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1.
Micromachines (Basel) ; 13(2)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35208413

RESUMO

This paper presents the development of a wide-beam width, dual-band, omnidirectional antenna for the mm-wave band used in 5G communication systems for indoor coverage. The 5G indoor environment includes features of wide space and short range. Additionally, it needs to function well under a variety of circumstances in order to carry out its diverse set of network applications. The waveguide antenna has been designed to be small enough to meet the requirements of mm-wave band and utilizes a corrugated horn to produce a wide beam width. Additionally, it is small enough to integrate with 5G communication products and is easy to manufacture. This design is simple enough to have multi-feature antenna performance and is more useful for the femtocell repeater. The corrugated circularly polarized horn antenna has been designed for two frequency bands; namely, 26.5-30 GHz for the low band and 36-40 GHz for high band. The results of this study show that return-loss is better than 18 dB for both low and high band. The peak gain is 6.1 dBi for the low band and 8.7 dBi for the high band. The beam width is 105 degrees and 77 degrees for the low band and the high band, respectively. The axial ratio is less than 5.2 dB for both low and high band. Generally, traditional circularly polarized antennas cannot meet the requirements for broadband. The designs for the antennas proposed here can meet the requirements of FR2 bandwidths. This feature limits axial ratio performance. The measurement error in the current experiment comes from the high precision control on the size of the ridge.

2.
Molecules ; 25(23)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266043

RESUMO

The purpose of the study was to elucidate the anti-hepatoma effects and mechanisms of Pogostemon cablin essential oils (PPa extract) in vitro and in vivo. PPa extract exhibited an inhibitory effect on hepatocellular carcinoma (HCC) cells and was less cytotoxic to normal cells, especially normal liver cells, than it was to HCC cells, exerting a good selective index. Additionally, PPa extract inhibited HCC cell growth by blocking the cell cycle at the G0/G1 phase via p53 dependent or independent pathway to down regulated cell cycle regulators. Moreover, PPa extract induced the FAS-FASL-caspase-8 system to activate the extrinsic apoptosis pathway, and it increased the bax/bcl-2 ratio and reduced ΔΨm to activate the intrinsic apoptosis pathway that might be due to lots of reactive oxygen species (ROS) production which was induced by PPa extract. In addition, PPa extract presented to the potential to act synergistically with sorafenib to effectively inhibit HCC cell proliferation through the Akt/mTOR pathway and reduce regrowth of HCC cells. In an animal model, PPa extract suppressed HCC tumor growth and prolonged lifespan by reducing the VEGF/VEGFR axis and inducing tumor cell apoptosis in vivo. Ultimately, PPa extract demonstrated nearly no or low system-wide, physiological, or pathological toxicity in vivo. In conclusion, PPa extract effectively inhibited HCC cell growth through inducing cell cycle arrest and activating apoptosis in vitro and in vivo. Furthermore, PPa extract exhibits less toxicity toward normal cells and organs than it does toward HCC cells, which might lead to fewer side effects in clinical applications. PPa extract may be developed into a clinical drug to suppress tumor growth or functional food to prevent HCC initiation or chemoprotection of HCC recurrence.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Dano ao DNA , Extratos Vegetais/farmacologia , Pogostemon/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/química , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Feminino , Humanos , Técnicas In Vitro , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Mol Biol Rep ; 47(11): 8935-8947, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33150524

RESUMO

This study investigated the anti-leukemic effects of Cedrus atlantica extract (CAt extract) on cell cycle distribution and apoptosis in human acute myeloid leukemia (AML) cells. AML often occurs in older adults, accounting for 60% of the cases, and is likely to be resistant to chemotherapy due to multidrug resistance, resulting in early death during cancer treatment. With the increasing focus on prevention medicine, natural plant components are being used as a major source for the development of therapeutic drugs or functional foods to cure or alleviate the disease. Cedrus species are known to have anti-inflammatory, antimicrobial, antiviral, and anticancer effects; however, the anticancer effects of CAt extract have not been elucidated. In this study, CAt extract demonstrated an inhibitory effect on human leukemia cells in a concentration-dependent manner; CAt extract induced G0/G1 phase arrest via restrained protein levels of p-Rb and cell cycle-related proteins. After CAt extract exposure, the extrinsic and intrinsic apoptotic pathways were activated through caspase-8, -9, and -3 cleavage. Additionally, CAt extract suppressed VEGF, MMP-2, and MMP-9 expression. This study demonstrated that CAt extract treatment significantly reduced cell growth, cell cycle arrest in the G0/G1 phase, and induction of apoptosis, leading to leukemia cell death.


