dor , Estudos Multicêntricos como Assunto
3.
Am J Bot ; 110(6): e16147, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36827179

RESUMO

PREMISE: Co-flowering species that have not evolved an avoidance mechanism may have tolerance to heterospecific pollen (HP) deposition as an adaptive strategy to minimize any deleterious effects of HP transfer, but empirical evidence for the tolerance hypothesis remains scarce. METHODS: To estimate the potential effects of heterospecific pollen deposition (HPD) on female reproductive success, we counted conspecific (CP) and HP pollen grains deposited on stigmas and assessed subsequent seed set of both open- and hand-pollinated flowers in three co-flowering Silene species with exposed stigmas that usually received numerous HP grains on the elongated receptive area. RESULTS: The percentage of HP grains per flower (HP%) varied from 16.6% to 43.0% among three species. Silene chungtienensis had lower HP%, and the CP-HP relationship was neutral; S. gracilicaulis and S. yunnanensis had a relatively higher HP% with a positive CP-HP relationship. The effects of CP and HP number on natural seed set were positive for all three species, but HP% had stronger negative effects in S. chungtienensis and S. gracilicaulis. In hand-pollinated flowers of the three Silene species, seed set did not decrease with HP whether CP was in excess or insufficient, indicating no negative effects of HPD on seed production. CONCLUSIONS: Consistent with the tolerance hypothesis, our results indicated that species with higher HP interference are likely to be tolerant to an increase in HP%. These species with generalist-pollinated flowers and exposed large stigmas may benefit from an increase of conspecific pollen deposition, despite the associated increase in heterospecific pollen deposition.


Assuntos
Polinização , Silene , Pólen , Reprodução , Sementes , Flores
4.
Am J Bot ; 110(1): e16113, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36462154

RESUMO

PREMISE: Why have pollen grains evolved to be exceptionally large in some species? Pollen-feeding hypothesis suggests that if the proportion of pollen amounts for feeding is reduced in a flower, the low allocation to pollen number would allow pollen grains to be larger. METHODS: To examine whether species with large pollen grains experience low pollen consumption, the behavior of insects feeding on nectar and pollen was observed and pollen transfer efficiency was estimated for four visitor types in Geranium delavayi. To see whether bees actively collected pollen, the numbers of grains in pollen baskets and on the body were compared. Both nutritional value (total protein and lipid) and chemical defense (phenolic metabolites) in pollen against pollen feeders were measured. RESULTS: Bumblebees and honeybees foraged for nectar, rarely groomed pollen into corbiculae, and had >5× higher pollen transfer efficiency than smaller solitary bees and flies, which were pollen eaters that removed more pollen but deposited less. Pollen grains were characterized by low protein and high lipid content with a low protein-lipid ratio, an unfavorable combination for bumblebees. Three secondary metabolites were significantly higher in pollen grains (7.77 mg/g) than in petals (1.08 mg/g) or in nectar (0.44 mg/g), suggesting stronger chemical defense in pollen. CONCLUSIONS: Our results indicated that large bees took nectar but little of the nutritionally poor and highly toxic pollen. These data support one prediction of the pollen-feeding hypothesis, that species with few and large pollen grains would also have low pollen-consumption rates.


Assuntos
Geranium , Néctar de Plantas , Abelhas , Animais , Flores , Insetos , Comportamento Alimentar , Pólen/química , Lipídeos/análise , Polinização
5.
Elife ; 112022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36217820

RESUMO

Animal-pollinated plants have to get pollen to a conspecific stigma while protecting it from getting eaten. Touch-sensitive stamens, which are found in hundreds of flowering plants, are thought to function in enhancing pollen export and reducing its loss, but experimental tests are scarce. Stamens of Berberis and Mahonia are inserted between paired nectar glands and when touched by an insect's tongue rapidly snap forward so that their valvate anthers press pollen on the insect's tongue or face. We immobilized the stamens in otherwise unmodified flowers and studied pollen transfer in the field and under enclosed conditions. On flowers with immobilized stamens, the most common bee visitor stayed up to 3.6× longer, yet removed 1.3× fewer pollen grains and deposited 2.1× fewer grains on stigmas per visit. Self-pollen from a single stamen hitting the stigma amounted to 6% of the grains received from single bee visits. Bees discarded pollen passively placed on their bodies, likely because of its berberine content; nectar has no berberine. Syrphid flies fed on both nectar and pollen, taking more when stamens were immobilized. Pollen-tracking experiments in two Berberis species showed that mobile-stamen-flowers donate pollen to many more recipients. These results demonstrate another mechanism by which plants simultaneously meter out their pollen and reduce pollen theft.


