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1.
Front Plant Sci ; 13: 957735, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36420041

RESUMO

Nitric oxide (NO) has received much attention since it can boost plant defense mechanisms, and plenty of studies have shown that exogenous NO improves salinity tolerance in plants. However, because of the wide range of experimental settings, it is difficult to assess the administration of optimal dosages, frequency, timing, and method of application and the overall favorable effects of NO on growth and yield improvements. Therefore, we conducted a meta-analysis to reveal the exact physiological and biochemical mechanisms and to understand the influence of plant-related or method-related factors on NO-mediated salt tolerance. Exogenous application of NO significantly influenced biomass accumulation, growth, and yield irrespective of salinity stress. According to this analysis, seed priming and foliar pre-treatment were the most effective methods of NO application to plants. Moreover, one-time and regular intervals of NO treatment were more beneficial for plant growth. The optimum concentration of NO ranges from 0.1 to 0.2 mM, and it alleviates salinity stress up to 150 mM NaCl. Furthermore, the beneficial effect of NO treatment was more pronounced as salinity stress was prolonged (>21 days). This meta-analysis showed that NO supplementation was significantly applicable at germination and seedling stages. Interestingly, exogenous NO treatment boosted plant growth most efficiently in dicots. This meta-analysis showed that exogenous NO alleviates salt-induced oxidative damage and improves plant growth and yield potential by regulating osmotic balance, mineral homeostasis, photosynthetic machinery, the metabolism of reactive oxygen species, and the antioxidant defense mechanism. Our analysis pointed out several research gaps, such as lipid metabolism regulation, reproductive stage performance, C4 plant responses, field-level yield impact, and economic profitability of farmers in response to exogenous NO, which need to be evaluated in the subsequent investigation.

4.
Am J Sports Med ; 42(9): 2193-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25035175

RESUMO

BACKGROUND: Meniscectomy is frequently performed in elite soccer athletes to allow return to a high level of performance as early as possible. Although lateral meniscectomy is known to have more serious long-term sequelae than medial meniscectomy, little is known about the effect of lateral meniscectomy on the time to return to play during the early recovery phase in professional soccer players. HYPOTHESIS: Lateral meniscectomy results in longer times to return to preinjury level of competition and a higher incidence of adverse outcomes compared with medial meniscectomy in elite professional soccer players. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A single-surgeon database containing the injury history and operative details of elite soccer athletes from 2005 to 2009 was used to identify players who had undergone an isolated partial lateral or medial meniscectomy. The time to return to preinjury level of competition, the incidence of adverse events during early recovery, and the need for further arthroscopy were recorded. Time to return to play was analyzed by using the Kaplan-Meier method. A multivariate analysis was used to control for age, location of meniscectomy, percentage of meniscus excised, and type of tear. RESULTS: Ninety soccer players were identified, of which 42 had a lateral meniscectomy and 48 had a medial meniscectomy. The median time to return to play, to the nearest week, was longer in the lateral group than the medial group (7 vs 5; P < .001). At all time points after surgery, the cumulative probability of returning to play was 5.99 times greater (95% confidence interval, 3.34-10.74; P < .001) after medial meniscectomy. More lateral meniscectomy cases experienced adverse events related to pain/swelling-29 (69%) vs 4 (8%) (P < .001)-and required a second arthroscopy: 3 (7%) vs 0 (P = .098). CONCLUSION: The time to return to preinjury level of competition is significantly longer after lateral than medial meniscectomy in elite professional soccer athletes. Lateral meniscectomy has a higher incidence of adverse events in the early recovery period, including pain/swelling and the need for further arthroscopy. It is also associated with a significantly lower rate of return to play. These findings form the basis of an important discussion that must be had with player and club before a lateral meniscectomy is performed in elite soccer athletes.


Assuntos
Artroscopia/métodos , Recuperação de Função Fisiológica , Futebol/lesões , Lesões do Menisco Tibial , Desempenho Atlético , Humanos , Imageamento por Ressonância Magnética , Masculino , Meniscos Tibiais/cirurgia , Fotografação , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
5.
Anticancer Res ; 30(9): 3629-35, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20944146

RESUMO

We observed previously that quercetin can increase the activity of the differentiation markers alkaline phosphatase and dipeptidyl peptidase in Caco-2 colon cancer cells. In the present work, we compared the effects of quercetin on cell proliferation and differentiation with the action of related flavonols and quercetin glycosides. Relative to the action of quercetin, effects on growth and enzyme activities did not always follow parallel trends but quercetin 3-glucoside was notably more potent in both respects while quercetin rutinoside was less active. Of the compounds examined, baicalein and myricetin caused the greatest production of hydrogen peroxide when incubated with the medium. Flavonols can have pro-oxidant effects, but our data suggested that this action was not the sole determinant of growth inhibitory or differentiating effects on Caco-2 cells. Our data indicated that effects of quercetin on colon cancer cell lines can be greatly affected by glycoside modification.


Assuntos
Fosfatase Alcalina/biossíntese , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/enzimologia , Flavonóis/farmacologia , Glicosídeos/farmacologia , Células CACO-2 , Diferenciação Celular/efeitos dos fármacos , Células HT29 , Humanos , Quercetina/química , Quercetina/farmacologia
6.
Gastrointest Endosc ; 70(3): 407-13, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19699975

RESUMO

BACKGROUND: There is no simple method to measure intravariceal pressure in patients with esophageal varices. OBJECTIVE: Our purpose was to develop a new noninvasive technique to measure resting intravariceal pressure and wall tension. DESIGN: A model was developed. A long balloon (varix) was fitted inside an airtight cylinder (esophagus). Fluid ran through the model varices to maintain 5 different constant pressures. An endoscope was placed in the model esophagus, and pressure was increased by air insufflation. The endoscopy and pressure readings from the esophagus and varix were recorded continuously until variceal collapse. SETTING: Patient studies were done in an endoscopy suite with the patient under fentanyl and midazolam sedation. PATIENTS: Esophageal pressure was measured during air insufflation in patients with varices until the varices collapsed. EUS was used to measure radius and wall thickness to calculate wall tension. RESULTS: In the varix model, the mean (SD) intraluminal esophageal pressures at variceal flattening for the model varices at 5, 10, 15, 20, and 25 mm Hg were 5.69 (0.34), 11 (0.32), 15.72 (0.51), 21.55 (0.63), and 25.8 (0.14) mm Hg. The correlation between actual and measured variceal pressure in the model at variceal flattening was r = 0.98. In the patients, a total of 10 varices in 3 patients were evaluated. The mean (SD) for the varices in each subject was 12.16 (2.4), 23.2 (1.3), and 6.5 (2.2) mm Hg for subjects 1, 2, and 3, respectively. CONCLUSION: Standard endoscopy with air insufflation and manometry can be used as an accurate, simple, and reproducible method to measure intravariceal pressure.


Assuntos
Varizes Esofágicas e Gástricas/diagnóstico , Esofagoscopia/métodos , Manometria/métodos , Processamento de Sinais Assistido por Computador , Endossonografia/métodos , Varizes Esofágicas e Gástricas/complicações , Esôfago/irrigação sanguínea , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Insuflação , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Músculo Liso Vascular/fisiologia , Pressão , Medição de Risco , Sensibilidade e Especificidade , Resistência à Tração , Gravação em Vídeo
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