Assuntos
Apoptose/efeitos dos fármacos , Cedrus/química , Ciclo Celular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Doença Aguda , Animais , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HL-60 , Humanos , Células Jurkat , Células K562 , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Células RAW 264.7 , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Biomed Pharmacother ; 129: 110328, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535384

RESUMO

The aim of the present study was to investigate the analgesic effects and mechanism of action of Trametes versicolor (Tv) mycelium powder. Wistar rats were randomly divided into the following three or four groups: i) Saline group, fed saline; ii) Tv 500 group, fed 500 mg/kg Tv; iii) ASA 50 group, fed 50 mg/kg acetylsalicylic acid (ASA); and iv) ASA 100 group, fed 100 mg/kg ASA. Chemical formalin tests and thermal hot plate tests were used to investigate the analgesic effects of each group. ELISAs were performed to detect cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) plasma levels, and high-performance liquid chromatography (HPLC) was used for quality control the active component, oleanolic acid (OA) in Tv that had the analgesic effect. The OA content in aqueous Tv extract was found to be 11.92 % by HPLC assays. The licking frequencies in the early phase and late phase of the formalin test were significantly lower in the Tv 500 and ASA 100 groups than the saline group. The licking time in the late phase were also significantly lower in the Tv 500 and ASA 100 groups than the saline group. The plasma levels of COX-2 and PGE2 were decreased significantly in the Tv 500 and ASA 100 groups compared with that of the saline group at 60 min in the formalin test. In addition, oral feeding with 500 mg/kg Tv may effectively reduce physical pain triggered by hot plates in Wistar rats. Taken together, the acetylsalicylic acid-like analgesic effects of Tv in Wistar rats may be associated with the reduction of the plasma COX-2 and PGE2 levels.


Assuntos
Analgésicos/farmacologia , Aspirina/farmacologia , Ácido Oleanólico/farmacologia , Limiar da Dor/efeitos dos fármacos , Dor/prevenção & controle , Polyporaceae , Analgésicos/isolamento & purificação , Animais , Ciclo-Oxigenase 2/sangue , Dinoprostona/sangue , Modelos Animais de Doenças , Regulação para Baixo , Masculino , Ácido Oleanólico/isolamento & purificação , Dor/sangue , Dor/etiologia , Dor/fisiopatologia , Polyporaceae/química , Ratos Wistar
5.
Mol Med Rep ; 17(2): 3260-3266, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29257321

RESUMO

Insulin resistance is a major factor in type II diabetes development, occurring when insulin levels are normal, but do not have normal interactions with adipose, muscle or liver tissue. The present study aimed to explore the hypoglycemic effect of Antrodia cinnamomea (AC) mycelium powder by evaluating its impact on insulin resistance and plasma free fatty acid (FFA) levels in steroid­induced insulin­resistant (SIIR) rats. Male Wistar rats were administered dexamethasone for 5 days to induce insulin resistance. The SIIR rats were subsequently randomly assigned into three experimental groups (EGs) and a control group (CG), where saline was orally administered. The EGs were orally administered different doses of AC (100, 200 or 500 mg/kg) and an optimal dose for further study was determined. Changes in plasma insulin and glucose levels were calculated to investigate the hypoglycemic effect of AC. To evaluate insulin resistance, the homeostasis model assessment­estimated insulin resistance of the SIIR rats was determined. Changes in plasma FFA levels were detected and levels of insulin signal proteins (IRS­1, GLUT­4 and PI3K) were analyzed by western blot to elucidate AC's mechanism of action. The SIIR rats exhibited significantly decreased plasma glucose levels in the first 30 min, with plasma FFA levels displaying a marked downward trend (P<0.05) when they were administered the optimal dose of AC (200 mg/kg). The decrease in plasma glucose and FFA levels was significantly larger in the EG compared to the CG, and insulin signal protein levels were also significantly increased (P<0.05). The hypoglycemic effect observed may be due to decreased plasma FFA levels and increased expression of intracellular insulin signal proteins. Furthermore, insulin sensitivity was enhanced, indicating that AC acts as an insulin sensitizer in insulin resistant animal models.


Assuntos
Antrodia , Produtos Biológicos/uso terapêutico , Glicemia/análise , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Insulina/sangue , Animais , Antrodia/química , Produtos Biológicos/química , Dexametasona , Hipoglicemiantes/química , Masculino , Ratos Wistar
6.
Artigo em Inglês | MEDLINE | ID: mdl-24319475

RESUMO

Glioblastoma multiforme (GBM) is a highly vascularized and invasive neoplasm. The methanol extract of Angelica sinensis (AS-M) is commonly used in traditional Chinese medicine to treat several diseases, such as gastric mucosal damage, hepatic injury, menopausal symptoms, and chronic glomerulonephritis. AS-M also displays potency in suppressing the growth of malignant brain tumor cells. The growth suppression of malignant brain tumor cells by AS-M results from cell cycle arrest and apoptosis. AS-M upregulates expression of cyclin kinase inhibitors, including p16, to decrease the phosphorylation of Rb proteins, resulting in arrest at the G0-G1 phase. The expression of the p53 protein is increased by AS-M and correlates with activation of apoptosis-associated proteins. Therefore, the apoptosis of cancer cells induced by AS-M may be triggered through the p53 pathway. In in vivo studies, AS-M not only suppresses the growth of human malignant brain tumors but also significantly prolongs patient survival. In addition, AS-M has potent anticancer effects involving cell cycle arrest, apoptosis, and antiangiogenesis. The in vitro and in vivo anticancer effects of AS-M indicate that this extract warrants further investigation and potential development as a new antibrain tumor agent, providing new hope for the chemotherapy of malignant brain cancer.