Assuntos
Néctar de Plantas , Polinização , Animais , Abelhas , Flores , Plantas , Pólen , Tato
6.
Int J Biol Macromol ; 219: 597-610, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-35952811

RESUMO

The treatment of drug-resistant bacterial infections attributed to the overuse of antibiotics still remains a serious challenge globally. Herein, zwitterionic charge switchable meso-silica/polypeptide hybrid nanoparticles (MSPNs) were prepared for the synergistic chemo-photodynamic therapy in the treatment of drug-resistant bacterial infections. Subsequently, azithromycin (AZT) and methylene blue (MB) were loaded in the MSPNs to form the combined chemo-photodynamic therapeutic nanoparticles (MSPNs-AZT/MB) for the treatment of methicillin-resistant Staphylococcus aureus (MRSA). Remarkably, the as-prepared MSPNs-AZT/MB exhibited a negative surface charge of -5.2 mV at physiological pH while switching into positive surface charge of 24.7 mv in an acidic environment, leading to enhanced binding with bacterial surface. The lipase-triggered AZT release up to 77.9 % was achieved, and the loaded MB demonstrated efficient singlet oxygen (1O2) generation for photodynamic therapy. The in vitro experimental results displayed an excellent antibacterial effect against MRSA in both planktonic and biofilm phenotypes. Additionally, the as-prepared MSPNs-AZT/MB exhibited synergistic and enhanced antibacterial infection effect up to 94 % comparing to monotherapy in a mice model. Considering the above advantages, the as-prepared combined chemo-photodynamic therapeutic nanoparticles showed promising biocompatibility and clinical potential for the efficient therapy of drug-resistant bacteria.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Fotoquimioterapia , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Azitromicina/farmacologia , Azitromicina/uso terapêutico , Lipase/farmacologia , Azul de Metileno/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Dióxido de Silício/farmacologia , Oxigênio Singlete , Infecções Estafilocócicas/tratamento farmacológico
7.
ACS Sens ; 6(11): 4108-4117, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34757732

RESUMO

Tongue is a unique organ that senses tastes, and the scientific puzzle about whether electricity can evoke taste sensations and how the sensations have been distributed on the tongue has not been solved. Investigations on tongue stimulation by electricity might benefit the developments of techniques for clinical neuromodulation, tissue activation, and a brain-tongue-machine interface. To solve the scientific puzzle of whether electrical stimulation induces taste-related sensations, a portable flexible tongue electrode array system (FTEAS) was developed, which can synchronously provide electrical stimulation and signal mapping at each zone of the tongue. Utilizing the FTEAS to perform tests on the rat tongue in vivo, specific electrical signals were observed to be evoked by chemical and electrical stimulations. The features and distributions of the electric signals evoked during the rat tongue tests were systematically studied and comprehensively analyzed. The results show that an appropriate electrical stimulation can induce multiple sensations simultaneously, while the distribution of each sensation was not significantly distinguished among different zones of the tongue, and at the same time, this taste-related electrical signal can be recorded by the FTEAS. This work establishes a promising platform to solve the scientific puzzle of how sensations are activated chemically and electrically on the tongue and may provide advanced noninvasive oral-electrotherapy and a brain-tongue-machine interface.


Assuntos
Paladar , Língua , Estimulação Elétrica , Eletricidade , Eletrodos
8.
Colloids Surf B Biointerfaces ; 207: 112014, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34391166

RESUMO

Combined chemo-photothermal therapy of gold nanorods (GNRs) for cancer treatment shows better therapeutic efficiency than mono-chemotherapy, which has gained worldwide interests of scientists and clinician in both laboratory and clinic application. However, high cytotoxicity, declined delivery efficiency, and unsatisfactory therapy effect of the GNRs are still challenging in anti-cancer treatment. Herein, a series of pH-sensitively zwitterionic polypeptide conjugated GNRs were synthesized via a gold-thiol interaction for combination of chemo-photothermal therapy in cervical cancer treatment. The acid-labile hydrazone bond was utilized to incorporate the doxorubicin (DOX) for pH-sensitive drug release under tumoral environment. The as prepared GNRs conjugates demonstrated pH-triggered surface charge conversion from negative to positive when transporting from blood circulation to tumor extracellular environment, which can facilitate the cellular uptake via electrostatic interaction. After cellular internalization, the drug release was promoted by cleavage of the hydrazone in GNRs conjugates under cancer intracellular acid environment. As the effective near-infrared (NIR) photothermal materials, the as prepared GNRs conjugates can absorb NIR photo energy and convert it into heat under irradiation, which can efficiently kill the tumor cells. In cell assay, the GNRs conjugates displayed excellent biocompatibility against normal cell, enhanced cancer cell uptake, and remarkable cancer cell killing effects. In HeLa tumor-bearing mice, the GNRs conjugates demonstrated enhanced tumor inhibition efficacy by combination of chemo-photothermal therapy.


Assuntos
Nanotubos , Neoplasias do Colo do Útero , Animais , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Feminino , Ouro , Humanos , Camundongos , Peptídeos , Fototerapia , Terapia Fototérmica , Neoplasias do Colo do Útero/terapia
9.
Am J Bot ; 107(9): 1274-1282, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32895943

RESUMO

PREMISE: It has been hypothesized that pollination success in animal-pollinated dioecious plants relies on opportunistic pollinators with no discrimination against female flowers. However, empirical studies of pollinator foraging behavior and pollination effectiveness in dioecious species are few. METHODS: To investigate potential pollinators in Helwingia japonica, a dioecious shrub with small, inconspicuous flowers, we compared floral visitors and visit frequency to female and male plants for three flowering seasons in two field populations in subtropical forests in southwest China. Pollen placement on the insect bodies of four groups (solitary bees and other bees, fungus gnats, and other flies) was compared, and insect foraging behavior was observed. Pollen removal and conspecific and heterospecific pollen deposition per visit were measured to compare pollination effectiveness among the four groups. RESULTS: Floral visitors usually did not discriminate between male and female flowers and did not gather pollen into collections. Our measurements of pollen transfer efficiency showed that solitary bees were the most effective pollinators with the highest conspecific pollen deposition. These insects seemed to be opportunistic visitors because pollen grains of H. japonica were distributed evenly over different regions of the visitor's body, and heterospecific pollen accounted for over 50% of total pollen loads on stigmas in the two populations. CONCLUSIONS: Our investigations indicated that potential pollinators were generalists and did not discriminate against female flowers, as predicted for dioecious species pollinated by insects. A perspective of pollen removal by floral visitors offers insights into the evolution of plant sexual systems.


Assuntos
Insetos , Polinização , Animais , Abelhas , China , Feminino , Flores , Masculino , Pólen
10.
Proc Biol Sci ; 287(1933): 20201191, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32811305

RESUMO

Angiosperm pollen grain diameter varies greatly from a few microns to over 100, but the selective forces driving the interspecific variation in pollen size remain unclear. Although both pre- and post-pollination hypotheses have been proposed, empirical evidence remains scarce. Here we propose that visits by pollen-foraging pollinators have selected against large pollen grains. An association between pollinator behaviour and pollen grain size was confirmed by field studies of 80 flowering species in natural communities, showing that pollinators positively collected pollen in those species with relatively smaller pollen grains but rarely did so in species with larger ones. Allowing for the confounding effects of pollinator type, flower size or style length and pollen grain number, we found a significant effect of pollen-foraging behaviour on variation in pollen grain size, particularly in bee-pollinated plants. While these results suggest that many plant species whose pollen is collected or consumed by pollinators produce small pollen grains, it remains unclear whether pollen grain size is directly affected by pollinator foraging habit or indirectly mediated by pollen number trade-offs.