7.
Artigo em Inglês | MEDLINE | ID: mdl-23983807

RESUMO

Aims. To evaluate the efficacy of rosiglitazone (TZD) and electroacupuncture (EA) combined therapy as a treatment for type 2 diabetes mellitus (T2DM) patients by randomized single-blind placebo controlled clinical trial. Methods. A total of 31 newly diagnostic T2DM patients, who fulfilled the study's eligibility criteria, were recruited. The individuals were randomly assigned into two groups, the control group (TZD, N = 15) and the experimental group (TZD + EA, N = 16). Changes in their plasma free fatty acid (FFA), glucose, and insulin levels, together with their homeostasis model assessment (HOMA) indices, were statistically compared before and after treatment. Hypoglycemic activity (%) was also compared between these two groups. Results. There was no significant difference in hypoglycemic activity between the TZD and TZD + EA group. The effectiveness of the combined therapy seems to derive from an improvement in insulin resistance and a significant lowering of the secreted insulin rather than the effect of TZD alone on T2DM. The combined treatment had no significant adverse effects. A lower plasma FFA concentration is likely to be the mechanism that causes this effect. Conclusion. This combined therapy seems to suppress endogenous insulin secretion by improving insulin resistance via a mechanism involving a reduction in plasma FFA. This trial is registered with ClinicalTrials.gov NCT01577095.

8.
Lasers Med Sci ; 27(3): 593-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21953118

RESUMO

The aims of this study were to establish a rat model of carotid artery injury and to evaluate its suitability for evaluating therapeutic agents active against endothelial proliferation. Wistar-Kyoto rats were injected intravenously with the photochemically reactive dyes rose bengal or Evans blue, and the carotid artery was then focally irradiated with laser light of the appropriate wavelength. Histological sections of the carotid artery were analyzed to determine the appropriate parameters for this model. Ferulic acid was used to assess the suitability of this model for drug screening. No animal died as a result of the photochemical treatment. Endothelial proliferation in the carotid artery was observed in rats injected with rose Bengal and exposed to green laser light. Ferulic acid (400 mg/kg per day) significantly (p<0.05) reduced endothelial proliferation in the carotid artery 28 days after injury in dye-treated animals compared with vehicle-treated animals. This simple experimental rat model is suitable for studying factors inhibiting endothelial thickening after vessel damage and for developing therapeutic strategies active against endothelial proliferation.


Assuntos
Lesões das Artérias Carótidas/tratamento farmacológico , Lesões das Artérias Carótidas/etiologia , Lasers de Estado Sólido/efeitos adversos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Lesões das Artérias Carótidas/patologia , Proliferação de Células/efeitos dos fármacos , Ácidos Cumáricos/farmacologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Azul Evans/administração & dosagem , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Neointima/tratamento farmacológico , Neointima/etiologia , Neointima/patologia , Fármacos Fotossensibilizantes/administração & dosagem , Ratos , Ratos Endogâmicos WKY , Rosa Bengala/administração & dosagem
9.
Life Sci ; 79(10): 967-71, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16762373

RESUMO

In this study, intravenous glucose tolerance test (ivGTT) and insulin challenge test (ICT) were applied to evaluate the influence of electroacupuncture (EA) on insulin sensitivity in rats. Firstly, hypoglycemic activity was confirmed on normal Wistar rats (36+/-12%) and streptozotocin (STZ)-induced diabetic rats (13+/-8%) after 60 min of 15 Hz EA on bilateral Zusanli acupoints. The rats were divided into the experiment group (EG) and control group (CG) randomly. After fasting, plasma glucose and insulin levels were assayed in the normal Wistar rats undergoing ivGTT. Plasma glucose levels and hypoglycemic activity were also evaluated in the normal Wistar rats and STZ diabetic rats during ICT. As the data showed, EA improved the glucose tolerance from 15 to 90 min (p<0.005 compared with the plasma glucose levels of the CG) during ivGTT. In addition, significant improvement in the Homeostasis Model Assessment (HOMA) index was found in the EG from 15 to 90 min (p<0.005 compared with the CG). More hypoglycemic activity was achieved in normal Wistar and STZ diabetic rats in the EG than in the CG (from 30 to 60 min) during ICT. In conclusion, the results suggest that 15 Hz EA at bilateral Zusanli acupoints improved glucose tolerance. Thus, EA should be considered as an alternative method for improving insulin sensitivity and/or increase insulin-hypoglycemic activity in rats.


Assuntos
Pontos de Acupuntura , Glicemia/análise , Diabetes Mellitus Experimental/terapia , Eletroacupuntura/métodos , Insulina/sangue , Animais , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Relação Dose-Resposta a Droga , Teste de Tolerância a Glucose , Masculino , Ratos , Ratos Wistar , Sensibilidade e Especificidade , Estreptozocina
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