Assuntos
Magnoliopsida , Pólen , Polinização , Animais , Abelhas , Comportamento Alimentar , Flores
11.
J Bone Miner Res ; 35(6): 1014-1021, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31999376

RESUMO

Recent studies suggest that the RANK/RANKL system impacts muscle function and/or mass. In the pivotal placebo-controlled fracture trial of the RANKL inhibitor denosumab in women with postmenopausal osteoporosis, treatment was associated with a lower incidence of non-fracture-related falls (p = 0.02). This ad hoc exploratory analysis pooled data from five placebo-controlled trials of denosumab to determine consistency across trials, if any, of the reduction of fall incidence. The analysis included trials in women with postmenopausal osteoporosis and low bone mass, men with osteoporosis, women receiving adjuvant aromatase inhibitors for breast cancer, and men receiving androgen deprivation therapy for prostate cancer. The analysis was stratified by trial, and only included data from the placebo-controlled period of each trial. A time-to-event analysis of first fall and exposure-adjusted subject incidence rates of falls were analyzed. Falls were reported and captured as adverse events. The analysis comprised 10,036 individuals; 5030 received denosumab 60 mg subcutaneously once every 6 months for 12 to 36 months and 5006 received placebo. Kaplan-Meier estimates showed an occurrence of falls in 6.5% of subjects in the placebo group compared with 5.2% of subjects in the denosumab group (hazard ratio = 0.79; 95% confidence interval 0.66-0.93; p = 0.0061). Heterogeneity in study designs did not permit overall assessment of association with fracture outcomes. In conclusion, denosumab may reduce the risk of falls in addition to its established fracture risk reduction by reducing bone resorption and increasing bone mass. These observations require further exploration and confirmation in studies with muscle function or falls as the primary outcome. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research..


Assuntos
Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Neoplasias da Próstata , Acidentes por Quedas , Antagonistas de Androgênios , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Denosumab/uso terapêutico , Humanos , Incidência , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Biol Lett ; 15(10): 20190479, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31662065

RESUMO

Bees are often considered to be effective pollinators in both agricultural and natural ecosystems but could be ineffective pollinators in that they collect large quantities of pollen for food provision but deliver little to stigmas. Male bees do not collect pollen to feed larvae, and their pollination role has been underappreciated. Here we compare pollination effectiveness, visit frequency and pollen foraging behaviour between female and male individuals of a mining bee, Andrena emeishanica, visiting a nectariferous spring flower (Epimedium pubescens). Female bees were observed to forage for both pollen and nectar, but male bees foraged only for nectar. Female bees had large hairy hind tibiae with conspicuous scopae, and nearly 90% of the pollen grains they collected went onto the hind legs. Male bees removed less pollen from anthers than female bees but deposited more pollen on stigmas per visit. The higher pollen transfer efficiency of male bees was due to 48.4% of pollen grains remaining ungroomed on the thorax and abdomen, available for stigma contact, but their visitation rate to flowers was much lower. Our results indicate that male solitary bees could transfer more pollen on the stigma per visit but were less important (transferred less pollen in total, because they made fewer visits per unit time) than females.


Assuntos
Ecossistema , Polinização , Animais , Abelhas , Feminino , Flores , Masculino , Pólen , Estações do Ano
13.
New Phytol ; 224(3): 1142-1150, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31225909

RESUMO

Visual signals attractive to friends may also attract enemies.  The bright colors of anthers and pollen have generally been thought to attract pollinators. We hypothesize that visual crypsis of anthers, and particularly pollen, should be favored in flowering plants because protection from pollen collectors reduces the loss of male gametes. To understand adaptive strategies relating to the color of pollen, we measured the color of pollen, undehisced anther sacs, and their background, the corolla, with a spectrometer for 104 insect-pollinated flowering species from a natural community in Hengduan Mountains, southwest China. The colors of anthers, pollen and corollas were diverse in these species. The color diversity of exposed pollen was significantly higher than that of concealed pollen (i.e. where anthers are enclosed or shielded by corollas). The color contrast between pollen and corolla was significantly smaller in species with exposed pollen than in those with concealed pollen. Unlike anther color, exposed pollen color tended to match its background corolla color. Our phylogenetic comparative analysis showed contrasting effects of pollen color patterns between flowers with exposed pollen and those with concealed pollen, revealing a strategy of hiding pollen from pollen thieves via visual crypsis.


Assuntos
Flores/fisiologia , Pigmentação , Pólen/fisiologia , Cor , Modelos Lineares , Filogenia , Análise de Componente Principal , Especificidade da Espécie
14.
Curr Biol ; 29(8): 1401-1406.e4, 2019 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-30982649

RESUMO

Many bees are effective pollen collectors; however, pollen grains collected by bees for larval food are lost for plant sexual reproduction. Recognition of these conflicting interests between bees and flowers is essential for understanding of reproduction for both bees and flowers [1-3]. Plant defense compounds in pollen may function to reduce pollen waste by deterring ineffective pollinators [4-6], but this hypothesis remains unexamined. Here, we provide evidence that secondary metabolites in pollen function as chemical defense by deterring some bees from gathering pollen. In two Dipsacus species, a defense compound, dipsacus saponin [7], occurs in pollen but not in nectar. We observed that bumblebees disliked grooming bitter-tasting pollen with a high saponin content. Manipulation of saponin concentrations in nectar and measurements of corbicular pollen showed that the bumblebee species differed in their tolerance to saponin. Those species susceptible to saponin groomed little Dipsacus pollen into their pollen loads, and their ungroomed pollen was observed to be effectively delivered to stigmas. By rewarding bees with edible nectar, but not pollen, plants solve the conflict of pollen partitioning between sexual and reward functions. Ungroomed toxic pollen on the bee body promotes pollen transfer efficiency, facilitating pollination.


Assuntos
Abelhas/fisiologia , Dipsacaceae/química , Pólen/toxicidade , Polinização , Saponinas/toxicidade , Animais , Abelhas/efeitos dos fármacos , Néctar de Plantas/química , Néctar de Plantas/toxicidade , Pólen/química
15.
New Phytol ; 221(2): 1150-1159, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30121952

RESUMO

Pollen grains can be dispersed singly or variously aggregated in groups. Whether the evolution of pollen aggregation is driven by the pollinator remains unexplored. We hypothesize that an extensive pollen aggregation is favored under a scarcity of pollinators. Variation in pollen aggregation by viscin threads in 13 Rhododendron species was measured as it is related to pollen removal in a visit. Visitation rates of functional pollinator groups that vary in their grooming behavior were investigated in each species. Pollen deposited on stigmas in the field was also sampled. Seven Rhododendron species were infrequently pollinated by low-intensity grooming animals, including birds, butterflies and moths. The other six species were more frequently pollinated by bees with a high intensity of pollen grooming. Bird- and Lepidoptera-pollinated species produced longer pollen-connecting threads that connected more pollen grains. Phylogenetically independent contrast analysis of the 13 species showed that pollinator visitation frequency was negatively related to amounts of pollen removal per visit but not to stigmatic pollen loads. The finding of interspecific patterns in pollen removal related to pollinator visitation frequency suggests pollinator-mediated selection on pollen packaging strategies, supporting the hypothesis of floral evolution via pollen export.


Assuntos
Abelhas/fisiologia , Borboletas/fisiologia , Mariposas/fisiologia , Rhododendron/fisiologia , Animais , Flores/fisiologia , Pólen/fisiologia , Polinização , Reprodução
16.
J Exp Clin Cancer Res ; 37(1): 243, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30285892

RESUMO

BACKGROUND: Licorice is an herb extensively used for both culinary and medicinal purposes. Various constituents of licorice have been shown to exhibit anti-tumorigenic effect in diverse cancer types. However, majority of these studies focus on the aspect of their growth-suppressive role. In this study, we systematically analyzed known licorice's constituents on the goal of identifying component(s) that can effectively suppress both cell migration and growth. METHODS: Effect of licorice's constituents on cell growth was evaluated by MTT assay while cell migration was assessed by both wound-healing and Transwell assays. Cytoskeleton reorganization and focal adhesion assembly were visualized by immunofluorescence staining with labeled phalloidin and anti-paxillin antibody. Activity of Src in cells was judged by western blot using phosphor-Src416 antibody while Src kinase activity was measured using Promega Src kinase assay system. Anti-tumorigenic capabilities of isoliquiritigenin (ISL) and 2, 4, 2', 4'-Tetrahydroxychalcone (THC) were investigated using lung cancer xenograft model. RESULTS: Using a panel of lung cancer cell lines, ISL was identified as the only licorice's constituent capable of inhibiting both cell migration and growth. ISL-led inhibition in cell migration resulted from impaired cytoskeleton reorganization and focal adhesion assembly. Assessing the phosphorylation of 141 cytoskeleton dynamics-associated proteins revealed that ISL reduced the abundance of Tyr421-phosphorylation of cortactin, Tyr925- and Tyr861-phosphorylation of FAK, indicating the involvement of Src because these sites are known to be phosphorylated by Src. Enigmatically, ISL inhibited Src in cells while displayed no effect on Src activity in cell-free system. The discrepancy was explained by the observation that THC, one of the major ISL metabolite identified in lung cancer cells abrogated Src activity both in cells and cell-free system. Similar to ISL, THC deterred cell migration and abolished cytoskeleton reorganization/focal adhesion assembly. Furthermore, we showed both ISL and THC suppressed in vitro lung cancer cell invasion and in vivo tumor progression. CONCLUSION: Our study suggests that ISL inhibits lung cancer cell migration and tumorigenesis by interfering with Src through its metabolite THC. As licorice is safely used for culinary purposes, our study suggests that ISL or THC may be safely used as a Src inhibitor.


Assuntos
Chalconas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Actinas/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Progressão da Doença , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/farmacologia , Adesões Focais/efeitos dos fármacos , Glycyrrhiza/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Extratos Vegetais/farmacologia , Distribuição Aleatória , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases da Família src/metabolismo
17.
Am J Bot ; 105(1): 108-116, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29532921

RESUMO

PREMISE OF THE STUDY: Heterostyly, the reciprocal positioning of stigmas and anthers in different floral morphs, has long been thought to promote intermorph pollination. However, extensive intramorph pollination occurs commonly in heterostylous species, leading to recurrent questions about the functional and evolutionary significance of heterostyly. METHODS: To identify the sources of stigmatic pollen (autogamous [intraflower], geitonogamous [intraplant], vs. interplant), we emasculated either one flower or entire plants in experimental populations of the two closely related buckwheat species, distylous Fagopyrum esculentum and homostylous F. tataricum. Differences in pollen size allowed unambiguous identification of pollen on stigmas. RESULTS: Only 2.4% of F. tataricum pollen and 1.5% of F. esculentum pollen arrived successfully on compatible stigmas of other plants. In the former (homostylous) species, 71.3% of the pollen load on stigmas was autogamous, 10.8% was geitonogamous, and 17.9% was interplant. In the latter (distylous) species, 37.45% of the pollen on stigmas was autogamous, 13.8% was geitonogamous, 17.0% was intramorph, and 31.75% was intermorph. The amount of incompatible pollen arriving on stigmas was greatly decreased by both one-flower and whole-plant emasculations, and thus, the proportion of compatible pollen deposited increased with one-flower emasculation and increased even more with whole-plant emasculation. CONCLUSIONS: Our quantification of pollen-donor sources in these two species indicated that heterostyly in Fagopyrum esculentum provided a nearly 2-fold fitness advantage (in terms of compatible pollination) over expected (random) pollen transfers between morphs. Because of reduced herkogamy, the homostylous F. tataricum was highly autogamous.


Assuntos
Fagopyrum/fisiologia , Flores/fisiologia , Pólen/fisiologia , Polinização
18.
Oecologia ; 186(1): 163-171, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29134400

RESUMO

Plant stigmas and bee pollinators are competitors for pollen. Pollen placed on a pollinator's body can be picked up by conspecific stigmas or it can be collected by the pollinator as food. Hypothetically, one solution is for pollen to be placed on 'safe sites' on the pollinator's body, sites where the pollinator cannot easily remove it, leaving the pollen for stigmas. We compared 14 sites on the bumblebee body in terms of the ability of the bee to groom off fluorescent power, a dust that may be thought of as analogous to pollen. The safest sites were along the midline of the dorsal thorax, the dorsal abdomen, and the ventral abdomen. Next, we counted how much pollen is borne on the 14 sites by bees visiting one nectariferous and three nectarless Pedicularis species. In the four species, only 7, 26, 28, and 30% of pollen found on the bees were on safe sites. Finally, we observed that the 14 sites were contacted by stigmas of the four Pedicularis species; none of the most contacted sites were safe sites. Across all four Pedicularis species, pollen is mainly positioned on sites of the bee body that were beneficial for both the plant and the bee, not on sites detrimental to either of them. Our analysis showed that the conflict of interest between flowers and bees can be solved by cooperation. Pedicularis pollen is placed where it strengthens the mutualism between plants and pollinators.


Assuntos
Pedicularis , Polinização , Animais , Abelhas , Conflito de Interesses , Flores , Pólen
19.
Oncotarget ; 8(48): 83723-83733, 2017 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-29137377

RESUMO

PURPOSE: To evaluate the effectiveness of nutrition intervention during radiation for patients with locoregionally advanced (III-IVa) nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: We retrospectively reviewed 117 patients with locoregionally advanced (III-IVa) NPC treated between December 2015 and March 2016 in Zhejiang Cancer Hospital. All the patients underwent radical chemo-radiotherapy. First, all the patients were divided into the nutrition intervention group and the control group, depending on whether they accepted nutrition intervention. Repeated measures were used to analyze the change of nutritional indicators before, during, and after radiation therapy and to simultaneously compare the difference in nutritional status between the two groups at the same time point. Subsequently, the 117 patients were divided into the malnourished group (weight loss > 5%) and the non-malnourished group (weight loss ≤ 5%) according to whether their weight loss was over 5% of their body weight during radiotherapy. Chi-square tests and logistic regression analysis were used to explore the influence factors for the weight loss. RESULTS: The repeated measures showed that all indicators including weight, body mass index (BMI), albumin, pre-albumin(PA), and prognostic nutritional index (PNI) dramatically declined in both groups compared with their levels before radiation therapy (All p < 0.001). However, there was no significant difference between the intervention and non-intervention groups regarding the mean values of nutritional indicators at the same time point, that before, during, and after radiation therapy, except BMI (All p > 0.05). Logistic regression analysis revealed grade ≥ 3 radiation-induced oral mucositis as the prognostic factor for a poor nutrition status (odds ratio, OR = 3.232, p = 0.021, confidence interval, CI [1.198, 8.820]). Besides this, patients with a decrease of >15% in pre-albumin level were more likely to be malnourished (OR = 2.442, p = 0.041, CI [1.036, 5.757]). Similar to that observed in our former analysis, we did not find that existing nutrition intervention can significantly improve nutritional status (OR = 1.217, p = 0.704, CI [0.042, 3.348]). CONCLUSIONS: Our study shows that the nutritional status of the patients gradually declined during treatment. We concluded that grade ≥ 3 radiation-induced oral mucositis would aggravate the extent of malnutrition during radiation therapy in patients with locoregionally advanced NPC. Pre-albumin level was a predictive marker for weight loss in patients with NPC. However, current nutrition intervention during radiation therapy can't significantly reverse nutritional status.

20.
Ecology ; 97(8): 1970-1978, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27859194

RESUMO

Pollinators visiting multiple plant species may cause heterospecific pollen transfer (HPT). To test a null model that more pollinator interspecific moves result in higher HPT among interacting species, we quantified the comparative magnitudes of the two networks involving 14 co-flowering species in an alpine meadow in the eastern Himalaya, southwest China. Interspecific moves accounted for 4% of the total visits,whereas heterospecific pollen constituted 22% of the total stigmatic pollen loads. On average, plant species received interspecific moves and HPT from 6.9 and 9.7 other species, respectively. Although the two networks were largely concordant, 21.6% of interspecific move links were not correspondingly linked by HPT, and 44.1% of heterospecific pollen transfer links were not linked by moves. Plant species with more outgoing pollinator moves tended to disperse more of their own pollen to others, as expected. Surprisingly, our data reveal that plant species which received more pollinator moves from other species tended to receive less HP, implying that only species with low acceptance of HP were likely to permit frequent pollinator moves. These new findings unveil a paradoxical relation between pollinator interspecific moves and HP receipt, suggesting an adaptive strategy of co-flowering species that reduces deleterious effects of HPT.


Assuntos
Ecossistema , Fenômenos Fisiológicos Vegetais , Polinização , Animais , China , Ecologia , Flores , Pólen , Reprodução
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